Re:Dahlgren Engraver Z axis air actuation
I think you could use a C37 relay board and a power supply such as a A3 both from cnc4pc.
If there is a spot where you can safely connect to an output pin from the parallel port on the board you can use that as the signal to the relay board.
If not as John said just add a second parallel port card and use that to control the c37 to control your 5 volt relay.
There is a lot of info on parallel ports here
Thanks for info and link to the c37 board from cnc4pc.
I wonder if the C9 board would be even better, it uses solid state switching instead of mechanical relay. My thinking is the mechanical contacts might not last long due to the rapid and frequent cycling of tool up/down. A CNC engraving of text would likely have hundreds of cycles.
I will probably order today, although I hate to wait for it to arrive. I was hoping to wire up something myself today from local Radio Shack parts.
This Saturday is a rare time I have "off" to play with this hobby.
I will study it closer and maybe wire up something of my own today.
the relay board from cnc4pc suggested by Rick G looks good and would be easy.
While I am waiting for it to arrive I might try building my own circiut.
I was just looking at the skematic for my HobbyCNC EZ Motor driver board and wondered if the 6 output wires that would go to a stepper motor could instead be used to trigger my relay?
I already have 9-pin connector on my enclosure where the Z stepper motor would (will) plug into.
sure would nice if I could just wire up a custom 9-pin cable to plug relay into there.
Then when I eventually get z axis motorized I could just plug stepper back in there.
I don't have any idea what comes out those wires to power the stepper, so this might be a really stupid question.
Don't steppers have coils that are energized like a relay coil?
I can easily adjust the amps output to motor... I am guessing relay coil would required less than stepper.
From the IRC
can a stepper output be used to turn on a pneumatic solenoid?
[11:24] <skunkworks> I think you just would not know what sequence the stepper coils would be in.
[11:24] <skunkworks> at any given time
[11:24] <pcw_home> I guess I could but you need to know which winding is energized, easy for quadrature not for step+dir
[11:24] <pcw_home> ha SW beat me to it
[11:27] <pcw_home> quadrature = "wave mode" = stepgen mode 2
If you have a suitable Z-scale and no microstepping you could potentially use a 2-pole relay controlled from a stepper phase with one relay pole controlling pneumatics and the other acting as a limit-switch. Then by careful choice of the home-switch location in the iNI it might be possible to have the axis home to Z=0 (relay open) in such a way that Z=1 is a position with the relay closed. Then the G-code would simply need to contain Z0 and Z1 commands to open and close the relay.