Originally Posted by
dextavier99
Hi, sorry if this has been covered before, but I’ve used the search and couldn’t find anything to solve my problem.
Basically, I’m a complete novice at machining, and having made the classic mistake (I now realise) of thinking if I bought a CNC machine I could quickly and effortlessly make anything my naive heart desired, I bought a Heiz S400 and started making steady, but slow, progress, using MDF as my main material, mainly to save cost. I recently bought some brass (CZ121), which I’m lead to believe has great machining properties. It seems to cut brilliantly, but I’m having no end of trouble with snapping end mills part way through the work, ruining the piece in the process, and costing me, as a hobbyist, an unaffordable small fortune!
I’m trying to cut small gears (around 12mm diameter) so in order to get the detail, I’m using 1mm carbide end mills, which I assume are adequate for the purpose. I’ve gone down to taking 0.2mm cuts at a slow feed, and around 8,000rpm on my spindle (a Kress 1050), and although the end mills last a while longer, they’re still breaking with alarming regularity. Does anyone have any advice, as although I’ve seen plenty of feed and speed calculators, I’ve either missed the point, or can’t seem to apply them to my situation. I appreciate that I could continue reducing speeds etc, but can’t really afford to keep breaking end mills until I find the idea settings.
Sorry for rambling, but my brain and wallet are now hurting and I’m desperate to get this sorted. Thanks!