DIY Carbide - round or square bar?

Dokkodo · 29 Apr 2021

Seen a few vids recently on making your own carbide tools and as i don't have any and could use a real pointy one for a couple projects, thought id give it a whirl.

So my question is, round or square bar? I have seen videos using both, and both seem available commercially, though the home made are more often square and commercially available seem to be round as often as not. I see advantages to both, square obviously sits on the tool rest better, where round would seem to be more manoeuvrable, though maybe thats not a good thing in terms of having a fixed face for support...

Thoughts? Annoyingly I already ordered and received my round bar, so will experiment with at least one tool in the round!

Phil Pascoe · 29 Apr 2021

Mine are round and it doesn't cause me any grief, but I shall try some hexagonal bar for the next ones.

marcros · 29 Apr 2021

My only one is square but I don't see a great issue with round. Hex or round may have an advantage actually.

Sachakins · 30 Apr 2021

Round has the advantage for shear scraping, easier to maintain a steady angle.
Square has the advantage of stabilty, especially doing the insides of boxes and vases etc,

I have some of both, but prefer the square bar personally.

Cooper · 30 Apr 2021

I made mine from square bar, as that was what I had. I have rather regretted it, as working on small internal surfaces the bottom of the bar fouls on the wall stopping the tip cutting. I think that wouldn't be such an issue with round. I filed quite a lot away, perhaps I need to do more but anymore tools I make I will use hex which I also have. The square sits on the rest very nicely though.

Phil Pascoe · 30 Apr 2021

I've some 14mm hex bar ordered, I shall reduce the last 30mm - 40mm quite a bit. My thinking is that square or hex should be more stable than round, and with hex the tool can be turned to the side and still be flat on the rest.
Incidentally, I've made 10mm round HSS skews that are brilliant to use.