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firbikrhd1
11-14-2011, 05:33 PM
I have a Starrett last word test indicator that I purchased several years ago at a flea market for not too much money. It languished in my box until recently when I wanted to use it. Upon closer inspection I found that the crystal falls out easily and the indicator itself is slightly sticky. The bezel that rotates and holds the crystal is OK but rotates with difficulty and the face of the dial is warped if the bezel is removed.

I can have this indicator repaired to like new condition by Long Island Indicator for about $70 or I can purchase a new indicator. Some older posts here recommend Interapid highly but I don't know the price. Some older posts also speak about the Last Word indicators being "sticky" as one of their quirks

I can purchase, new from Enco, a Fowler for about $55, or the Enco brand for $37. Other suppliers have similar prices for their low end indicators. Money is tighter these days however I spend for the long term and like to purchase the best I can afford. What would you do, repair the Starrett or purchase a new indicator, and why and what indicator do you recommend?

Thanks for your responses in advance.
Steve

tyrone shewlaces
11-14-2011, 05:54 PM
Some folks like the Last word, but most (me included) prefer the style like Interapid or Brown & Sharpe.

Long Island has a page comparing test indicators that's a very good read:
http://longislandindicator.com/p37.html

I have a couple or so Last Word sets that work fine, but over the past decade or two I think I've use one of them once or twice and I use my nice old BestTest indicator pretty much every day.

Long story short, if you were me you'd not spend any money at all on the Last Word since it may sit in the drawer forever and instead spend that money toward one you'll prefer to begin with.

If you have the money, Interapid is a fine device. For less money the BestTest indicators are very durable too but similar in configuration and everything else.

BTW, it's important you get the scale and range you actually need and don't go overboard on the resolution. I find that mine is about perfect for general machining and it's got 1/2 thou graduations on the dial and approx. +/- .030" of travel range. Only on occasion do I need and use my .0001" test indicator on the seldom-needed high-tolerance job - the movement is too sensitive to read easily and the short range is cumbersome I think. I would probably be just about as happy with a .001" test indicator but the half-thou one came to me like it is and it works nicely for me.

Toolguy
11-14-2011, 05:59 PM
I have a lot of indicators of various kinds. My favorite one for the inspection room is an Interapid. They are about $220 now. My next favorite one is a Fowler X Test, a copy of the Interapid. They are $80 in the latest Enco catalog. I have 2 of those for the shop, one I use and one if something happens to that one. They are extended range with .060 movement. Very smooth and repeatable. The marks are in .0005 increments, it has another small dial to keep track of turns.

macona
11-14-2011, 06:45 PM
Interapid, Compac, B & S, anything but a last word.

Fasttrack
11-14-2011, 06:56 PM
I own an Interapid DTI and I've used B&S BestTest DTI's quite a bit, too. They are both good but if money is tight, I suggest waiting until a B&S BestTest goes on sale or until you get a good promotion from Enco. (BestTest indicators tend to be just a shade less expensive than the Interapid and they are in the same class of instrument). Since they are small, a 15% off discount may save you more money than free shipping. With the Holdidays right around the corner, expect some promotions from Enco.


One thing to note is that the Interapid DTI's are "backwards". It's a little confusing at first because my intuition built from using other DTI's tells me that when I deflect the stylus one direction, the needle should move clockwise but the Interapid moves counterclockwise and vice-versa. Not a big deal, just an interesting tid-bit. ;)


Edit: Toolguy brings up another point. Depending on the resolution you want, you may opt for a DTI with greater range.

Punkinhead
11-14-2011, 07:12 PM
I like my B&S. Plenty of nice used DTI's on Ebay for embarrassingly cheap.

Bob Fisher
11-14-2011, 07:17 PM
.001 is OK with me, I have no problem with splitting a division to get to a half if necessary. seldom in my world do I need better. I have a Swiss .0005 in, can't recall the last time I used it. Ought to put on Ebay I guess. Bob.

Willy65
11-14-2011, 07:49 PM
I have two DTI's, Mitutoyo 513-402 with a range of 0-15-0 an a Interapid 312 B-1. I prefer the Interapid, but it's twice the cost of the Mitutoyo.

lost_cause
11-14-2011, 08:01 PM
let me say that first i'm very new to this field, and i hold no illusions about my capabilities so far. because of that, and the fact that this is currently a hobby, i can't justify the cost of most of the big-name precision accessories. for example, i bought my 4" mill vise as an import brand from enco because a kurt vise cost more than i paid for my mill/drill and all the accessories that i got with it.

when i learned the use for a test indicator i also decided to go with a cheap one figuring that it would be more than adequate for my needs. i paid $22 including shipping for a new one on ebay. i got it, and it works fine, but the quality is certainly not there. the indicator point is actually not even close to parallel with the body of the indicator. it's not bent or assembled wrong, but the piece the point screws into isn't machined true. as i said, it does work and return to zero fine, but it just doesn't give me that warm feeling. it's also a little ratchety (is that a word?) and noisy in the movement.

i kept looking for something a little better, since it is something that i will be using a lot. i ended up finding and buying a fowler x-test for $39 including shipping on ebay. it was basically second hand but never used. i didn't get a case or the two adapters that usually come with it, but the indicator was just like new. the fit and finish on the fowler was much better, and the movement is actually much smoother and quieter. sometime i need to replace my old dial calipers and get a drop indicator, and i'm going to go with fowler on them. it seems like a good compromise between price and quality.

tyrone shewlaces
11-14-2011, 09:02 PM
i'm going to go with fowler on them. it seems like a good compromise between price and quality.

I have a couple Fowler items (cheap bore measuring thing and a 3-4 mic) and seen a bunch of other Fowler stuff. Some of it isn't bad. My 3-4 mic is smooth and accurate along it's whole range. But I still just use it at home since I have a Mitutoyo set at work. Still, it's fine.

However, some other Fowler stuff I've seen is pretty awful. So what I would suggest is not to dismiss it off hand, but if you can, handle the one you're buying in person before you spend any good money on them.

Fowler is an Asian import and the items originate from several separate locations on that continent. Standard caveats apply.

I remember now one thing I often say to newcomer machinists:
On a DTI, it takes a little experience I think before you acquire the attention it takes to use the thing so you don't accident it into oblivion. The common example mistake is to absent-mindedly turn on a spindle and whip it around at 1200 rpm before it gets thrown to the concrete floor. So anyways, it might not be a bad idea to get a cheapie to fiddle with for a while before you invest in a nice one. I suggest this for two reasons. 1) Use of a DTI is used almost entirely for comparative measurement rather than quantitative measurement, so accuracy isn't all that important as long as it's action is smooth. 2) Even a good DTI is somewhat inherently fragile, so it takes a far less severe accident to dork it bad enough to cause problems.

There are limits of course and I've handled (briefly) a few DTIs which I just wouldn't try using. But like I mentioned, as long as the mechanism is smooth, you should accomplish what you want to with it.

becksmachine
11-14-2011, 10:03 PM
I finally retired the Last Word indicator that I have used for the past 20-25 years. It had survived numerous indignities in it's long life, including dis/re assembly and repair by yours truly. It had led a hard life in shops large and small, including my own and seemed to be bullet proof no matter how many times I would drop or crash it. It finally developed a hitch in it's get-along that I didn't want to fix at the time.

I had snagged a new one out of a pawn shop some time ago as a reserve, so now I have to fix the old one for reserve.

Dave

Mcgyver
11-14-2011, 11:22 PM
i kept looking for something a little better, since it is something that i will be using a lot. i ended up finding and buying a fowler

imo they're a bit of sham..... in the sense they are branding/marketing company and don't make anything. So you pay for their 'marketing'. If they're buying something made in Europe they'll make sure you know it, otherwise its the same chinese stuff you can buy no name...but with the prices quite a bit higher.

I seem to end up collecting indicators like hockey cards, got em, got em, need em, for some strange reason. Must have at least one of every kind. I don't know why this is so, but we'll save therapy for another day! Anyway, 98% of the time i grab for my large dial Verdict 10ths dial test indicator. that's my favorite. I also don't know why some don't like the Starrett, when i feel like mixing it up and using something different I've always like using them

I use a tenths indicator for everything. It's not many things that are done to a tenth, but whatever you're shooting for, more resolution makes it easier imo. I'm so used to it, i guess i don't understand the claims by some its more difficult to use

Fasttrack
11-14-2011, 11:42 PM
I use a tenths indicator for everything. It's not many things that are done to a tenth, but whatever you're shooting for, more resolution makes it easier imo. I'm so used to it, i guess i don't understand the claims by some its more difficult to use


Agreed. If you are going to buy a DTI, get one that has a resolution of 0.0001" or at least 0.0005" (BestTest has one that has a resolution of 0.00005" :eek: ). I even prefer my dial indicators to have a resolution of 0.0005 but sometimes the need for range out weighs the need for resolution/accuracy. Sure I almost never work to that precision, but if you are going to spend the money, get the most accurate DTI you can afford. I've never understood the "difficult-to-use" argument.

J Tiers
11-15-2011, 12:01 AM
I don't like the "Last Word" because every single one of them that I have EVER used, including mine, ones I have borrowed, etc, has been sticky and annoying.

I have Mitutoyo, Federal, B&S, ancient lever Starrett, ancient Lufkin, and no-name chinese, even a UK "Spot On" that almost looks like a last Word.

Every OTHER type of DTI works fine for me, but the Last Word always is a sticky, jumpy problem of a device.

BadDog
11-15-2011, 01:49 AM
I seem to end up collecting indicators like hockey cards, got em, got em, need em, for some strange reason. Must have at least one of every kind. I don't know why this is so, but we'll save therapy for another day!
<snip>
I use a tenths indicator for everything. It's not many things that are done to a tenth, but whatever you're shooting for, more resolution makes it easier imo. I'm so used to it, i guess i don't understand the claims by some its more difficult to use
I should save my time and just say "ditto". But I'll add that I have had and used just about every indicator style/brand there is. Interrapid, B&S, Starrett (both styles), Federal, Mitutoyo and even various imports (including Fowler and SPI labels). B&S is generally my hands down favorite, and I have them in 0.001, 0.0005, and 0.0001 with a full suite of tips. And I've got some with resolution down to 0.00001 (and only 0.002 range IIRC), like I'll ever use it...

I like the Interrapid large dial 0.060 range, but it's "backwards" to the way I think. For most things I like Mitutoyo as well or better than most any, but NOT for DTI. I while I like most of their products, I can't stand "Last Word", and I really don't care for the "normal" style Starrett either. All that said, my "favorite" is a Swiss made jeweled Tesa large dial. It's also a tenths indicator, and as said above, I most often find that suits me well. I go for the lower resolution, or larger range, only when I'm dealing with an attempt to "average errors" across something rough.

Dr Stan
11-15-2011, 02:03 AM
My DTI is a .0005" Brown & Sharpe that's at least 30 years old and works like its brand new. I too am not a fan of the Last Word by Starrett, but I do like the Interapid.

My recommendation is similar to others, try to find a B&S on sale or pick up a used one on FleaBay or at a pawn shop.

Asquith
11-15-2011, 04:55 AM
The discussion has been somewhat subjective, and I would like to make a few observations.

First, definition: It would be helpful to distinguish between types of Ďclockí. I donĎt know if there are accepted descriptions, but I would group them as (a) the finger or lever type and (b) the spindle type.

I mostly use the finger type, being very convenient for indicating, and occasionally use the spindle type - more for measuring than indicating. I find the finger type much more convenient and versatile for setting up, especially when access is poor, but of course the accuracy is limited. Also, the instrumentís weight and the spring force are usually less than with the spindle type, which might be important if youíre hanging the clock far out on a series of spindly arms!

Bear in mind the finger is actually measuring the rotation of the finger, and not linear displacement! The bigger the angle of the finger relative to the direction of movement of the work piece, the less the accuracy.

I mainly use a clock for checking run-out, parallelism, etc., i.e. not for actual measurement. I mostly use a 0.001" Verdict finger type, which has taken much abuse without complaint, and has no sign of any deadband. I also have a Baty (Swiss made) 0.0001" finger type, but as has already been said, itís often too sensitive and the limited range (0.008") can be a pain.

Incidentally, the Baty came with a test certificate which shows that it conforms with the relevant British and DIN standards (for Deviation, Total Deviation, Measuring Inversion and Repeatability). This is all academic, but shows it was a good 'un. The certificate includes correction factors to apply when the finger is working at different angles, equally academic for my purposes.

I donít suppose anything Iíve said here is helpful to the OPís original question, but I think for basic indicating purposes youíd be unlucky to find something that didnít do the job regardless of price, but since Steve has said that he spends for the long term and likes to purchase the best he can afford, then Swiss-made sounds favourite.

J Tiers
11-15-2011, 08:48 AM
AFAIK, what you call the "finger type" is what we refer to as a "DTI", or dial test indicator..... often used merely for relative motion detector, but obviously capable of use in actual measurement, if the angle error is taken into account.

As for Starrett, I have some Starrett "back plunger" type indicators, which I believe are based on the same spiral cam system as the "Last Word", but they have always been fine. they don't seem to have the "hangup" and 'sticky action" issues of the L-W.

Something about the Last Word lever mechanism is the issue with it... And, yes, I DO know how to put one back to the proper place on its cam..... And I know that the cam should be entirely free of any sort of lube.... it has a sapphire "nub" running on the hardened steel spiral cam.

Harvey Melvin Richards
11-15-2011, 11:12 AM
You can quite often find Best Test indicators on eBay that are made by Interapid. Because they are B&S, they will sell for a lot less than the Interapid.

This is one here: http://www.ebay.com/itm/BROWN-SHARPE-BESTEST-HORIZONTAL-DIAL-TEST-INDICATOR-/150557054543?pt=LH_DefaultDomain_0&hash=item230de6564f#ht_1074wt_1335

but it's not as great of a bargain as some I've seen.

firbikrhd1
11-15-2011, 11:40 AM
Thanks very much to all who have taken the time to respond and give their opinions, experiences and thoughts. Based on your responses I have decided against repair of the Starrett Last Word and narrowed the field of possibilities to B&S Bestest, Interapid, Compac and Tesa, in .0005" resolution. From what I gather in researching, resolution doesn't change the accuracy of the indicator, only the accuracy of the readings. In fact, according to Long Island Indicator, either the .001" resolution face or the .0005" resolution face can be installed on the Last Word indicators without affecting the accuracy of the indicator itself. I can split the divisions on a .0005" indicator in half and come even closer than .0005". For the work I generally do, on old WW II era machines, that level of precision should be fine. I'm not building gauge blocks or micrometer standards. This indicator will probably be used for aligning the vise and other work on the mill more than anything else although I'm sure other jobs will occasionally require it's use.

I'll be watching Ebay, the Enco sales to find the best of the above options.

JoeBean
11-15-2011, 12:04 PM
I have a B&S bestest, an interapid, a Compac, and some other Asian indicators. I went on a DTI ebay buying frenzy last winter for some reason. All of these indicators, save the Asian ones, were bought used on eBay. I set up some saved searches for what I was looking for and got some great deals.

For example, the Interapid I got for under $40, including shipping. The crystal was scratched but not badly. The seller, who had a low feedback rating after some slow shipping complaints, listed it for a quick sale with a low BIN. It took about a month to get here but it was worth it.

The Compac was also a great deal, but was an auction. It seems that most buyers in North America shy away from Compac (or maybe they're just not as well known). But British auctions seem to be the opposite - Compac fetches a good price over there.

I based my purchases on Long Island Indicator's recommendations. I figure that, like with cars, if the guys who tear them down and rebuild them don't like them then there's probably a reason. So far I haven't been disappointed.

As for which I prefer, I'd have to say that the Compac and B&S are smoother, but the Interapid is incredibly convenient. There's a good reason many of the imports copy it's design. I'd say I use the Intrapid 75% of the time, and the Compac or B&S when I'm really concerned about accuracy.


On a related note, towards the end of my buying frenzy last year I picked up a Haimer 3D taster. I don't know how I survived without it. While there are things it can't do that you can with the other indicators, I'd say if I was left with 1 indicating device in my shop it'd have to be the Haimer. It's that good. And when they come up you can often get it or the Haff & Schneier (sp?) on eBay for a good deal. But it took me about 6 months for one to come up. I paid about $180 shipped.

Black_Moons
11-15-2011, 12:12 PM
Eh, I use my $20 1" travel 0.001" resolution TDI by FAR the most. Its just so easy to use, No worrys about messing it up, etc.
My cheap chinese ($40 apparently now? Im sure I paid nearly 2x that a few years ago..) 0.030 travel 0.0005 indicator sits in the drawer most of the time.. I bring it out to align my vise.. Or when traming my mill.. thats about it really. And im sure Id never notice the diffrence if i used my 0.001" TDI to be honest.


Oh, Indicators are MUCH easyer to get into tight bores, and other tight spots however since they use left/right movement of the finger, and the finger can be 'prebent' sideways if needed (You just push it hard and it slides, you'd think the poor thing is gonna snap but it just bends.. You'll do it the first time you accidently crash the vise into the end of the indicators range :P)

lbhsbz
11-15-2011, 06:18 PM
I've got one from Enco and one from Shars...they're both junk. When dealing with 0.0001 resolution, you need a very smooth, free moving mechanism, which these don't have. They're worthless. I just picked up a new old stock "federal" DTI with 0.0001 resolution on ebay for $30. Stick with the good stuff for DTIs.

uncle pete
11-15-2011, 09:38 PM
Well some people seem to have really good luck with the cheaper indicators, Me? I'd swear I'd be better off using a wooden ruler. My personal logic is that if you want repetable and accurate readings to .0001. Your just going to have to bear what that costs for top rated equipment. And I'm in totall agreement about those excellent 3D tasters too. They are as good as the videos show. I also have a Mayr built Mitutoyo badged 20 millionths indicator for when I want to really do accurate testing on something I've bought. But I'd throw that away and keep that Taster anytime. The thing to remember is, Finger type indicators like the DTIs are ideally used to get to the zero mark. They aren't designed to be used for real accurate distance measureing. .030 distance on a .030 travel DTI will not be exactly .030. Long Island Indicator Repair is my go to place for information about what to buy. I've yet to find their information faulty.

Pete

oldtiffie
11-15-2011, 11:39 PM
I see a lot of "super good/accurate" indicators of the order of 0.0001" resolution here.

That is 0.0001" over the spanned length checked on a mill. It is 0.0001" run-out or Total Indicated Run-out" (TIR) on a lathe etc. The eccentricity of the part in the lathe relative to the lathe spindle is TIR/2 = 0.0001/2" = 0.00005" (yep - half a tenth).

I realise that many like to work to that order of accuracy most if not all of the time - but is it really needed or justified in terms of what the part has to do?

The minimising of job TIR is a static measurement where-as the job will possibly be eccentric (larger TIR) when the lathe is spinning. This is more so if the chuck is heavy or not perfectly balanced and/or is running at high speed. The turned surface may not have a low TIR when it is finished.

Put a glass of water on your head-stock and you may be surprised.

It is no accident that work in a cylindrical grinder runs relatively slowly and the grinding wheel which runs relatively is very accurately balanced.

I use tolerances/limits as well as class of surface finish that is justified by the job. If "ruff as guts" will do - it gets it. Same applies if a job requires very good accuracy and finish. The rest of my work falls in between.

I mostly use a surface guage to set my "run-out". All I need do is move the cross-slide half to halve the visual gap (TIR) and move the job in the lathe to reduce the other half. It is an iterative process.

I can get a TIR of 0.001">0.002" easily - very quick and no indicators needed. I use a 0.001" TIR indicator if needed as I can "halve" (0.0005")or "quarter" (0.00025") the indicator calibration if needed. This applies to the lathe and the mill. It works most times when an indicator is needed. Otherwise the "finer/better" indicators get to see the light of day (a very rare event).

If an indicator does not perform as it should, it gets a good whack with a hammer or squeezed in the bench vise and straight into the garbage bin.

Good indicators (all "Chinese" here) are cheap and readily available.

I can't get too excited about "indicators".

Loss/replacement of them is regarded as a consumable item and is all part of running the shop.

darryl
11-16-2011, 01:06 AM
Sound like you owners of LastWord have a last word. Let me guess, it's f---!

lbhsbz
11-16-2011, 03:25 AM
I see a lot of "super good/accurate" indicators of the order of 0.0001" resolution here.

That is 0.0001" over the spanned length checked on a mill. It is 0.0001" run-out or Total Indicated Run-out" (TIR) on a lathe etc. The eccentricity of the part in the lathe relative to the lathe spindle is TIR/2 = 0.0001/2" = 0.00005" (yep - half a tenth).

I realise that many like to work to that order of accuracy most if not all of the time - but is it really needed or justified in terms of what the part has to do?

The minimising of job TIR is a static measurement where-as the job will possibly be eccentric (larger TIR) when the lathe is spinning. This is more so if the chuck is heavy or not perfectly balanced and/or is running at high speed. The turned surface may not have a low TIR when it is finished.

Put a glass of water on your head-stock and you may be surprised.

It is no accident that work in a cylindrical grinder runs relatively slowly and the grinding wheel which runs relatively is very accurately balanced.

I use tolerances/limits as well as class of surface finish that is justified by the job. If "ruff as guts" will do - it gets it. Same applies if a job requires very good accuracy and finish. The rest of my work falls in between.

I mostly use a surface guage to set my "run-out". All I need do is move the cross-slide half to halve the visual gap (TIR) and move the job in the lathe to reduce the other half. It is an iterative process.

I can get a TIR of 0.001">0.002" easily - very quick and no indicators needed. I use a 0.001" TIR indicator if needed as I can "halve" (0.0005")or "quarter" (0.00025") the indicator calibration if needed. This applies to the lathe and the mill. It works most times when an indicator is needed. Otherwise the "finer/better" indicators get to see the light of day (a very rare event).

If an indicator does not perform as it should, it gets a good whack with a hammer or squeezed in the bench vise and straight into the garbage bin.

Good indicators (all "Chinese" here) are cheap and readily available.

I can't get too excited about "indicators".

Loss/replacement of them is regarded as a consumable item and is all part of running the shop.

You're on the ball. 99% of the I do is fine if it fals within .005, or even .010. I use my .0001 resolution dti when setting up my mill vise sometimes, but mor often than not I just use a framing square, as it's close enough more most jobs.
I was recently involved with aligning a lathe headstock, and for that job I brought out the pricey dti. It rarely gets used, buts it's nice to have when in the search for perfection....:or at least closeness

oldtiffie
11-16-2011, 05:12 AM
A very good, honest and practical reply lbhsbz as to "how it really is all" too often.

A framing square level is very accurate at 0.02mm/metre = 0.02mm/1,000mm = 1 : 0.000002mm is 0.0003146 degrees = 4.125 minutes of arc.

It is also very accurate as regards the 90 degree sides.

It beats machinists squares (all grades) hands down as regards checking verticality to the base (mill table?) reference that the framing square rests on. A great check for X:Y squareness too.

http://i200.photobucket.com/albums/aa294/oldtiffie/measuring/Machinist_Square1.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/measuring/Machinist_Square2.jpg

philbur
11-16-2011, 05:47 AM
The photos show that the scale value is 0.02mm/metre, it doesn't say what the precision of the square is?

Phil:)

PS: Also the calculation is a bit iffie!


A very good, honest and practical reply lbhsbz as to "how it really is all" too often.

A framing square level is very accurate at 0.02mm/metre = 0.02mm/1,000mm = 1 : 0.000002mm is 0.0003146 degrees = 4.125 minutes of arc.

It is also very accurate as regards the 90 degree sides.

It beats machinists squares (all grades) hands down as regards checking verticality to the base (mill table?) reference that the framing square rests on. A great check for X:Y squareness too.

http://i200.photobucket.com/albums/aa294/oldtiffie/measuring/Machinist_Square1.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/measuring/Machinist_Square2.jpg

willmac
11-16-2011, 05:57 AM
I think that lbhsbz was talking about a plain framing square as used by carpenters for putting up framing. Nothing wrong with that but it is a world away from the precision frame level that you are showing in the photos.

You could use either, but the level of available precision is very different. For me, setting a milling vice needs to be as good as I can get it because small errors quickly mount up when you are squaring up a block, and they get worse as you then machine features into it. The effect is cumulative.

J Tiers
11-16-2011, 08:42 AM
I realise that many like to work to that order of accuracy most if not all of the time - but is it really needed or justified in terms of what the part has to do?


That "justification" does not really apply in many cases*.....

Most folks here need to do very close work maybe 5 or 10 times per year..... the rest of the time "welder's tolerances" are more like what is heeded.

but there is such a thing as "practice"..... you know, "that which makes perfect".

if you reserve your efforts at very precise work for strictly and only those cases where you absolutely need it, guess what? You may not do so well, as you are out of practice.... or maybe never DID any "practice".

So many, myself included, do things to precise tolerances when "not justified", so that when we NEED TO, we have confidence that we CAN.

You, with 40+ years in the trade, can afford to take it easy when you can, it's old hat to you.



I can't get too excited about "indicators".

Loss/replacement of them is regarded as a consumable item and is all part of running the shop.

Not everyone can afford to regard a $300 or even $30 measuring tool as "consumable". It can be a bit different when running a big shop.... stuff is gonna happen, and tools will need replaced. But there you have "cash flow" and a 'tooling budget".


*
In my case, I DO use 0.0001" indicators, not so much in machining, but in scraping..... For instance when scraping the top guiding surface and the bottom guiding surface of a mill crosslide.... it wants to be precisely parallel, so a flat and a good indicator are "indicated" for testing. Same for ensuring that "parallels" are scraped to BE "parallel".....

moe1942
11-16-2011, 09:30 AM
I'll give that last word DTI a good home..

lazlo
11-16-2011, 03:56 PM
Interapid, Compac, B & S, anything but a last word.

+1 (or whatever we're up to) :) Fowler, SPI, Phase II, ... are all the same rebranded Chinese DTI.

The good news is that, like Punkinhead says, the Swiss DTI's are dirt cheap on Ebay. Highly recommend spending a couple of extra $$ and buy new in box. I've had mixed luck buying used metrology gear on Ebay.

I was the lucky buyer of the infamous "excellent condition" B&S DTI on PracticalMachist, that showed up with a bent dial.

Edit: also concur with Jerry's assertion that DTI's are not a wear item - LOL! If you take care of a fine DTI, it will last a lifetime.

oldtiffie
11-16-2011, 05:36 PM
Thanks JT.

Good sensible reasoned reply - as usual (mostly).

I sometimes give myselt a "practice run-through" just to keep my skill-set up either because I feel its time to or the the job in hand warrants it.

I break jobs and tools and methods/sequencing down to their basic or fundamental needs for the job in hand and if necesary work my way up from there.

It is surprising how often the "basics" will do and how often some of the "better" tools (including machines and processes) are rarely needed.

Needless to say a lot of my "stuff" (indicators etc.) are rarely needed or used - but they are there on or for the odd occassions when they are needed.

Screw threading is far too much worried about and given unrealistic tolerances. Here is a sample. Note the limits for OD and "over the wires"!!

http://i200.photobucket.com/albums/aa294/oldtiffie/Screw_threads/ThreadPal1.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Screw_threads/ThreadPal2.jpg


and pitch diameter limits - and clearances etc:
http://i200.photobucket.com/albums/aa294/oldtiffie/Black_book/Black_book_Fasten_P72-73_1.jpg

some should get aquainted with classes of finish and limits and fits:
http://i200.photobucket.com/albums/aa294/oldtiffie/Limits_and%20_Fits/Limits_and_Fits14.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Limits_and%20_Fits/Limits_and_Fits1.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Limits_and%20_Fits/Limits_and_Fits2.jpg

None - or very few - require much better than a 0.001" resolution indicator (use carefully to interpolate) and a bog-standard 0>1" micrometer.

I would be very disappointed if those who are srarting out and/or have limited budgets were to think that the standard cheap tools in these cases will not do the job.

oldtiffie
11-16-2011, 05:47 PM
The photos show that the scale value is 0.02mm/metre, it doesn't say what the precision of the square is?

Phil:)

PS: Also the calculation is a bit iffie!


Originally Posted by oldtiffie
A very good, honest and practical reply lbhsbz as to "how it really is all" too often.

A framing square level is very accurate at 0.02mm/metre = 0.02mm/1,000mm = 1 : 0.000002mm is 0.0003146 degrees = 4.125 minutes of arc.

It is also very accurate as regards the 90 degree sides.

It beats machinists squares (all grades) hands down as regards checking verticality to the base (mill table?) reference that the framing square rests on. A great check for X:Y squareness too.

http://i200.photobucket.com/albums/a...st_Square1.jpg

http://i200.photobucket.com/albums/a...st_Square2.jpg

I did side-track myself a bit there Phil, but that framing square comes up very well against my cylinder squares and my granite square on my granite surface plate as I had the same concerns as you did.

http://i200.photobucket.com/albums/aa294/oldtiffie/Surface%20plate/630SPandsq1.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Surface%20plate/Precgransqsheet1.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Surface%20plate/630Platesheet1.jpg

toolmaker76
11-16-2011, 08:31 PM
In 35 years in the trade I have used many indicators, and always favored the Brown and Sharp Bestest indicators.

I used the first one for over a decade, actually wore flat spots and had to replace the points. Then left it in the spindle of a mill (brain freeze, meant to engage the brake) and started it. I have to say it had a spectacular end (they don't make good bullets)!

I have several indicators now, got a Federal .0001" indicator if that kind of resolution ever comes up. Several others- can't seem to pass them up at a flea market. The Bestest gets used most often, and I have a back up in case anything happens to it. Part of the preference is probably that I have used them so much I am very comfortable with them.

adamc
03-07-2012, 02:53 PM
I realize this is an old thread, but it contains a lot of good info. I'd just like to add:

If you read Long Island Indicator's review of DTIs carefully, you'll see that they rate the Chinese test indicators very highly in their objective tests. They listed the Chinese models as more repeatable than Interapid, and faster acting. They panned them for accuracy and repairability, neither of which are important to me. I use DTI's as a comparative tool, not a quantitative one, so dimensional accuracy is irrelevent to me.

I was also turned off by the ethnic jokes (take out food and chicken feet). The owners of LII are of Swiss descent and seem to prefer Swiss tools. That said, while their humor may be un PC, I think their analysis is probably correct.

BY FAR, the biggest complaint I have with my $20 DT from LMS (and strangley not mentioned) is that its dovetails don't fit my Noga arms or ANY standard indicator studs. The Chinese DTs are wider. The studs my DTI came with were metric and also non-standard. In my shop, I need tools to work together so this has prooved the deciding factor against the Chinese DTIs (or at least mine). Before I bought a Fowler Xtest (which is made in China), I'd want to know about the dovetails.

Currently, I'm using Fowler branded Giordtast (Swiss) DTIs (highly rated by LII and cheap on ebay). I also have a pair of Fowler Quadratest digital DTIs whose button push zeroing and graphical scale are handy features.

Just for ergonomics, I like the slanted head of the Interapid. Had I to do it all over again, I think I would be happy with that one DTI alone.

I use my DTI to straighten my mill vise, check runout on tools and round stock, and center the mill to holes in the workpiece. (For this I use a vertical faced DTI). I also use DTIs as inspection tools attached to my surface gage as a sort of make shift comparator.

IMO, if you buy cheap tools or second hand tools as I do, you need to have a way to inspect them and determine their strengths and weakness. Most important tools for the beginning machinist are inspection tools (mics, dial and test indicators, and good squares- all of which are available on ebay cheap).

adamc

lazlo
03-07-2012, 08:44 PM
If you read Long Island Indicator's review of DTIs carefully, you'll see that they rate the Chinese test indicators very highly in their objective tests.

Really? I'm reading something completely different:

http://longislandindicator.com/p37.html


"China If you're buying indicators made in China, you're scraping the bottom of the barrel. You can't get any worse. Some years ago we were hired to evaluate these indicators for MSC (Manhattan Tool Supply) who wanted to know if they were worth importing. Apparently they didn't listen to our advise. "



BY FAR, the biggest complaint I have with my $20 DT from LMS (and strangley not mentioned) is that its dovetails don't fit my Noga arms or ANY standard indicator studs.

That is mentioned:


"Dovetails didn't fit and brand new .0001" indicators wouldn't calibrate. It turned out that dovetails didn't accept anyone else's attachments because they were oversized. Pass on these and order some Take-Out instead (but skip the chicken feet).

Arthur.Marks
03-07-2012, 10:21 PM
100% The damn dovetails don't fit. It is very annoying. Too wide to fit my Noga. No problem with the genuine articles. Yes, this has nothing to do with measurement, repeatability or comparative measurement, but it is a frustrating fact that you can't do any of those things unless you can mount the thing. :rolleyes: They could be the best indicator in the world, but if they don't adhere to the standard mounting dimensions then I wouldn't give a damn.

oldtiffie
03-07-2012, 10:39 PM
Odd that.

I have several of those indicators with the 3-position dove-tail mount - from Little Machine Shop and possibly CDCO tools (USA) as well as some
here in Australia. Every dove-tail fitted perfectly.

adamc
03-08-2012, 07:55 AM
Really? I'm reading something completely different:

http://longislandindicator.com/p37.html



Check out their colored chart below.

Adam

JoeLee
03-08-2012, 08:17 AM
I had a Starrett dial that the crystal fell out of too. I think after sevdral years the plastic shrunk.

JL.............................

J Tiers
03-08-2012, 08:38 AM
Odd that.

I have several of those indicators with the 3-position dove-tail mount - from Little Machine Shop and possibly CDCO tools (USA) as well as some
here in Australia. Every dove-tail fitted perfectly.

The problem stated seems to be that :

They fit THEMSELVES...... but they fit nobody else's attachments....

So it's fine if you only need what attachments they came with, but if you have any other holders, arms, etc, you may be out of luck, and have to buy or make an entirely separate set to keep set aside ONLY for the chinese ones.

Nobody seems to be complaining that they don't fit THEIR OWN attachments. (Although I HAVE seen that with other chinese stuff)

adamc
03-08-2012, 10:41 AM
The problem stated seems to be that :

So it's fine if you only need what attachments they came with, but if you have any other holders, arms, etc, you may be out of luck, and have to buy or make an entirely separate set to keep set aside ONLY for the chinese ones.


+1 That's exactly where I was. Details: My Little Machine Shop DTI shipped with 10mm and 4mm studs. 8mm (5/16") is really the standard.

The Noga fine adjusting head (FA1500 - an option on most Noga mag base arms) has 6, 8, and 10mm holes. I WAS able to mount my DTI to my Noga mag base arm using the 10mm stud.

The Noga centering arm (NF1015) has only 8mm or DT, neither of which fit the studs that came with my indicator. This head is also standard on Noga mag bases without the FA head option.

I also mount my test indicators to my Starrett surface gage to check parallels, vise jaws, and the like. My Starrett #57 has a 5/16" mast. You can get snugs that attach 3/8" to the 5/16" mast, but my (admittedly older) snug won't accept 10mm.

The solution is really to get an 8mm stud. I purchased one from MSC and filed its dovetail to make it fit the wider dts on my DTI. And while this solved the problem, I was never able to attach using the DTs.