Betcha you read Bob Terzuola’s book?
Now I’m sure some of the real machinists around here will have much more to say than I can but…
Compared to hand tapping, using a tapping head is such fun!
I have a different style-similar to a Tapmatic, but I may have tapped about a hundred holes in scrap as soon as I got it-just for fun because it was such a joy to do compared to hand tapping. I tried and tried to break a tap on purpose, but the clutch always let go before that happened. Good thing, as the 0-80 tap that I was using was a special order made in USA item and ran me 25$ each – I had visions of an expensive “ping” that never materialized.
In the sizes you mentioned, don’t discount a 4-40 thread if your design allows.
Especially on a pocket clip which can take a lot of abuse.
As Sun shadow mentioned, the spiral point taps are made for production and are really suited for your tapping head.
Although they might work, 4 flute hand taps are just that, made for hand tapping.
In your post you plan on doing “a” linerlock?
Well when choosing the tap, you don’t need super high priced tooling.
In business the most expensive part of the machining operation is time.
The high cost of the best cutting tools is justified by faster machining time and lower down time in tool change.
This is likely not a concern for you.
Even with using titanium, it is so thin, wear is not too bad. When using in composites such as g10 and carbon fiber, it is very abrasive on cutting tools. I can’t sharpen taps, so I consider them to be throwaway.
I recommend the most inexpensive Spiral point, machine taps (not hand taps), cutting (not roll), HSS, uncoated (unless coated is more common & therefore cheaper).
I also recommend buying from a machine tooling supplier rather than a hardware store. They will have a larger selection, a higher quality and sell in bulk rather than prepackaged items.
The money you save can be spent on having more than one.
If I can bet on anything, it’s that if I buy just one, I break or lose it.
Same can be said for drills.
Use a chart to pick the “correct” drill size and get a few of each.
They are so darn small; I toss those too instead of sharpening.
A word on drill size, most charts are calculated on 70% threads. You may also lookup or calculate a 50%, or 80% thread play with sizes, a looser or tighter hole may suit your needs.
(No jokes)
Steve
