What sharp bits do I need?

Mostly Printed CNC - MPCNC Advice
1

Hi everyone,

I’m about to start building a mpcnc in the netherlands, since I’m in europe I was intending to get a Makita RT0700C router because it’s way cheaper than a dewalt of similar specs. I’m just unsure on which “sharp things” to get along with that router.

The router takes 6mm and 8mm shafts according to the specs. I was looking at the offerings from “HBM Machines” here in the Netherlands, I’m familiar with them from my other woodworking and they seem to make reasonable quality stuff at good prices.

Should I go for their “end mills” that have 4 flutes, or the “keyhole mills” with two flutes?

Do I just go for a 6mm mill (lose a lot of material/wood?), or should I look for a smaller router collet and use 3mm mills instead?

Thanks in advance!

2

Really depends what you’ll end up doing with it. For wood I use a double flute uncut for fast operations (requires post sanding). I just got a down cut double flute for a good finish but needs lower speeds.

Aluminum I have had success with 4 flutes.

I use mostly larger bits to eat lots of material but if you want detail you’ll want smaller.

My advice is to get one of each and play around.

3

Blimey…not surprised you needed to sand those jobs made with an ‘uncut’ bit :laughing: :laughing:

4

The most common ones in the shop are 1 flute 1/8" (3.18mm). These routers spin really fast (30k). So more flutes means you have to move super fast.

Also, if you think about cutting out a piece, using a wider bit means you have to turn more wood into chips. So in those operations, a smaller bit is faster. In a pocket, where you are removing a whole area, they are closer to the same, with an advantage to this wider bit, but not a huge advantage.

The thinner bit, with fewer flutes is at least where I would start.

5

Thanks for the advice, In the meantime I’ve found one or two sources that at least sell the 3mm collet in europe if I do need it in the end. I can’t imagine shipping from the US is very cost effective for just a collet.

What about the longer bits, I’ve ordered tubing for the standard 81mm working height. Does it make sense to grab a longer bit as well to get through thicker materrrial? The short bits look so short that I can’t imagine getting through 18mm plywood without 6mm shank getting in the way.

6

You want to use a short bit when you can. But have something capable of reaching through 19mm or more for cutting ply. If you’re cutting 12mm ply though, the shorter bits are better.

7

You can buy the 1/8 collet from Ryan’s shop, those he sells are from https://www.elairecorp.com/. I got one of those and am really happy with it. Collet plus shipping was around 40€.