On Sun, 31 Jul 2011 04:53:34 +0000, DoN. Nichols wrote:
On 2011-07-31, Ignoramus11951 wrote:
I have a 8 inch Digimatic caliper that is extremely dirty. I want to
clean it, but at the same time I do not want to ruin it (like I would
with compressed air). So, what would you say is a good way to clean it
from grime etc.

What kind of grime? The first thing that I would try is to see
whether a spritzing with WD-40 and a good rubdown would clean it up.
After that, rub off as much of the WD-40 as you can, as it gums things
up as it ages.

If you have to use a water-based solvent (say it is gummed up
water based coolant), I would suggest removing the battery or batteries,
closing up the battery compartment, and cleaning with a hot damp rag,
then drying it well and letting it sit for 24 hours (with the battery
case open again) before putting in batteries.

With the batteries out, the whole thing (except maybe LCD, see below)
can soak in warm distilled or de-ionized water (possibly with detergent
to cut grease and oil), followed by a soak and/or washing in ethanol,
followed by hair-dryer or heat gun briefly, and then a day in warm dry
place with slide near full extension and moved from time to time. Many
people use IPA instead of ethanol; eg see some of the following URL's.

http://arstechnica.com/civis/viewtopic.php?f=11&t=50856
http://www.arcaderestoration.com/index.asp?OPT=3&DATA=292&CBT=4
http://www.edaboard.com/thread99052.html ( avoid window cleaner)
http://www.zestron.com/us/electronics/products/pcb-cleaning.html

http://www.youtube.com/watch?v=neTSJg8iQGY shows ultrasonic
cleaning of a PCB in isopropanol; comments say to avoid putting
LCD displays in the ultrasonic cleaner. Actually, immersion of
an LCD assembly at all is slightly risky, even without ultrasonics,
because the "zebra connector" (the rubbery contacts between LCD
display glass and the LCD driver circuit board) can trap a film of
liquid which at room temperature can take weeks to dry out, so that
the display has segments that fail temporarily until the contacts
dry, or permanently if corrosion occurs.

--
jiw