Drill Bits

[JCochrun]

I've noticed that when I am drilling 10mm holes for bolt action pens, the hole is significantly larger than the tube. I've been drilling on the lathe but I tried my drill press but I got the same results. I thought that there was something wrong with my bit so I ordered a new one from Woodcraft but I'm having the same problem. So far, other size bits are ok. Any ideas on this?

Also, what are the best bits to use? I remember seeing an advertisement in some woodworking magazine about drill bits that were supposed to leave the size of the hole closest to the tubes. Does anyone know what bits I'm talking about?

Thanks,

Jim in California

 

[mredburn]

I dont know of the bits but it is well advised to measure the diameter of the tubes and match them with the closest drill bit. A lot of tubes are undersized from the stated diameters. I have all the fractional, letter, and number bits on hand as well as most of the metric sizes. Some members use one of the drill sets from HF that have all three (not the metric sizes) and are happy with that choice because of the price point. I prefer a better quality drill bit myself.

 

[NittanyLion]

Jim,

Bolt actions take a 3/8 bit. Look at the chart and you will see the difference between 10mm and 3/8:

http://content.penturners.org/library/general_reference/conversions.pdf

 

[PenPal]

Jim,

I buy quality bits however I still mike , measure, and place in baggies critical drills, have sets but prefer measured bits every time want a shock try before you buy and always measure before drilling, no more unpleasant surprises me.

Second Mikes remarks always reliable help from him.

Kind regards Peter.

 

[JCochrun]

Jim,

Bolt actions take a 3/8 bit. Look at the chart and you will see the difference between 10mm and 3/8:

http://content.penturners.org/library/general_reference/conversions.pdf

Steve....I am so stupid. I can't believe that I screwed that up. Thanks for pointing it out. For some strange reason, I thought it was 10mm. I just re-read the instructions and it does say 3/8.

Thanks,

Jim

 

[crokett]

glad you figured it out. I read the OP and was going to tell you 10mm is too large. I assembled 4 bolt-actions last night, and 3/8 is the correct size. You might be able to get away with filling the gap with epoxy and still using the blanks you drilled, but you have to be careful at the end of the blank. If you cut that too thin to meet the bushing you may expose epoxy.