Today I made my first long parts on my oversized machine.
I made some videos, where you also can see my machine:
Worked quite good.
I got the cheapest set of 7 endmills (3-12mm) for 11€ on ebay from an chinese trader and expected not much !
The 6mm chiniseium endmill broke after 20cm (DOC 7mm).
Then I used the 8mm endmill with 2 straight carbide flutes, which survived all parts. The cutter is still good , no damage or significant wear.
Theoretical feed rate would be around 3000 (0,06mm per teeth), but I went down to 60%.
Actually I have not really a comparison…I think I didnt reach the limit, but with my unstable workpiece clamping good enough. I just used 2 clamps and 2 small boards 130cm apart. In the middle the plywood even was partly hollow, which is not good.
I found a nice aproximation for Feed rate: Use ~0,5% up to 1% feed per tooth. With a 8mm 2 flute endmill @ 20000rpm its 20000 * 2 * 0,08 = F3200
DOC maybe same as cutter diameter. I havent done much on my machine, but this worked moreless.
Maybe try with some cheap cutters to figure out the limit.
I feel like we are always very cautious with our recommendations and occasionally someone comes in and just says, “I’ll make it faster until it breaks” and they end up doing great things.