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View Full Version : Sticky Indicators: Anyone have a simple fix?



bborr01
07-03-2011, 12:35 PM
Gentlemen,

I have a couple of indicators that have become a little sticky, probably from moisture in my shop and infrequent use.

A Starrett last word and a cheapo 1/4 inch travel one that I use on my lathes.

Anyone have any ideas how to solve this problem easily?

Thanks,
Brian

BridgeportBill
07-03-2011, 12:47 PM
I tried to resolve the same problem with my last word I got from my grandfather. I ended up sending it to Long Island Indicators for repair.

John Stevenson
07-03-2011, 12:51 PM
Well if you have a Starrett last word there is nothing more to say.......................

bborr01
07-03-2011, 01:11 PM
Well if you have a Starrett last word there is nothing more to say.......................

Dear Sir,

I would like to inform you that my last word indicator gave me excellent service on a very regular basis from 1978 through 2006 when I retired.

I can't see giving up on it after a track record like that.

Brian

JoeFin
07-03-2011, 01:14 PM
lighter fluid

Dr Stan
07-03-2011, 01:28 PM
lighter fluid

Ditto on the lighter fluid. In really bad cases I've disassembled travel indicators so I could clean the OD of the plunger and the ID of the plunger bushing as they tend to get sticky from cutting fluid.

bborr01
07-03-2011, 01:47 PM
Joe and Stan,

I will try the lighter fluid trick.

Thanks,

Brian

John Stevenson
07-03-2011, 03:06 PM
Last Word ?

Nothing more to say ?

Forget it then, that gem was wasted :D

bborr01
07-03-2011, 03:19 PM
Last Word ?

Nothing more to say ?

Forget it then, that gem was wasted :D

Oops,

I forgot to mention that I have a Gem that looks like a copy of a last word and it has the same problem.

Lighter fluid and a match maybe?

Brian

QSIMDO
07-03-2011, 03:23 PM
Last Word ?

Nothing more to say ?

Forget it then, that gem was wasted :D


Bread crumbs next time.
;)

DFMiller
07-03-2011, 03:29 PM
John,
Too bad that was wasted. LOL
Dave

bborr01
07-03-2011, 03:29 PM
OK John. You got me.

Right over my head.

Humor is a little different where I come from.

That was good though.

Brian

bborr01
07-03-2011, 03:32 PM
Bread crumbs next time.
;)

No bread crumbs please.

Then I would have to start a thread about getting rid of mice. :rolleyes:

Brian

DFMiller
07-03-2011, 03:35 PM
Bob,
I hope you have success on doing a quick clean on them. They are so sensitive a little bit of junk gums them up. I have a local calibration lab that seems to do wonders on this kind of thing. I have bought several ebay gems and they clean and calibrate them and I am still many bucks ahead. Then trick is to find a solvent that does not leave any residue.

Please post your results.
Dave

lynnl
07-03-2011, 05:10 PM
Last Word ?

Nothing more to say ?

Forget it then, that gem was wasted :D


Well, I thought it was funny... :)

Not as funny as the Peter Sellers mouse trap story, but still funny.

Carld
07-03-2011, 05:24 PM
I don't think the lighter fluid which is naphtha will leave any residue but many oils will. The trick is to use an instrument oil or sewing machine oil or any oil that is pure and additive free.

Dr Stan
07-03-2011, 06:29 PM
I don't think the lighter fluid which is naphtha will leave any residue but many oils will. The trick is to use an instrument oil or sewing machine oil or any oil that is pure and additive free.

We'll have to agree to disagree on this. Any oil will attract dirt & dust and will eventually become gummy, both of which cause sticking indicators. The only thing I've used to lube indicators is powdered graphite.

DATo
07-03-2011, 06:44 PM
On the Last Word problem ... make sure the little lever on the side which sets the positive or negative direction of the reading is fully engaged. Push the lever as far as it will go and then try pushing a little bit more, you might feel it snap into place. I have had this "sticky" problem before and it is usually the result of not having pushed the lever as far as it would go when previously reset the indicator's travel direction. If this seems to solve the problem then the good news is that there is nothing really wrong with your indicator.

darryl
07-03-2011, 06:48 PM
I use a product called Nutrol, which is a contact cleaner. It leaves a very light oil behind once the solvents are gone, and I've never had it gum up. Not saying it won't, or that it won't pick up dust and clog sensitive mechanisms, but it does work to dissolve crud and doesn't leave the surfaces completely dry. To my mind, there should be SOME kind of barrier coating on the moving parts. I think I would wipe the residuals off until no more wetness can be found on the cleaning rag, then stop there. The thin layer of oil that would remain wouldn't be enough to attract dirt, but would help keep the parts sliding easily.

For a dry but slick surface on the parts, you might try Bostik Top Cote. The solvents evap quickly, and once gone a slick, dry film remains. You can wear it off, but you just reapply, and it doesn't build up. I've used it on metal to metal sliding mechanisms and I'm happy with it.

Orrin
07-03-2011, 10:37 PM
I've fallen heir to a drawer-full of Last Word indicators, one at a time. About half of them are sticky because they've lost their pre-load. How they got that way is anybody's guess; however, I suspect some were dropped and the others were tinkered with by folks who didn't know what they were doing.

A Last Word uses a spiral cam. A jeweled lever follows that spiral and lost motion is prevented by pre-loading the works with a hair-spring. What happens is this: Somehow, the lever jumps out of the spiral, allowing the cam to rotate one turn and causing the pre-load to be lost.

Rather than go into an elaborate description of the procedure, (something I've done dozens of times) I'll describe what to do in general terms.

1) Remove all plugs that allow access to the internals.

2) Loosen the mechanism to allow the lever to lift out of the spiral. ISTR it is the pivot screw located under the stylus "dome." (It has been a while.) Do not remove the screw, just loosen it.

3) Using a toothpick (or similar non-scratching tool) in the spiral of the cam, rotate the cam one revolution. Keep the toothpick in place to maintain the cam's position.

4) Using your thumb, push the lever back into the spiral groove and tighten the screw that you had previously loosened to free up the lever.

5) Reassemble.

6) Check the screw under the "dome" of the stylus. Make sure it is not too loose or too tight. IMHO, a drop of oil on this pivot point isn't going to hurt a darned thing. OTOH, don't put any oil inside the body of the indicator.

Sometimes, the pivot screw head will rub on the inside of the stylus "dome." It is very easy to test to see if this is the case. Remove the stylus. If that frees up the indicator, then you've found the problem. I generally open up the inside of the dome with a tiny Dremel stone.

I cuss Last Words but use them a lot. Whenever lost motion or sluggishness cannot be tolerated, I'll grab a different make of TI.

Orrin

Carld
07-03-2011, 10:55 PM
Yep, powdered graphite works. I don't mind cleaning them and lightly oiling them. I put a drop on the plunger and then wipe it with a square of TP so there is only a film of oil.

You could probably just leave the plunger dry and do just as well. Just oil the gear pivots inside lightly. It's not like it's going to last forever like a pocket watch.

PixMan
07-04-2011, 08:00 AM
<snip>....Whenever lost motion or sluggishness cannot be tolerated, I'll grab a different make of TI.



And for me, that is ALWAYS. I like Starrett tools, and have thousands of dollars worth of them. I bought one of the No.711 Last Word kits as a young man, and used it faithfully for a number of years.

My dad let me use his Interapid, and for me that was the end of owning a Last Word. During the time I owned it I once had to replace the ball swivel attachment because it just broke apart, and twice had to send it out for a repair that sounds eerily similar to what Orrin describes.

I did a lot of work using an indicator to find the center of a bore. From the time the No.711 was new, there was always a shift of .0003" to .0005" if I turned the spindle it was mounted in clockwise or counterclockwise. When I started using an Interapid, joy. It was also easier to set up, using the jointed arm to hold the indicator's stubby but integral pivot arm.

These days I also own new Interapid 312B-4, and a Starrett No.709 may be my most-often used, but the No.711 I had saved up for an bought while working so hard to raise 3 young children...is gone. I think the open bottom of the housing sucks in dirt.

If you have one, count me in the "keep it clean and use no oil" camp.

dwentz
07-04-2011, 08:06 AM
I have had good luck with a product called "Break Free CLP" It is sold in the gun cleaning department at Wal Mart so should be available just about every where.

I had a few indicators that I purchased at an auction and most of them were gummy. I took them apart and sprayed the insides down with this stuff, and they have all been working well. Even the cheap HF units that start to stick that have gotten cutting oil on them that I have on the lathe clean up and start working again with a little of this stuff.

I use a lot of this stuff in my shop. I first heard about it on a web site that was testing rust inhibiters, and it was listed as one of the best. It is sold as a gun cleaner/lubricant/protector. I have to say that I am very happy with it. It does not gum up, stuff does not stick to it much. I wipe all my tools down with it after use and I have to say that I have less rust problems with with than with the wd-40 or oil I was using.

I have no relationship with the manufacture, just sharing something I find useful.

Dale

J Tiers
07-04-2011, 10:00 AM
if you HAVE to use a "Last Word" * then the thng to do is to clean it until the lever and little helical cam and sapphire point are absolutely clean with no oil or anything else on them. Then clean again to be sure.

Make certain the "point" has not skipped a "tooth" on the "cam".

IIRC Starrett has instructions on their site on putting the "point" back in the cam correctly. The instructions above seem similar, although I don't recall the "loosen" part.

With plunger types, a cleaning and then a film of oil on the plunger works for me and has for many years.


* I have a Last Word (actually two of them, one came with other stuff), and I have used ones belonging to others, including one brand new in the box one (not mine). Without exception they ALL "stuck", so I have a particularly bad opinion of them.

The "last word" IMO is probably "**mmit" followed by a small crunching noise......... Although I recommend selling it to another deluded soul instead.