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Ron Horton
01-16-2007, 11:23 PM
Greetings everybody--
An elderly neighbor gave me a one inch micrometer, with, believe it or don't, the word "Craftsman" stamped on it-- I didn't know Sears ever sold such equipment-- Other than looking well used, all of the numbers are legible-- And it looks very much like a Starrett Mic I have--The problem is, that when opening to measure something, the spindle?? gets progressively tighter until it will not move-- It will close OK, leading me to believe dirt or gunk has gotten into the threads-- Is this something I can fix, or does it need to be sent to a shop? I know if something is bent or broken on it, I won't be able to fix it-- I would appreciate any ideas or info you have-- Best regards, Ron

I know I just had it a minute ago--

John Garner
01-17-2007, 12:01 AM
Ron --

If the spindle isn't bent, a good soaking in a mild solvent, kerosine, mineral spirits, charcoal lighter fluid, WD-40, or something like that is in order. If you can, remove the thimble from the spindle before soaking to minimize the possibility that an air bubble will keep the solvent from getting into the threads.

I'd avoid using any more-agressive solvent, such as acetone, MEK, carburetor cleaner, or brake parts cleaner. Such solvents will cut oxidized oil "gum" rapidly, but they will also attack most plastics and may take the black filling out of the engraved markings.

The US-made, Craftsman-branded micrometers I've seen were badge-engineered Scherr-Tumico models.

John

Forrest Addy
01-17-2007, 03:52 AM
Take it apart and clean it with a toothbrush and gentle solvent. Let it soak of a day or two but not a week. Some solvents contain small amounts of sulfur as an impurity and that can cause small persistant rust sites.

Re-assemble and lube as you go with a light lube oil - Starrett instrument oil or equal. Ask you neighbor if he has the little spanner that goes with it. You may need it to take up for wear or tweak in the sleeve to align the zero.

Swarf&Sparks
01-17-2007, 04:11 AM
Had to do the same with an old Moore & Wright 25MM I got at a garage sale.
Forrest is right, toothbrush, kero then fine oil.
No spanner, so I made one from a scrap of 316 plate. Drill, hacksaw and file produced a spanner in about 5 minutes. Adjusted zero and checked with guage blocks. Right on the money, throughout the range.

ljchipmaker
01-17-2007, 07:46 AM
If it has the "ring" style lock, don't move the locking ring while you have it disassembled. I got a 1-4" set of Craftsman mics with a used Atlas/Craftsman lathe I bought. I dissassembled them for cleaning and had moved the locking ring on one while trying to take it apart further, then of course read the instructions that were in the box only to find out they recommend "not moving the locking ring while disassembled". As a result that one doesn't work as smoothly as the rest.

Larry

lazlo
01-17-2007, 11:09 AM
If the spindle isn't bent, a good soaking in a mild solvent, kerosine, mineral spirits, charcoal lighter fluid, WD-40, or something like that is in order.

Starrett tech support told me clean mineral spirits. I think mineral spirits are a more refined version of Kerosene or paraffin oil. The "low odor" mineral spirits (i.e. Stoddard Solvent) are ultra-refined. The manual for my Cadillac height gage (same precision micrometer threads) recommends the same.

I wouldn't recommend using WD-40 -- it leaves a sticky film.

Scishopguy
01-17-2007, 12:30 PM
Hi Ron,

You can do it without any problem. As was said, mineral spirits and NO WD 40. Once clean you will want to check and possibly re zero against a standard or set of gage blocks.

I was once given an old Lufkin mic, much abused and left on a dusty shelf for years. Someone had pressed the spindle from the anvil and left it in two parts. I cleaned the spindle and found that it was in good shape as far as the threads were concerned. I carefully pressed the body of the spindle back into it's place in the anvil and reassembled the spindle. The shaft was not off at all and mated perfectly with the tip on the anvil. This mic cleaned up as good as new and calibrated out just fine once I adjusted zero.

CCWKen
01-17-2007, 02:46 PM
An elderly neighbor gave me a one inch micrometer, with, believe it or don't, the word "Craftsman" stamped on it-- I didn't know Sears ever sold such equipment--

Yep, at least they did. I've had one for about 20yrs now. Still have the original "bag", wrench and box too. They're a fine piece and a good alternative to the expensive brands. I bought a Craftsman dial gauge at the same time. It would still be working if I hadn't droped a couple of weeks ago. :mad:

Make sure the lock lever is fully released.

Ron Horton
01-17-2007, 02:58 PM
Greetings guys--
Thanks so much for the response-- As always, a lot of GOOD info-- However, I've never had a mic apart, and don't have the faintest idea of how to do it-- Oh, did I mention I am a close relative of Murphy?:D If it can be screwed up, I can get 'er done:eek: -- Is there a schematic or instructions available to guide a person through this? The old gentleman who gave me the mic just moved away to be closer to his family--All of your great help is greatly appreciated--
Best regards, Ron

I know I just had it a minute ago--

speedy
01-18-2007, 04:57 AM
I just did a Google and came up with this site Ron.
http://publications.npl.co.uk/npl_web/pdf/mgpg40.pdf
Pages 39-40 should give you enough info.
My memory isn`t what it used to be (was it ever?) and I find the digital camera is a useful tool when dismantling and reassembling stuff.

Swarf&Sparks
01-18-2007, 07:18 AM
The "low odor" mineral spirits
puleeeze!

It's just a higher ethanol/methanol blend, or denaturated with 1 or 2 Iso.

Damn revenooers don't want ya buyin yer licker at the hardware store!
:D

Yes, I do run a still, my partner is a perfume blender. Only way we can get 95% ethanol is with a small reflux setup. Coupla weeks on carbon and it's entirely odourless and suitable for blending.

Not "denaturated"

rkepler
01-18-2007, 10:29 AM
Yes, I do run a still, my partner is a perfume blender. Only way we can get 95% ethanol is with a small reflux setup. Coupla weeks on carbon and it's entirely odourless and suitable for blending.

You can't buy CP ethanol from a chemical supplier? We used to use it by the gallon in labs, never had touble getting it and it sure wasn't denatured [hic].

One substitute you might be able to use - "Everclear" is one brand available in the US. All it is is ethyl alcohol with what water it can suck from the air, usually comes in 190 proof which is right at your 95%. Something like that should be available, but it's going to be a lot more expensive than a lab grade alcohol, even CP.


On edit: On the original problem. Soak the micrometer in a light oil or kerosine/diesel. Just work the action a few times once ot twice a day, out to where it stops and back a few times. If the stop is from a dried oil (and it sounds as though it is) working the action will flush it out. Using a lacquer thinner or something else might damage the paint or anything plastic on the mic (some might be hidden inside).

Swarf&Sparks
01-18-2007, 10:34 AM
Yup RK, 95% is the best you get without a vacuum still. CP ethanol is available here, at a handsome price :(
Small quantity "essential oil" distillation is legal, and cheap.

Ron Horton
01-19-2007, 01:09 AM
Greetings everybody--
Again, I can not express my appreciation for the help you have provided-- Every time I enter this site, it is a learning experience--
Yes, I am very familiar with "Everclear", but it hurts me to think of using it as a cleaning solvent--
Speedy, thanks for that site info-- Man, there is a LOT of info in that-- Seems it should be required reading for all newbys like me-- Thanks again everyone-- Best regards, Ron

I know I just had it a minute ago--