Is it just me......

Bruce, I've got one of those drill presses except I spent 99 bucks for the 39 buck one. I've got to get close to downtown this morning so I'll go all the way and head to one place I know for sure that has what I'm after. I may even head to HF and get some other toys.....
 
Raymond, A 6-32 tap is the weakest tap that you can use(diameter to pitch ratio), In the material that you are tapping and the depth of hole a 60 to 70 percent ( No.33 and No. 35 drill respectively) thread will work just fine, the threads will still be strong enough to twist off the head of a screw before you pull out the threads. and the hole will be much,much easier to tap. Oh, and be sure to use a quality tapping fluid, like Tapmagic. One more thing, give the hole a small chamfer equal to at least the dia of the tap before beginning to tap.

In my 30 years + of designing machinery I have learned to avoid the 6-32 tap. for the exact reasons that you are having.

A 3mm metric screw is much strong that a 6-32 in that size range,

everything that you need can be purchased from MSC.

Well have fun
Jerry
 
Originally posted by Dan Gray

Ray you can use a 7/64 (.1094)Tap Drill for a 70% Thread
with the 6-32 tap

look here for the different bits you can use for any of the taps.
http://www.knivesby.com/drill-tap-chart.html
you have different classes of fits too,
a class (A) fit is a tight fit, you need a wrench or screw driver
to insert or remove the bolt or screw. a class B or C should be OK
Click to expand...

Jerry is my chart off?:confused:
 
Dan, The 7/64 at least for me is just to darn tight. I picked up a couple 33 and two 34 bits. Jerry, you are right on with what you had to say. I got the drill bits before I read what you posted but thats exactly how I felt. I most likly won't be using them for a couple weeks, just hope I don't end up lossing them or forgetting when I stashed them while I'm in Hondorus.....
 
Originally posted by J. Shorter
...A 6-32 tap is the weakest tap that you can use(diameter to pitch ratio... Jerry
Click to expand...

Hey Jerry, thanks for posting this. When I look back I believe I have broken more 6-32 taps than anything else, but now that you mention this it makes sense. I suppose there's formulae for this in Machinery's Handbook. I'll have to look it up. The 3mm advice is also pretty good too. I don't think in terms of millimeters when I am machining, and I know lots of other folks aren't either. I guess for a knife that will most likely never be dismantled, it really doesn;t matter whether the threads are metric or standard - only that they are strong. Good stuff here! I love to chat about threads and drilling! BOOYAH!
 
no problem Ray
I just thought you could get the 7/64" at
the store that you got the tap at,, you said they didn't
carry the numbered drills,,anyway,, the 33's will
tap easy and should hold fine.:) if it don't you'll be the frist to know about it :D just Kidding:D
 
Dan, Jeeze I don't know my chart sez a number 35 but I suppose that mine could have been rounded off. but that extra .0006 can make all the difference. I have another chart, I'll take a look.

Jerry

I just checked, both of my charts are from Morse cutting tools, however one is an abrievated chart and that is the one I was quoting, the other is the same as yours.
 
Jerry, when at the hardware store that I found the numbered drill bits they had a chart there. For a 6 32 it called for a number 36 bit, heck thats even smaller than the 7/64's that was given me all problems.
 
7/64"
now I see :)
I went back to the your first post to see
what you were using in the first place.. man
My memory is starting to get to me..:rolleyes:

Ray next time, say
you block head, that's what I'm using now..:)

a #36 ,,, they sell more taps that way:D
 
Dan, I believe your right about selling more taps. I really think the 6 32 is the big money maker. Don't feel bad about the lack of memory, it happens to us all....
 
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