Internet Horology Club 185
Truing Calipers

This topic can be found at:
https://ihc185.infopop.cc/eve/forums/a/tpc/f/3426047761/m/1693949667

October 21, 2011, 23:14
Eric Unselt
Truing Calipers
Are all truing calipers created equal? I am to the point where I am in need of one.

Any advice? Preferences?
October 22, 2011, 02:33
William D. White
Eric,

I believe that Bergeon 5896 calipers would be a good choice. Beautifully made in Switzerland and reasonably priced. The adjustable index is a must for this kind of tool. I found one HERE.

William


October 22, 2011, 06:24
Chris Abell
Eric,
If you buy a used set examine very carefully the holes, steam clean them make sure no damage a tiny defect could mark/damage your pivots, also check for broken pivots/debris jammed and crushed in there!.. the type I use have no screw closing or index arm


www.Abellwatchmakers.com
October 22, 2011, 08:35
Eric Unselt
If there's no index arm, then what do you use as a reference to insure the balance wheel is both round and flat?

I thought that was kind of the point of calipers, for wheels that were taco-ed.
October 22, 2011, 09:17
Chris Abell
These are the ones that we used in watchmaking school, you can see where the errors when you rotate the balance there are lots of reference points to visually mark the error and point of correction, with these you can quickly remove the balance make a correction and re test. What works well for me is a very fine artist type brush to rotate the balance and will not apply stress to the balance you always have to remember to avoid pivot damage at all times, don’t want to make more problems while fixing another.




www.Abellwatchmakers.com
October 22, 2011, 09:43
Chris Abell
Here is another type it has set jewels also cap jewel and screw adjustment ,the problem with screw adjustments one day you will twist the wrong way.




www.Abellwatchmakers.com
October 22, 2011, 14:13
Eric Unselt
Gotcha. Thanks, Chris.
December 12, 2012, 09:49
Dave Turner
What application would this have? There are no pivot holes.
Vintage Antique Poising caliper for watch repair, watchmaker




Dave Turner
December 17, 2012, 09:47
Joseph Boone
I've also considered buying a nice caliper. I was considering the STAR JUNIOR Truing Caliper that otto frei sells. It looks nice and I've had several folks say its good.

But after reading Chris's comments I'm concerned now about the screw adjustment and turning it the wrong way :-/
February 15, 2014, 23:58
Ken Habeeb
Joseph, if you get in the habit of turning the screw a few times before the balance is in the calipers, you'll know the right way to turn in advance. And you can always mark that with tape. What I would be a little worried about with the type of calipers that Chris uses - all due respect - is that you might squeeze too hard by the scissors action of it, unless the calipers is properly oiled and/or pliable.
Neither is real fun to deal with in my very humble opinion. It's the loading that I dislike! First pivot easy, second? I'm sure that years of experience help greatly.

kh