Centroid Community CNC Support Forum

dmbgo wrote: ↑Fri Oct 02, 2020 2:33 am In hindsight, maybe I only needed to ground one end of the cable shield?

Typically you ground the shield on the control side.

Question, why did you choose to use an RJ45 block like that? Seems to me introducing another connection point invites trouble.
I terminate everything on the Acorn board whenever possible.

martyscncgarage wrote: ↑Fri Oct 02, 2020 10:21 am Question, why did you choose to use an RJ45 block like that? Seems to me introducing another connection point invites trouble.
I terminate everything on the Acorn board whenever possible.

I did it purely for convenience Marty. I had used an old network switch chassis when building the controller (the box suited) and I have had nothing but positive experiences with the RJ series of connectors. Albeit my experinces have come from a computer networking perspective. I do understand your point however - the less connections the greater the integrity.

martyscncgarage wrote: ↑Fri Oct 02, 2020 10:19 am

dmbgo wrote: ↑Fri Oct 02, 2020 2:33 am In hindsight, maybe I only needed to ground one end of the cable shield?

Typically you ground the shield on the control side.

Thanks for that, it vindicates my assumptions. I don't think I'll change it now that it is operating correctly though. Unless you think that I might have longer term reliability problems?

dmbgo wrote: ↑Fri Oct 02, 2020 5:18 pm

martyscncgarage wrote: ↑Fri Oct 02, 2020 10:19 am

dmbgo wrote: ↑Fri Oct 02, 2020 2:33 am In hindsight, maybe I only needed to ground one end of the cable shield?

Typically you ground the shield on the control side.

Thanks for that, it vindicates my assumptions. I don't think I'll change it now that it is operating correctly though. Unless you think that I might have longer term reliability problems?

Leave it,
Sometimes the shield causes issues. I can not explain why.
Marty

Thanks Marty

Well, after a bit of a break, whilst I did a few things around the house, I'm back in CNC land. The acorn is nearly ready to operate. I have wired up the coolant control to the acorn using one of the relays connected to the acorn board. This then switches 240v AC via a solid state relay inside the AC housing of the coolant pump. I have also roughly set the distance traveled per axis and backlash compensation. I'm nearly ready to try it but I think I'll put a few covers on first

Covers are on and I tried a basic turning job. I followed the steps outlined in the youtube video. All went well with the covers, but when I tried to turn a bit of bar, the Z axis didn't reverse, although the X axis behaved as expected. The net effect was to have the tool 100mm away from the workpiece when taking 10 x 10mm cuts. I thought this was perhaps caused by interference, so I added shielded connectors to my axis cables, but sadly no change.
Further fault finding :with the spindle running I am able to manually take cuts from a piece of stock by using the MPG, so I think there is an issue with the GCode, but I'm not sure what.

I just want to clarify that the Z axis behaves as if it is not getting the Dir signal. When I use the MPG it changes direction happily.

dmbgo wrote: ↑Wed Oct 14, 2020 8:12 pm I just want to clarify that the Z axis behaves as if it is not getting the Dir signal. When I use the MPG it changes direction happily.

Post the G code....
You should try and use INTERCON for your first G code.
Download the Lathe Manual and try the exercises listed under Section 8: Intercon.