Hi All. Newbie here but I have had some experience with CNC. I am having a problem with the S3 command on my cheap chinese 3018 machine that I have just built. It is running on a chinese Arduino Geekcreit® ATmega328P Nano V3 and I have updated GRBL to V1.1h. The problem is the following:- When I start the spindle with M3 S1000 in the G Code, movement is jerky in all axes. When I start the spindle with M3 S1000 outside the G Code, movement is smooth in all axes. I have (I think) throughly gone through the GRBL machine settings and have attached the file that I use to write them. I have also attached a small GRBL example where the problem rears its ugly head. Hope someone has some ideas as I am just about at wits end. Cheers GregiBoy
what drivers? wiring all correctly star grounded? home switch signal wires far way from motor power and spindle power wires? any chance of a video showing what you call smooth and what you call jerky? preferably exactly the same code of course.
Thanks David. The USB port is the usual cheap Chinese Serial-CH340 running at 115200 Baud. All communications appear fine through both Candle Version 1.1.7 (Various versions also tested fine) and Universal G-Code Sender Version 1.0.9 All wiring appears ok and is installed as per manufacturers instruction and all setting that I know about have been tested and the GRBL settings written. (All settings are in the file attached above) There are NO home or limit switches/wiring installed. I have tested another spindle and another control board and the same problem occurs. I will make/edit/post the comparative videos later today. (I am in Australia so there may be some time difference, currently 8:30am) Regards GregiBoy
I don't know whether to believe this or not!!! I have been checking everything methodically and after working it through and reading my notes, I hadn't eliminated on possibility, the smart powerboard that everything is plugged into. I eliminated this by plugging the machine directly into the power socket. NO more problems!!! Obviously the SMART??? powerboard is not up to the amperage required. I still csnnot understand why it works fine wehn the M3 S1000 comand is issued outside of program control though?? Still cannot believe it.
probably the lack of a time delay between powering the spindle (motors take a lot more power to start than to run) and the beginning of stepper motion when the program starts the spindle
