Correct drill # for Tap #6-32

[Tony (Charleston WV)]

Thanks for the help.
Tony

[MT Woodworker]

7/64th or a Number 35

[barryvabeach]

Just a word to take it slow,  that is one of easiest sizes to snap.  It would be best if you had a jig to make sure it is exactly plumb to the work .  Without a jig,   if you have a drill press, you can hold the work to the table, then align the top of the tap wrench to a drill bit to give you a visual reference.  It only has to bend a few degrees off plumb to break a tap,  DAMHIKT.

[tablesawtom]

Just a word to take it slow,  that is one of easiest sizes to snap.  It would be best if you had a jig to make sure it is exactly plumb to the work .  Without a jig,   if you have a drill press, you can hold the work to the table, then align the top of the tap wrench to a drill bit to give you a visual reference.  It only has to bend a few degrees off plumb to break a tap,  DAMHIKT.

Be sure to chamfer the hole. if yo do not you will get a thick first thread and than causes tap breakage more than anything I know of. The tap will measure larger than the bolt so if you drill a hole in a piece of wood it will have to be larger than the tap, not the bolt.

The most common size of tap is an H3 it will give you a class 2 B fit which is what you want. One can get a H1 through H6 and that changes the actual size of the thread fro tighter to looser. H3 is what you want.

Tom

[DaveBeauchesne]

Just a word to take it slow,  that is one of easiest sizes to snap.  It would be best if you had a jig to make sure it is exactly plumb to the work .  Without a jig,   if you have a drill press, you can hold the work to the table, then align the top of the tap wrench to a drill bit to give you a visual reference.  It only has to bend a few degrees off plumb to break a tap,  DAMHIKT.

Not to try to muddy the waters, but my DORMER chart states to use a # 36 drill bit - good advice on the other posts about angles, etc. Good luck.

Dave B

[Bill_Houghton]

It was something of a revelation to me when I picked up a tap drill chart at a yard sale that, for some sizes, called out as many as three different sizes of tap drills for a given diameter/pitch, with a percentage of thread that would be cut using that tap drill.  Until then, I thought a particular thread required, absolutely, no alternatives, if you use the wrong one it will go on your permanent record as a demerit a particular size of drill bit.  But no, there's often choices to be made, with tradeoffs such as how strong the thread needs to be or how loose you want it.

Not so true for the smaller screws, though: the increments get too fine for how drill bits are sized.

For future reference, by the way, Tony, you can find tap drill charts all over the interweb, although they'll usually call out just one size. If a chart calls out a size you don't have, you can look up "drill bit size chart," and compare the number or letter drills, fractional drill bits, and (if you have these) metric drill bits, and see if there's something close by the size called out, that you can use to cheat.

[bandit571]

IF someone needs one of these, let me know..

   
The Dial-a-tap chart seems to be a bit too big..

   
But some of the others might work out..

   
One by Starrett..and..

   
Bay State had one....and...

   
By a George Gardner.....

I also have a chart for the Metric stuff...from "Regal Beloit"

I can stuff a chart into an envelope....$0.55 postage...

[barryvabeach]

This is my favorite chart,  it gives you all the info you would need - tap size for aluminum, tap size for steel, with drill sizes and decimal equivalents, as well as close fit and free fit clearance holes.   Little Machine Shop