Hello everyone,
i have one question regarding depth of cut. I was searching all over internet to find something relevant but I am still getting confussed so i need to clarify this with local experiences guys.
I am very interested in depth of cut determination. I have a DYI cnc machine with very rigged steel frame and i use to have 1.5kw watercooled 24000RPM chinesse spindle. Last week i was experimenting with feedrates, RPMs and cutting depths. My goal was to reach a maximum cutting depth with 8 and 10mm 2 flute high quality carbide tool. I thoungt the higher the tool diameter the deeper depth of cut can be, but i was very wrong. After testing i destroyed the spindle bearings with 700 mm/min feedrate, 24000RPM and 6mm depth of cut with 10mm 2-flute tool high quality tool (with the 1.5kw spindle) cutting birch plywood. The machine frame stiffness is not the issue i am sure of it.
I am a novice using cncs, i know how to calculate feedrates etc as i found on the internet but i really dont know how to set the maximum cutting depth. I have ordered a new 2.2kw 24 000RPM Teknomotor professional spindle it should be much more rigged then the last one, with more and high quality bearings, but i really dont want to destroy it. They told me at the shop i ordered it, that its important to increase the spindle power if i want to go deeper and instead of insreacing the tool diameter i should decrease it. They told me also, that customers with 2.2kw spindles are ussualy able to cut 10-18mm plywoods in one or two passes using various tools from 3-6mm diameter. I also saw some videos on youtube with guys cutting 18mm plywoods with one pas on wooden framed cnc machines, with 18000RPM 2.2kw spindles mine is much more stiffer than that so I am just wondering what am I missing. I want to be able to cut 18mm plywood in 1-2 pass, with relevant feedrate using 2flute end-mills around 5mm diameter. Can anybody please give me an advice how to achieve this? Should i buy much more powerfull spindle, lower the tool diameter or what am I missing?
Thank you very much for your advice.