I am making forming taps for 3/4 and 1" Three and four feet long. I am
drilling and taping into lead 13 inches deep. Then I screw althread
stock into the taped hole and then set in epoxy. My question is what
type of steel shank extentions should I use.
The next question is how do I connect to the shank end of the tap.
This is what I have been doing so far and every thing has worked ok so
far but I might be just lucky.
I take for lets say a 3/4 10 forming tap, a 5/8 drill rod and bore one
end to .400 about 1.250 long. The other end of the drill rod I make
the same as the end of the standard tap. I then grind down tap shank
to .4006. I then heat up the drill rod to dull red and drive the tap
in. I cool the drill rod with a rag soaked in water. I next have
champhered drill rod tig welded up for a little extra force. Grind
flush the weld and use it.
Question #1 what should I do to the drill rod to make it stronger.
#2 does the heating of the end of the drill rod make it weaker?
#3 should I use drill rod or somthing like m2 tool steel. or 4130
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