What should I use...Home made Tap

This will (hopefully) be a durable tap that will be used many times. I've already started. I'm using mystery metal out of my scrap box. I think it might be stress proof because it is marked "SP" on one end.

I cut the square head on the mill using my index head. I turned down the shaft and am now starting on the threads. I'll put a taper on the end then mill two flutes. I'm thinking on cutting the relief with a file. Then heat to cherry red and quench in water.

If it turns out I'll post pictures.
 
Screwed up the threading, collet wasn't tight, work turned, scrap.

I'm going to order some 1/2" W-1 drill rod. I have some 1.125" O-1 but don't feel like turning it down to 1/2".

Out.
 
I used to make taps on a j&l thread grinder ,, all good quality taps are made of high speed steel, heat treated to 70 rockwell on the c scale and drawn back to 62-64 rockwell. Good luck not as easy as you may think.
 
MattM said:
Screwed up the threading, collet wasn't tight, work turned, scrap.

I'm going to order some 1/2" W-1 drill rod. I have some 1.125" O-1 but don't feel like turning it down to 1/2".

Out.
Click to expand...

I've been a knifemaker for about 15 years, use W2 (same as W1 but a bit of Vanadium added for Grain Refinement)

W1 will want a precise heat and quench regimen, for proper hardening.
I haven't Rockwell tested any of my taps but I would assume they are around 64Rc which is perfectly doable with W1

For proper hardening you will want to heat the steel to 1475-1480F and soak for at least 5 minutes (I do 15) for proper results this is not something you can do with a torch. you need a controlled oven.
quench you will need to do brine or a Fast quench oil
if you don't have the proper oil (sub 1 second oil) brine is easy to make

Distilled water, add salt until an unboiled egg will float.


do a flash temper around 300F for about an hour.
 
Looks good to me. Be gentle starting it, once it's hard.
 
Ha, i love it!
nice work Matt!
now watch their faces when you present them with the tool, you can't make ;)
make sure you do it as soon as you take lunch, so you can watch the expressions for the whole lunch period :grin big:
ask them, is crow is good?
 
I'm sure they will bring out their micrometers and tell me the square is off a few thou. (it is).
 
You must log in or register to reply here.
Back
Top