Author Topic: Koch indicator  (Read 2678 times)

Offline V 45

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Koch indicator
« on: September 04, 2012, 03:11:09 PM »
 Hello all...I didn't really know what section to put this in...so here is an old Koch indicator I found in a box lot at the auction. It's pretty cool and in good shape. The hash marks are .0001". I have never seen one of these before. The patent date is from 1906 !! I'm guessing it's the predecessor to the best test and the like.   V 45

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Offline b.lindsey

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Re: Koch indicator
« Reply #1 on: September 04, 2012, 03:29:34 PM »
Interesting find !! I see there are a couple on e-bay at the moment. These old instruments are fascinating i think and really given the time, the mechanical ones really haven't changed that much. Thanks for sharing the picture.

Bill

Offline V 45

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Re: Koch indicator
« Reply #2 on: September 04, 2012, 05:42:46 PM »
I looked on the bay site and saw them after you had posted...I thought they might be a little more than that. I got a whole box of machinist tools for 3 bucs.  It was worth it just for the 3 in starret square.
Dave
Never assume the implied task has been completed !!

Offline b.lindsey

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Re: Koch indicator
« Reply #3 on: September 04, 2012, 06:25:28 PM »
Sounds like you hit the jackpot then :) !!!  Even if you don't use them, the old Starrett stuff is just fin to have around.

Bill

Offline Maryak

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Re: Koch indicator
« Reply #4 on: September 04, 2012, 11:32:48 PM »
Lucky you,

I've been searching for one similar to that for a long time. When I was an apprentice we were only allowed to use a dial indicator on bright or machined stock. For black bar we used a similar idea to the Koch. it had a ball end which  rested on the work and formed the horizontal part of a bell crank. The vertical part of the bell crank formed a point against a scale on the body and worked against a spring. The working range was about 0.050"

Best Regards
Bob
Если вы у Тетушки были яйца, она была бы Дядюшкой