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Quick question for machinists

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Brooklynrider:
How much bigger should the hole be than the bolt that is supposed to fit in it?

Aesop Rock:
http://www.physics.ncsu.edu/pearl/Tap_Drill_Chart.html

Depends on so many things, just print this out and stick it to your wall.

Brooklynrider:
Sorry, I'm having a hard time understanding all that. One bolt is 5.5mm while the other is 7.8mm. How much extra do you think I should drill?
I forgot to mention, the bolt is just supposed to slide through this hole. I am not tapping the hole.

Eggit2:
You'd want to use the clearance hole size on that chart. 5.5mm is 7/32", I don't think 7.8 is anything common, but its close to 5/16". Where did you get those diameters from?

Brooklynrider:
I know that I probably sound really dumb and I'm fully aware that I have no clue about machining. This is my first time making anything from scratch. My buddy's DH bike has an adjustable shock shuttle which must have been run loose and it developed a crack. Since the bike is a bit dated and the shock shuttle is unique to the bike, it is impossible to find a replacement. I thought I'd give it a shot and try to duplicate it. I've been using some very cheap calipers and a ruler so far. After getting all the measurements, I had a friend with a 3D printer print me a test version of the shuttle. The spacing between all the holes is perfect but the holes themselves seem to be a tad bit too small. The smaller bolts are just a tad bit too small (bolts went in but needed a bit of persuasion) but the larger top hole was noticeably too small. I think you are right, the bolts are in fact 7/32" and 5/16". Assuming those are the proper measurements, should I use the free fit or close fit measurement?

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