Cutting 1/2 dia HSS

[trlvn]

I need to shorten a HSS boring bar to go into the boring head on my mill. Otherwise, I run out of Z height.

I think I want to use a zip disc in a 4-1/2" angle grinder* but I have zero experience with such a cut. I've only used the angle grinder a handful of times and that was with grinding and scotch-brite wheels. I have used similar cutoff wheels in the Dremel, including cutting HSS a couple of times.

A quick look online shows that there are MANY zip discs out there. Some indicate that they'll work with stainless steel but I didn't see one that said anything about HSS. This is probably a one-off thing so I don't want to waste time and money trying stuff to find out it won't work. Also, I really don't like the idea of a disc exploding in front of my face.

I'd appreciate a specific product recommendation for bricks-and-mortar store that I can go visit tomorrow.

Thanks,

Craig

*Belonged to my late brother.

 

[Dan Dubeau]

Any thin (0.045-1/16") cutoff disc should do this, but I would make sure you get a reinforced one. Some are more prone to rapid disassembly than others. I pretty much only buy dewalt ones from peavey mart when they go one sale for $1 a few times a year. Been buying them for years, and have easily gone through a few hundred of them and never had one blow up on me. I think they're around $3 regular price. I've lucked into boxes of different types for same/cheaper price before, but if I manage to catch a sale I stock up on 30-40 of them and that usually gets me through to the next sale.

A face shield is always recommended PPE when using cut off discs. Use the guard on the grinder, and clamp the boring bar securely in a vise. Hold the grinder so the wheel is rotating down and throwing sparks toward the ground, and feed straight in. The guard should be positioned between you and the cut. Shouldn't take much force to zip right through. Cut off wheels are great for roughing in hss cutters, saving loads of time at the bench grinder.

 

[Arbutus]

Recommended. Cuts through hardened steels easily, with little kerf. Ignore the price sticker. Bought at Home Hardware

 

[phaxtris]

any zip disc will cut hss

the ones marketed for stainless just have no iron in the discs and will not contaminate stainless, the ones for aluminum are designed to be more frangible, and will disintegrate much faster by design, but any of them will work

sait, klingspore, 3m, all high end discs, cheap discs work as well just tend to not last as long

 

[Jswain]

As mentioned anything will work, I'd just grab the thinnest metal cutting disk at your local Canadian Tire, can probably get a 25pk(if they are on sale)for the price of 1 decent disc.

Haven't had very many blow up on me from there and if they did it was a my fault situation. Keep the guard on the grinder and wear safety glasses & a face shield. The second you don't is when one will blow up.

3/64" thick discs are what you want, 1/16" at a max anything else takes a LONG time to cut

Going to be store specific for sales/packages just this one is on sale for me with 25 of the 3/64" discs, you should be able to get them by their selves or smaller packs as well.