# Lubing DTI



## Hukshawn (Oct 27, 2017)

I have a mitutoyo DTI that seems to be getting sticky. How can I lube it?


----------



## woodchucker (Oct 27, 2017)

you really don't lube a test indicator. Usually it's dirt or gum and needs to be cleaned. When you say DTI you  mean battery operated DIGITAL or analog Digit?  I have not seen a digital test indicator unless its mounted to a lab quality test stand.

I clean my analog test indicators in mineral spirits. If that doesn't work, I send it out.


----------



## Hukshawn (Oct 27, 2017)




----------



## Hukshawn (Oct 27, 2017)

How are you cleaning it? Just dunking it, swishing it around/moving it and letting it drain?


----------



## woodchucker (Oct 27, 2017)

I let the body go into the ms, I try to keep the dial out of it.  let it sit a while, then I drain it and stand it up after a while I blow it off with about 5-10psi.. just to get the remaining fluid to release from the parts, you could swing your arm with the probe hanging down it would do the same.
Mineral spirits has very light lubing qualities, and it degunks the mechanism. Its worth a try. Most dials are not paper, but I just did a federal 10ths last night and took the crystal (plastic ) off because I wanted to rub the lens with toothpaste to clean it up. and I think it was paper. I also wanted to see if I could get the arm off to see about straightening the shaft, it's wobbling.    BTW toothpaste on a lens will help clean it pretty well. It took most of the yellow out, and almost took the scratches out. This one may go out due to the shaft being bent, but hey I only paid $15 for it.

edit: let me add I have done quite a few other indicators, Mitituyo, federal, bestest... all get this treatment when I get them if they exhibit any indication of stickiness.


----------



## Hukshawn (Oct 27, 2017)

Thanks


----------



## EmilioG (Oct 28, 2017)

I personally would never "dunk" a precision instrument in any solvent like a donut.
Best to send them out. www.LongIslandIndicator.com
The problem could be worn bearings or dirty hairspring, and solvent dunking will not cure these broken parts.
DI/DTI's are like fine watches. Would you dunk a Rolex in acetone? If an internal part is worn or broken, best to leave it to the pros. IMHO

Mitutoyo has excellent DTI's/DI's that are not expensive., but they're considered "throw aways".  Much better to buy new when it comes to these gages. A Compac or Interapid will last a loooong time. Just don't dunk them in MS.   Check the above link. Great info!


----------



## woodchucker (Oct 28, 2017)

Usually not. Usually the problem is oils from work, dirt, the ms cleans and lubes.
Throw away? Really. NOT.


----------



## Hukshawn (Oct 28, 2017)

Mineral spirits lubes while it is wet. I used to use it in the food industry to lube food packaging products sliding along during manufacturing because it leaves absolutely no residue once dry. 
I think if anything, I'd be more likely to use alcohol then a dry silicone lubricant as neither of those products will melt, degrade, or destroy any of the materials. 
However, I'm more likely to contact the local company that repairs mitutoyo products. I have a digital mitutoyo micrometer that didn't work I sent it out to them and they were very reasonable 

This is my only DTI and I don't want to ruin it.


----------



## Hukshawn (Oct 28, 2017)

I originally posted because I was wondering if there was a simple and easy method to lube them. Or if it was something I should really even try myself


----------



## urmacher (Oct 29, 2017)

I have only repaired a couple of indicators.  I disassembled them,  cleaned with ultrasonic cleaner and clock cleaning solution, rinse and dry, then reassemble, lubricating with watch or clock oil, depending on size of bearing.  oil must be used sparingly to prevent it spreading away from the bearing.  Gear teeth are not oiled.  Oil on hairsprings may cause the coils to stick together if the devise is jarred.   It helps if you have repaired a few watches.  The skills are similar.


----------



## EmilioG (Oct 30, 2017)

https://www.amazon.com/Moebius-Mult...UTF8&qid=1509339514&sr=8-1&keywords=watch+oil

This is the oil pros use.  The reason that Mitutoyos, Starrett Last Word and others are considered throw aways is because they cost more to have repaired than to buy new, (in most cases). Mark Ratkowski does good work I hear. He's on FaceBook., MR TOOL REPAIR
For cleaning, Naptha is usually used.  Freon is great too, Trichloroflouroethane or trichloroethane, but hard to source. Mineral spirits leaves residue.
To properly clean a DI, it should be disassembled.


----------

