Here we go again . . . MK4

**Clive S** · 07-10-2018

Awesome as always.

**Zeeflyboy** · 08-10-2018

Looks awesome! Getting really close to being finished now I guess?

You must be extremely proud - it's going to be fantastic.

**routercnc** · 09-10-2018

Sorry been away from the forum again
Thank you Clive, Bert, Zeeflyboy for the kind words. I’m very pleased to get this far and have tried to make the best machine I can.

Yes I have motion at last but there is a list of tiny jobs to sort out including:
Proximity switch mounting and wiring in for both home and limit functions
Proximity switch targets
Z home proximity bracket
Small connecting brackets to finish the gantry installation
Rewiring the spindle back to a removable plug with a longer cable which goes through the energy chains this time
Water cooling pipes, tank and pump fabrication and installation
Lighting
Mist spray
Belt guards
Mag base mounting plate on Z axis for DTI
Mounting the spindle
. . .
Skimming the bed
Squaring the gantry and getting the home switches on X axis aligned
Tramming the spindle using the adjustment screws

I think that is it?
Then let’s see what she can do !

**Vulcano** · 14-10-2018

Sorry for my language - i think is not a perfect (Nederland)
Im very interesting of your router CNC - is it possible to send plans for me via email ??

**routercnc** · 15-10-2018

Originally Posted by Vulcano

Sorry for my language - i think is not a perfect (Nederland)
Im very interesting of your router CNC - is it possible to send plans for me via email ??

I don’t have detailed plans that someone could follow. I’ve made changes along the way and it is quite a complicated machine.
However I plan to put overall dimensions in a future video as a start point for other people to start their own design from.

**routercnc** · 05-11-2018

Episode 22 is now ready . . .

**Zeeflyboy** · 05-11-2018

Looking awesome as ever - looking forward to seeing it at work, it should be a beast!

**routercnc** · 05-11-2018

Originally Posted by Zeeflyboy

Looking awesome as ever - looking forward to seeing it at work, it should be a beast!

Thanks Zeeflyboy. Good thinking, maybe I should call it El Beast ? 😋

Enjoying your beautiful build also, great work.

**1nbcnc** · 07-11-2018

I have been following along your build, it is really inspiring and also your gantry rigidity spreadsheet helped out a ton in my design, thank you! I do have a question, I noticed in episode 22, your spindle connector is not the original connector that came with, it's got a strain relief, can you point me to where I can find those? I've searched on McMaster and no luck. I know it is metric, do you happen to have the dimensions? I measured it, its something like M19x1 thread and 22mm OD. Any guidance would be appreciated, thank you!

**routercnc** · 07-11-2018

Thanks 1nbcnc. Glad the old spreadsheet is still helping people out to get a feel for it all.

The original connector plug that came with the spindle was either GX16 or GX20. Certainly that style anyway. It was many years ago so can't remember if it was 3 or 4 pin. I think it was 4 and only 3 pins were used in the socket on the spindle side (going to the 3 windings in the motor). I added an earth cable from the spare 4th pin on the spindle side to one of the screws behind the end cap and used 4 core CY shielded cable to wire it up to the VFD. Note there is not really any strain relief with the GX16/20 connector.

This all went well for many years until one day there was a large blue flash from the connector and it damaged the VFD beyond repair. After years of use the repeated movement of the cable pulling at the connector plug it had loosened the pin connections and it arced. This is fatal for VFDs as they must not see a spindle disconnect when running.
Adding a strain relief above the connector had been on my to-do list, but you know how it is, just one more job to cut and then maybe I will get around to it. Well, it served me right.

So after that I wired the cable DIRECT to the windings, including an earth, and added a cable relief grommet which passes through the hole in the cap and has a nut on the back. 22mm hole in the end cap rings a bell but I really can't be sure as it was many years ago. This is what you saw in the video, the old strain relief grommet. What you then saw me do in the video was replace this with a longer cable, but it is still DIRECT wired to the spindle with the strain relief to manage the stress. This means it cannot be quickly disconnected.

It is similar to this one, but I think it might be a bit larger. Next time I am out in the workshop (sorry, not this weekend and at least the following weekend) I will see if I can measure anything although the spindle is buried in the Z axis.
https://www.ebay.co.uk/itm/Spiral-Ca...UFt:rk:18:pf:0

Many on this site would recommend fitting a removable connector AND strain relief after it, and I would not argue against it. However, I've had no cause to remove the spindle, and I know with the direct wiring and long strain relief grommet it should run OK for a long time. Hope this helps.