X homing

[rdean]

Hello all, hope this is in the right section.

I have been searching for any information on independently homing the X axis motors on a PRT 96 with a V4g upgrade.

I have done this on another PRT machine that was changed over to run on Mach3 but this machine is running the ShopBot software.
Any help or guidance is appreciated.

Thanks
Ray

[garyc]

Ray...
This will work for you by pressing [C][3] from the console. Or mouse to the [C]uts menu and select "C3"

1) Prox switches must be installed
2) ShopBot Setup ([T][S]) should be run to set the proper rollback distance for each switch.

The manual for the machine should explain this well. Look here: http://www.shopbottools.com/mSupport/documentation.htm

[rdean]

Thanks for the quick reply Gary but I may not have explained fully what I am looking for.

The X axis will have two proxs one each located on each main side rail of the machine. When homing the sequence should be something similar to the following.

The gantry moves in a X- direction until it encounters the prox switches and stops.
One side of the gantry moves in the X+ direction until that prox is deactivated then reverses itself back on to the switch at a reduced speed. It then moves X+ to a set distance.
After that sequence is done the other gantry motor does the same sequence as the first did.

This not only moves the gantry to the home position but also squares the gantry to the machine.

Thanks
Ray

[Brady Watson]

Ray,
The short answer is no. If you set your mechanical stops when your gantry is known to be square & you are concerned about it being squared down the road, you turn off the power to the control box, pull the gantry against the stops and power it up. It is then square. It is not normal for a good running tool to go out of square unless you crash it.

Since you may be running an older PRT, I would advise you to get it square and lay a weld bead on the 4 corners to make sure it stays that way. That's what I did on mine & have never regretted it. (This is for the 100% steel gantry - not the steel & AL extrusion style circa 2004+)

The long answer is, yes - it is possible, but you would have to give up one of your controller channels to pull it off & then 'shift' all axes up one. So the X in the back of the tool would be on channel 1, X on front would be channel 2 (normally siamesed to other X on channel 1), Y would be channel 3, Z channel 4. You would then have to code up & test out the routine on your machine to see if it works as planned.

Personally I think this is a waste of time & not the right road to head down. Get your mechanicals rock solid & there is no need for this type of routine.

-B

[garyc]

Ray...
I agree completely with Brady on this one. The OEM configuration has both X drivers sistered on a channel that match each other step for step. Giving that up for something that can usually be accomplished in a few seconds once a day doesnt make sense.