drill for front rail pins

[Joseph Garrett]

Terry, the Farrell, asked: "Thanks to all who offered suggestions for rebuilding the front rail of an action frame I am working on. I posted a couple days ago about and action frame with erratic front rail pins (angled every-which-way). I have epoxied in two one-inch (wide) by one-half-inch (thick) hard maple inserts that run the lengths where the front rail pins for the naturals and sharps go. A little belt sanding, etc. after an overnight cure and I will be ready to drill new holes for the front rail pins.

If the holes I drilled trough the bottom are not full of epoxy!!!!!!!!!!!!!!!!

Let's say they aren't. My question is how big a hole to drill for a nice, tight, long-lasting, non-maple-strip-splitting, fit? So that's the question: what size is tight enough to hold the pin securely, but not so tight as to split the wooden rail?

The pin bases have a diameter of 0.176 inches. Among commonly available drill bit sizes is 11/64". The decimal equivalent of 11/64" is 0.172-inches. I miced the two 11/64" drill bits I have and found they mic out to 0.170-inches. Numbers look promising to me.....

And for sure, I think it is safe to say that I can expect some run-out.

The only thing I can think of to do is test drill a few holes in a scrap of maple and choose the largest diameter hole that seems tight enough. I would hope maybe there might be some more precise information out there.

Does anyone have any good woodworking experience who could suggest an answer to my question?"

Thanks.

Terry,
TSK! TSK! <G> I think it's time for you to go to the Good Hardware Store and buy a set of NUMBER DRILLS! 
I mic'd the end of the key pins, I have in stock. The mic'd at: .174". When drilling wood, I'd advise using a #17, (.173"), if you want a fairly loose fit. The next choice is a 11/64". the next choice is a #18, (.1695"). I've found that the hole will ACTUALLY be slightly larger than the drill used. This is caused by the material "working" it's way up the flutes and out of the hole. Tends to make the top of the hole larger than the bottom. My choice would be the #18 drill.
BTW, you also need to get a STARRETT Decimal Equivalent Chart, (pocket size)! I use mine, (I have several scattered hither thither and yon, but usually with my drill sets<G>), ALL the time! Starrett gives them away...FREE! They're made out of plastic and work well for quick checking of Decimal to Drill sizes. A MUST HAVE ITEM, IMHO!
Kinda on the same subject: I'm looking for a complete set of LETTER SIZE DRILLS, in it's own caddy. I check with several companies and can't seem to find any that market them this way. All I can find is the individual drills. (Not a neat way to store them...as in a cigar box or????) Anyone know of a possible source?
Regards, 


Joe Garrett, R.P.T. (Oregon)
Captain, Tool Police
Squares R I
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