"Q" size drill bit?!!!?!?!

peepsalot

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Black 03 MSP
OK, I need to drill and tap something for 1/8" NPT. I went to a plumbing supply today and got the tap. It didn't come with a matching drill bit though. I asked the guy and he said to just use a drill bit that is closest to it. Well, I got home and looked up what the proper drill bit size would be:
http://ww2.mne.ksu.edu/classes/ME300/Reference/npt tapdrill.htm

Um, OK, what the **** is "Q", and where can I get one if the plumbing supply store doesn't even carry it? Looks like it's pretty much 1/3", but I don't think any place sells that size either.
 
The Q size drill bit is from the letter size drill series containing bits from A-Z.

Q bit diameter = 0.3320" (8.433 mm). Closest fraction size drill bit is 21/64 = 0.3281" (8.334 mm).
 
I don't believe Home Depot or Sears carries letter size drill bits, only fraction and wire size. A number of online sources carry them. Look up drill bits in Google.
 
Crap. I wanted to get this done this weekend. Every time I want to do a simple project, I have to go on a wild goose chase for a single part that no one in the world carries. Why would you have a tap and not a drill bit for the tap? It defies logic. Every place carries brass fittings in NPT sizes, but it's impossible to drill and tap for them.
 
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