Smoothstepper

[graffian]

If you look on youtube you will find someone from the mach forum's lathe which uses a smoothstepper. Hood I think his name is. He seems most impressed with it, I mailed him on youtube and asked about it, I gather he couldn't get decent rapids without one.
I wanted to try a cnc brain but the bloke over here who has one running tells me the only person with a properly working setup with one is Bruce and he doesn't infact use USB but something home made and much more robust. But I gather work is ongoing and the motion control is being completly rewritten from scratch.

I will probably be trying a SmoothStepper on my Matsuura. can you run
with 12000 counts per rev and a parrallel port?

[John S]

can you run
with 12000 counts per rev and a parallel port?

No and you can't with a Smooth stepper, try 1 count per rev,
They are setup for encoders but so far it only supports a single index pulse just like the PP.
Multi line hasn't been implemented yet.

I'm interested in one for threading on lathe, there is a problem with Mach using the PP, when threading if you thread is short, say less than 40mm the problem doesn't show.

Do a long thread and it gets out of pitch, the problem lies in the core of Mach which is still Art's baby. We have done many, many hours of testing even staying on the phone to Art for literally hours but the problem is still there.

The SS 'should' take care of this as it works real time, as you have said Hood has no problems but Hoods machines isn't the best one to beta test problems, he reckons he gets a good thread from a PP but seeing as he has something like a 12 HP motor driving a mechanical gearbox it's bound to remain stable when threading.

We mortals OTOH are trying to get hobby bench top lathes working with far smaller power facilities.

I'd love to keep my SS working long enough to do some serious test but for some reason it won't. The last 3 emails over 2 months to Greg have gone unanswered. There is a limit we can go, last month I lost 10 hours in testing various configurations, none of it chargeable.

.

[rasta]

hi;
sometime ago I cnc my little lathe using the smooth stepper, I added the index sensor in the back , and seem to work ok, well , the threading was done at 2000rpm.. I used a piece of 1/2 inch brass
sticking out 40 mm from the chuck , and the thread was 1.5 mm , the thread pitch was bigger like 3mm at the beginning and at the end, but in the middle was ok,(I think that I invented variable pitch threads.lol) I was using mach3 , and latter I found that in the parameters I should have ticked the exact stop.
one of these days I will fire the machine again and see how good it is (if it works) with a slower speed, but bear in mind.. that I have many years of experience with latest tech cnc lathes , and have observed that if you are screw cutting a 4mm pitch it shows 3.9 in the screen , maybe the thing want update the screen fast enough.
regards
Mariano