Cutting Tool Recommendation

[HarryJ]

I am looking to replace my little Harbor Freight 7 x 10 mini lathe with a Grizzly 8 x 16 (don't have room for larger lathe). I found that HSS tools worked better than carbide on aluminum using my mini 7 x 10 lathe. Should I get HSS or carbide tools for the Grizzly 8 x 16? I will mainly work on aluminum and occasionally mild steel. I could use the existing mini lathe tools, but don't want to mess with multiple spacers to go from 5/16 to 3/8 tool height. Recommendations for brand of pre-ground HSS tools?

 

[VicHobbyGuy]

One question leads to another.. Do you have a Quick Change Tool Post (QCTP) on your 7x10? Adding one to your new lathe (or transferring the QCTP to the new lathe) would eliminate most requirements for shimming. I have a 7x14 and a 10x24 lathe - both equipped with QCTPs- and swap tools back and forth pretty often.
I use carbide insert tools a lot on my 7x14 lathe, and I like the sharper' 'for aluminum' inserts for cutting everything. I use home-ground HSS tools, too. When I got my lathe, I bought a set of 'pre-ground' HSS tools and I didn't like either the shapes or the quality very much. It's cheaper and more versatile (IMO) to buy HSS blanks and grind the shapes I want.

 

[WobblyHand]

One question leads to another.. Do you have a Quick change Tool Post on your 7x10? Adding one to your new lathe (or transferring the QCTP to the new lathe) would eliminate most requirements for shimming. I have a 7x14 and a 10x24 lathe - both equipped with QCTPs- and swap tools back and forth pretty often.
I use carbide insert tools a lot on my 7x14 lathe, and I like the sharper' 'for aluminum' inserts for cutting everything. I use home-ground HSS tools, too. When I got my lathe, I bought a set of 'pre-ground' HSS tools and I didn't like either the shapes or the quality very much. It's cheaper and more versatile (IMO) to buy HSS blanks and grind the shapes I want.

In the beginners forum there's a thread on grinding HSS tools. I learned a lot from that thread. For a while, tool forms were being shipped across the country to allow one to copy known working designs. I still have a copy made of key stock of the three basic forms.

That being said, I use TCGT inserts on 3/8" shank tooling for both my mini-lathe and my 10x22 lathe. I bought a bunch of cheap inserts and they work rather well. The GT suffix indicates a ground insert used primarily for aluminum, but they are great on steel and brass as well.

But I also use HSS when I have to shave off a small amount or need to make some special tooling. My external threading tool is an AXA-8, with a HSS blade HSS is relatively easy to grind and will save your bacon when you need something special, or that shape is not available commercially.

 

[C-Bag]

QCTP is a must have. Luckily my 9x20 came with it. I was lucky to join here as Mikey doing his series on how to grind HSS which is a must read and is a sticky. I bought an array of used HSS and old brazed carbide bit that were out of a defunct machine shop that will last me the rest of my life. All of them are name brand and US made and every conceivable configuration. All were sharp and most were not what is in books. So I’ve gotten to use them and several became my goto’s with one in particular being an unconventional grind that I love. Same with my old Atlas shaper. I love the fact I can grind or just hone them in shop and back in action better than before. I can also hone the brazed carbide bits as needed.

 

[ttabbal]

I like my HSS, but I use carbide inserts as well, they both have good uses. For a smaller machine, the polished carbide, usually marketed for aluminum, can work well for steels and some harder materials. They don't last as long, but they hold up pretty well for me and they are quite good.

I would say that the machine size difference isn't real significant for the forces we're talking about here. The performance of the tooling is going to be very similar.