Need To Cut Some Tool Steel

[jmarkwolf]

I have a boring bar bit I need to cut roughly in half, in order that it will fit down inside the ID of an aluminum tube (see pic). The tool is 1/4in on a side.

The shop "kid" at work thinks his new cold saw will do it. I'm skeptical.

I'm thinking a die grinder or similar is required.

Any advice?

 

[Billh50]

I would just use my angle grinder with a metal cutting disc.

 

[TommyD]

IF you cut it off where it will be used to remove metal try not to burn the cutter, cool it down every once in a while. Too much heat will take the hardness out of the cutter. We used a cut off wheel mounted on a pedestal grinder and dunked it in the water cup every once in a while.

 

[Kernbigo]

i use a surface grinder with a cut off wheel with a mister to keep it cool

 

[chips&more]

A thin cut-off abrasive wheel in a high speed motor. Or, you could carefully use the corner of a bench grinding wheel and notch it enouph, take it over to a bench vise and with an adjustable wrench at the other end, snap it apart (wear safety glasses!)…Dave

 

[Bob Korves]

Is the bit high speed steel? If so, it can be heated to a dull red before it loses its hardness. So you do not need to baby it too much. If you heat it to red it will go soft and you probably cannot re-harden it successfully at home.

 

[Ulma Doctor]

die grinder or angle grinder

if the kid's cold cut saw has teeth on it, it would be fun to watch the teeth get stripped off of the sawblade - it'd probably make all kinds of neat noises

 

[Tony Wells]

And so would the kid, especially if he has to buy the replacement blade. Cold saws are great, but the blades are HSS themselves, so won't do much cutting on HSS tool blank. I've seen some wonderful things cut with a cold saw (Haberle I believe it was). Very impressive. I've also seen a nitwit break a blade right in half. New Pamper time. I'm just glad I wasn't standing too close. It made me jump from 30 feet away.

 

[jmarkwolf]

Thanks for the input everybody.

It is indeed high speed steel.

We used a dremel with one of those heavy duty twist-lock fiber cutoff wheel.

Took awhile, and I did indeed pause and douse it with water many times.

Incidentally, the contour grind was a happy accident. I found the tool in my junk box. Don't know where I got it, but it's perfect for the grease gallery I need to cut. Just had to shorten it.

 

[dave_r_1]

I've got a boring bar like that [bar, with a spot at each end to put in a piece of HSS ground to an appropriate shape]. The guy at busy bee where I bought it suggested parting the HSS piece it came with [really long, like yours] by nicking 4 corners where you want it to break and then put it in a vice just at nicks and smack it with a hammer. It breaks off at the nicks and then you grind the shape in.

It worked for me™.