drilling a drum

[soggy]

. I need a little help with an upcomming project. I want to install a 1/4 - 28 nipple in a blank drum. The instructions say " drill a hole using a # 3 drill bit". I have a drum drilling jig from TOW, so that's no problem.
What I need to know(for now anyway :grin: ) is "What is the fraction equivlant of a # 3 drill bit. I have tried various conversion sites but can't seem to find the info that I'm looking for.
Thanks in advance;
Soggy

 

[Zonie]

A #3 drill is .2130 in diameter. A 7/32 drill is .2187 in diameter.

You could consider using a 13/64 drill which is .2031 diameter but that is ten thousandths undersize. Because it is undersize, if you use it, there is a good chanch of breaking the tap off in the hole

If this was just a thread for holding a lock screw or a tang screw in place, I'd say use the 7/32 drill, but because it is for the highly stressed, very important threads for a nipple I would suggest that you try to get the #3 drill.

Another thing about the 7/32 drill. It will be too big to be used with your drill jig because the bushing should be sized for the #3 drill.

Call around to some hardware stores or just order a few drills from TOTW or MBS.
If you absolutly cannot get a #3 drill, go ahead and use the 13/64 drill and be Very careful, backing out the tap 1/2 turn to clear the teeth for every turn you go in. Also, use REAL thread cutting oil on the tap, not plain old motor oil.

 

[soggy]

Thanks Zonie; I knew someone would come through with the info. This forum is better than any enceylopedia when it comes to B/P information. :applause:
I will try and locate a #3 drill bit before I proceed. The local hardware store ain't much, even though it's a chain store affilate, the guy who looks after that part of it doesn't seem to have much intrest in what a customer wants.
Soggy

 

[Norskie]

Use a carbon steel tap. Easier to break out with a punch if you get it stuck or break it off.
You could have gotten the #3 drill through Track, they aren't too expensive. I'm getting a 5-40 tap through them cause it ain't worth my while to try to find one locally.

 

MBS has them and their site is now up and running. Here's the link MuzzleloadersBuilders Supply It's just up so still under construction, but no.3 drill is three bucks from them. Bill

 

[khwils]

I also had a problem getting numbered bits. I went to my local Menards/Lowes and asked the kid working there if they had numbered bits. He asked me what the numerical fraction of the bit is because that's how they sell them. I tried to explain that numbered bits and also Alpha bits exist - he wasn't falling for this trick. I noticed they sell taps with the correct size bit included as a kit, I found the size tap I wanted and tried to show the kid the numerical bit but he still wasn't buying my "story". Also,they had a complete drill bit set for $30 or $40 which included Alpha, numerical and fractional bits, about 110 bits in all if I remember. I will buy that the next time I need a "odd" bit. Kurt

 

[soggy]

:thumbsup: Just a follow-up to installing my new drum; Got the drum today from TOW. I was unable to locate a #3 drill bit so I went with the 13/64" , used the cutting oil as advised and everything went like clock work. (unusual for me :rotf: ) This is the first time that I have used that type of jig and found it to be a lot easier that using the "by guess and by god method."
Looks like the weather is going to be good for the weekend so I'll get a chance to try it out . Thanks for the advice to all who contributed
Soggy