Sloppy Bolster Fit

[Michael J. Spangler]

ok here comes another one i need to get straight before i get the dovetail down.
the holes i drill tend to come out a little over sized. i checked my drills and my pinstock and they're both dead on 1/8" but the holes come out a little over sized. this ends up giving my bolsters that shift while i try to grind them, resulting in uneven sides, then when i try to pin them down they walk around too much, and won't come out even. any ideas on what this is from? i figure its the drill press but what can i do to fix it? thanks again guys

Grasshoppa

p.s. happy 4th of july

 

[fitzo]

Drills just tend to do just that, Michael, drill the hole ever-so-slightly large. One way around that is to use a number-drill size less than 1/8" and ream it to 1/8" for an accurate hole. Other things that help are to always use cutting fluid on metal and use short, stubby screw-machine drills so they flex less.

 

[John L]

If you drill ..say..an 1/8 hole with an 1/8" bit it will always be oversized. You must drill 10-15 thous inder and ream to size.

 

[Ron Claiborne]

if you think its the drill press remove the chuck clean it take a rage and clean the inside of the chuck shaft holder . i got better results with a better chuck but this should help
bowie

 

[Michael J. Spangler]

hmmm i see. i do have a jacobs super duty ball bearing chuck on it. so hopefully that helps a little. i like the idea of the shorter drill bits. time to buy a shorter drill bit and some number size bits. thanks guys more suggestions are always welcome and appreciated. thanks again

 

[Ed Schempp]

I sharpen my bits, if the cutting edges are different lenghts the drill will cut an oversize hole. If you start your holes with a proper size centering or step bit your hole will be more perpendicular to the surface and a more accurate sized hole with less bit drift...Ed

 

[Chuck Gedraitis Knives]

Drill them both, tap one and then screw them together. The won't move while you shape them and then just open up the holes for your pin stock.

 

[Michael J. Spangler]

alright guys, now for the next question. what type of reamer??
i've looked through MSC, and i'm not sure what to get. i found that drilling a #31 hole is just enough under so the pins don't fit, so the ream is all i need now. thanks guys

 

[chisel]

Mike, i'll show you how i do it this weekend...they will be as tight as a frog's ass...or George's depending what time of day it is...

 

[Michael J. Spangler]

thanks Joe
that's a visual i really did not need first thing in the morning :barf: :barf: :barf:

 

[Michael J. Spangler]

well i figured it out. i think its the sloppy table on my drill press causing the problems. i drilled some holes today at IG's house and i had to burnish the pins to fit them in. so now its time to figure out how to solve that problem.
so really big parallels!!!
thanks again guys