Help
Having installed a timing disc on my Seig C1 type lathe, in accordance with the instructions in the Mach3 manual, I have a problem. I calculated the slot width according to the manual, I know it's right, the wife checked it. The software returns an accurate RPM for the spindle (exactly the same as my optical tachometer) up to about 200 RPM. Beyond that, no increase in the registered speed. Any one any ideas as to what I should do?

Ian Hart

I read somewhere on the Mach forum that for Mach Turn set the spindle pulley ratio to .1 instead of 1 like on the mill.
Config/Spindle Pulleys.
I noticed the same thing when I tested the C3 board recently.
I have one slot in the disc and Mach Mill outputs up to 6300 rpm but
when I tried Mach Turn it would only output about 300 rpm spinning at the same speed.
Haven't gone down to test it on the Mill yet but it worked on the simulator.
Hoss

can you check rpm of motor indivisually? what is pulley's speed ratio?

Thanks

I have an optical tachometer that agrees with all lower speed settings.

IanH

Sounds like the computer is not processing the pulse from the spindle. Possibly a parameter that tells the computer to sample the port more often needs to be tweaked.

Or the pulse is dying when the speed increases. I doubt this is happening but it could. Do you have access to an oscilloscope? The scope would tell you if the actual
pulse generator is working at the higher speeds.

RWW

Thanks,
I've changed the spindle pulley ratio parameter from 1 to 0.1 it just moves the accurate measuring point further up the speed scale. I wondered if providing a bigger slot might be the answer but am wary of ruining the timing disc that I have made.

IanH