Step drills, what brand?

[mikey]

What are the Hougen rotabroaches made of? Do they need sharpening, and if so, how often and how do you sharpen them?

The standard ones are made from M2 HSS but they also come in cobalt and carbide tipped versions. They claim to cut 3 times faster and last 10 times longer than a twist drill - no idea if this is true or how they measure that.

I haven't had to sharpen mine. Since each tooth must cut equally, I would imagine it would require a jig of some kind to get the clearance angles right but it should be doable in the shop.

 

[ACHiPo]

The standard ones are made from M2 HSS but they also come in cobalt and carbide tipped versions. They claim to cut 3 times faster and last 10 times longer than a twist drill - no idea if this is true or how they measure that.

I haven't had to sharpen mine. Since each tooth must cut equally, I would imagine it would require a jig of some kind to get the clearance angles right but it should be doable in the shop.

Thanks. Makes sense. It seems like it would be a prime candidate for carbide tips, but I'm sure that would make them even more expensive.

 

[mikey]

Yup, expensive. I can justify them for general shop use but for use on the mill or lathe, I think I'd rather just bore a hole.

 

[Silverbullet]

I have several of the HF sets and the other sizes they sell . I've been using them for years , never had to sharpen one yet. Let a friend use one and he was sold. So far in the past several years the smallest one got twisted and snapped the tip. So I guess one did need sharpening but not for being dull. I've used them for all kinds of materials . But for quick drilling with a hand drill there unstoppable . Rotobroach cutters work very well for larger holes. I have a magnet drill , makes cutting holes in plate or anything drillable. So for $9.00 three step drills years of use , rating buy again if needed.