Well it's finished and it works. Well 99% finished anyway....
It'll do 275mm on each axis. Mainly cutting perspex.
Just starting to work out cutter speeds and feed rates. At the moment it's running with the Dremel flat out and a feed of 7mm/sec which is about 1.4 ft/min. I think the rpm's are too high as the chip is very small. If i increase the feed rate the Dremel starts to run out of grunt (3mm cutter). So I should either reduce the cut depth so I can increase the feed or drop the rpm.Correct??? Would welcome any thoughts on suitable feeds and speeds.
The ideal thing is to cut at the correct feedrate. It will avoid the tip edge rubbing on the material and becoming blunt. But if you're taking really shallow cut passes, you'll only be using the lowest bit of the cutter to do cutting work... so it will wear out quicker.
I usually cut around 9000 to 1200mm/min with a 2-flute 3mm endmill 8000rpm, up to 2mm depth of cut. That's also using compressed air to blow the chips out and provide some needed cooling. I'm unsure what a dremel can accommodate though. You might need to increase the RPM and also the feedrate to match.
Best thing to do is to run some tests. Cut some slots and vary FR, DOC, RPM. You might break a couple of bits in the process, but you'll learn heaps.