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sidegrinder
10-19-2007, 01:00 AM
I would like to buy a set of micrometers up to 3 or 4". The 1" I currently have is an old-school vernier with a friction thimble. How are the digital (not electronic) ones, are they very repeatable? Also, how much better are the ratcheting thimbles? Anybody had good luck with "quality imports"? Tell me what works for you guys...

oldtiffie
10-19-2007, 07:27 AM
Hi sidegrinder

Good post.

I saw some very good micrometers (0 - 3") at Littlemachineshop.com (USA) for US$29.25 - and they are calibrated/indexed to "tenths".
http://www.littlemachineshop.com/products/product_view.php?ProductID=1248&category=

And right next to them is the "Starret" equivalent at US$440.00
http://www.littlemachineshop.com/products/product_view.php?
ProductID=1836&category=

Now if anyone cares to explain to me why Starret is worth nearly 15 times as much I am willing to listen - but I will tell you that a "...because its Starret and its made in the USA etc. etc. .............." excuse just will not "wash".

Little machineshop has its reputation to maintain and so I don't think they would be interested in selling "rubbish".

I've bought a lot of stuff from them and CDCO.com lately (both in the USA) and all of it has been very good to excellent.

I have been using micrometers etc. for a long time. I have tried the digital ones. I do have an open mind. The digital "mic's" are a bit awkward to hold but they do the job.

Don't be put off by all the "noise" about "battery-failures" etc. as regards any digital equipment. Batteries are dirt cheap - so keep a store of them and replace as necessary.

7018
10-19-2007, 09:11 AM
I have Starrett, B&S, And some Slocomb I also have a import set that goes up to 6 inch. I;ve check them with all the others and they read the same.I think the set was about 40 bucks.I also have some import 1 inch digital that work fine..

Swarf&Sparks
10-19-2007, 09:45 AM
FWIW, I bought the concentric indicator and digi calipers from LMS and am well satisfied with both as well as prompt service to Oz.
Usual disclaimer, just a satisfied customer.

ahidley
10-19-2007, 10:40 AM
I ordered a set of import 0-6 w/standards from www.shars.com yesterday..$69 # 303-2653N Their website is not complete, but they have an awsome free catalog

piniongear
10-19-2007, 10:51 AM
I have two digital calipers and they are Starrett brand. Both of these have failed over the time I have had them. The 'internals' failed and Starrett repaired both of them, but at a cost of $107 for each repair. Starrett did not actually repair them, but rather replaced the head on each. I guess this is more cost effective.
I have no use for battery powered instruments after this experience. Just give me a set of Starrett 436 Series mics and I am happy........pg

lenord
10-19-2007, 11:07 AM
I got a set of 1-6" manual mics from Shars a few months ago. The quality and accuracy are stunning for the price. I really don't see how they can be made so cost effectively, even with low wage employees.

Lenord

Fasttrack
10-19-2007, 11:12 AM
I've got a set of craftsman brand from 0-4" vernier. They are actually made by SPI but craftsman gets to stamp their name on them. I got the set for 100 bucks and all of the larger sizes besides 0-1" have ratchet and friction thimbles. The 0-1" has a friction thimble only. I personally like the ratchet mechanism becauses i work out in a garage that is likely to leave my fingers pretty cold. In the winter time i have a hard time "feeling" how much squeeze or torque i'm putting on the mircrometer. With the ratchet one, it doesnt matter how much you squeeze the thimble, it starts ratcheting at the same point every time. I find the ratchet style much more repeatable than friction - seems like friction you have to calibrate them to your own personal feel.

I haven't used them much but they seem pretty decent - they came with standards and they have nice insulators on the frame and the standards to prevent body heat from throwing stuff out of whack. Some of the nicer micrometers come with tiny little insulators that are hard to keep a hole of, but these have the insulation pad over the entire side of the frame so its easy to hold.

Not sure about the mechanical digital ones - i always think they look goofy and not very accurate, but i'm sure thats not true. Thats just a purely asthetic statement! :)

SGW
10-19-2007, 12:22 PM
I mostly use a Starrett 0-1" micrometer that I bought used, quite a few years ago. It's still a good micrometer.

At one point when I was working in high tech and actually had money, I bought a new Starrett 1-2".

Over the years I've picked up used Starrett 2-3" and 3-4". Since I use them infrequently, I decided "good used" was good enough, and it has been.

All except the 3-4" have the 0.0001" vernier and carbide faces.

I've got both friction thimble and ratchet, and of the two I think I favor the ratchet type slightly. Mostly I don't bother with either one and go buy "feel."

Being somewhat of a Luddite, I've avoided any of those newfangled electronic gizmos.

A machine shop friend of mine, a professional machinist, likes Lufkin micrometers. They're no longer made, of course, but "good used" are available. Others are partial to Brown & Sharpe.

Fasttrack
10-19-2007, 02:17 PM
Being somewhat of a Luddite, I've avoided any of those newfangled electronic gizmos.

You know, that pretty much sums it up for me too. I really dont like electronic stuff if i can avoid it - which is weird since i kinda grew up with it.

I guess i should point out that those craftsman ones had carbide faces and etc.

Maybe its because i'm a rookie, but i found that the friction ones are dependent upon "feel" just to a lesser degree than if you just turn in it normally. I've noticed differences when measuring standards of +/-.00015 (the last digit being estimated, obviously) with friction because i can squeeze the thimble a little bit and get a smaller reading. For that reason, i like the ratchet ones. I dunno - maybe i'm doing something wrong... on the other hand .0001 isn't too bad :D

BadDog
10-19-2007, 02:46 PM
I've accumulated a selection, I use various for different things.

I've got analog (not electro) digitals from Mitu in replaceable anvil and standard 0-1 configs. Very nice and easy to read. Digi to 0.001, and regular marks with vernier to 0.0001 if you want/need it. I tend to grab these somewhat frequently just because it doesn't take any thought to use, and they are pretty much dead on with less chance of a miss-read. Also MUCH easier and definitely the "go to" mic if the reading must be taken "in place" for some reason, and lighting/angle is bad.

But, I have a slant line B&S mics ranging from 0-3" that I can't seem to leave alone. Even the 0-1 that I could use the Mitu standard anvil for, I am actually more likely to grab the B&S than the Mitu (unless the Mitu is already out). I can't really explain it, but for some reason I like (and trust?) the B&S more.

I've also got Starrett and Lufkin, pretty much never use them as I prefer either the B&S or Mitu, apparently depending on my mood...

oldtiffie
10-19-2007, 06:16 PM
You know, that pretty much sums it up for me too. I really dont like electronic stuff if i can avoid it - which is weird since i kinda grew up with it.

I guess i should point out that those craftsman ones had carbide faces and etc.

Maybe its because i'm a rookie, but i found that the friction ones are dependent upon "feel" just to a lesser degree than if you just turn in it normally. I've noticed differences when measuring standards of +/-.00015 (the last digit being estimated, obviously) with friction because i can squeeze the thimble a little bit and get a smaller reading. For that reason, i like the ratchet ones. I dunno - maybe i'm doing something wrong... on the other hand .0001 isn't too bad :D

Thanks fasttrack.

Last paragraph was a very good comment.

If you are getting that sort of accuracy you are doing OK. Perhaps a re-check every so often with a "known" size will get and then keep that skill up.

I know of some (so-called) "machinists" that use a micrometer as a "G" clamp and they can "spring" a caliper to almost anything.

So you are doing better than a lot of those who have been at it for a long time. You WILL get better - because you want to - whereas "they" WON'T because they cannot or will not.

You are doing very well.

7018
10-19-2007, 06:48 PM
If you look on E-Bay under vintage micrometers, You can get some pretty good deals..

Marc M
10-19-2007, 07:00 PM
I'm curious how many folks who have purchased micrometers of Chinese origin have actually checked their accuracy across their range. I too purchased a 1"-6" .0001" set from Shars. I was a little disappointed when I checked them with gage blocks. I'm sorry, I don't recall the specifics as this was about 8 months ago, but I did find that all had error across their range. They were accurate at full opening, but not at intervals of their range. I think I was checking them at .2" intervals. IIRC, the variance was in the +/- .0003 range. I checked each several times and came up with pretty consistant numbers each time turning the thimble directly. I found the ratchets to be a little rough and I wasn't getting a consistant reading (using 3 clicks). Keep in mind this was just a quick check when I got them and it's possible they'll settle in with use. In comparison, the B&S 1" & 2" .001" mics I have were within a tenth as close as I could tell as they lacked a vernier scale, but they're also 60+ years old. I didn't investigate it any further, just noted that I'd need to use blocks with them if tenths was going to matter in the measurement.

It would be interesting to see what other members have found regarding the accuracy. It's entirely possible I may have the exception rather than the rule as we are all probably too familiar with inconsistent Chinese QC.

tattoomike68
10-19-2007, 07:39 PM
Some of our bigger micrometers (5"+)are NSK (JAPAN) , they work just fine.

Myself I like my mitutoyo mics, they have served me well for years.

I dont care for digtal readouts or other things on a mic. I can read it just fine.

lane
10-19-2007, 08:32 PM
I have 0-7 inch at work Brown &Sharp. At home a mixed lot . Starrett, B&S, Lufkin I like Lufkin . Some have friction thimbles which I prefer some have the ratchet thimble and some have nothing but you own feel. The Starrett B&S Lufkin and Mitutoyo will last a life time and then more . these Chinese Tools are another question.

oldtiffie
10-19-2007, 11:57 PM
I'm curious how many folks who have purchased micrometers of Chinese origin have actually checked their accuracy across their range. I too purchased a 1"-6" .0001" set from Shars. I was a little disappointed when I checked them with gage blocks. I'm sorry, I don't recall the specifics as this was about 8 months ago, but I did find that all had error across their range. They were accurate at full opening, but not at intervals of their range. I think I was checking them at .2" intervals. IIRC, the variance was in the +/- .0003 range. I checked each several times and came up with pretty consistant numbers each time turning the thimble directly. I found the ratchets to be a little rough and I wasn't getting a consistant reading (using 3 clicks). Keep in mind this was just a quick check when I got them and it's possible they'll settle in with use. In comparison, the B&S 1" & 2" .001" mics I have were within a tenth as close as I could tell as they lacked a vernier scale, but they're also 60+ years old. I didn't investigate it any further, just noted that I'd need to use blocks with them if tenths was going to matter in the measurement.

It would be interesting to see what other members have found regarding the accuracy. It's entirely possible I may have the exception rather than the rule as we are all probably too familiar with inconsistent Chinese QC.

Thanks Marc.

You raised a very important and all too often over-looked or ignored point as regards variability of accuracy throughout a tool's operating range.

Micrometers for instance are normally only provided with "check blocks/gages" for use at the extreme ends of their operating range whereas just about all use and wear is encountered between these ends and any errors need to be identified and compensated for as required.

The problem you identify is not unique to you or any tool really.

Quite often this "problem" can be allowed for by checking your micrometer or what-ever against several "known" sizes throughout the - say micrometer's - operating range and tabulating those results as errors and corrections to be made or allowed for in future use when real accuracy is needed.

Many tools such as "Slip/gage-blocks" come with such a table for just that purpose.

And despite the advice ("sour grapes"??) from some others, I think that you will find that given that "China" production processes are so automated that they will be very often be as good as it gets.

But, as always, there are "classes" of finish and excellence as regards use and accuracy - and this should be allowed for.

wierdscience
10-20-2007, 12:43 AM
TMX is a good brand if you want better than China(Poland),but can't swing the Starrett or Mito price.I have a set of 1-3 and love them.

http://www.toolmex.com/Tools/TMeasuring.asp

I also have a couple sizes of Starrett digital(mechanical) mics.I like them since the dgital displays cut down on mistakes when I work really late on occasion.

cybor462
10-20-2007, 12:22 PM
Just to add my 3 cents :p I have a set of 0-3 as listed in the toolmex catalog. I have a number of different sets different brands but this one is an exact match. I did not get them there. I got them at HF yes before you rip this apart they are that exact set does not say china nor does it say any country actually.

It is that set. Now for the lowdown.... they are carbide tipped but the tip on the 1-2 has a very very very small chip on the outside edge, the flat measuring surface edge. It is not raised up so it does not effect anything except to those that would say "those are junk they are chipped"

They are very accurate and the ratchet is as good as a Starret. I have an old Starret 0-1 from my aircraft shop days.

So the lesson learned, even though it may be sold as one brand it may just be another. The pesky people that hate Chinese may have missed the boat. You may think you got Chinese but you may have Poland. Not sure if it is that much different. I can say Bison seems to be a quality tool so at least there I can say Poland is ok.

Now I have spoken... :rolleyes:

J Tiers
10-20-2007, 11:31 PM
I have a mixed collection. The 0-1 is a Mitutoyo, and very nice. The 2" and 3" are Lufkin, and also nice. The 4" is a VIS (Polish) and quite acceptable. All with carbide faces. Any of them are good.

I also have a POS Tumico 0-5" set with interchangeable anvils. That is a horrible thing, just a bit worser than the "General" brand cast zinc cheapos. Terrible "feel". That tubular frame thing was NOT a good idea, they are the "softest" feeling things ever.

I also have a funky little 0-1/2" Starret, it 'works", nothing to write home about, and a 1" Starrett (#203) ditto.

The metric stuff is some furrin company, and "OK"

I guess the Mit, and the Polish stuff , along with Lufkin, seem the best to work with.

lazlo
10-20-2007, 11:45 PM
Some of our bigger micrometers (5"+)are NSK (JAPAN) , they work just fine.

Myself I like my mitutoyo mics, they have served me well for years.

I've got two Mitutoyo digital micrometers -- they're both excellent. Suprisingly, I like the older model with the crackled paint finish better than the fancy new IPS67 (coolant proof) model -- it's heavier, and more solidly built.


And despite the advice ("sour grapes"??) from some others, I think that you will find that given that "China" production processes are so automated that they will be very often be as good as it gets.

From the pictures I've seen of the Chinese factories, including Sieg's, they're mostly manual, with a large portion of the labor from teenage girls.

oldtiffie
10-21-2007, 06:50 AM
I've got two Mitutoyo digital micrometers -- they're both excellent. Suprisingly, I like the older model with the crackled paint finish better than the fancy new IPS67 (coolant proof) model -- it's heavier, and more solidly built.



From the pictures I've seen of the Chinese factories, including Sieg's, they're mostly manual, with a large portion of the labor from teenage girls.

Thanks lazlo.


From the pictures I've seen of the Chinese factories, including Sieg's, they're mostly manual, with a large portion of the labor from teenage girls.

In which case I'd suggest that those girls are highly capable - probably better than many on this forum.

If they can negate the need for automation and turn out as good and competitive a product as "Seig" then not only are they magnificently skilled but they can give many others - especially men - a lot of justification to be very very worried.

There are at least 2 on this forum who have a lot of knowledge of and use and admiration for "Seig". Same on the "CNC" forum.

I subscribe to "American Machinist" as well. From reading some of the lead articles there it seems that US firms that (are to or do) "succeed" are very highly automated and shove their machinists pretty hard and keep their numbers down to the absolute minimum. Not a pretty sight or out-look in a lot of cases it seems.

With all that skilled hand/manual work and the work-load and forward orders they have - have you considered working for Seig (in China)? Think of the bonuses - (and) all them women!!!

lazlo
10-21-2007, 08:37 AM
There are at least 2 on this forum who have a lot of knowledge of and use and admiration for "Seig". Same on the "CNC" forum.

John Stevenson does business with Sieg, but I doubt very much that he is impressed with the Sieg factory.

Here are pictures of the inside of the Sieg factory, when Chris Wood (owner of Little Machine Shop) visited there. From the various PBS and independent film documentaries, and pictures that news magazines have published, this is very typical of a Chinese factory: antiquated machines and almost no automation, no safety controls (notice not a pair of safety glasses in sight), and no quality control.

Great place to buy a hobby lathe or mill, but do you want to buy a precision measuring device here? There's a good reason Little Machine Shop can sell 3 micrometers for $40...

http://www.littlemachineshop.com/gallery/images/2004-06%20SIEG%20Factory%20Tour%20China/PICT0336.JPG

Chris Wood's caption:
"A variety of machines in the SIEG plant including shapers, horizontal mills and lathes. Many of these machines have not been used in the US in 40 years."
http://www.littlemachineshop.com/gallery/images/2004-06%20SIEG%20Factory%20Tour%20China/PICT0309.JPG

http://www.littlemachineshop.com/gallery/images/2004-06%20SIEG%20Factory%20Tour%20China/PICT0320.JPG

http://www.littlemachineshop.com/gallery/images/qdig-files/converted-images/2004-06%20SIEG%20Factory%20Tour%20China/med_PICT0325.JPG

oldtiffie
10-21-2007, 09:07 AM
John Stevenson does business with Sieg, but I doubt very much that he is impressed with the Sieg factory.

Here are pictures of the inside of the Sieg factory, when Chris Wood (owner of Little Machine Shop) visited there. From the various PBS and independent film documentaries, and pictures that news magazines have published, this is very typical of a Chinese factory: antiquated machines and almost no automation, no safety controls (notice not a pair of safety glasses in sight), and no quality control.

Great place to buy a hobby lathe or mill, but do you want to buy a precision measuring device here? There's a good reason Little Machine Shop can sell 3 micrometers for $40...
....................................
..................................

Chris Wood's caption:
"A variety of machines in the SIEG plant including shapers, horizontal mills and lathes. Many of these machines have not been used in the US in 40 years
.......................................
........................................


Hmm. Maybe so.

But did Chris Wood buy anything there?

Given that Chris Wood buys so much really excellent "stuff" from China and taking your advice that so many factories are so bad in so many ways, its seems reasonable to assume that there were very few of the optimal standard that you think is necessary for Chris Wood (or anyone else) to buy anything let alone such high quality stuff as comes out of China.

My logic may be twisted and so might I be but I don't think that I or my logic (or my naivety either) is that bad!!

I seem to recall that those machines that have not been used in the USA for "X" number of years seem to be in plentiful supply and doing excellent work in some of the work-shops of members of this forum. And I'd bet that some of the HSM work-shops are not a great deal different either. And despite your adverse opinions, they seem to be "getting by" quite well.

Seems to me that those "slaves" are not being pushed or harassed to hard or far. Not a "Simon Legree" or a "Galley-slave Master" (or galley slaves) in sight so far as I can see.

Re your comment/question:


Great place to buy a hobby lathe or mill, but do you want to buy a precision measuring device here?


My answer?

"Too bloody right I would if they are turning out Sieg quality".

And as for your comment re. John Stevenson:


John Stevenson does business with Sieg, but I doubt very much that he is impressed with the Sieg factory.


I note that you stay away from criticizing John for dealing with such inferred bad quality as you seem to think come from the Seig stuff that he buys.

I will be damned if I would presume seek to speak for John.

I rather hope that John can and will speak for himself in this regard.

And FWIW, and to clear up a point or two that may need addressing, I am NEITHER "pro" not "anti" anything "China". I am quite neutral and keep an open mind and just judge the quality, cost and suitability of the item/s under review for what I want them for - no more and no less. I don't dislike the people in China.

And just for balance, the same applies to the USA and its people - and a lot of other countries and their people as well.

lazlo
10-21-2007, 09:20 AM
And I'd bet that some of the HSM work-shops are not a great deal different either. And despite your adverse opinions, they seem to be "getting by" quite well.

Au contraire Tiffie. Most of us here are Home Shop Machinists. The original poster, a home-shop machinist, asked about buying a micrometer. There were a variety of suggestions, including Starrett, Mitutoyo, NSK, Lufkin, VIS, ... But you were the only one who posted that the Chinese calipers you bought from Little Machine Shop were fine, and implied that that other HSM'ers recommending Western tools had "Sour Grapes."


And as for your comment re. John Stevenson:

I note that you stay away from criticizing John for dealing with such inferred bad quality as you seem to think come from the Seig stuff that he buys.

Tiffie, you were blatently implying that the micrometers you bought from Little Machine Shop must be fine, because John Stevenson does business with Sieg. I think that's more than a little disingenuous.


There are at least 2 on this forum who have a lot of knowledge of and use and admiration for "Seig".

oldtiffie
10-21-2007, 09:50 AM
Au contraire Tiffie. Most of us here are Home Shop Machinists. The original poster, a home-shop machinist, asked about buying a micrometer. There were a variety of suggestions, including Starrett, Mitutoyo, NSK, Lufkin, VIS, ... But you were the only one who posted that the Chinese calipers you bought from Little Machine Shop were fine, and implied that that other HSM'ers recommending Western tools had "Sour Grapes."



Tiffie, you were blatently implying that the micrometers you bought from Little Machine Shop must be fine, because John Stevenson does business with Sieg. I think that's more than a little disingenuous.

Hi lazlo.



... But you were the only one who posted that the Chinese calipers you bought from Little Machine Shop were fine, and implied that that other HSM'ers recommending Western tools had "Sour Grapes."



..................... and implied that that other HSM'ers ..................

Now there is some disengenuity. I suggest that you read in "... and implied that SOME other HSMers .....................................

And:


Tiffie, you were blatently implying that the micrometers you bought from Little Machine Shop must be fine, because John Stevenson does business with Sieg. I think that's more than a little disingenuous.

how did your draw THAT conclusion from anything I wrote?

I have to admire your "creative interpretation" of what I said and my intent.

If you have a direct question - ask it - and I will reply - directly.

And for the record:
1.
I have no reason to make or infer any connection between John Stevenson and/or my opinion of any "China" stuff that I but from any source - and there are lots of which LMS is but one;

2.
Some - but by no means all or even most - but certainly some - never seem to miss "rubbishing" something irrespective of whether the poster likes it or not, price, quality or suitability for purpose for seemingly no other reason that it is (from) "China";

3.
The "China stuff" I have is excellent for its intended purpose so far as I am concerned; and

4.
I would not criticise anyone or their choice of tool or equipment solely based on the "source" without informed and subjective comment about that particular item and its intended use.

Thank you.

wierdscience
10-21-2007, 09:53 AM
I have a Sieg mill,it was a kit,but it was also less than $500 so what?The Seig stuff is like anyother product on the face of the Earth,quality is reflected by price %90 of the time.

Chinese mics I have had a few as well as some calipers mostly dial types,but I did not buy them from HF as not all China measuring tools are created equal.If you see a 1" mic for $7 it's not going to be very accurate I can almost guarranty because I know for a fact that Chinese factories"grade" product and do sell seconds at a discount.This is true of powertools and electric motors.

In a given factory the top 10% of production will got to American or European names,the next 30% will go to MSC,Travers,KBC etc.The next 30% will go to Grizzly,HF and some others with the bottom of the barrel junk going to Cummins,Homier and some other "gypsy" tool vendors,but occasionally some of it slips into Grizz and HF.

I had a 1" mic I bought from KBC,China cost $25 way back when and I still use it for a throw around mic.I checked it with a set of gauge blocks and found it good to .0001" over the entire range,good enough.I checked about six of the $8.95 Kits,HF and a few others mics and found them to be all over the place,one came in .0001",but the rest ranged all the way up to .002" out at maximum reading.

This observation is niether pro or anti-China just a re-affirmation of the old saying-"you get what you pay for".If it's too cheap,then it probably is.

cybor462
10-21-2007, 10:11 AM
Chinese mics I have had a few as well as some calipers mostly dial types,but I did not buy them from HF as not all China measuring tools are created equal.If you see a 1" mic for $7 it's not going to be very accurate I can almost guarranty because I know for a fact that Chinese factories"grade" product and do sell seconds at a discount.This is true of powertools and electric motors.

In a given factory the top 10% of production will got to American or European names,the next 30% will go to MSC,Travers,KBC etc.The next 30% will go to Grizzly,HF and some others with the bottom of the barrel junk going to Cummins,Homier and some other "gypsy" tool vendors,but occasionally some of it slips into Grizz and HF.



Not looking for a bashing but how do you know for a fact. I would be really interested where you came up with the stats on what % of what goes to which company.

J Tiers
10-21-2007, 10:20 AM
As far as the working conditions in chinese factories...... They are the reason why people do NOT want to work in them any more, trying instead to get to bigger cities and office type work. That, and the cultural factors that affect the manual labor vs "think worker" social status, which tend to be somewhat more strong all across asia and through the middle east.

I have actually been IN chinese factories. Not machine tool factories, but I see no particular reason why they should be a great deal different. At the time I was there, it was quite typical for the workers to live in a dormitory, often above the factory, sometimes adjacent to it.

You have to understand that the workers have come in from out in the country for a 'city job". That is the reason for the dormitories. However, they are indeed at work for typically longer hours than we work, and from my observation, don't always look so happy. Not surprising, since they are basically traveling far from home just in order to work and send money home. Pleasure doesn't come into the equation, and there isn't a whole lot to do after hours when the entire area for miles around is made up of similar setupos of factory and dormitory.

Simon Legree? I saw no bullwhips ............. but the work is fast paced, and the line moves right along, so you have to keep up. Not surprising if a few items get away without being completely finished, particularly at the end of a long day.

Remember, NOBODY decided to buy from china because the established industry (!) had such a high reputation for quality, or because of the highly skilled (!) workforce..

No, they bought from china because "the same thing" (!) could be gotten for a lot cheaper, because in china you paid NOTHING for labor. LABOR IS FREE. (not actually cost-less, but so cheap who cares.)

Another factor is that lots of quick-buck artists exist in china also. They are willing to set up a factory to make say, micrometers. And they will look just like a "real" one. But they may not be MADE in the way a real one is made..... the difference being the processes. And the processes is what distinguishes consistent quality from inconsistent.

When labor is FREE, you throw labor at every problem. So precision grinding is replaced by hand fitting. The result, because of less skilled workers, can be inconsistency.

The emphasis in many cases is on what is OUTSIDE AND VISIBLE. If you can't see it, it is OK to use chisels and files, or flint scrapers and stone hammers, and the heck with precision.

Here is an example.... I bought an X-Y table for the drill press. It looks fine, nice shiny handles and reasonably good finish all over.

I wanted to re-work the handle on one axis because it was a bit stiff. When I took off the handle, this is what I found on the end of the "lead screw". Obviously the outside form was important, and anything "hidden" was to get done any way that seemed to work.

While less expensive than a US-made, or Swiss X-Y table, it wasn't THAT cheap....

Think about this for a minute..... You can buy a whole Sieg mini-lathe for $399, and I have seen them cheaper. The X-Y table cost about $100 on sale. There is more than 4x the precision stuff in a lathe vs an X-Y table. The X-Y table is pretty much the same thing as the compound and crosslide. There is still the bed, the whole headstock including the spindle, tailstock, motor drive and controls, gearboxes, etc, etc.

So what corners are cut in that mini-lathe to get it to only 3 or 4 x the cost of a simple X-Y table?

In your answer, consider the fact that the makers of the X-Y table (in china) ALREADY had to cut corners severely to get to their price for a simple table.

The wonderful x-axis screw. This photo INCLUDES the BEARING area, which is the ridgy area at far left. The smoother area is where the adjustable (supposedly, it was horribly stiff) dial runs, the rest was inside the handle and of course the nut on the end.

http://img.photobucket.com/albums/0803/jstanley/chinlead.jpg

lazlo
10-21-2007, 10:20 AM
Now there is some disengenuity. I suggest that you read in "... and implied that SOME other HSMers

Actually, I had to re-read your post Tiffie, because you edited your post to tone-down the "Sour Grapes" comment in response to Marc's comment about his bad personal experience with the quality/accuracy of the Chinese micrometers.


I would not criticise anyone or their choice of tool or equipment solely based on the "source" without informed and subjective comment about that particular item and its intended use.

Tiffie, we all have Chinese (or Taiwanese) tools in our shop, so we're all very well aware of the price/performance tradeoffs, and no one is disparaging anyone else for buying, or using, Chinese tools.

But after a dozen or so recommendations from other HSM'ers for Starrett, Mitutoyo, Brown and Sharpe, NSK, Lufkin, VIS, you posted the opinion that the Chinese micrometers you got from LMS were fine, and "as good as it gets" (your words), and that the advice from the others for Western micrometers was "Sour Grapes."

cybor462
10-21-2007, 10:22 AM
I had a 1" mic I bought from KBC,China cost $25 way back when and I still use it for a throw around mic.I checked it with a set of gauge blocks and found it good to .0001" over the entire range,good enough.I checked about six of the $8.95 Kits,HF and a few others mics and found them to be all over the place,one came in .0001",but the rest ranged all the way up to .002" out at maximum reading.



I was thinking about this statement as I have seen it used when discussing cheaper brands. I was wondering how many people use cheap import gauge blocks to test their cheaper mics. And how many will trust what they find. In the same frame of mind of cheaper imports being flawed how can you trust the gauge blocks?

lazlo
10-21-2007, 10:28 AM
The Seig stuff is like anyother product on the face of the Earth,quality is reflected by price %90 of the time.
...
This observation is niether pro or anti-China just a re-affirmation of the old saying-"you get what you pay for".If it's too cheap,then it probably is.

Weird nailed it. I have a Jet 5x6 bandsaw and a Sieg mini-lathe, and I just bought a Harbor Freight vibratory tumbler yesterday. The tumbler is a poor copy of the Lymann tumbler, but it vibrates, and seems to work well enough for my needs. It was cheap enough ($40) that if it dies in a year, it will still have paid for itself.

Do the folks who pay several hundred dollars for a real Lymann tumbler have sour grapes? No way! They just have a more extensive need for a tumbler than I do ;)

lazlo
10-21-2007, 10:34 AM
I was wondering how many people use cheap import gauge blocks to test their cheaper mics. And how many will trust what they find. In the same frame of mind of cheaper imports being flawed how can you trust the gauge blocks?

Very interesting question! The Mitutoyo micrometers come with a Class A ceramic gage block for calibration, and I checked both my Mit micrometers against the gage block, and against a Class AA 8-piece Brown and Sharpe gage block set I bought, and they were dead-on.

I also bought a Chinese Grade B 81-piece gage block set (no, really :) ), but I paid extra for a NIST-traceable set. Now, the certs could be FOS, like Chinese horsepower ratings, but I compared the gage block certs against the micrometer readings, and they were balls-on (to the Class B tolerances).

I'd be curious to know how the non NIST-traceable Chinese sets stack up (sorry, couldn't help it ;) ).

wierdscience
10-21-2007, 11:17 AM
Not looking for a bashing but how do you know for a fact. I would be really interested where you came up with the stats on what % of what goes to which company.

Where I work we are an industrial supply,machineshop and toolstore,we also deal in used machinery.We buy our China tools and PT componets direct from the importers and we try to weed out the junk before we sell it most times.We sell at a higher price than does HF,but we generally have better quality.Our sales are low since most people don't know what quality is,hince the $100 HF cherry picker wieghing #105 selling better than our $212 weighing #196.HF folds unexpectantly and the other doesn't.

Most of the importers we deal with are first or second generation Chinese.One in particular imports powertools and re-labels them here,they do thier own in-house grading as not all Chinese vendors are 100% honest in thier assesments.The main grading is insulation strength,the motors are megged,if they meg out above 1,000volts they fall in the top tier,second tier is 600volts and third is 600>(parts machines)These grinders look identical.but the "brand names"(peel and stick labels) on them are different as is the selling price.The percentages will vary from what I used as an example,but it is not uncommon to see several "brands" rolling out of Chinese assembly shops.
They used to buy from venders that did in house grading,but there was a tendancy to fudge the numbers and that costs money in returns by customers,bad PR etc.(Just a tip,the better Chinese powertools come packed in a folded cardboard box)

They have a different way of looking at quality control from what I have seen.The price per unit they pay is the same regardless of quality in a given lot.However if they grade they can now sell the top tier for more than the bottom.Instead of making a %150 return they can now expect several times that from the same lot on the top tier units.In additon most American companies will sort to a given spec and reject or rework an item that's not up to par.Not particulary so in China,they will grade and group and then haggle price,but all units that function to some extent will leave out the door.

The prices they pay in China for the average 4-1/2" side grinder is insane,you can't get a burger and fries here for what they pay for a grinder there.That is them and not us thou(it helps to be Chinese).

By grading they have two lines of grinders,one that retails for $19.95 and another that sells for $39.95 even thou both came out of the same lot.

Another example is a local company that imports ceiling fans.They buy them by the container load and grade them.The better units show up at several of the big box stores and home centers,the junk goes to the local scrapyard.I can tell when they have finished grading a lot by the dumpsters of diecast blade holders and brass plated motor covers that show up at the local scrapyard.

Now mind you they don't check each and every unit,they just do random sampling in a given lot the same way we do.The theory being that most units in a given lot will be indentical manufacture since most factories making that type product are mostly automated except for assembly and packing.

Packaging is one of the're biggest headaches.A fan maybe perfectly well made and capable of running for years,but the packer may have not put in the instructions or the three pound bag-o-screws the end user needs to assemble the fan.This results in a busy customer service hotline.

lazlo
10-21-2007, 11:30 AM
Most of the importers we deal with are first or second generation Chinese.One in particular imports powertools and re-labels them here,they do thier own in-house grading as not all Chinese vendors are 100% honest in thier assesments.The main grading is insulation strength,the motors are megged,if they meg out above 1,000volts they fall in the top tier,second tier is 600volts and third is 600>(parts machines)These grinders look identical.but the "brand names"(peel and stick labels) on them are different as is the selling price.The percentages will vary from what I used as an example,but it is not uncommon to see several "brands" rolling out of Chinese assembly shops.

Great post Weird!

Folks over at CNCZone make a big deal of red versus blue versus green machines, but like you say, many of them are coming from the same factory, with varying degrees of post-manufacturing quality control.

Here's another picture from the Sieg factory showing the various colored machines:

Chris Wood's caption:
Mini mills to be. Different colors are for different customers.

http://www.littlemachineshop.com/gallery/images/2004-06%20SIEG%20Factory%20Tour%20China/PICT0328.JPG

wierdscience
10-21-2007, 11:43 AM
I was thinking about this statement as I have seen it used when discussing cheaper brands. I was wondering how many people use cheap import gauge blocks to test their cheaper mics. And how many will trust what they find. In the same frame of mind of cheaper imports being flawed how can you trust the gauge blocks?

Truth is you have no way of knowing if your China or US MADE guage blocks and meauring tools are working on the flush or if the provided standards are flush.

This is why NIST and calibration shops exist,they supply and compare your tools to known excepted and standards and tests and certify the accuracy accordingly.You can send your tools out and have them calibrated once a year if you like,but that costs more than most HSM's can justify.

So what's left?Well if you have multiples of given tools like micrometers,and your confident that they are of decent accuracy you can grade on average.If all three of your 1" mics agree that a given jo-block is .9995",then chances are it is,at least at the ambient temperature in the room your in.

There are also common readily availible objects that make excellent refrence standards.The most common are ball bearings and bearing balls.A collection of single bearing balls to 1" od are pretty cheap and very accurate.

http://americandad.biz/gradechart.htm

I use the grade 25 since the diameter tolerance is good enough for 99% of what work will be done.

I use a few good quality ball bearings to preset things like inside mics and ID jaws on calipers.Tolerances are down to .0001" or less and a $10 ball bearing is cheaper than a ring guage.

cybor462
10-21-2007, 11:56 AM
First I gotta mention that mode of transportation in the window in that pic. I guess not all Chinese have got cars yet! :o

Getting back to this great discussion,, weird thanks for that lesson. It parallels what I was told by Grizzly buyers. Their story puts them at the upper tier for actual machines. I was told they cherry pick at the factory. Their tooling on the other hand has a lot to be desired. I will not buy it anymore.

I can say that HF is on a much lower tier to Grizz as although the machines look identical, fit and finish, smoothness of movement of controls, and engagement is where I find a major difference.

I also agree with the power tools. I remember guys selling those grinders you talk about on ebay for $4.95! They must have been the rejects that someone got their hands on. I heard they would burn up real quick.

Another way I found you can tell is by looking at the quality of plastic. It seems the real cheap almost transparent plastic is used on the worst stuff. The better looking orange color stuff seems a little better but I would never own it. The darker colored dewalt copies seem to be a better tool.

What do you think?

cybor462
10-21-2007, 12:05 PM
This is why NIST and calibration shops exist,they supply and compare your tools to known excepted and standards and tests and certify the accuracy accordingly.You can send your tools out and have them calibrated once a year if you like,but that costs more than most HSM's can justify.







When I worked in the Gov. Aircraft shop they sent our measuring devices out monthly for re-calibration, with some going out weekly.
If we dropped or whacked any we were suppose to turn it in. Most did not. When we were given a job we had the print and then went to the tool crib where we got all the tooling and measuring tools for that part. When we were done they all were turned back in. This is how they kept up with QC. on the tooling and testing tools.

wierdscience
10-21-2007, 12:26 PM
First I gotta mention that mode of transportation in the window in that pic. I guess not all Chinese have got cars yet! :o

Getting back to this great discussion,, weird thanks for that lesson. It parallels what I was told by Grizzly buyers. Their story puts them at the upper tier for actual machines. I was told they cherry pick at the factory. Their tooling on the other hand has a lot to be desired. I will not buy it anymore.

I can say that HF is on a much lower tier to Grizz as although the machines look identical, fit and finish, smoothness of movement of controls, and engagement is where I find a major difference.

I also agree with the power tools. I remember guys selling those grinders you talk about on ebay for $4.95! They must have been the rejects that someone got their hands on. I heard they would burn up real quick.

Another way I found you can tell is by looking at the quality of plastic. It seems the real cheap almost transparent plastic is used on the worst stuff. The better looking orange color stuff seems a little better but I would never own it. The darker colored dewalt copies seem to be a better tool.

What do you think?

Yup,the quality of the plastic is a good indicator.The cheaper powertools have the hard brittle plastic that is usually thin.The better stuff has the softer,tougher plastic that feels almost like a hard nylon similar to the stuff Bosch and the like use.

Hehe the $4.95 grinder,here's a shocker,even at $4.95 the mark up is more than %100,factoring in transportation and import costs they paid less than $2 each:D

We got some that costs us $8.25 each and were going to sell them for $15 to the folks that grind the occasional lawn mower blade.I checked one out,the minute I hit the switch about 20 seconds later the gears in the head started stripping.I took it apart just out of curiosity and the 6202 ball bearing they normally use had been replaced with a cast iorn bushing:eek:I'm betting they megged out soo low that I was taking my life in my hands by holding it:D Needless to say,those went back.

ADDED:They knew the grinders where crap ,but actually made the CI bushing to the same dimensions as the ball bearing.

wierdscience
10-21-2007, 12:35 PM
When I worked in the Gov. Aircraft shop they sent our measuring devices out monthly for re-calibration, with some going out weekly.
If we dropped or whacked any we were suppose to turn it in. Most did not. When we were given a job we had the print and then went to the tool crib where we got all the tooling and measuring tools for that part. When we were done they all were turned back in. This is how they kept up with QC. on the tooling and testing tools.

Yes,that's pretty much it.We looked at some work through the GSA making replacement spares for tanks and tracked vehicles we (USA) sold to other governments.We turned it down after seeing that we would have to maintain an inspection lab,temperature contolled shop and paper trail,just wasn't worth it.

Sad thing was a lot of money could have been made since most things were like track pins and clevis bolts where chopping off roundbar and drilling crossholes was the bulk of the work.Leave it to the G'mint to complicate a part that gets beat in with a maul out in the mud:D

oldtiffie
10-21-2007, 05:33 PM
When I worked in the Gov. Aircraft shop they sent our measuring devices out monthly for re-calibration, with some going out weekly.
If we dropped or whacked any we were suppose to turn it in. Most did not. When we were given a job we had the print and then went to the tool crib where we got all the tooling and measuring tools for that part. When we were done they all were turned back in. This is how they kept up with QC. on the tooling and testing tools.

Good post Cybor.

As you say, that is QC (Quality Control).

I have been the Government "client" in these circumstances and QC was vital. Part of the QC required that the "Supplier" (Contractor) be Quality Assured to AS/ISO 6000/9000 series and had to be regularly audited by the Certifier.

All the Suppliers measuring equipment (and a lot of other stuff, including personnel qualification and training etc.) - and records and record-keeping had to be certified to be in accordance with Standards - by a NATA (National Association of Testing Authorities) on a regular prescribed basis and subject to audit as well. Any certified item that MAY have been caused to be out of tolerance had to be "re-done". Everything had to be "in date" as regards records and calibration etc. If it was not it could not be used.

The Supplier had to assure the Client that all work was completed as per Contract and Standards and supply paper and/or accessible computer records to the Client and for Audit by the Certifier.

This way the Client had assurance that work required to be done was done - as required.

The better Suppliers accepted it as they had their own "in-house" checking and auditing of their employee and sub-Contractor performance. The lesser "Subbies" and some Supplier employees hated it and went to considerable depths to avoid or circumvent it. But they were almost invariably caught out or "dobbed-in".

Breach of QA was a clear breach of Contract and could be used as evidence in seeking or pursuing those "remedies" as provided or allowed (for) in the Client/Supplier (Head) Contract.

We had copies of all Contractor QA manuals (and revisions to it) and records of work done and calibration of specified equipment and results of independent Audit.

You may think that it is all a big PITA - and often it is - but not always.

Much of the performance required was critical and the only evidence of it being provided was the material/records provided by the Supplier.

I guess that YOU would want to be assured that - say - the Medical Practitioner (including Specialists and Laboratories and Hospitals and the like) were "spot on" in this regard with respect to the equipment they were using and that they and you are relying on in what may be a critical result or procedure.

Sure, this level of assurance is costly - very - and is usually reserved for "Government" and "big" Contractors and Suppliers and the like.

For very obvious reasons lack or inadequacy of QC can give rise to some of the concerns expressed in this and some other similar threads.

But how many times have you had complaints about a product or service that you deemed or thought was "(lack of) Quality/Assurance" related? Car? Boat? Electrical goods? Work-shop tooling/equipment? etc. etc.

In the QA chain there are "Suppliers" and "Customers" - some are both (ie those that buy a product or service as Clients and in turn they (re)sell it on as a "Supplier" to their "Client" (Customer) - until it gets to the ultimate/end "buyer" (Customer).

The "chain" is not too dissimilar to the Value Added Tax (VAT) or in our case in Australia, the dreaded GST (Goods and Services Tax) where record-keeping is essential. Keeping records etc. "costs" but not as much as not keeping them does when the (usually Taxation Department) Inspectors arrive and want to see your records.

And did I mention "Lawyers", Court actions, "Claims" etc. and the records that they are after to catch you out and the same records that you are going to have to rely on. "Not knowing" is neither an excuse nor a defence.

And the costs to your reputation and the embarrassment when you are "caught (out)" for having no or incomplete and reliable records?

Seem familiar? It should.

I hope this helps.

oldtiffie
10-21-2007, 06:49 PM
Actually, I had to re-read your post Tiffie, because you edited your post to tone-down the "Sour Grapes" comment in response to Marc's comment about his bad personal experience with the quality/accuracy of the Chinese micrometers.



Tiffie, we all have Chinese (or Taiwanese) tools in our shop, so we're all very well aware of the price/performance tradeoffs, and no one is disparaging anyone else for buying, or using, Chinese tools.

But after a dozen or so recommendations from other HSM'ers for Starrett, Mitutoyo, Brown and Sharpe, NSK, Lufkin, VIS, you posted the opinion that the Chinese micrometers you got from LMS were fine, and "as good as it gets" (your words), and that the advice from the others for Western micrometers was "Sour Grapes."

Thanks lazlo.

First of all, I did not edit nor tone down my comments as you say. My edit was for minor typos etc. I said "some" others.

But its a minor point.

Now onto why I buy what I do where I do.

I have a very good look around for the tool or material that I want as regards suitability for intended purpose.

Then I go looking to see which supplier/s has/have it.

But - and this is a bit "but", I have my "preferred suppliers" whose Quality Assurance, past performance, reliability and service are "knowns" of required and consistent performance based on my past experience and that of others whose opinions I respect and rely on.

I look at the price of those preferred suppliers ONLY - no others - and if the price is OK I buy it.

I am quite prepared to and expect to pay a premium for this level of service - some-times a LOT more than what may (or may not) be "junk".

Source of product or the conditions under which it might or might not have been made or supplied are of no interest to me.

The "Starret"s "B&S" and the like are likewise judged on cost and performance at the level I require for the work that I do in my shop.

I rely absolutely on the professionalism, QA, and integrity of all of my suppliers - in other words their "Quality Assurance" to me. I pay the "going rate" that they ask. Their advertised product and price is in fact an "offer (to "treat")" which I have the absolute right to accept or reject.

I have 5 main suppliers - all of whom are absolutely first class in all respects.

They are (not in oder of number of purchases or cost/price etc.): my main supplier in Australia, LMS (USA), CDCO (USA), a tool shop about 30 Km from here and another that is about 50 Km away.

And FWIW, the USA suppliers and their product range are excellent (in fact all of them are). And if you think that my "end cost" is what I pay a premium for in the USA - think again as the "postage" costs are - to put it mildly - "considerable" to Australia. But it is all a part of my assessment of (net) "cost" in my "value for money" evaluation of the product and services provided.

I would be remiss if I did not complement the US Postal Service (USPS) as they are magnificent - could not ask for more or better.

I will assume that you are aware of the content of the LMS and CDCO catalogues.

They DO have American-made product on offer - "Starret" etc. included as well as other US manufacturers. I don't buy the "Starret" etc. solely because of cost (absolutely no question about their quality - its "tops"). But I have bought quite a bit of the similar but lesser priced US products and they are really really good both in absolute terms and in what I want them for and the the price I pay.

As a general statement, I buy "new" as opposed to "used" (or "abused" or "pre-loved" - or what-ever). If I can't see it, I don't buy it unless it is from one of my preferred suppliers or because of a recommendation from a person or persons whose expertise and integrity I respect.

I have neither right nor reason to adversely comment upon (n)or critise anybody else as to how or where or why they buy anything or its source/s.

I (think reasonably) expect no more and no less from or by others.

But - a caveat.

I will accept and give due consideration to any well-meaning, constructive, objective (and) focused advice that I get from any source - especially from the members of this forum.

And yes, you are very much included in this category as I very much respect your advice if it is within these parameters - which, I can say, it often is.


I hope this helps.

Philt
10-21-2007, 08:01 PM
"Chinese mics I have had a few as well as some calipers mostly dial types,but I did not buy them from HF as not all China measuring tools are created equal.If you see a 1" mic for $7 it's not going to be very accurate I can almost guarranty because I know for a fact that Chinese factories"grade" product and do sell seconds at a discount.This is true of powertools and electric motors.

I had a 1" mic I bought from KBC,China cost $25 way back when and I still use it for a throw around mic.I checked it with a set of gauge blocks and found it good to .0001" over the entire range,good enough.I checked about six of the $8.95 Kits,HF and a few others mics and found them to be all over the place,one came in .0001",but the rest ranged all the way up to .002" out at maximum reading."


I must be luckier than you when it comes to buying Chinese made micrometers. I was curious to see how my $7.00 "Aerospace" mic compared. This mic was purchased 5 or 6 years ago (one of the first purchases for my shop) and has been used quite a bit. I used gage blocks to check every .100" from .1 to 1" and I was surprised how accurate it was. Never was more than .0001" off. I also checked a 2-3" Chuan brand mic (proudly made in the PRC) that I purchased from JTS a couple of years ago for $8. It was also spot on every reading from 2.1 to 3.0".

Now that I am doing work on the International Space Station and nuclear submarine subcontracting using my HF 12 x 36 lathe and mill/drill in my home shop, I find it handy to be as accurate as possible. We all know how important .0001" can be!

wierdscience
10-21-2007, 10:31 PM
Luck has everything to do with it.The rest of the batch made with yours might have been good too,the next batch might might not have been.

Given some of the machinetool mfgs built lathes and mills with metric leadscrews and inch dials it wouldn't suprise me if some mics were built with inch thimbles and metric threads.But who would know unless they checked?

John Garner
10-22-2007, 11:52 PM
Philt --

Your method of checking your micrometer only checked whole revolutions of the spindle, but doesn't check partial revolutions to see if the thread is "drunken", and it doesn't verify that the jaw contact surfaces are in a plane that is perpendicular to the screwthread axis.

Checking the orientation of the jaw contact surfaces relative to the spindle axis is easy. If the micrometer correctly measures two reference artifacts that are half a spindle turn different in thickness (in other words, 0.0125 inch for the majority of imperial micrometers, 0.25 millimeter for the majority of metric micrometers), it's ok.

In our home-shop context, checking for measuring thread drunkenness is equally straight-forward but a bit more time consuming. Thickness gage leaves make a decent practical standard, and measuring every leaf from 0.001 inch through 0.025 inch only takes 10 minutes or so.

Then, for what it's worth: The Chinese micrometer threads I've seen are generally accurate but are often, perhaps even usually, banged up from mishandling before assembly. The damage, at the crests of the thread, makes it impossible for the male thread to correctly fit the female. I've "fixed" dozens of these micrometers by simply stripping the spindle and chucking the unthreaded portion in a collet (or even a Jacobs-type chuck on a drill press) and honing the major diameter of the thread with an Eze-Lap medium grit diamond sharpening stone . . . stop honing when the hone stops clicking on the bumps. Follow with a half a moment with ultra-fine Scotchbrite-type or Cratex-type to remove the microburrs left by the hone.

The female thread often needs a bit of work also; they aren't very well deburred. A few moments with a sharp hobby knife, a good spritzing with spray-can carburetor cleaner, and a couple drops of sewing machine oil followed by a snugging of the clamp sleeve on the cleaned-and-oiled micrometer spindle works wonders.

John

ckelloug
10-23-2007, 12:45 AM
I can't vouch for Chinese micrometers but I can say that the HF 6 inch calipers are not bad. I purchased a set of the calipers down at harbor freight and tested them against my set of B89-0 Starrett Gage blocks with Starrett Webber NIST traceable calibration certificate 07-47943A-F: Jan 24, 2007.

While I can't say that my measurement technique was perfect, my results at 220 points near .1000 1.0000 2.0000 3.0000 4.0000 going up from the shown measurements by .1001 through .1009 indicate that these calipers are accurate to within .0011 inches from 0 to 4 inches. Data at 4 inches is only a few points and data >4 to 6 hasn't been completed yet.

Linear regression of the 220 points shows that the measurement is modeled by
y = -0.00024368 + 0.00019278 * x where x is the gage block stack height assumed to be exact. Thermal effects of body heat were not accounted for but room temperature was verified by the house thermostat at 72 F and both the instrument and the blocks had acclimated at the start of testing. Cotton gloves were worn throughout the handling of the blocks.

What I can say about the HF calipers is that due to the feel of the blades that it was much harder to tell that they had been closed correctly on the block than it was for measuring the block with a set of 8 inch Starrett 123 Master verniers.

While the digital HF calipers were accurate to .0011 and the .0005 readings would be more or less accurate, I'd be a lot more comfortable trusting the verniers as it was absolutely certain when they were properly closed on the block. While the verniers make it hard to estimate the .0005, they are a lot more likely to get the .001 correct due to the better instrument feel.

In short, I can't see a reason to malign the chinese HF calipers as inaccurate as they really weren't but if I had a critical measurement (is there such a thing with calipers?), I'd rather have my hands on an instrument with a better feel to know they're closed. Better yet, I'd rather use a quality micrometer. I know this doesn't directly pertain to micrometers as being discussed but I hope it gives an idea of the tradeoffs between two supposedly accurate instruments.

Credit goes to Rick Sparber for getting me started on this. YMMV and individual instruments will vary.

--Cameron

oldtiffie
10-23-2007, 01:04 AM
Hi Cameron (ckelloug).

Welcome back!!

I missed your very focused a professional posts as I learned a lot from them. Your reply to this thread is just such an example. Thanks.

Any news from Rick Barber?

If you are "listening" Rick, please let us know how you are. I miss your posts too as I was looking forward to progress, comment and advice on your "cube" and "caliper" threads. I can't say I blame you at all for "giving it a miss or away" as some of the entirely unwarranted "flames" you copped were very hurtful and very embarrassing to some of us. I'd like to see you back as you make a real contribution and a damn lot of sense.

Things really "moved" when Cameron, Rick and Marv Klotz were active together in a thread.

ckelloug
10-23-2007, 11:05 AM
oldtiffie,

Glad to see you back here too. I was afraid you'd gone for good after the big flap a while back.

I've been a touch busy: I'm building a shop, taking the first of two engineering license exams Saturday(the FE), buying a commercial building, switching from military industrial complex work to software support for fracture physicists, keeping the lawn mowed etc. There is now a flexural test machine on my kitchen table and obscure titanates and silanes in a hazmat pail in the kitchen corner. I'm doing serious R&D on epoxy granite over on CNCZONE. In short, I'm about to the point of needing to schedule breathing.

Rick Sparber is alive and well although he is also rather busy according to the e-mail I got from him the other day.

Regards all,

Cameron

lazlo
10-23-2007, 11:20 AM
these calipers are accurate to within .0011 inches from 0 to 4 inches. Data at 4 inches is only a few points and data >4 to 6 hasn't been completed yet.

That sounds about right Cameron -- the HF published tolerance for their calipers is +/- .001 from 0 to 6 inches.

oldtiffie
10-23-2007, 11:57 PM
oldtiffie,

Glad to see you back here too. I was afraid you'd gone for good after the big flap a while back.

I've been a touch busy: I'm building a shop, taking the first of two engineering license exams Saturday(the FE), buying a commercial building, switching from military industrial complex work to software support for fracture physicists, keeping the lawn mowed etc. There is now a flexural test machine on my kitchen table and obscure titanates and silanes in a hazmat pail in the kitchen corner. I'm doing serious R&D on epoxy granite over on CNCZONE. In short, I'm about to the point of needing to schedule breathing.

Rick Sparber is alive and well although he is also rather busy according to the e-mail I got from him the other day.

Regards all,

Cameron

Hi Cameron.

Glad to see that you are working at "full tilt" in "48-hours work in a day" routine as usual.

How did the work-shop construct and fit-out project go?

Thanks too for the usual detailed report on the calipers as it actually verified an "advertised/claimed" performance by a distributor - in fine style.

I don't want to impose on your considerable skills in this area, but I'd appreciate it if in the not too distant future if you could see your way clear the run a similar analytical process over a selected types and range of micrometers. If not - no problems. Well, with all this idle/spare time you have!!

IIRC you have been dedicating a lot of effort over quite a time on that epoxy-granite research. Winning? Will the EG work as for natural granite - ie as in "surface-plates/reference surfaces" etc. Can you post a link top it on the CNC Zone BBS?

I am really pleased that Rick is OK. I'd like to see him back if and when he can spare the time as that "machine a small cube" was a classic as regards an analytical and practical approach to precision set up and machining on a small bench-top mill. When you email next, please pass on my best wishes.

Me? Yep, I did have a "time out" as I was getting a bit too narrowly focused and aggressive - so I took time off and took stock of myself (not too bad, but not a pretty picture in some important parts though). Too much of the "war Horse" syndrome (or what-ever it is). I could sniff the blood and cordite - and away I would go - "last man standing stuff". But its OK now - I think. Too much "Irish" and "Killkenny Cats" genes/stuff??

ckelloug
10-24-2007, 03:19 PM
Hi Cameron.

Glad to see that you are working at "full tilt" in "48-hours work in a day" routine as usual.

How did the work-shop construct and fit-out project go?
[Quote]

With only 24 hours in a day, it's glacial. I'm busy skim coating the concrete board I used as the wall covering per Evan's suggestion. With an average of 0 hours a day available the last few weeks, I've been astoundingly under productive.

With the help of my dad who was visiting, the 200 amp wires are run into the shop and over to where they'll connect to the mains but I haven't had time to actually finish installing the boxes and redo the electrical service connection to make it operational. The 2inch steel conduit install passed the building inspection so that's one less item.

[Quote]

Thanks too for the usual detailed report on the calipers as it actually verified an "advertised/claimed" performance by a distributor - in fine style.


I'm not done yet. I actually started writing a paper on modeling the error with Rick and I intend to collect data over the full range as my schedule dropes from 110% packed down to the high %90's.




I don't want to impose on your considerable skills in this area, but I'd appreciate it if in the not too distant future if you could see your way clear the run a similar analytical process over a selected types and range of micrometers. If not - no problems. Well, with all this idle/spare time you have!!


I'll look into this but the only micrometers I have in stock are a brand new Starret from e-bay and two beaten to hell old starrets also from e-bay. Come January or so, I might study micrometers if anybody on this side of the pond wishes to loan me some of the models under consideration.




IIRC you have been dedicating a lot of effort over quite a time on that epoxy-granite research. Winning? Will the EG work as for natural granite - ie as in "surface-plates/reference surfaces" etc. Can you post a link top it on the CNC Zone BBS?


The link to the huge group of us working on epoxy granite is here:
http://www.cnczone.com/forums/showthread.php?t=30155&goto=newpost

Registration is required to see the pictures however.



I am really pleased that Rick is OK. I'd like to see him back if and when he can spare the time as that "machine a small cube" was a classic as regards an analytical and practical approach to precision set up and machining on a small bench-top mill. When you email next, please pass on my best wishes.


I'll see if I can get him to come back. It's often getting started on the impossible task that actually solves something.



Me? Yep, I did have a "time out" as I was getting a bit too narrowly focused and aggressive - so I took time off and took stock of myself (not too bad, but not a pretty picture in some important parts though). Too much of the "war Horse" syndrome (or what-ever it is). I could sniff the blood and cordite - and away I would go - "last man standing stuff". But its OK now - I think. Too much "Irish" and "Killkenny Cats" genes/stuff??

OldTiffie,

I think you're one of the gems around here. All of my best to you and everybody else from the 32 year old here.

Regards all,

Cameron

oldtiffie
10-24-2007, 07:49 PM
..............................
..............................
With the help of my dad who was visiting, the 200 amp wires are run into the shop and over to where they'll connect to the mains but I haven't had time to actually finish installing the boxes and redo the electrical service connection to make it operational. The 2inch steel conduit install passed the building inspection so that's one less item.

.....................................
.....................................
......................................

I'm not done yet. I actually started writing a paper on modeling the error with Rick and I intend to collect data over the full range as my schedule dropes from 110% packed down to the high %90's.

.......................................
....................................
..................................

I'll look into this but the only micrometers I have in stock are a brand new Starret from e-bay and two beaten to hell old starrets also from e-bay. Come January or so, I might study micrometers if anybody on this side of the pond wishes to loan me some of the models under consideration.
........................................
........................................
............................................

The link to the huge group of us working on epoxy granite is here:
http://www.cnczone.com/forums/showthread.php?t=30155&goto=newpost

Registration is required to see the pictures however.

.................................................. ..
.................................................. ...
I'll see if I can get him to come back. It's often getting started on the impossible task that actually solves something.

.................................................. .......
.................................................. .......

All of my best to you and everybody else from the 32 year old here.

Regards all,

Cameron

"Edited" by oldtiffie.

Thanks Cameron - heaps.

That "get the shop done" stuff and the time it takes is only exceeded by the time it takes to do that blasted "round the house" stuff - according to SWMBO. She's a bit hard as some it (a lot of it actually) takes years. The "Yes Dear, I want to get it "just so" for you" bit is wearing a bit thin as some of it hasn't even been "thought about" let alone started or finished - for years. She's none too subtle in "reminding me" either. She is fairly patient but cannot see that the "shop" needs so much attention (all of it according to her!!). But seriously though the situation is not THAT bad - but its close - and she really is terrific.

I am looking forward to that paper you are doing with Rick as I remember the earlier editions of it. I really appreciated the principles, analysis and practical applications in it. I could quite understand it if Rick told us (me?) to ........ well ................. "use it as a suppository" (my words - not Ricks - of course -coarse(??)). But I hope not as I am sure that most are (now??) "well behaved" (my words again).

I am sure that there will be LOTS of interest in your analysis of "micrometers" - as you did for "calipers" as it laid some hoary old fallacies to rest and beautifully illustrated the need and value of high-grade professional structured, focused and impartial analysis and reporting. I am likewise sure that you will get lots of assistance as you require (micrometers etc.) as you may require from the members of this forum. Just if and as you can.

I went to the CNC site (I am a non-contributing member - as they keep reminding me!!! - Geez they sure do "nag" -but its my fault - again). It is a great read. Would it be difficult to make up and machine as a stable flat reference surface that is adequate for a small HSM shop - say as a "marking out" table and "fair to rough" surface plate? I use scrap pieces of fairly thick laminated toughened "float glass" from my local friendly Glazier who tells me that the molten Tin (metal) the glass is "float-casted" on has a dead flat surface in its molten state and that quite a few motor bike repairers use it with a sheet of "wet and dry" to hand-grind/lap cylinder heads. I find the surface quite adequate for my "surface plate" needs. But there was another real hidden gem in there as well. It said that epoxy granite does not need to need to have a "first cut" and then left for say 6 months to have it self-stress-relieve itself as cast iron does in mills lathes etc. before final machining. That makes a LOT of sense. But it is the first time I have seen it in print since my "Metallurgy/Properties of Materials/Heat-treatment" classes as an Apprentice over 50 years ago. It said then that car engine castings were pre-machined, left out to weather in the yard, re-machined and put out to weather again and then a 2-stage final machine and fit - Rolls Royce I think was quoted as one. IIRC correctly the castings were "improved" by workers urinating on the castings when they were "out in the yard". True - really!!!!

If you want a smile and why I use the "Kilkenny Cats" bit - and given that I am Irish on "both sides" (Dad's people from "South" Ireland "Mick's" and Mum's from "South" "Prods" who were forced to flee (by the "Micks") to Scotland) and my PTSD (yep. I've got that too - Navy and my genes??) and "street-fighter" attitude and past) then read this link - its a classic - and will support why I use the Phrase "(fighting like) Kilkenny cats":
http://en.wikipedia.org/wiki/Kilkenny_cat

And last and by no means least - I wish you all that you wish for your upcoming licence tests.