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Robert Swinney
 
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Yep! Certainly a whole lot better than gumming them up with WD-40. Puke!

Bob Swinney
"Grant Erwin" wrote in message
...
Seems like a gentle blast of clean compressed air might have helped clean
those gear teeth! - GWE

Eric R Snow wrote:

On Fri, 26 Aug 2005 00:12:13 -0700, "william_b_noble"
wrote:


thanks to the good offices of one of the NG denizens, I acquired a couple
of sick trav-a-dials. both were sticky. hee is a quick summary of an
overhaul procedu
1.submerge up to dial in rubbing alcohol, move wheel occasionally, wait
a while see if it gets fixed (this will work if what is wrong is sticky
oil that was the problem with one of them)
2. remove crystal - I used an xacto knife to pry the crystal up from it's
bezel - others have suggested a suction cup
2. submerge in rubbing alcohol, wait a while and the dial will separate
from teh glue (it worked for me)
4. use diagonal cutters to gently lift the pointer off of the shaft and
remove dial. remove knob using allen wrench.
5. remove 6 flathead screws (2 under dial), open the thing up
6. clean carefully - spray brake cleaner is helpful here
7. remove all swarf from the gear teeth. do it again, you missed some,
and again, you still missed some - inspect with jeweler's loup - oops,
still miessed some, repeat again
8. to reassemble, rotate nylon gear on top of the steel wheel
counterclockwise until the hole in the gear lines up with a hole in the
gear below. put a 1 inch piece of stiff wire in the hole and put this
aside.
9. oil the 6 ball bearings with clock oil. put a little oil on the
gears. inspect again for swarf - and remove what you rind.
10 reassemble, with the stiff wire still in place - the wire goes through
a hole that is pre-drilled in the top face of the unit
11. as you put the back (bottom) half in place, carefully align the
shafts until it snaps into place
12. reinstall 6 flathead screws (assembling the under dial stuff of
course). Oops, dont' forget the brass spring pieces that go on either
side of the drive wheel to press the seal against the surface the wleel
runs on.
13 remove the stiff wire by pulling it straight out.
14. test for smoothness. if ti's rough, you missed some swarf, go back
to step 6. if it's smooth,
15 reinstall dial, use a weak glue to hold it in place, put pointer back
onto shaft, press on lightly
16. retest, if all is well, put the crystal back in place


Your method of taking apart the thing is good. I pried, gently, at the
dial face and used alcohol too. However, I then took all the gears out
and went over the teeth with a loupe' to see which teeth had stuff in
them. I did not want to open the thing up again. The anti-backlash
gears are what is being wound up that the wire holds in place during
assembly. This is very important to make sure that there is no
backlash in the measurement. I also turned the wheel before gluing on
the face again to make sure no dirt had been missed. Thanks for
posting.
Eric