I used a carbide burr, a lot cheaper and also from APT.

At a pinch, use a countersink.

Well knowing that a lot of model engineers don't like putting their hands in their pockets, the burr and making do with a CSK being classic examples I find it a good compromise as I don't tend to do a lot of chamfering.

It does come into its own on the CNC but you can still use the one tool to spot drill, countersink, chamfer and do Vee groves and engraving as well as being able to drill down into a pocket and then start enlarging it buy using the sides like any other milling cutter.

I've probably used it most as a robust engraving tool and secondly to chamfer. This collet rack is an example where I did the lettering and pre chamfered the edge of the holes before opting for a standard 3-flute cutter to do the holes but opted not to do that with the same tool as I had a board below, would have been OK on a through hole. The 6mm suits me as most of my work is fairly small and I can get closer to internal corners with the smaller dia.

This page shows the pink icons of what can be done with just the one tool. If you are wanting to do something like a large 8mmx 8mm chamfer then the chamfer mills would be the better bet as they are a lot more rigid as there are no flutes above the business end. CSK and Burr also tend to have smaller dia shanks so may not be as rigid for large chamfers or need more lighter passes to get to final size.

Having a cutter grinder I have modified an old 1/2" end mill for use as a chamfering tool. Yes we engineers are tight with our money !

That's another reason I use the 6mm one

But looking at the whole picture it is a lot more robust than your average engraving cutter so less likely to get broken, Two cutting edges so should last twice as long if not damaged and same two cutting edges mean it can be fed faster so machine is not running for so long all of which go some way to balancing out overall cost.

Edited By JasonB on 12/04/2023 13:12:22

I used a V shaped wood router bit. They have tungsten carbide cutting blades.Did the job

Thanks Jason, I was wondering what faux-pas I was commiting!

For small chamfers I use a ball end mill and just use a little bit of maths or CAD to calculate the offset from the edge to get a good 45 degree representation. The larger the diameter of the ball end, the closer the cut gets from an arc to a straight line.

Jim.

Edited By Jim Guthrie on 14/04/2023 08:42:13