I found this sheet online for feeds and speeds. I had been cutting into foam at 10mm/s in estlcam. this suggested 1850mm feed rate when doing hardwood. I tried this speed with a 45 degree V cut on a piece of white ash and it didn’t look like it had any problems. I am reading the forums and don’t see anyone who has a feed rate over 20mm so I’m a little worried that I’m way off here and just got lucky or I dulled my bit really fast.(haven’t taken it out yet).
There is no way those numbers are for mm per second, most likely mm per minute. 1850 mm per second in Estlcam will be 111000 (mm per minute) to Marlin. Open your gcode and you will probably see
G1 X### Y### F111000
Your firmware will limit the feed rates to something not insane, I’m not sure what value exactly, and your job is probably running at that speed. If your feed rate were not limited and you actually attempted 111000 mm per minute, the odds of success would be zero.
I have it limited to 120mm/s XY and 30mm/s Z and it takes a while to accelerate in and out of a move.
That cut is great and one of the faster ones I have seen, so you have a great build to be able to handle that!
I wouldn’t trust it to not mess up at that speed so definitely bring it down some. That was cool to see your cuts being faster than you travel moves. A few tips to speed it up a bunch. If you select one pocket at a time and use “as selected” machining order instead of selecting the entire word it will cut them in order and severely decrease the travel moves. Another time saver is pocketing with a flat endmill first and switching out to a V-bit…when you get comfortable with tool changes.
That chart also looks a bit off, I am not sure I would put a lot of trust in it for our machines.
I found the source of the table on a forum at Carbide 3D. They tested their 1/4" and 1/8" flat and ball mills on all of the materials on the chart of their recommendations for speed and feed on their machines. I good resource for sure.
Concerning the units of the feed rates, they are per minute, not per second.
The 26th post says, “Plunge and feed are in distance/min. I believe the chart on the carbide3d site is inches per minute.”
Thus the 1,875 mm/min is 31 mm/s. Much more reasonable.
Thank you all, I have lowered down the feed rate and things are going great. Learning how each bit mills and how the depth changes things is where we are at now in our learning. I am making a “calibration” print at different speeds to see the difference in depth feeds and speeds.
It would be great if you could share your findings. I am a newbie to this stuff and I am also trying to learn about speeds and feeds. The table you shared will be helpful for me and any more information that I can get will also help.
I know is seems daunting but if you start with the recommended setting on the milling basics page and do small tests cuts on all your different materials before starting a job it really is easy to hear/see when things are okay. At first you are just guessing but if you follow the basics in something like pine you can really get a sense of “correct” in a matter of a handful of 5 minute test cuts. The way the chips look, the cut itself, the sound, and finally the accuracy.
Charts and calcs are extremely specific and detailed. A slightly worn bit changes this entirely, as does 1" extra Z height, or many many other things.
