Thread: Cutting HSS ?

Sometime I need to cut down some 5/16" HSS. I use an angle grinder with just a generic thin blade. It works, but a lot of heat is generated and some discolouring becomes evident. Wonder if someone has first hand experience cutting HSS or the cobalt variant using a method which keeps heat to a minimum and cuts really well?

Thanks,
Tom

I generally notch it with a cut off disc, then put it in a vice, wrap it in a rag and hit with a hammer so it snaps.

Hi Tom,

I use a Dremal with a thin disk to put a score line where I need to snap it. Grip it in the big vise jaws so the score line is just proud and then give the end of it it a hard smack with a big hammer and a piece of bar used as a punch. Use a cloth to stop the broken off piece disappearing into that place where you will never find or see it again Don't forget to wear safety glasses, you don't want to get hit in the eyes by any fragments that may bounce around !

RC beat me to it

There the only 2 ways I know of

This is where this little variable speed bench grinder mounted saw comes into its own.
Because there's no angle grinder motor nearby I can use a spray bottle of water to keep the HSS cool - mainly so's I can hold it against the mitre slide..
I even use it to rip pieces of HSS albeit slowly.

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Just keep doing what you are doing now , the colours not going to hurt , less chance of splinters than hitting it.

It's my understanding that the heat generated by grinding is nowhere near enough to affect the hardness of HSS.

I use an angle grinder too, but I'm keen to give the other method a go.

Simon

Originally Posted by simonl

It's my understanding that the heat generated by grinding is nowhere near enough to affect the hardness of HSS.

Correct, when I did my wood machining course one of the teachers mentioned that he asked the manufacturer of the HSS knife steel they used about heat from a cutoff saw and was told that it didn't matter.

You could also try making friends with somebody who has a wire edm machine
My dad used to have one before he sold his business and retired, quite a few off cuts of HSS ended up being recycled into blanks for wood turning tools! Obviously if you had to pay someone this is not really a feasible solution.

Updating my own thread. I found using my 100mm Hitachi with thin 1mm blades I can rough out HSS without much drama.
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