electronic lead screw

[Qtron]

I'll have to try to deactivate the enable input to see if there really is no stepper current. The manual says nothing about the enable signal other than it must be activated at least 5 µsec before the direction signal or step signal. The controller is sending out a pulse stream whenever the lathe spindle is turning. The simpler approach will be to power down the driver after stopping the spindle. So far, that hasn't caused any problems shutting down either controller or driver first.

I Been TRYING very hard, too hard- long Hrs, to prog the 'piccolo', I keep getting message,
Nothing to build, after selecting the 'hammer' tool
Followed instructions precisely, except using latest release from github. Bah. Numb legs.
Maybe should go back to clough's first release.

 

[RJSakowski]

I Been TRYING very hard, too hard- long Hrs, to prog the 'piccolo', I keep getting message,
Nothing to build, after selecting the 'hammer' tool
Followed instructions precisely, except using latest release from github. Bah. Numb legs.
Maybe should go back to clough's first release.

I am running the first release, 1.0.0 and had no problems in flashing the program. I tried loading the 1.1.01 els-f280049c [active release] and the build completed and it got as far as preparing to flash. It errored out because I didn't have the Launchpad connected but it looked like it would have flashed had it been connected.

I have had a bit of a diversion in assembling a properly built enclosure but I should have that completed tomorrow and will be back to some testing.

 

[Qtron]

I am running the first release, 1.0.0 and had no problems in flashing the program. I tried loading the 1.1.01 els-f280049c [active release] and the build completed and it got as far as preparing to flash. It errored out because I didn't have the Launchpad connected but it looked like it would have flashed had it been connected.

I have had a bit of a diversion in assembling a properly built enclosure but I should have that completed tomorrow and will be back to some testing.

Thanks RJ, will give the 1.1.01 els-f280049c a go then. I am not TI's EDA compatible!!
Look FWD to ur testing then, cheers!

 

[GreatOldOne]

The answers will be in the code, but given that he hasn't said, I'd guess "nothing", or maybe the LED turns on. Probably just a stub in the code for now.

Maybe a Q for greatoldone! But sounds like you're on the road, makes me question the need for a servo. At 36 '' per minute carriage travel, thats not slow!
Btw, What is the overall dia of ur leadscrew?

When I got my setup to alarm, the LED on the driver does indeed light - and the servo halts. A power cycle to the driver is required to get it to restart.

 

[RJSakowski]

When I got my setup to alarm, the LED on the driver does indeed light - and the servo halts. A power cycle to the driver is required to get it to restart.

I get the same response from my driver. No effect on the Launchpad controller.

 

[Qtron]

I get the same response from my driver. No effect on the Launchpad controller.

Hiya RJ,
Got no further at this point, been distracted.
Am hoping that Briney eye's project will be completed when he is able to, of course, because, & I may be wrong, but I think he uses limit switches, which Clough42 does not do.
I reckon thats a must have feature.
A bit more messing about but a sliding position limit switch arrangement, set to be in line with the thread's gutter would be ideal.
Overspeed sensing is another important safety feature too, after seeing Mach3 / Smoothstepper go ape, and crash our router CNC at work.

 

[RJSakowski]

Hiya RJ,
Got no further at this point, been distracted.
Am hoping that Briney eye's project will be completed when he is able to, of course, because, & I may be wrong, but I think he uses limit switches, which Clough42 does not do.
I reckon thats a must have feature.
A bit more messing about but a sliding position limit switch arrangement, set to be in line with the thread's gutter would be ideal.
Overspeed sensing is another important safety feature too, after seeing Mach3 / Smoothstepper go ape, and crash our router CNC at work.

I have a design on the back burner for an electromechanical limit switch using a solenoid activated trigger mechanism to pull the half nut lever. The objective was to enable more precise end of travel for threading of machining to a shoulder. If the enable circuit works out, it would be simpler to just disable the driver. I have a mechanical stop on my ways which could be easily modified to operate an electrical circuit. There are several issues that I see.

The first is what type of proximity switching to use. I would prefer to have position repeatability to within a thou and, in my experience, microswitches can't hold that. I added optoelectronic limit switching to my Tormach and it will hold +/- .0001" but care must be taken to avoid fouling of the optics. Hall effect switches are another possibility but the magnet would have to be protected from picking up swarf. I looked at my lathe and it appears that I might be able to mount the switch on the back side of the apron.

The second issue would be the addition of wires to the front of the lathe. Any wiring adds to the clutter and creates the potential for tangling with turnings. I think I would be able to route the wires through flexible SS conduit towards the tailstock. I already have my DRO wiring routed in that direction and it hasn't been a hassle.

A third issue would be direction sensing. Ideally, a stop moving forward would still permit moving in reverse and vice versa. This could conceivably be done with steering circuitry, using the signal to the DIR input on the driver.

 

[whitmore]

I have a design on the back burner for an electromechanical limit switch using a solenoid activated trigger mechanism to pull the half nut lever.
... I would prefer to have position repeatability to within a thou and, in my experience, microswitches can't hold that. I added optoelectronic limit switching to my Tormach...

Optical switching with good accuracy... can a DRO be programmed for that function? Or, does this
really have to be a separate wired-in item?

There's good technology out there (LVDT comes to mind) for microinch triggered switches, if that is really necessary. The half-nut
might not be as fast to disengage as an electric clutch, or motor brake solution.

 

[RJSakowski]

Optical switching with good accuracy... can a DRO be programmed for that function? Or, does this
really have to be a separate wired-in item?

There's good technology out there (LVDT comes to mind) for microinch triggered switches, if that is really necessary. The half-nut
might not be as fast to disengage as an electric clutch, or motor brake solution.

My DRO's are not capable of outputing a signal at some preset position.

The advantage of optical switching is that I already have the design done. The mechanical part would need to be modified but the circuit board is already done. I don't believe that I would have to disengage the half nut. I could simply cut the pulses to the driver. It might coast for a few steps but it should be fairly repeatable. A full step is .00021" on my lathe.

 

[Flyinfool]

If you stop the lead screw at the gutter, how will you pick up the same lead for the next pass on the thread?