Hoping I can get some help with spindle RPM. Purchased a G0704 conversion from Midwest Machine several years ago. The computer controlling it had a hard drive crash and since have had it repaired. I did have the Mach3 backed up and have re-installed it. I have compared some notes from documented motor tuning and other areas that I had done some "tuning" and everything appears to be back to normal. With the exception of my spindle control. It turns on in the program like it is supposed to but the spindle was running about 3 times the programmed RPM. Program called for 1000 rpm and after running a hand tach on it I discovered it was running about 3200 rpm.
I dug through the Mach manual about spindle speed control and I can't decipher and make it work.
The motor is the "stock" G0704 1 hp 110 motor with what appears to be 4300 rpm. The Spindle Pulley set up in Pulley Config was set up with Min 0 Max 1000 Ratio 3.9, a Min 0 Max 4000 Ratio 1, a Min 0 Max 8000 Ratio 1. Which doesn't "add up" to me. The drive is running through the stock gearing set up. Motor 25T, 37T driving the jack shaft, hi-low @ 42/62T driving spindle 60/70T. I have always run in hi gear with no trouble. I normally don't program higher than 2500 rpm. The spindle seems to complain at anything much faster than that with the gear set up.
I did some experimenting with the multiple Pulley Configs and each create a somewhat accurate picture depending on different RPM ranges.
I never put a hand tach on it before this so I guess I don't know where my rpm really was but I am sure it wasn't this far off.
Does anyone have an idea where I should be looking. The motor has a single magnet and a pick up on it. I haven't noted what board is in the box. I have seen that a few people have purchased these Midwest Machine conversions and I can't find them anymore so I was hoping for some experienced guidance. Thanks for any input.