We’ve been using our ShotBot Buddy CNC router nonstop for the last three years for FRC and other projects and it’s been transformative. So far we’ve been buying Onsrud 63-618 3/16" single flute bits for this.
I was wondering if anyone has a cheaper alternative? Onsruds are great but at $37 a pop they do get expensive with student (ab)use. By the way, this is mainly for aluminum with a little ABS and polycarbonate thrown in.
I’ve been importing these new aluminium specific single flutes from china for $5 a piece and have been getting the same performance as my Onsrud bits. They are still a pain to get, I haven’t found an english re-seller.
We started to sell these because our team uses them like crazy. We mainly use the 4mm because its a .156-.157 diameter tool. It allows us to do #10 tapped holes, #8 holes and #10 holes without changing a tool, which is huge for us. We’ve had great success with them.
We have found that 2 flute end mills are more cost effective than single flutes. For roughly 2/3 the price you get an endmill that will do great and last at least as long. The key is keeping your cuts clean and lubricated.
I use https://www.mcmaster.com/#3317A22 and https://www.mcmaster.com/#3317a21/=15xtn9p for my side-business. We’ll do sheet metal in a single pass, from 0.030in to 0.080in 5052 H32, at 24IPM/24kRPM (.001ipt cut load) with good results and excellent cutter life. Cutting single-pass is remarkably useful because you don’t need to worry about re-cutting, which is the single biggest killer of router bits in my experience.
In thicker material we run around 0.05-0.06inch DOC and use an air-blast and dust collector to keep chips out of the cutting channel, with the same 24krpm and 24ipm travel.
We’ve tried running faster, but the machine doesn’t seem rigid enough. It’s a torchmate small-shop machine, mostly made from 8020 with a convoluted spindle mount.