First time build - Steel Frame CNC Router

**JoeHarris** · 13-10-2016

Originally Posted by examorph

Thanks Joe, did you just do the single coat or did you have to go over it a few times?

Also, thank you for all the info in your build log, it has been a great help for both me and I bet many other members on this forum! I look forward to seeing your electronics come together as I am planning on a very similar setup and your schematics have already answered many of my questions! Did you use AutoCAD for these?

I think it needed two coats but I didn't bother taking the mill scale off - just went straight over the steel.

Be careful copying my schematic as it is yet to be proofed by the gurus!! I use Archicad...

**examorph** · 05-11-2016

After much hair pulling I think I have finally started getting my head around some of this electronics! Please could you guys cast your eyes over the attached schematic for me to ensure I don't see any of this rumored 'magic smoke' come from the electronics, or worse yet...my head?!

Most of its based on a circuit diagram Dean posted for another user a while back and connections based on various instruction manuals and confirmed against Joe's schematics. Some things I was unsure about were things like daisy chaining some of the wires (eg at the fuses/terminal blocks), if connecting shield wire earths in series on the limits was OK and if the alarm terminals on the drives only applied if using a safety relay?

Also, I know you recommended 6.1Nm NEMA 34 for the X axis but would I be OK going with the 8.7Nm instead as per Joe's build? As this would let me buy all motors from one supplier (CNC4YOU). Thanks.

Schematics

**examorph** · 05-11-2016

Forgot to mention, would the below enclosure setup be OK? I think I read somewhere that 600 x 900 was the typical recommended size for enclosure so will look for this, does anyone have any recommended suppliers please?
Schematics
Also, will this do for the drives: https://www.aliexpress.com/item/New-...2-5560f2d46d31
Or does anyone again have any alternative recommended supplier? Thanks!

**Lee Roberts** · 05-11-2016

Originally Posted by examorph

Forgot to mention, would the below enclosure setup be OK? I think I read somewhere that 600 x 900 was the typical recommended size for enclosure so will look for this, does anyone have any recommended suppliers please?

That was probably from me, 6x9 isn't as common a size and so was more an approximation (and a typo), adequate airflow is important to me and I think should be considered by others, plus working in an enclosure should be a pleasure not a chore.

6x8x3 would meet the needs of most I think: http://uk.rs-online.com/web/c/enclos...ng/enclosures/

Try and keep all power cables away from communication cables as best you can, use cable trunking to define 'zones' and then group components in each zone

**JAZZCNC** · 05-11-2016

Will look at this properly for you later but see one thing I'd change. Use contactor rather than relay contact for turning on transformer. Still use relay for safety but have turn it on contacter which is better suited to high current.

Also what kind of limit switch are you using.? On quick look if Proximity then think you have them wired wrong. If Prox what type NPN or PNP.?

**examorph** · 05-11-2016

Originally Posted by JAZZCNC

Will look at this properly for you later but see one thing I'd change. Use contactor rather than relay contact for turning on transformer. Still use relay for safety but have turn it on contacter which is better suited to high current.

Also what kind of limit switch are you using.? On quick look if Proximity then think you have them wired wrong. If Prox what type NPN or PNP.?

Thanks Dean, they are NPN proximity switches, I think you recommended these for another user http://www.ebay.co.uk/itm/1417817891...c=1&rmvSB=true
Another thing I noticed I had cocked up on was showing them as "limits" on the diagram, they are actually homes and I was planning on using soft limits within Mach3, will get the drawings updated showing this and the contactor. Thanks

EDIT: Is it also worth running the VFD through the same contactor as the transformer or should I keep that one running through the relay?

**JAZZCNC** · 05-11-2016

Ok had good look and only see few things would change.

First home or limits makes no difference to how wired and you had it wrong. See pic how to wire Npn correctly.
Now if you have the switch travel with the axis and sense target you can have one switch work has home and limits for that Axis. Just few settings inside mach3.

Regards the VFD then yes it would be better run thru contactor than Relay contact.
However personally I wouldn't Kill power to VFD just sending it stop signal is enough IMO. While strictly it's safer to Kill power it's also pain in the arse waiting for VFD to power up just because you put machine in Reset mode. It's personal thing really but IME it's more trouble than it's worth and spindle being forced into stopping is safe enough at DIY level. The Controller will also drop the Spindle output so stops anyway when E-stop occurs.

Next I would control the Water pump using the VFD on board Relay. This way the pump only comes on when spindle is spinning.

Fuse sizes for drives are too large. 5A is more than enough.

Edit: Noticed on pic forgot to change input numbers but you should get the picture.