Sorry about the delay I get this thread moving along again. Obviously a 9/32" -32 tap is not a readily available size and you need one to make this tool. Either that or your a threading genius that can single point internal threads in a 1/4" hole.
Next thing was to do the thread calculations for a 9/32-32 tap
For anyone interested here they are
Major dia 0.281"
Minor dia 0.246"
Basic height 0.019"
Tap drill (75%) 0.250"
Compound infeed (29.5*)0.023"
With the calculations finished all that's required is to turn down a piece of tool steel to the major dia (plus .001-.002) The plus is for deflection of the work during tapping.
Put a 5 to 7* lead in angle. Just like a taper tap
Then thread it per the calculations
Tool steel always threads best when you are running as close to the rated SFM as possible. Ie the thread chase is whipping around like a ferrari....but you get a nice thread.
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