Using a Reamer

Vint

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Oct 14, 2020
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Ive started to practice the art of bushing using my drill press, following the KWM system as outlined in the Timesavers chart. It’s a great chart as it outlines the required numbered reamer etc. In my case I’m using a #41 bushing which calls for a #3 reamer. Is there an easy way to determine how far up the reamer one must drill down so that I dont drill too large of a hole? How about if I’m using a #42 which requires a #3 reamer? Any help here is most appreciated.
Thanks
 

David S

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Dec 18, 2011
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Assuming no runout in your drill press, you want to ream all the way up to and including the part of the reamer that has parallel sides.

David
 

Vint

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Thanks.....this is my first attempt at bushing and after getting your message I was so involved in getting the hole properly centered I did not run the reamer all the way up. Thanks for the clarification.
 

bikerclockguy

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Jul 22, 2017
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Thanks.....this is my first attempt at bushing and after getting your message I was so involved in getting the hole properly centered I did not run the reamer all the way up. Thanks for the clarification.
Be sure to stop it as soon as it “punches through“ though!
 

Vint

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Be sure to stop it as soon as it “punches through“ though!
For sure. Getting to this point in my clock repair is incredibly exciting. At 70 and after all the noise I made in the garage after installing a few bushings in some practice clock plates, you think I was 20,lol! Thanks again for the input.
 

Elliott Wolin

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Nov 18, 2019
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The main thing is to get an interference fit of the new bushing in the new plate hole. If by accident it isn't tight enough I've read that red Loctite works well. But if it is really loose then you have a problem (wrong reamer? too much runout?). Not sure what to do in this case, I can think of a few possibilities, but if it happens ask the experts.
 

Hudson

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Ive started to practice the art of bushing using my drill press, following the KWM system as outlined in the Timesavers chart. It’s a great chart as it outlines the required numbered reamer etc. In my case I’m using a #41 bushing which calls for a #3 reamer. Is there an easy way to determine how far up the reamer one must drill down so that I dont drill too large of a hole? How about if I’m using a #42 which requires a #3 reamer? Any help here is most appreciated.
Thanks
If a drill press has much runnout/wobble and you are chucking the #3 reamer or reamer holding adapter with a standard drill press chuck...
.......watch out. A KWM bushing reamer needs to run true or else it can and will cut an oversized hole that will not hold a bushing well.
 

Vint

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Oct 14, 2020
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If a drill press has much runnout/wobble and you are chucking the #3 reamer or reamer holding adapter with a standard drill press chuck...
.......watch out. A KWM bushing reamer needs to run true or else it can and will cut an oversized hole that will not hold a bushing well.
I see your point.....no pun intended. I actually successfully bushed a movement today consisting of an escape wheel, S2,S3,T2, T3 andT4. Can’t thank everyone enough for being helpful
Horology is complicated but experiencing “ Ah Ha” moments makes all my mistakes and oversights worthwhile!
 
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