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BadDog
05-08-2007, 02:37 AM
I recently got very lucky and scored a rather wide selection of indicator tooling. Bore indicators from Starrett, Standard, and Federal among others. Interapid bore/groove comparator. Etalon indicate micrometers. You get the idea.

Of course, these have been sitting unused in an old storage room for many years. I’ve got a Mahr bench micrometer that looks like brand new, must be from the 50s I would guess.

As you may guess, some are a bit sticky and sometimes will not go back to “zero” position consistently. Some move, and stay where you leave them unless you help them back. I’ve got little into them, so not much to loose (only a few are really trouble, the rest work fine) by cleaning them myself. I really think it’s nothing but “varnish” type oil buildup from setting some 10 years or more.

Question is, do I need to buy Starrett indicator oil or the like? I was told it’s the same as “10W NonDet machine oil”. Will “Light spindle oil” do? I’ve got ISO 24(? Not sure) light spindle oil used for my Bridgeport, same stuff used for my DoAll sensitive drill spindle at 20k. I’ve got some stuff for small high rpm motor bearings, just labeled “light machine oil” with some reference to “high rpms” (not home where I can look at it). Will that do? Or should I add the (roughly) 30th bottle of special oils to my expanding collection?

The guy who recommended just using my “Light Machine oil” works at a shop that rebuilds these. If he’s wrong, don’t worry, he’s a sales guy and their shop calibration/cleaning work is well regarded. If my first foray goes poorly, I’ll probably have them do the highest dollar items (only $25-$35 each he says), but I really think it should be doable. Again, on his suggestion, just cleaning well with alcohol, then the tiniest drop of oil possible on the plunger, then transfer with pin to other tiny joints. No excess allowed, and wipe the extended plunger with lint free cloth when done. Does that sound right?

darryl
05-08-2007, 03:06 AM
I think you'll be fine using that light machine oil. Of course clean out the old gunk first, using whatever you have that's made for that. WD will work, alcohol, solvents, etc. One thing I've been caught at is when I don't get all the old gunk out first. I can free up a bearing, etc with WD, then lube, but sometimes remnants of the old oil will gum it up again.

abn
05-08-2007, 03:09 AM
I just use hypoallergenic baby oil (white mineral oil + fragrance) hypoallergenic to reduce the fragrance as much as possible. I've yet to find unscented. I don't use the consumable (laxative) type as it has vitamin-a added and can leave a residue. Idea is as much open to criticism as it is a suggestion...

miker
05-08-2007, 05:17 AM
I just got through cleaning 10 old but good condition micrometers that I picked up cheap with a lot of other stuff.
Dissassembled them and sprayed liberally with a carburetor cleaner. Meant for removing old varnish type build up in jets and passages. Really got the gunk out. Then drowned them in good old WD 40. They now spin like new. I will put a more suitable light oil in soon.

I know you are more concerned with the Dial gauges but the Carby cleaner might be worth a thought. Do not get it on Paint. Makes it go soft.

Rgds

Mac1
05-08-2007, 10:20 AM
Kerosene, to clean and lube.

pcarpenter
05-08-2007, 10:25 AM
Of course Starrett sells instrument oil that's maybe $4/bottle from Enco so you may want to go that route.

I know I keep harping on synthetics, but I tend to think that instruments are another good case for them. Dinosaur oil tends to want to return to being the tar it came from over time. Its not that synthetics are perfect, but they may tend to become less sticky. I have an indicator that has just a bit of drag from something sticky that got around the stem....its really annoying.

I too have gotten *several* dial indicators that needed work (mostly Federal) and had good luck with cleaning them up. On the indicators I have worked on, I first used a bit of alcohol or mineral spirits from the inside to wash out the old stuff from around the stem. Run it around the stem and then let it drip out the bottom. After its dry, I use some clear synthetic light lubricant with PTFE that I picked up in the checkout line at Harbor Freight. No its not some chinese crap....I can picture the label and its a name brand, I just can't recall it right now.

Paul

TGTool
05-08-2007, 10:45 AM
My experience with using the lubricant containing PTFE was not good. After lubrication the spindle felt like it was turning on cubical bearings, a real bumpy, notchy feel. Cleaning that out again and using plain oil brought it back to the silky swiss feel.

Jan

Scishopguy
05-08-2007, 11:40 AM
Several have mentioned WD-40. We all use the stuff, I do for a lot of things, but there are some things that it is not well suited for. Locksmiths absolutely hate the stuff. It lubricates but leaves a "protectant film" that attracts and retains dust and dirt. I would think twice about using that on indicators or mics. There are other options. LPS I, CRC 556, and Starrett oil all work pretty good and do not appear to gunk up stuff. By the way, 3-in-one oil is the gunkiest. A friend who was a sewing machine repair man said that he got a lot of work from folks who used 3-in-one on their machines. ;)

Swarf&Sparks
05-08-2007, 12:33 PM
FWIW, an old mate of mine swore by powdered graphite, in small doses. He was an instrument maker/fitter, so well acquainted with fine mechanisms.

Forrest Addy
05-08-2007, 01:17 PM
Once more, WD40 is NOT a lubricant. It drys to leave a film a bit like a slug trail. Neither is it a corrosion preventative. WD40 is a water dispersant and it's designed to separate water from articles that shouldn't be wet. When WD40 is used to disperse water it's an excellent product but not a lubricant or a preservative. Those who spray it on instruments and measuring tools, beware. Flush it off before it dries (takes a few days to a week) and apply a suitable oil or preservative.

WD40 by the way is an excellent cleaner and stoning media. If you use it for this purpose you're pursuing excellent technique. Just be sure to clean it off the parts and dry them before applying anything else.

RPease
05-08-2007, 01:31 PM
Once more, WD40 is NOT a lubricant.

Forrest........ :D .......When are you going to figure out that "some" people aren't interested in that?? Their "brother Darryl".......and their "other brother Darryl" have been using it for years as a lubricant.........Therefore.......It "MUST" be a lubricant....LOL

Sorry..........just couldn't resist.........going back to sleep mode now..........ROFLMAO

BTW........WD40 makes a pretty good laxative..........I hear..........LOL

lazlo
05-08-2007, 04:09 PM
Once more, WD40 is NOT a lubricant. It drys to leave a film a bit like a slug trail. Neither is it a corrosion preventative.

Forrest, you should make this a sticky post :)
WD-40 is essentially kerosene in an aerosol can. That's why it's so good for cutting/tapping aluminum :)

Starrett tech support told me to only use pure, clean mineral spirits to clean their indicators.
I also use the Starrett instrument oil for lubrication. It's expensive, but you only use the tiniest drop of it for an indicator.

lcb
05-08-2007, 06:11 PM
Clean with lighter fluid, don't let any get on dials....as best possible. If you feel you have to lube then use Starrett instrument oil, use the absolute minimum possible. Has worked well for me for over 20 yrs.

Steve Steven
05-08-2007, 06:45 PM
I have just what you need. It is instrument lubricant, surplus Gov't stuff. It is a mix of two different synthetic lubes, which have a VERY stable viscosity index over a wide range of temperature. It is intended for cronometers (accurate clocks) and is widely used for all kinds of instruments, very expensive. I am not at the house now, on a trip, and can't get to it to get the NSN so I can look up the data.

Anyway, when I get back in a week or so, I will send you a bottle (its a very small bottle, (3/4"dia X 2" long) but using it as you should it will lube many instruments. I will want postage costs in return, should be minimun USPS Priority Mail, I have sent some of this out before. I only have 9 bottles, but am willing to send it out to all who want it.

Send me a PM via the board and I'll get your mailing address so I can send it when I get home. First come first served.

Steve

Shaidorsai
05-08-2007, 11:26 PM
The best known fine instrument and clock oil is no longer available. It is Sperm oil. Yes, from Sperm Whales, which explains the unobtanium aspect. In the 1960's I scored three tiny half-ounce bottles of the stuff from a jeweller that was closing shop. It is labled "Nye Clock Oil". They were more than a few decades old when I got them. Each bottle has a tiny wire dropper in the top to dispense the oil. I expect I'll have more than half of it left when I die. A couple of clockmaker friends of mine have dibs on what's left already. It is really good stuff in that it does not oxidise readilly and get gummy. I am told that no one has yet to make a better clock oil. I mention it because you might want to keep an eye out for it at sales involving old jewelry or clock / watch shops. NYE appears to have been a popular brand. I understand they also made a fine petroleum based oil for the purpose after the ban on whaling, but it just is not as good as the original.

darryl
05-09-2007, 02:04 AM
Yeah, my brother says that WD40 is good ship. Good for everything. Ain't that right, Darryl? Yeah Darryl, that's right. :)

J Tiers
05-09-2007, 08:09 AM
Yeesh....

WD40, something with PTFE, BABY oil, ???????????????

I'm surprised someone didn't mention Rislone...... :rolleyes:

Why do the newt and bat's wing stuff when you can buy good instrument oil and have no further trouble?

Besides, if you think sperm oil is hard to get, wait until Social Services finds out about baby oil....... criminal charges will be filed for possession.

micrometer50
05-09-2007, 12:25 PM
Spray can gun cleaner and dry film gun lube seem to be working OK for me.

daryl bane
05-09-2007, 02:31 PM
Hey I resent that. and my other brother does too.

John Garner
05-09-2007, 07:14 PM
Shaidorsai --

Maybe sperm oil was the best-known non-drying oil, but Nye's finest oil was porpoise jaw oil.

A reasonable substitute for either sperm oil or porpoise jaw oil is jojoba oil, which -- perhaps ironically -- is extracted from a desert plant. Commercially pure jojoba oil can be found at most drugstores and health food / organic food stores.

If you really crave old-time authenticity, an open jar of sun-ripened fish heads underneath your workbench should compensate for what the jojoba oil lacks.

Changing the subject . . . is there a story behind your nom d'CRT? In reading it, my mind hears "Chez d'Orsay".

John

SHADOW
05-09-2007, 08:45 PM
I have the books "Repair of Mechanical Dial Indicators and Calipers" by M. Yamamato. The author uses odorless paint thinner to clean, and "leaves parts clean and coated very lightly with a film of oil". He uses clock oil or Starrett Tool and Instrument Oil for lubrication.

I have serviced several types of instruments with very fine mechanisms and have used Starrett oil and Nye Lubricants #42460 oil, each serves well. More mechanisms have seized up by using too much lubrication than by too little in my experience. The toothpick type applicator is the thing to do, applying just enough to help with friction.

I certainly agree with Forrest regarding WD40. It is my friend. I feel like sending them a Christmas card every year, it keeps bringing me business. Most of my past WD40 weilding customers would be better off holding the can and "apply directly to the forehead", a move they generally make just prior to seeking professional help. It's a wonderful tool that has it's place.

BadDog
05-12-2007, 02:18 AM
Thanks for the all the great suggestions folks.

And believe me, I am well aware of the proper (and improper) use of WD40.