Brazed Carbide vs. HSS Tools - What is better when you don't have an insert?

[BladesIIB]

Edit: This is an updated video and description.

I do probably 95% of my lathe turning with indexible carbide inserts. However, that other 5% of the time I need a specialty tool like a radius tool, or a grooving tool that I don't have an insert for. When it comes to grinding tools at home you have basically 2 choices, either Brazed Carbide or HSS. The blanks cost about the same, and the process for grinding them is very similar, you do need a Green Silicon Carbide or Diamond wheel for Brazed Carbide but then the process is pretty much the same. That said, when you need to grind one, which one is better? Which one can you expect to cut better? I thought I would do a little head to head comparison to see. To keep the comparison simple, I did not cut grooves or radii, I just did some OD turning. So in reality that is what I would do with an insert, but for the purpose of the video, it made it a lot easier to compare the surface finish.

I hope this helps you choose between Brazed Carbide or HSS when you need to make that specialty tool you don't have an insert for.

 

[westerner]

I have several brazed carbide tools that were old (but unused) when I bought them.
I also have several HSS tools in similar sizes and shapes.

I can sharpen the HSS tooling to cut FAR better than the carbide, and I am a noob too.
When I see HSS for sale at the local consignment shop, I look for new shapes, and old (therefore GOOD) pieces.
I have not given the used brazed carbide a second look.

Your mileage may vary.

 

[BladesIIB]

I have several brazed carbide tools that were old (but unused) when I bought them.
I also have several HSS tools in similar sizes and shapes.

I can sharpen the HSS tooling to cut FAR better than the carbide, and I am a noob too.
When I see HSS for sale at the local consignment shop, I look for new shapes, and old (therefore GOOD) pieces.
I have not given the used brazed carbide a second look.

Your mileage may vary.

Have you tried sharpening the old brazed carbide bits? Like HSS they do not come ready to use out of the box. You will need a Green Silicon Carbide or Diamond wheel to sharpen them. But bottom line if the HSS is working better for you that is great. I have always done far better with Brazed Carbide.

 

[benmychree]

Brazed carbide tools have little to offer in the way of chip control, it is not easy to grind in a chip breaker groove by hand; I was raised with brazed carbide tools in my apprenticeship, the company did have insert tools, but they did not work well for all classes of work. I use them quite infrequently these days, the only thing they have going for them is the ability to be frequently resharpened, and perhaps they stand up to interrupted cuts better than inserts,

 

[BladesIIB]

Brazed carbide tools have little to offer in the way of chip control, it is not easy to grind in a chip breaker groove by hand; I was raised with brazed carbide tools in my apprenticeship, the company did have insert tools, but they did not work well for all classes of work. I use them quite infrequently these days, the only thing they have going for them is the ability to be frequently resharpened, and perhaps they stand up to interrupted cuts better than inserts,

I use carbide inserts for a majority of my turning needs. Maybe my video was not clear on that since I chose to do regular turning for my comparison. Where I use Brazed Carbide most often is when in need to make a custom tool like a large radius tool, a grooving tool, or thread something where my threading insert won’t reach. When I need one of those special tools, I find Brazed Carbide is a better choice than HSS and I can get a better finish as described in the video. Hope that makes more sense.

 

[benmychree]

I use nearly exclusively TPG inserts. for the work that I do, except for rough interrupted cuts, for them, I use nearly all TNG inserts; I have a huge amount of TNG inserts that I bought in a lot for reasonable money, all USA mfg.

 

[Winegrower]

Mainly I use brazed carbide in the form of boring bars in a mill boring head, because it’s designed for them. Otherwise the preferred path is a insert, and if it’s unusual, like a trepanned O-ring groove, I grind an HSS blank.
Grinding carbide might open some doors, I will put that on the technology acquisition list.

 

[mikey]

No offense but it isn't surprising that the HSS you ground did not perform well because the tip geometry you used is suitable only for turning brass, not for any of the other materials you tested it on. If you had added 10-15 degrees of side and back rake to the tool, it would have easily roughed deeper and finished finer and more accurately than the brazed tool.

Inserts rule in industry and especially on CNC machines but on smaller, lighter manual lathes HSS often is a better choice if you grind them properly. More to the point, the best tool for the job is the best tool for the job. Sometimes that's an insert, sometimes it's a brazed tool and sometimes it's a HSS tool. You have to know how to use them all in a hobby shop and this is especially true on a small lathe.

 

[BladesIIB]

@mikey no offense taken, appreciate your thoughts on it and tips for grinding HSS. I guess I find Brazed Carbide less fussy on some of the angles to get a decent finish, and I can run it faster, maybe that is why I prefer it over HSS when I have to grind a tool.

 

[mikey]

Brazed carbide can be ground with rake angles, too, and that makes them far more capable than the typical flat top. While this does make them weaker, the improvements in cutting performance is worth it. Brazed carbide also can be ground much sharper than inserts so they are easier to take micro-cuts with to come in on size compared to inserts so brazed tools have their place. I use them and like them, too. But better than HSS in a hobby shop ... hmmm, I would leave that one to the individual.