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hardtail
04-17-2010, 12:34 AM
I'm looking for a DBG in the 2-6" range with .0001" accuracy and was wondering if any of you had purchased this Shars unit or any recent Shars tools lately and had any comments to share. I'm sure for this price it's offshore and I would probably be better off buying a good brand name but likely wouldn't use it much, however accuracy doesn't care about that........LOL

http://www.shars.com/products/view/8084/146quot_Dial_Bore_Gage_0001quot

I see MSC has a similar Mitutoyo for $319, that was more than I was wanting to spend but still not outrageous.......now how much are they're coupons worth off?

oldtiffie
04-17-2010, 02:15 AM
I bought this one from Littlemachineshop.com:
http://www.littlemachineshop.com/products/product_view.php?ProductID=3708&category=1310310429

It cost US$70 as apposed to Shars US$145:
http://www.shars.com/products/view/8084/146quot_Dial_Bore_Gage_0001quot

While mine calibrated to 0.0005" - and not to 0.0001" as the Shars tool is.

I am quite happy with mine and would have no problem measuring to 0.0002" at least.

There is a lot of skill required to both set up and to measure with those units. I use slip guages to set mine up in preference to using a micrometer. In the case I use, the bore guage becomes a comparator instead of a measuring device or tool.

There are not a lot of bores that need to be closer than 0.01mm (0.0004").

I reserve the bore guage for deep bores as I prefer to use a "stick" or an inside micrometer as I get a better "feel" than with a bore guage.

http://i200.photobucket.com/albums/aa294/oldtiffie/Sketches/Stickgauge1-Rev1.jpg

http://www.cdcotools.com/item.php?itemid=453

http://i200.photobucket.com/albums/aa294/oldtiffie/measuring/Insidemic25to50_1.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/measuring/Insidemic50to300_1.jpg

These digital calipers are accurate to 0.01mm (0.0004") but are complicated to set up - but work well:
http://i200.photobucket.com/albums/aa294/oldtiffie/measuring/Digital_caliper1.jpg

I can easily hold 0.0004" (0.01mm) with a micrometer and spring calipers and ball and telescopic guages - and I can hold 0.0002" (0.005mm) with a bit more effort and concentration.

Job, shop and measuring tool ambient temperature differences become crucial at this level of accuracy. A job in a lathe that has heated up can take quite a while to cool down to ambient (shop) temperature. There has been many a job that was "spot on" when measured on the machine but which "shrank" or "moved" as it cooled afterwards.

ptjw7uk
04-17-2010, 03:48 AM
Seems to me that the ability to display 0.0001" resolution is a bit academic without some way of knowing if you are in the centre of the bore and at right angles to the sides.
I expect the measurements get more consistant with use.
I have also seen bore measuring gauges that have 2 'skids' at 120 degree separation which I assume will give an average measurement(cylinder boring).

Peter

oldtiffie
04-17-2010, 04:04 AM
Peter,

the rollers are the two of the "120* skids" - the top anvil/spindle is the other. There is a second anvil/spindle at the top:
http://www.shars.com/files/products/303-4737/Thumbnails/303-4722E.jpg

It does work - and works quite well, but a lot of care and skill is needed.

The two "rollers" centralise it pretty well as regards "left-right" but having achieved that, the diameter is the least reading on the dial during the "rocking/forward-back" motion. It is essential that inadvertent hand/other pressures do not interfere with the measuring and positioning processes.

I am quite happy with mine to 0.0002" (0.005mm).

A "ring" is the best guage to set up to, but in the absence of a precision test ring (source of more errors if "shop-made") a micrometer or slip guages work well enough.

JCHannum
04-17-2010, 09:38 AM
Any of the indicator type dial bore gages are no better then the means used to calibrate them. While the gage might have a 0.0001" resolution, it is the standard used to set the gage that determines the accuracy of the reading.

If ultimate accuracy is required, a standard in the range of the desired reading is needed. These standards can cost more than the bore gage in some cases.

In general, the gage heads do a good job of centering, but the quality of the components is likely to go downhill as the price declines, making the action sticky and readings not as repeatable in the lower priced instruments.

oldtiffie
04-17-2010, 10:34 AM
Jim.

I agree with you 100% (I really don't which us is going to be the most surprised with that statement - I think I feel a dizzy fit coming on!!).

At best, and as you've said before, when using guages or references to set the bore guage, it is really not measuring anything as it is a comparator that compares the job to the reference. That might be a fine point but while an inside micrometer may well be a measuring device in its own right, the bore guage is not and cannot be.

Just holding the fairly long bore guage tube incorrectly can cause it to expand quite significantly. The outer tube holds the dial indicator body and the indicator plunger is inside and pretty well thermally insulated from the outer tube and relative thermally-induced significant movement is quite possible.

"Stickiness" can be a problem and needs to be guarded against. Like most (95%+ minimum) of the stuff I've bought from LMS, it works really well.

I set mine with slip guages on my surface plate (black granite or float glass - all depends!!). I have the upper slip set as a cantilever and use that or alternatively, bring the arm of the height guage down onto the stack of slips and use the underside of the height guage arm as my reference.

I did have a problem with the two roller/supports not contacting the table so I packed them evenly and that solved it.

One of the big problems with dial bore guages and inside micrometers is that they don't work too well on hole/bores that are less than about 3/4">1" deep as they need to "rock" forward and back to get the reading. Its very easy to get a false reading in a shallow hole/bore. That is where old-fashioned calipers as well as telescopic bore guages work well.

The degree of accuracy assumed in the OP is fine - but it should be accompanied by a very high level of surface finish.

If I have to bore a hole with limits less than 0.025mm (~0.001"), I really do ask myself if it is really necessary, and if it is, why it is, and if it isn't, why the hell am I doing it.

Scishopguy
04-17-2010, 12:12 PM
Hardtail...The April MSC flier has dial bore gages on sale. The 2"-6" range unit is $62.99 with indicator, case, and interchangeable tips. The order number is: UC06451744

It is an import but what isn't these days?!

philbur
04-17-2010, 12:25 PM
The photo of the Shars dial shows 0.0005" graduations.

Of course resolution, precision and repeatability are all different things. Increasing the gearing of an instrument doesn't increase the precision. Ask for the test certificate. If it doesn't have one then don't buy it.

Phil:)


Hardtail...The April MSC flier has dial bore gages on sale. The 2"-6" range unit is $62.99 with indicator, case, and interchangeable tips. The order number is: UC06451744

It is an import but what isn't these days?!

Dr Stan
04-17-2010, 12:36 PM
I just arranged the purchase of a Scheer-Tumico Dial Bore gage off Craig's List for $25. I'll need to buy the tips to get the full range, but I'm getting a quality US tool with a Japanese made indicator for about 10 cents on the dollar.

If you know how to perform a nation wide search on CL you can locate some good deals. I have also bought a US made 6" bench vice made of high strength cast steel, a Baldor 8" pedestal grinder and a Baldor 6" carbide tool grinder off CL. Shipping was a bit high on the grinders and the vice, but I ended up with new (the vice) or virtually new tools for less than half price including shipping.

JCHannum
04-17-2010, 12:46 PM
The photo of the Shars dial shows 0.0005" graduations.

Of course resolution, precision and repeatability are all different things. Increasing the gearing of an instrument doesn't increase the precision. Ask for the test certificate. If it doesn't have one then don't buy it.

Phil:)

The test certificates for most chicom instruments are printed in bulk at some location other than where the instrument was manufactured. Most consist of an ornate piece of paper with a couple of unreadable signatures stating that the instrument is certified to be whatever it happens to be.

BadDog
04-17-2010, 02:16 PM
Over time, I've morphed a lot on bore measurement. My current go-to tools vary depending on range.

For "tiny" up to 0.500, if it needs more accuracy than my Mitu Digi Calipers, I almost never reach for anything other than my pins. Dead easy, and accurate, as long as you know the bore is actually round, and preferably with the edge chamfered/broke to aid in fitting. I've got a VERY nice small bore gage pair (2 boxes) that goes from 0.060 (or so?) up to 0.880 (IIRC), complete with ring gages to calibrate each mandrel. Those are far too nice to get rid of, almost like fine jewels, but I never use them. However, I should probably sell my Starrett small hole gages and other small hole options; I never use them. Likewise I've got some Standard bore gages that do very small holes but I pretty much never use and should probably sell. The only reason I don't, is I'm terminally plagued by "what if"...

For larger bores I've got Interrapid and Mitutoyo spring arm things like shown by Tiffy. They are accurate enough for most work as long as calibrated very near the measured diameter. Generally better used more like a DTI for comparative rather than quantitative measure. I've also got the typical Federal dial bore gages from around 0.500 up to about 3", but those are a PIA and nearly useless if you don't have ring gages in the desired sizes. I would imagine the "wide range with 20 attachments" variety would be even worse. For larger bores (over 1"), which I rarely have to fool with, when it needs real accuracy, I use a Starrett tubular inside mic that is calibrated against ether an exemplar (matching bore) or gage block stack. Total PIA, but I prefer it to the Federal Bore gages, but maybe that's just my lack of training/skill.

For most day to day work in the 0.200 to 2" range, I've got a pair of common inside mics that I use.

So in summary, though I've got a variety to choose from, I basically never use them, and I would do just fine if I didn't even own a bore gage.

philbur
04-17-2010, 02:55 PM
Firstly you cannot possibly know that, and secondly at least you have a piece of paper that justifies your return of the instrument when it doesn't meet the stated accuracy. Without it the vendor can just say "what did you expect from a Chinese made instrument". Now your reply will be " I expected what is stated on the test certificate".

Phil


The test certificates for most chicom instruments are printed in bulk at some location other than where the instrument was manufactured.

JCHannum
04-17-2010, 04:54 PM
Firstly you cannot possibly know that, and secondly at least you have a piece of paper that justifies your return of the instrument when it doesn't meet the stated accuracy. Without it the vendor can just say "what did you expect from a Chinese made instrument". Now your reply will be " I expected what is stated on the test certificate".

Phil

I do know that having seen the piles of certifications all printed with the exact same information as well as the individual certificates that come with the tools themselves.

tyrone shewlaces
04-17-2010, 05:17 PM
My $.02 on metrology stuff:
For instruments that give direct quantitative measurements, I like to have as high a quality as I can afford. So I like to have Mitutoyo or the like for micrometers, ID mics, calipers, etc. For instruments which give comparative measurements like the bore gage you are looking at, test indicators, dial indicators, etc. the quality of the instrument doesn't matter in regards to accuracy, so you can fudge on quality. I just try to get something that will be smooth and durable enough to meet my requirements. Since I'm a machinist by trade, I use test indicators a lot (for example) so I still like to have a good one like Best-Test or Interapid because they will stand up to the frequent use I give them. Bore gages don't get as much use by me, so though I have some nice ones that I picked up along the way, I wouldn't mind buying a budget one if I needed/wanted one. As long as it isn't "gummy" and the needle doesn't fall off just from regular use, it should measure about as accurately as an expensive one.

But you need to know that any accuracy will depend on how well you set the thing up before you go to measuring bores. Personally, I prefer to use a gage block set to calibrate bore gages. A lot of folks use a micrometer to set them as well - it's quick and easy but (arguably) not as accurate. You need to know how accurate either instrument is though to know how accurate your bore gage is calibrated. Mics can be a little off and so can gage blocks. So if you don't already have something to set the bore gage to, then you'll have to add the cost of that to the gage. But of course you'll then have two cool tools !

Anyway, in short, an inexpensive bore gage should work fine. It's the instrument(s) you use to set them up that need to be accurate. It takes a little practice to set them too - you can't just toss them between a known distance and zero the dial. You have to know you're perpendicular to the two faces and that takes a little fiddling, which is easy to do once you get used to it. Just practice a little and get some experienced help if you have trouble.

As is true with using any measuring tool, if you feel confident you're spot-on, you probably are. If you feel a shred of doubt, it's probably off a little.

NBbrad
04-17-2010, 05:32 PM
http://www.shars.com/products/view/8084/146quot_Dial_Bore_Gage_0001quot

I see MSC has a similar Mitutoyo for $319, that was more than I was wanting to spend but still not outrageous.......now how much are they're coupons worth off?

I'd spend the extra on the Mitutoyo. $145 is way too much to pay for a discount brand indicator like Shars. Not to mention, the one shown in the link claims 0.0001" accuracy, yet its resolution is only 0.0005".

I think you can do better than $319 from MSC. Maybe try Enco. Regardless, another thing going for the Mitutoyo is the resale value. If for some reason you find yourself not using it, you could sell it easily on ebay for close to what you paid, whereas the discount Shars probably wouldn't sell at all.

J Tiers
04-17-2010, 07:48 PM
Firstly you cannot possibly know that, and secondly at least you have a piece of paper that justifies your return of the instrument when it doesn't meet the stated accuracy. Without it the vendor can just say "what did you expect from a Chinese made instrument". Now your reply will be " I expected what is stated on the test certificate".

Phil

I "can possibly" know that, at least the printed in bulk part.....

I have seen a few of those "certs". Look at them by reflected light..... the filled-in data is often, perhaps usually, very obviously NOT ink.... it looks just like the rest of the printing, melted-on toner. Even for the parts that were hand-written.

In other words, the "individual test cert" was quite possibly produced on a copier. It is thus pretty much worthless window dressing, not even amounting to a guarantee of that performance.

I have also seen asian GENUINE certs.... Mostly they are filled-in with ink, AND they often have the "chop", the stamp of the tester, also in ink, and usually in a contrasting color.

So, yes I can be quite reasonably sure that the usual cert is worthless. Not even good enough to return the POS on account of. After all, that just gets into a you say/they say argument in most cases, as you can be assumed to be less capable of accurate measurements at whatever resolution.... if only because you were incautious enough to buy the POS to start with.

oldtiffie
04-17-2010, 08:35 PM
Now we are getting to the "nitty-gritty" as regards performance - by the tool and the dealer (who is responsible for the warranty).

I've said more often than I'd like that I pay a premium for a tool or machine from a dealer that I see personally and who relies on the "Trade" and "return business" and "word of mouth". I get the "Trade" discount which makes it a bit better as regards cost.

When I buy a tool it s opened and tried at the counter with a sales person who knows his stuff and has no hesitation in replacing the doubtful item (on the very rare occasion that any fault arises).

If I find a fault after I've left the dealers premises, I ring up, tell 'em what problem is and then I bring it in. If it is faulty, I get it swapped right there and then. I quite often take my own measuring devices if needed to prove my case but the dealer will provide most if needs be.

I have no problem with mass-produced copies of certificates as so long as the certificate is inserted into the package by the maker or provider (to my dealer) and the certificate says that it mets either a national or international standard, that will do me.

Here is a case in point:
http://i200.photobucket.com/albums/aa294/oldtiffie/Vertex_Rotab_hand-book/Vertex_rotab6_8.jpg

This certificate is mass-produced and even if the right-hand column is at the maximum in all but one case, I will do me as I know what the maximum allowable errors are. So in effect if the right hand column were missing it would still be just as satisfactory to me.

For day-to-day work, just using it "as is" is quite good enough as I can and do rely on the tool being in accordance with the certificate. I don't need to know any variations from the nominal sizes etc. unless I am very fussy in which case I measure it and make allowances and/or adjustments to the set-up or the sizes accordingly.

It is no different to having a say morse taper or a drill set that is certified to be in accordance with - say - DIN????? That's enough. I want to know more I have to get the standard. Same as a surface plate or slip guages - just a certificate to say that they are to NIST or a DIN standard level of accuracy is good enough.

I don't have any sort of "controlled environment" to "metrology" standards and I'd bet that not too many others have it either.

That too suits me as I don't need that level of environment - or the hassles that go with it - and I doubt that too many others have - or need it - either.

As soon as a tool or machine is "out of warranty" (usually 12 months) the onus is on me if a fault arises. I either fix it and use it or toss it in the $hit tin and buy another and get on with life.

I am not at all concerned about finish or packaging unless it is needed for the preservation and/or function of the tool.

As long as the tool or machine does the job I need it to do, its good enough.

Its just a matter of me knowing what level of performance I really need of or from a machine or tool and getting and having such a machine or tool when I need it.

As a general rule, I don't bother to keep a tool or machine that won't do the job. It is ditched as soon as it is replaced - if it is replaced.

I have tools and machines that I might not use from one years end to the next that are there if needed. But they pay their way when they do what they have to do when called upon.

My days - or needs - to have concerns or orgasms about machines and tools are long gone.

Bore guages are firmly in the categories above - and so is just about everything else.

J Tiers
04-18-2010, 12:15 AM
Tiffie, your cert is different from the ones I refer to...... and yet it is also a fake, effectively, if not in reality.

1) the numbers in the right-hand column are at least in 3 cases, NOT at the limit.....

2) the cert bears the name stamp of two people in contrasting colors.

Now, I don't have the original to look at, and that could be printed just as much as any other , or color copied 50 at a time. or it might be genuine. But the faker, if any, who makes a cert like that, is at least trying to make it look good...... they get a B+ at least for originality.

there is another way to view these asian mass-produced certs..... if teh device passes as below the QC reject levels, they are within their rights to give you a "cert" that amounts to a guarantee of that fact. There is no law that says they must give you a chart of the errors, etc.

They could just give you a copy of the test limits, and a statement that the device passes per those.

However, a few things apply to Tiffie's piece of "creative waste paper" as well as to others of teh ilk of "faked QC reports".

primarily, neither Tiffie's , nor any other one I have seen of the "copier type" reports EVER give a serial number. Tiffie's fake report has a place for it. But nothing is there. A cert worthy of the name is a report for a particular serial numbered unit...... it refers to the condition of THAT unit...... not mine, or Uncle Harry's....

So, unfortunately, blue ink and all, Tiffie's report is no better than a common fake mass-copied piece of waste paper. There is nothing whatever to associate it with his unit.

Then also, there is no date, so no limit on the cal time...... The date would also perhaps be so long ago that teh cal would have already expired before you received and started using the thing.

Finally, the testing device is indirectly referred to, but not identified. A real cal cert has the testing device serial and model on it, and perhaps its cal expiration date.

This is all in line with asian QC... they would say, with some justification, "who cares as long as the unit DOES PASS QC?" They are happy to sell you the unit, and are dumbfounded when you want the serial written on the report for a mass-produced product. They say, "all of the units we actually sell do pass, so we provide a report that reflects that".

Really, instead of bothering with the report at all, they could just enclose a copy of the limit specs, and a statement that "unit passes all above specs", with a check mark by it, and maybe someone's "chop"....

These are low cost units...... it would be better to not try to fake out people with a fake cal cert, and simply enclose a statement that the device was tested to be within limits.

However, one can be doubtful that the particular unit ever WAS checked...... Certainly a fake cert such as Tiffie's example would not satisfy a decent ISO calibration program, no serial number. Even mics, calipers, and rules (scales, dang it!) are given a number for a real cal program.....

tyrone shewlaces
04-18-2010, 12:36 AM
You know what I really like about this site?
It's the way the OP is ignored the majority of the time so a couple guys can duke it out back & forth about stuff that doesn't answer the original question.

Personally I couldn't care much less about certs. I wouldn't trust anybody else to decide if my tools are good enough before I'd trust myself. You can throw Mitutoyo's laser metrology out the window if my personal "touch" is lighter or heavier than the guy manning the laser. I calibrate my own tools. if If a paper makes you feel warm and fuzzy, then I guess that's good for you. In my experience, certs are only good for adding to the pile of other useless paper for ISO or other corporate management systems to also feel worm and fuzzy.

It's the tools folks. Paper sometimes works for a shim.

hardtail
04-18-2010, 12:56 AM
LOL........hey that Jack Huang is a busy guy, I know I've got at least one or two certs w his sig, but hey I'm positive the results are a lil different......NOT

I did check and Enco has the Mit on for $285, better deal but as enlightened by some maybe I can get by w an even cheaper offshore budget POS instrument......and yes I'm sure Mr Huang is in their employ also........LOL

In this case the bore will be in the 3.5" range, fitting pistons w .0005" recommended clearance using this........if I can get in the .0006/7 ballpark it will be a success

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=230461070547&viewitem=&sspagename=STRK%3AMEWAX%3AIT

I think I better do some practice runs on some other cylinders first......thx guys always insightful........LOL

Incidentally while your correct the Shars as shows a .0005" in the ad, there is an asterisk stating that the pic is wrong and it is indeed .0001"

J Tiers
04-18-2010, 01:32 AM
You know what I really like about this site?
It's the way the OP is ignored the majority of the time so a couple guys can duke it out back & forth about stuff that doesn't answer the original question.

It's the tools folks. Paper sometimes works for a shim.


Paper works a LOT of teh time........ I think that cert paper is particularly good, it's metric paper, so it makes a metric shim, right? :D

Actually, I think the OP has been thoroughly answered...... Don't buy the shars, the other one is half the price and is the same unit...............
And neither one is an Intrimik, so don't get too hung up on the cals and certs, they don't mean one dang thing, you cal it yourself for the measurement.

oldtiffie
04-18-2010, 01:43 AM
I've checked a lot of the "Vertex" and other similar stuff that I have with a certification and I have to say that I agree with it. If it were not as per the "certificate" and if it concerned me, I would have good grounds to have it replaced under warranty. At least I know how accurate it should be which is more than is the case with many who buy such things "cheap" without the documentation.

QA/QC is quite another matter as it either comes with the required certification or it gets re-tested to QA/QC specs and if passed is free for use and if it fails is rejected. Very few HSM shops will need that order of assurance. I and my shop certainly don't but I do have recourse to the warranty and the dealer who must service than warranty.

As regards the bore guage, the possibly best way is to have a really good "master" or "reference" ring guage to set, calibrate and test it against - as Jim Hannum said previously.

If that procedure was adopted the "master" etc. would need to be certified to an accuracy of "one order" better than the master was being used for.

If the accuracy required of the bore guage in use was +/- 0.0001" (one tenth) the master would need to be certified as +/- 0.00001" (one tenth of a tenth) in a metrology environment that was 10 x (ie 0.000001") accuracy.

There is a very good reason why the default calibration on metric tools is 0.01mm (~0.0004") as its practical and it works.

Working to a "tenth" is more than just measuring a dimension or size as its also about the quality of the finish and in both cases you are in the zone of grinding and/or honing and lapping. When actually measuring at these levels of accuracy (+/- 0.0001") temperatures both relative and absolute between the ambient shop temperature and the temperature differential between the job and the the measuring device are crucial.

There is no certainty that a job that was on size, round, and straight when measured on the machine will retain those accuracies when it cools.

It is quite feasible and reasonable to work between limits of 0.0005" (or 0.01mm ~0.0004") but any "tighter" has some very onerous requirements.

I prefer an inside micrometer or spring calipers and a micrometer.

J Tiers
04-18-2010, 12:38 PM
If it were not as per the "certificate" and if it concerned me, I would have good grounds to have it replaced under warranty. At least I know how accurate it should be which is more than is the case with many who buy such things "cheap" without the documentation.


Sure.... But providing a fake cert is a form of fraud.... Why go to that trouble if not to provide a false sense of security that the device meets some elaborate set of limits?

You haven't got any more grounds to return the device WITH that "cert" than you do WITHOUT it.

The manufacturer (actually the importer) advertises it as having a certain set of specs..... if it meets them when new, it's good.

if it does NOT meet them, it is bad.

The fake cert you have is just a red herring or common fraud. Even if the device is NOT per that cert, AND YOU CAN PROVE IT, you got a lot of nothing to complain about..... NO recourse.

Because the importer is going to say, with very good justification, "we state the specs of the unit in our literature, and that's what we guarantee. If your unit is a little over the numbers on the cert, it's still well within our stated specification, so we will NOT replace or accept it back as defective. You should be happy that it is that far under the published specification, you got a good one there, boy."

oldtiffie
04-18-2010, 04:14 PM
Well JT,

I have got news for you.

I have had two - and only two - occasions where my "Vertex" and similar Chinese - and similar - was a bit outside specs as regards a screw, I rang ahead to discuss it, made sure there was a spare/replacement item and took it in. Its only a 90 Km (~ 55 miles) return trip and my wife and I do some shopping and have lunch while we are over there.

Anyway.

Open the box etc. to show the fault, checked and discussed, agreed that it is faulty, new item in new box got from rack/store, opened and tested to the satisfaction of both parties, he takes old and I take new item and I am on my way rejoicing.

Similar with a tilting angle plate which I knew was of less than optimal design when I bought it - as it proved to be the case. Took it back and had the credit transferred to a new tool I wanted - and I was on my way again.

Its actually cheaper in fuel for me to drive over than it is to ship it by courier - and my wife and I both have a good outing and a good lunch.

My point here is that it has paid me over time to pay a premium for good support as regards warranty and spares etc.

If I'd have bought that stuff either privately or on eBay or Craig's List I would not have had those advantages or protections - and I don't have the costs or the vagaries of "delivery" either.

I have the option and advantage of seeing and discussing a range of machines and tools for a specific application with people who not only know their job and their product line, but have it on the display room floor for me to see or try out (mostly non-powered - for OHS reasons where the public has access) as well as having a pretty god idea what others use the stuff for etc.

So, all in all, I do pretty well.

If I can take your impressions etc. as well as that of seemingly a lot of others in the USA, you are very poorly serviced in that regard.

oldtiffie
04-18-2010, 04:30 PM
''nutha wun fer ya JT.

I buy a fair bit of stuff from Littlemachineshop.com as well as the occasional item from CDCO tools (both in the USA) as well as Arc EuroTrade (UK) as well as others in Germany and Hong Kong (China). I rely pretty well absolutely on their integrity as regards product performance and delivery as its impractical - and bloody expensive!! - to send it back from OZ.

I am rarely, if ever, "let down" and am not only very satisfied with the stuff that arrives on time every time but with very good email service that all of them provide.

Now back to topic - the bore guage.

I bought mine from LMS.com - with some other stuff - and the packing was first class and the product was exactly as per LMS specs on their web page - and it worked very well.

I have my losses too, but generally I take it on the jaw or "roll with it", shrug my shoulders, put it down to a loss etc. and move on.

I don't expect to "win" every time - and I don't.

Others - you included - may do better - I hope so.

JCHannum
04-18-2010, 05:16 PM
Well JT, he takes old

And returns it to stock for the next guy. What has he got to lose?

J Tiers
04-18-2010, 06:16 PM
You CAN get good service. If you are reasonable, etc, most places will be equally reasonable.

For a good customer, even a totally bogus complaint may get accepted and serviced.....

My point is NOT that you can't get good service. My point is rather that the CERT gives you nothing whatsoever that you don't already have without it.....

You appeared to treat the "cert" as a magic talisman which has the capability to force action from the vendor..... When it is no such thing at all.

It is a "scrap of paper" worthy of Neville Chamberlain, and not much more than that.

oldtiffie
04-18-2010, 09:32 PM
Originally Posted by oldtiffie
Well JT, he takes old

And returns it to stock for the next guy. What has he got to lose?

I am not to know that, but if it happens, the vendor is taking a chance that another "me" might turn up - and then he does have a problem - as he relies on his reputation. He may just "eat" it or put it out on his "specials" table or web site - its his decision. You seem to presume that he will - he might - but I'm inclined to say that while it may happen, I have not seen any evidence of it, and unless or until I do, I give him the benefit of the doubt.


You CAN get good service. If you are reasonable, etc, most places will be equally reasonable.

For a good customer, even a totally bogus complaint may get accepted and serviced.....

My point is NOT that you can't get good service. My point is rather that the CERT gives you nothing whatsoever that you don't already have without it.....

You appeared to treat the "cert" as a magic talisman which has the capability to force action from the vendor..... When it is no such thing at all.

It is a "scrap of paper" worthy of Neville Chamberlain, and not much more than that.

What a personification of negativity you two are. The more so when anything "China" is mentioned - good or bad.


You appeared to treat the "cert" as a magic talisman which has the capability to force action from the vendor..... When it is no such thing at all.

Nope.

It is the standard by which the machine or tool is bought, sold and measured - no more and no less. It is a reference or touchstone as regards performance and dispute resolution - if it gets to that.

It avoids or negates the "as is - where is" and "because I say so" or "I was told" scenarios.

If I have a price and/or performance requirement or point, knowing what my requirements are and knowing the standard to which the tool was made makes it easier to make a realistic and rational decision, and if needed, to assist in resolving a warranty issue.

I am rarely let down or disappointed - so either my way "works" or I am luckier than most - or perhaps I don't know when I've been taken advantage of or perhaps I'm dead naive or just "simple" or I bull-$hit myself and others. Perhaps I live in "Noddyland".

Maybe so.

Never the less, that bore guage that I bought from LMS in the USA does all that was claimed for it which just so happened to meet my performance and cost requirements.

If the OP bought a similar item, I am quite confident that with due diligence and care that he can measure to +/- 0.0001" (0.0002" between limits).

J Tiers
04-18-2010, 11:09 PM
Nope.

It is the standard by which the machine or tool is bought, sold and measured - no more and no less. It is a reference or touchstone as regards performance and dispute resolution - if it gets to that.

It avoids or negates the "as is - where is" and "because I say so" or "I was told" scenarios.

If I have a price and/or performance requirement or point, knowing what my requirements are and knowing the standard to which the tool was made makes it easier to make a realistic and rational decision, and if needed, to assist in resolving a warranty issue.



Oh, if it was really a "cert" you'd be correct.....

but the 'cert" that you trustingly and credulously hold in your hot little hand does not refer to the unit you have, it just happened to be in the box with it. Perhaps it is some extra packing............... it is literally a "scrap of paper", and has no legal significance.

ONE number would change that......

If the maker had the balls to put the unit serial number on the cert, THEN it would "magically" turn into a "document", which asserts that the SPECIFIC unit in question was in fact tested, and came up with the SPECIFIC numbers shown on the "document".

THEN, and ONLY then, would you have some justification in waving the document and saying that this unit does not conform to the document.... and thus that there is a problem.

of course, EVEN IN THAT CASE, so long as the unit is within the actual limits of acceptability on the cert document (or more precisely, the limits which the maker or distributor publishes as limits), . you STILL have no grounds to bitch and moan.

You have grounds for complaint ONLY if the cert is wrong AND the actual measurements of the unit are actually OUTSIDE the acceptable limits as published by the manufacturer or distributor.

JCHannum
04-18-2010, 11:19 PM
What a personification of negativity you two are. The more so when anything "China" is mentioned - good or bad.

No negativity at all, just stating the obvious. No mention of China either. The fact of the matter is that I have, or did have, a stack of Mitutoyo certs here, all duplicates that came off the same press run.

As Jerry says, unless there is some backup information, including the instrument serial number and testing instrument information, the cert is meaningless.

Starrett and other manufacturers will offer true certification of some of their merchandise, but it will cost you extra, and not an insignificant amount either. You are not going to get that with any low end instrument or tooling.

oldtiffie
04-19-2010, 12:45 AM
Originally Posted by oldtiffie
Nope.

It is the standard by which the machine or tool is bought, sold and measured - no more and no less. It is a reference or touchstone as regards performance and dispute resolution - if it gets to that.

It avoids or negates the "as is - where is" and "because I say so" or "I was told" scenarios.

If I have a price and/or performance requirement or point, knowing what my requirements are and knowing the standard to which the tool was made makes it easier to make a realistic and rational decision, and if needed, to assist in resolving a warranty issue.


Oh, if it was really a "cert" you'd be correct.....

but the 'cert" that you trustingly and credulously hold in your hot little hand does not refer to the unit you have, it just happened to be in the box with it. Perhaps it is some extra packing............... it is literally a "scrap of paper", and has no legal significance.

ONE number would change that......

If the maker had the balls to put the unit serial number on the cert, THEN it would "magically" turn into a "document", which asserts that the SPECIFIC unit in question was in fact tested, and came up with the SPECIFIC numbers shown on the "document".

THEN, and ONLY then, would you have some justification in waving the document and saying that this unit does not conform to the document.... and thus that there is a problem.

of course, EVEN IN THAT CASE, so long as the unit is within the actual limits of acceptability on the cert document (or more precisely, the limits which the maker or distributor publishes as limits), . you STILL have no grounds to bitch and moan.

You have grounds for complaint ONLY if the cert is wrong AND the actual measurements of the unit are actually OUTSIDE the acceptable limits as published by the manufacturer or distributor.
JT.

It is my responsibility and prerogative to decide or determine what level of certification I require.

I have exercised those obligations and privileges and am satisfied with the outcome.

I am responsible for my own decisions and mistakes and I owe nobody an explanation.

But having said that, I did not - and still don't - require other than an enclosed piece of paper from the manufacturer or provider to my supplier that says what the article can do and what the limits are.

My supplier as agent for the distributor assumes the responsibility for the warranty as regards fitness for service. That paper defines the limits of the performance.

I don't see that I need - or that I said I need - "traceability" to NIST (USA) or NATA (National Association of Testing Authorities) standards here in OZ as I am not running a certified QA/QC set-up here. I am quite well acquainted with the requirements of QA/QC having been a Contract Administrator who had to ensure QA/QC performance both as a client and a provider.

There is no need for it in my shop - hence no need for "traceability".

I rely on "good faith" and "fair dealing" and I both get it and give it.

http://en.wikipedia.org/wiki/Implied_covenant_of_good_faith_and_fair_dealing

I certainly don't assume - unless there is good reason to do otherwise - that anyone that I have or may have dealings with is a thief, rogue, vagabond, ne'er-do-well etc. as I try to treat people fairly. I have found that in the vast majority of cases that I am treated fairly.

I am eternal optimist as regards the integrity of most that I have dealings with. I have had a lot of luck at avoiding those who are or may be inclined to be otherwise.

In the few occasions where things "went wrong" some were sorted out amicably, others not. I have taken some to court or had my lawyer threaten appropriate action and in the vast majority of cases have "won" morally if not financially.

I can't - and don't - say that my experience is typical of any others here in OZ, but I'd hope and like to think that it was and is.

I hope that what-ever has caused you to be as doubtful as you seem to be is not typical of those in the USA.

It seems to me that the level of complaints in the USA, and to a lesser extent, Canada, far exceeds those in the UK, Europe, NZ and here in OZ.

I just hope that the impression that I have is not indicative of the reality in the USA.

The "Neville Chamberlain" (Prime Minister of the UK at the time) and his "Peace in out time" remark with that "piece of paper" from Germany just before WW2 started, is not really relevant at all.

http://en.wikipedia.org/wiki/Peace_in_our_time.

If I were a German member of this forum, I'd be pretty pi$$ed off with that remark.

I have "pieces of paper" from German-made tools (excellent German stuff by the way) that I have never had to test the warranty of, but I can say that the service and support frpm their local arms and agents here in OZ was beyond reproach - excellent.

While this is a general statement of "where I'm at" it is 100% relevant to the bore guage in question.

oldtiffie
04-19-2010, 12:59 AM
Originally Posted by oldtiffie
What a personification of negativity you two are. The more so when anything "China" is mentioned - good or bad.


No negativity at all, just stating the obvious. No mention of China either. The fact of the matter is that I have, or did have, a stack of Mitutoyo certs here, all duplicates that came off the same press run.

As Jerry says, unless there is some backup information, including the instrument serial number and testing instrument information, the cert is meaningless.

Starrett and other manufacturers will offer true certification of some of their merchandise, but it will cost you extra, and not an insignificant amount either. You are not going to get that with any low end instrument or tooling.

Thanks Jim.

We may be at cross-purposes here as I don't require certification or traceability to NIST standards for reasons given in my previous reply to J Tiers.

My receipt for payment and the "offer" on the suppliers web page/s (pre-purchase) as well as the "enclosed certificate" (post payment) are all that is needed in my case here to meet my requirements both as regards performance and warranty issues if needs be.

We don't have anywhere near the choice of "used" ("pre-loved"??) stuff and prices that you have on eBay and the like in the USA and to a lesser extent in the UK and Europe. Its generally better to at least consider "new".

I almost invariably buy "new" and have the warranty and service that I need - so it all goes pretty well.

That is not to say that "glitches" or "misunderstandings" don't happen - they do - but rarely with me and most are easily resolved with "good faith" on both/all sides.

J Tiers
04-19-2010, 09:53 AM
JT.

It is my responsibility and prerogative to decide or determine what level of certification I require.

I have exercised those obligations and privileges and am satisfied with the outcome.

I am responsible for my own decisions and mistakes and I owe nobody an explanation.

But having said that, I did not - and still don't - require other than an enclosed piece of paper from the manufacturer or provider to my supplier that says what the article can do and what the limits are.

My supplier as agent for the distributor assumes the responsibility for the warranty as regards fitness for service. That paper defines the limits of the performance.

I don't see that I need - or that I said I need - "traceability" to NIST (USA) or NATA (National Association of Testing Authorities) standards here in OZ

of course it's your business.

Just pointing out that the paper has no meaning, and that the service you get is dependent on the good will of the dealer..... and the performance of the item vs the published specifications.

The specifications rule, IF you care, which apparently you do not.

The cert is essentially, EVEN IF it is serialed etc, just a certification that the device meets the spec, and by how much.

if you want to get better performance, and the cert shows it, all well and good, if it is a proper cert.

Warranty? Other than your dealer's good will, the cert is not important, other than as an assertion of performance within the guarantee. if performance is actually OUTSIDE the guarantee (not teh cert), there is a warranty issue.

NATA is a separate issue, and the cert forms no part of that unless traceable.... that is a side issue.

A mass-copied cert is "packing material".....

I wouldn't bother discussing it, except that the whole matter is a kind of fraud, and these "certs" should not be mistaken for the real thing.

Trying to assert the validity of one is like showing up at an accordion gig with a toy concertina.

oldtiffie
04-19-2010, 11:43 AM
JT.

In the case of the 6" "Vertex" rotary table, the test report of which I posted earlier together with the specifications - here:
https://www.machineryhouse.com.au/Products?stockCode=R006#specs

together with the statutory requirements and obligations of the supplier make it a pretty firm case - I bought mine new.

If my tool suits my needs as defined by the specification and test report, my requirements and those of the supplier are met.

I have never yet had to resort to the legalities of the warranty - or to even show my receipt/s. All is "worked out" and based on mutual trust.

My mention of NIST and "traceability" was in response to your seeing a need for serial numbers of testing equipment and the tool etc. - which is a classic QA/QC requirement.

As I neither have nor need "traceability" then it follows that I am not bothered by not having it.

My bore guage met the specification on the LMS web page at:
http://littlemachineshop.com/products/product_view.php?ProductID=3708&category=1310310429

It meets all those specifications and works very well.

It is much better as regards consistency and accuracy than the 0.0005" quoted.

I am very confident in LMS based on quite a number of dealings with them over time.

On another thread:
http://bbs.homeshopmachinist.net/showpost.php?p=542413&postcount=30
but on a similar issue as regards "buying":



Originally Posted by JoeFin
Oh but you'll buy a machine on the seller's word

99% of these Jack Arses selling crap on Eboner with a 99.9% rateing screem and cry over the phone when I call them up to tell them their listing was B.S. and I want my money back.

But then of course YOU have already paid the freight on 4000lbs of paper weight - now who would be the Idiot then


Not this boy...... I generally figure the seller for either an idiot, ignorant, or a crook.... And I look it over very well in person.

I am not an "ebay member", which has been disadvantageous, but at least I haven't got "took"...... I only have been disappointed in ONE personally inspected purchase..... and I did see that one run. it was a filer, and I thought I could fix the problem. I could, but I decided I really did NOT want to. Problem was a sloppy plunger on an ancient Milwaukee.

I sold it to someone else who I think is a member here, with as full disclosure as I could do..... he decided it would be OK for him despite the problem, and as far as I know it has been.


Not this boy...... I generally figure the seller for either an idiot, ignorant, or a crook.... And I look it over very well in person.

I can tell you that if you ever showed up here with that attitude and that chip on your shoulder - with me as the "seller" - I'd damn soon knock that chip right off - and you would get the "bums rush" aka "the ar$e" right off the property in double quick time and left in no doubt that you need not return.
http://en.wikipedia.org/wiki/Chip_on_shoulder

I just hope that in the event that you did turn up here that things would be better - in which case you would be welcome.

Arthur.Marks
04-19-2010, 11:50 AM
;) Back on topic:
Benefits/preferred application for different bore measuring devices.

I have a part that needs a precise (+0 / -.001) bore for a bearing press-fit. Really, I've only used a telescoping gauge with OD micrometer OR my nice Mitutoyo Absolute Digimatic calipers. I need to be able to measure on the lathe to calculate the finish cut.

I feel with the telescoping gauges that they always read a little under the true measurement. My general process is to eyeball centerline and hold perpendicular as best as possible. Lock. See if I have movement up or down---while still trying my best to hold perpendicular. The idea being if I do have movement, it is not the exact center and will move because the centerline is wider than any two points above/below it. I do my best, but it always seems like there is a little movement. Of course, any angular deviation from perpendicular messes it up.

With the calipers, it just feels unreliable to me. I generally find what I believe to be centerline/perpendicular, then angle left/right to see if I get a larger reading. Then move up/down to see if I get a larger reading.

I know the other option is a comparator process, but if I was to do that, I would probably just use a shop-made go/no-go gauge instead.

B&S Tri-Bore mikes are great, but for a 49.61mm bore, the price is stupendous:eek: ! Just not gonna happen.

Can my method be improved on my direct-measurement options above? What do you find to be a cost-effective direct-reading / comparator method which works best for general work to +/- .0005" or +/-.02mm measurement on the lathe---not inspection afterwards?

huntinguy
04-19-2010, 12:10 PM
I'm looking for a DBG in the 2-6" range with .0001" accuracy and was wondering if any of you had purchased this Shars unit or any recent Shars tools lately and had any comments to share. I'm sure for this price it's offshore and I would probably be better off buying a good brand name but likely wouldn't use it much, however accuracy doesn't care about that........LOL

http://www.shars.com/products/view/8084/146quot_Dial_Bore_Gage_0001quot

I see MSC has a similar Mitutoyo for $319, that was more than I was wanting to spend but still not outrageous.......now how much are they're coupons worth off?

This has been beaten to death in this post but I will add my wack.
If you want to work this close, I assume you are in a temperature controlled room and familiar with the required procedures to work this close, then: http://www.sunnen.com/ResourceDetails.aspx?ResourceID=28&ProductID=23&NavID=666 these are the people you want to deal with. I have used gauges from more manufactures than I can remember. Sunnen, to my mind have always been the best.
At this you still should use an air gauge for size and the bore gauge for cylindricity checking, even that will not tell you if you have a lobed hole. That is an entirely different checking process. http://www.tec-ease.com/tips/december-04.htm
You will also be looking at a set of gauge blocks. Here is some reading: http://www.starrett.com/pages/1338_primary_standards.cfm

In short... if you are going to work in that world... $400.00 is the first down payment.

fwiw... that link is for a .0005 gauge... something is amiss....

oldtiffie
04-19-2010, 12:18 PM
Arthur.

As your tolerance is +/- 0.0005" the limits are 0.001" apart, your suggestion of the "go-no go" guage is hard to beat for work on the lathe.

I quite often use a spring internal caliper set to just under the required bore size. The caliper can be used on the job while the job is running/turning. It saves a lot of start-stop-measure etc. and with a bit of patience and practice works very well. It won't harm the caliper if coolant (aka "suds") or cutting oil are used as they act as a lubricant for the calipers.

I have used the "stick" method for many years - it is the equivalent of a pre-set inside micrometer or telescopic guage or a micrometer test bar - and works on exactly the same principle. I can hold to 0.0004" (0.01mm) limits easily with it - give it a try:
http://i200.photobucket.com/albums/aa294/oldtiffie/Sketches/Stickgauge1-Rev1.jpg

The OP seemed to require the bore guage for "off the machine" honing where bore guage access on the job was no impediment.

I agree with you that the bore guage is more for an "off the lathe" use than on it.

krutch
04-19-2010, 02:22 PM
I have a Peabody 2-6" DBG, Mod 5750, and somewhere along the line, the 'skid' collar has been removed. I have the 'skid' collar and related springs, but the retaining screw for the collar is gone. Does anyone out there know what this screw is? Is it a shoulder screw, and what size would it be? Have emailed OEM, but on response. MSC's answer to my question is to quote for new gage. My next approch is to make my own screw and modify for that. Be easier to replace original screw.
Krutch

Arthur.Marks
04-19-2010, 02:26 PM
That's sorta funny, oldtiffie. I for some reason have always set the telescoping gauge to the bore and measured---not measured and set the gauge for the target bore :D Entirely logical, but it never occurred to me to use my telescoping gauge as a go/no-go tool.

Arthur.Marks
04-19-2010, 02:38 PM
krutch, the description is a little confusing to me. Do you mean this screw with a ball bearing on the end? http://s771.photobucket.com/albums/xx357/Arrak_Thumrs/DBG/

If so, I suggest a trip the hardware store and trying to find what fits. Then you can buy a "set-screw" with a ball bearing tip from McMaster-Carr (www.mcmaster.com) to replace it. At the web page, type in "3071" in the search. It will take you to that page in the catalog. You can see what I mean.

If it is another part, a picture would help.

Paul in OKC
04-19-2010, 05:11 PM
Didn't read all of the responses, but I have both the Mitutoyo, and Peacock brand DBG's, and both are excellent, and read in the .0001.

J Tiers
04-20-2010, 01:02 AM
Spring calipers rule...... I'd rather use them than telescope gages any day.

You can either do a direct contact measurement, OR you can do Tiffie's "wiggle method".

They stay put, they adjust sensibly, and they tend not to lie.... What's not to like?

Just make sure you get the type with the adjustment THROUGH the arms, and not on an offset bracket...... they work much better as far as stability.

Bore gages are OK but pricey..... I do have a couple dial gages like Tiffie's picture shows (the ones with two arms), also. They work OK, need to be zeroed "on" dimension.

A couple weeks ago a guy on the local Craig's list was selling the ENTIRE set of Intrimiks up to 6" or so.... about a dozen. Wanted $1500 for them which if I had been able to justify it would have been a very good deal.... new cost was more like 6 grand. But I just plain didn't need them.




I can tell you that if you ever showed up here with that attitude and that chip on your shoulder - with me as the "seller" - I'd damn soon knock that chip right off - and you would get the "bums rush" aka "the ar$e" right off the property in double quick time and left in no doubt that you need not return.


I never said that I let the seller KNOW that I consider them to be a 'used car salesman" or worse..... I can be very nice and polite and 'two-faced" when I don't feel like causing any trouble... I ain't buying YOU, I am buying the machine, so I don't care if the seller is an ass.

I just assume that it is up to me to discover what I can while being assaulted with stories about the wonderful work the machine has done, or when it was last rebuilt, etc....... Most individual sellers are into wishful thinking and often will explain about what the machine SHOULD do, and not what it really does.

It's my responsibility to discover what is right and wrong and assess the machine before I spend money on it.

I EXPECT the seller to have neglected it, patched it, and made "farm fixes"...... I have yet to be wrong, other than the mill...... Which was nearly perfect.

I have sold two machines so far. For the first one I gave full disclosure of the problem, and the buyer accepted that.

In the other case, I actually refused to sell it to two people, because I it was NOT what they wanted.... and I told them that.

I did sell it to a guy who said nothing about what he wanted, and simply paid me the asking and took it away. I hope he liked it.

I tend to be a no bullcrap type about machinery...... if it isn't going to work for you, I don't want you to buy it from me. And if it isn't going to work for ME, I won't buy it no matter what the seller says about it.

hardtail
04-20-2010, 02:26 AM
This has been beaten to death in this post but I will add my wack.
If you want to work this close, I assume you are in a temperature controlled room and familiar with the required procedures to work this close, then: http://www.sunnen.com/ResourceDetails.aspx?ResourceID=28&ProductID=23&NavID=666 these are the people you want to deal with. I have used gauges from more manufactures than I can remember. Sunnen, to my mind have always been the best.
At this you still should use an air gauge for size and the bore gauge for cylindricity checking, even that will not tell you if you have a lobed hole. That is an entirely different checking process. http://www.tec-ease.com/tips/december-04.htm
You will also be looking at a set of gauge blocks. Here is some reading: http://www.starrett.com/pages/1338_primary_standards.cfm

In short... if you are going to work in that world... $400.00 is the first down payment.

fwiw... that link is for a .0005 gauge... something is amiss....

No I am not in a temp controlled room but perhaps 1000's of mechanics and engine houses should be........LOL I would think they would shudder if the reality of daily acheiving these results were known to them and yet they do?........fail and you go to the HSM jury.......LOL

In all seriousness thx for the links and suggestions, I see a lot of different approachs to acheiving these results, I must say sometimes ignorance is a blessing........LOL

The link has the wrong photo for the ad.

Now to fill up with popcorn and back to the gunslingers........

BadDog
04-20-2010, 03:19 AM
Spring calipers rule...... I'd rather use them than telescope gages any day.

You can either do a direct contact measurement, OR you can do Tiffie's "wiggle method".

They stay put, they adjust sensibly, and they tend not to lie.... What's not to like?

Just make sure you get the type with the adjustment THROUGH the arms, and not on an offset bracket...... they work much better as far as stability.

J, do you have a tubular (or second choice, rod) inside mic? Like you, I do like the old spring calipers for both inside. But I feel more confident with the tubular inside mic, mainly because it eliminates a transfer. It would also be quite good for Tiffies rocking exercise.

I should also take a pic of my bore gages. I think they are far superior to typical 3 point systems, at least in simplicity, though each does enjoy certain benefits in specific scenarios.

oldtiffie
04-20-2010, 06:02 AM
J, do you have a tubular (or second choice, rod) inside mic? Like you, I do like the old spring calipers for both inside. But I feel more confident with the tubular inside mic, mainly because it eliminates a transfer. It would also be quite good for Tiffies rocking exercise.

I should also take a pic of my bore gages. I think they are far superior to typical 3 point systems, at least in simplicity, though each does enjoy certain benefits in specific scenarios.

Russ,

if I can butt in here.

The advantage of a "stick" or pre-set inside micrometer or telescopic bore guage (set to a micrometer or slip guages) is that it acts as a comparator. The "sensitivity" and "feel" are crucial and needs to be the same in the setting reference as it is on/in the job.

The secret - if there is one - is to "weave" the "stick" sideways as it advances. You can easily "feel" when the "stick" stops either at the side or the front. See the sketch just above the table:
http://i200.photobucket.com/albums/aa294/oldtiffie/Sketches/Stickgauge1-Rev1.jpg

I tend to make the stick about 0.0002" per inch under-size so that I am "on size" with the bore when the stick has a maximum side-ways "rock" of 1 degree either side of centre. That one degree need not be too accurate as an "eye estimate" is quite good enough.

I use my pre-set inside micrometers, spring-calipers, telescopic bore spring bore guages, ball spring bore guages the same way as it eliminates the "sticky spot" at "top dead centre" if the "stick is right on size.

I use the "rocking" feature and the "stick" to see how far I have to go to get to size. For example - using the table - a "rock" of say 3 degrees either side of centre means that I have about 0.0014" per inch of diameter to go. 5 degrees either side of centre means about 0.004" per inch of diameter to go, 10 degrees either side of centre is about 0.015" per inch of diameter to go etc.

I just make the "stick" out of anything that is handy - old rod, welding wire, a bolt etc. - nothing special - and use an outside micrometer or slip guages to set the over-all length.

It can be a bit "tricky" or frustrating at first but stick with it (sorry - not) and you might just be very pleasantly surprised at just how accurate and consistent - and easy and cheap - it can be. It requires some dexterity/manual skills as well as regular practice.

The difference and perhaps the problem with freely expanding/contracting bore device like the bore guage referred to by and in the OP:
http://littlemachineshop.com/Products/Images/480/480.3708.jpg
http://littlemachineshop.com/products/product_view.php?ProductID=3708&category=1310310429

and this pair of digital calipers:
http://i200.photobucket.com/albums/aa294/oldtiffie/measuring/Digital_caliper1.jpg

is that the "anvils" are moving all the time and there is little "feel" and its a matter of finding and noting the least/smallest figure/diameter. They work and work well but they use a different method and need a different method (from the "stick") to use them successfully.

Bore indicators with the measuring fixed and moving anvils - such as at LMS - shown above - can be set with slip guages or a micrometer and while a "ring master" may be ideal, it can be used as well.

Bore indicators with three (ie 3 x 120 degree) anvils can only be (pre)set with a master ring.

Bore guages are designed for use in holes/bores and do not work well (or if) at all in parallel slots. This item from LMS is pretty well ideal for that as quite accurate and consistent results are readily achieved:
http://littlemachineshop.com/Products/Images/480/480.2552.jpg
http://littlemachineshop.com/products/product_view.php?ProductID=2552&category=1962771978

J Tiers
04-20-2010, 09:30 AM
Yes, I do have an inside mic, the rod type. Actually two of them. But they are really comparators, the markings are only accurate if the rods are all set and adjusted perfectly.



Brown & Sharpe used to make a set of those parallels that were really FOR holes..... they had a proportioned radius ground onto the faces.

You got, near as I can tell from the catalog, a set of various pieces, and fit them together as-needed to suit the hole. I don't think there were both pieces of all sizes, but rather a couple of one, and a set of the other side.

As such, they would be accurate only in a ground hole, since of all the gages, they are the ones that will pick up the most error from high spots.

Spring calipers function like the "wiggle rod", but adjust to any size bore.

Arthur.Marks
04-20-2010, 11:13 AM
Just make sure you get [spring calipers] with the adjustment THROUGH the arms, and not on an offset bracket...... they work much better as far as stability.

Is what you mean exemplified in the image of the MX 10-30mm spring calipers in "oldtiffie's" post above? Guess I don't know really anything about this tool, having never used one.

krutch
04-20-2010, 04:10 PM
krutch, the description is a little confusing to me. Do you mean this screw with a ball bearing on the end? http://s771.photobucket.com/albums/xx357/Arrak_Thumrs/DBG/

If it is another part, a picture would help.

No, I could easily make one of those.
I hope I've done this right, so here is http://s1040.photobucket.com/albums/b406/thekrutch/?action=view&current=scan0002.jpga pict. of the assembly.
The screw of which I speak holds, through the slot, the 'skid' and springs in place. I will take your advise and sort out a screw with the threads I need at a "hardware" store. As you may know those are a joke anymore. There is only one close to me which come close to being a hardware store. However, if I can ID the size, maybe I can locate or make what I need.
Thank You
Krutch
Had thought of that before, but had hoped to find OEM screw.
Looks as though you will have to enlarge the pict. to clearly see what I am talking about.

BadDog
04-20-2010, 04:48 PM
I should learn not to post late at night when my head is not clear. <sigh> None of that came out right.

Yes, when adding extensions, you always have to calibrate. When used, I did mine with either caliper or block stack and cap-blocks from the accessory kit. But assuming accurate calibration, reading is direct and accurate to the limits of your positioning, feel, and the (Starrett in this case) micrometer head. So when used correctly, I wouldn't call it a comparator at all, unless you also label a mic in the same way. But if matching an existing bore, obviously there is no need to calibrate, and just use it comparatively...

Also, the comment about using it as Tiffie's "stick" should have had a smiley. Though true, it was a joke. :D

Reading it today, it also sounds like I am claiming to have some amount of experience with them, I don't. I've used them but mostly just as an exercise (attempt to gain some proficiency) in cases where my Digi calipers would have done just fine.

Anyway, here are my (also basically never used) bore gages that I'm rather fond of. Unlike the 3 pointers, they won't detect lobing, but they are easy to set/calibrate (having beautiful ring gages included) and very fast/easy to use/read. Nice if you are confident that the hole is round. Otherwise all you do is measure the smallest diameter.

http://img4.pixa.us/b7a/18809973_th.jpg (http://baddog.pixa.us/images/18809973/)

http://img4.pixa.us/424/18809974_th.jpg (http://baddog.pixa.us/images/18809974/)

http://img4.pixa.us/dcf/18809975_th.jpg (http://baddog.pixa.us/images/18809975/)

Click for larger images. Click again for full size.

J Tiers
04-20-2010, 11:16 PM
Is what you mean exemplified in the image of the MX 10-30mm spring calipers in "oldtiffie's" post above? Guess I don't know really anything about this tool, having never used one.


I mean items like the following. Some are made of sheet metal and have the adjuster screw on a side bracket or "button" . instead of passing right through the middle of the arm. Those tend to not adjust as well. The ones in the picture are Lufkin

http://img.photobucket.com/albums/0803/jstanley/spring_cal1.jpg

Arthur.Marks
04-20-2010, 11:20 PM
JTiers, Gotcha. I totally understand what you mean now. Thanks! :)

radkins
04-21-2010, 04:44 PM
I mean items like the following. Some are made of sheet metal and have the adjuster screw on a side bracket or "button" . instead of passing right through the middle of the arm. Those tend to not adjust as well. The ones in the picture are Lufkin

http://img.photobucket.com/albums/0803/jstanley/spring_cal1.jpg


I have been following this thread with a lot of interest and when I read the above I thought, AHA! Now I know why my cheapie spring calipers don't feel right, ok I will order some good ones right now. Got out my Enco master catalog but no luck there, everything they have is the flat leg design so I went to MSC and got the same result. Next it was Ebay but even there I could find only a couple of examples and they were really small, they were B&S but the larger B&S I found were of the flat leg design with outside adjustment. Even Mitutoyo are outside adjustment design as is all of the Starrett that I found, any suggestions on where to find the ones you describe in 6" to 8" sizes?

Arthur.Marks
04-21-2010, 04:57 PM
...any suggestions on where to find the ones you describe in 6" to 8" sizes?

McMaster-Carr. Look on catalog page 2246. They show a 6" of that design. For manufacturer's numbers look here: http://www.starrett.com/download/426_p353_356.pdf MSC/J&L has a custom quote page. They will sell you one drop-shipped if you provide Starrett's product number on the quote form. I have a couple of the friction joint calipers from Starrett and find them very nice to use. AFAIK, they are the only quality, precision toolmaker still making the basic hand-tools like this.