Ajax CNC Mach3 3-axis mill conversion thread

[skyg]

Really getting somewhere now! The board is now mounted in the cabinet. We had to move the servo drives to make everything fit, but save for wiring up the e-stop, all the physical installation is now done. Since the old cables were not shielded or terminated correctly, I redid all the encoder and motor cables. Overall, just the reduction in wiring in the cabinet has been huge over the old setup.

I'm getting ready to hook up the Baldors to the GPIO4D. Scott could you please take a look at the Baldor manual I have posted above one more time? If you look at page 16 of the manual there is an input schematic. My best guess as to how to hook up the GPIO4D to the Baldor is as follows:

GPIO4D------------>Baldor TSD
Axis Analog------->Differential +
Analog Common-->Differential -
Enable Output---->Enable
Output Common-->Common

Does that make sense? Also, should those wires be shielded?

-Sky

[diycncscott]

Hi Sky,

I was on the road for a few days, sorry for the delay.

Yes, it looks like you have the wiring correct. You should use shielded, twisted pair cable for the analog signals.

[skyg]

Okay great! And what should I tie the shield to? I know it should be grounded of course, but not sure if any of the ports on the analog output would work.

[diycncscott]

Hello Sky,

Connect the shield to the analog common for that axis on the GPIO4D

[skyg]

Thanks Scott!

[skyg]

Okay I've got everything now connected and I'm starting to get all the drive settings dialed in. So far it's working pretty good, although it took me a while just to find settings that would keep the axis stable and not just start oscillating in place, or once I initiated a movement. One question thus far:

The plot graphs I'm generating don't seem to be as "smooth" as the ones in the manual - that is there does not seem to be as many data points. Is there some way to increase the sample rate that the plot brain runs at?

I can post the files if need be tomorrow.

-Sky

[skyg]

Well I spent more time today getting the mill dialed in, and I'm making progress. I've got it running g-code, but I've got the following issues I still need to resolve.

1. Step jogging works fine, but continuous jogging does nothing. I'll toggle from Step to Continous mode, click the buttons on the screen (x+, x- etc) and no movement.

2. Likewise, when I click Ref All Home, nothing moves. Nothing at all. I'm guessing these two issues are related, but not sure.

3. Another most likely related issue - sometimes after running g-code, step jogging ceases to work. If I close Mach3 and then restart it starts to work again. For jobs where I have to do a manual tool change, this could be a problem.

4. I can't dial in the motion in the z axis, because the plots it generates are different from the ones that the x and y axis generate. The parameters are different on the left side of the plot screen. Looks like maybe it's setup for a lathe or something like not, not a mill axis.

5. Sometimes I get a lot of clicking of (what I'm guessing are) the relays on the GPIO4D, especially when I first reset Mach3. Say, I might get 5-10 "clicks" in ~10-15 seconds. Should I be worried about this?

Even with these issues, I can already see that I should be able to run the mill between 300 and 500 ipm when it's fully dialed in. This is truly excellent - with the Galil I was roughing at 120 ipm and finishing at 80, so roughing at 500 and finishing at 300 is a massive improvement.

-Sky

[skyg]

Okay I ALMOST have all these issues resolved. Here's where I'm at:

1. I realized that continuous jogging is with the arrow and pg up and pg down keys (as per the manual) and I actually like that more than the on screen buttons.

2. Again, reading the manual, I now realize that homing is via the MDI. The X and Z axis home perfectly, however I am having a problem with the Y axis. The Y axis does not move off of the home position - it trips the home switch and then simply stops. X and Z work perfectly, so I'm not sure what is causing this, maybe some problem with the script???

3. I figured out how to display the data correctly in for the z axis, although it still is a different screen than the X and Y. The z is now more dialed in than before, still have to tweak it some.

Scott I just need help with the homing issue - what could be causing the Y axis to not "bounce" off the home switch?

-Sky

[cncsnw]

On the Machine Configuration, Motor parameters screen: do you have the same input numbers entered for minus and plus home switch inputs as you have entered for minus and plus limit switch inputs?

If not: if, for example, your minus and plus limits are entered as 4 and 3, while your minus and plus homes are entered as 3 and 4, then when you tell the control to home the axis plus it will move plus, looking for INP4, but when it trips INP3 it will interpret that as an unexpected limit.

Are you able to slow jog off of the tripped limit, or do you have to turn the axis by hand to clear the switch?

If not, then you may need to swap wires between the plus and minus switch inputs (and make the corresponding changes to the input numbers entered on the Machine Configuration screen).

[skyg]

I'm a little confused as to which screen you're asking about about, since there's no switch input selection on the motor parameters screen of Mach3. I'm going to assume that you're talking about the Ports + Pins -> Input Signals screen, correct? If so, here's what I've got:

1. Y Home is on Input 11, Y++ is on input 4, Y-- is on input 3. When I trip each of the switches on the mill, the appropriate light comes on in the Diagnostics tab.
2. When I home the Y axis, ONLY the Y Home light comes on in the Diagnostics tab. It lights up, and then the axis stops moving. The Y-- Limit is not triggered at all during homing.
3. Yes, I can jog the Y axis off the home switch to clear the Home light.

-Sky