Getting close
That gantry looks awfully heavy. I guess we’ll see how it accelerates when you get running?
it is pretty heavy, but it’s also super ridigid I set the acceleration to 30in/s2 at the moment. Can do 1000ipm rapid
@xue_roger Rigidity is all well, and good, to a point. Past that it does not help though. You’re not planning on cutting ferrous metals on your machine, are you? It does not look like an appropriate design to me for doing that.
@Paul_Frederick what is a good acceleration for a machine this size?
@Paul_Frederick checked the default settings of CNCrouterparts, is about 10 in/s2
@xue_roger a good acceleration is as fast as you can go without tearing your machine up, or overshooting cuts. I know I was bummed out when I had to lower my acceleration. But I burned out one of my HDPE lead nuts. Changing it was not what I would call fun either. I am definitely going to make my next machine more serviceable. That was not a design goal with this one. But it should have been.
Don’t worry about the weight of the gantry too much mine weighs about 60kg and my little nema 23 steppers move it fine. Had the whole machine (maybe 200kg) moving on its wheels when I forgot to put the brakes on the castors on when boring small holes. Sorry don’t have my acceleration numbers at hand.
Any hint on how to meassure the maximum acceleration your machine is capable of? My gantry is going to be become heavier and at that point I’ll no longer longer be able to stick with the manufacturers recommendations regarding acceleration.
@Marcus_Wolschon In LinuxCNC I use stepconf and just keep turning the acceleration up, and running the machine. It becomes pretty apparent what works, and what is out of bounds. I’ve actually backed off quite a bit compared to what I’ve run the machine at. I kind of like gentle starts.
On a semi related note I’ve also learned this snippet of G Code
G64 P.001 Q.001 (set path tolerance)
Because even at low acceleration sometimes when I am feeding my machine fudges corners. But that line makes the trajectory planner actually pay attention to what it is supposed to be doing.