My new 6040 improvement plan.

[Kev2960]

Hi there, the hose is a push fit (tightish) both onto the spindle and for the plastic hoover hose. I made it 0.1mm smaller than the dimensions on the drawing below. you can do this by reducing your cutter dia. Eg. cutter is dia 8.0 so tell the machine the cutter dia is 8.1
The material used is 12mm MDF

[PaisleyPCdoctor]

Here is the inside of my controller box. Plenty of issues to deal with.

NOTHING is earthed or shielded.

The VFD should bt even be in this box and the VFD output wires are draped right over the unshielded inputs of the controller.

Many if the power cables are undersized. Labelled as 1.5mm, but looking at them, I don't even think they are 0.75mm2.

Plan... rewire the whole thing. Shield and ground everything. Move VFD to seperate shielded enclosure...

[PaisleyPCdoctor]

That last post was from 2 days ago.
I've rewired and shielded everything.
Moved VFD to its own box.
Fixed a few electrical safety issues.
Pump switch removed. If the controllers on, cooling pump is on. Simple.

It's all technically sound, but I think I need to go back in later and make it a bit neater.

I also plan to replace the 24v fan with a 240v version.

I haven't decided whether to move VFD control panel to new VFD box or leave it there. I'll think some more about it.

[m_c]

Over the top springs to mind, especially since everything was working with no problems.

I'm sure you'll carry on with what you think is right, however I'm just posting for the benefit of anybody inexperienced who might read this and think that all this is necessary. It might reduce the chance of problems, but there are thousands of machines that run with unshielded wiring and VFDs inside control boxes, with no issues what so ever.

And if you really were doing everything correctly, your new choke/filter for the VFD should be mounted on a sub-plate, not directly to the case ;-)

[PaisleyPCdoctor]

And if you really were doing everything correctly, your new choke/filter for the VFD should be mounted on a sub-plate, not directly to the case ;-)

It's just the photo, it's not mounted to the case, it's actually suspended in mid air. With the stiffness of the wiring looms, it's not going anywhere.

[m_c]

It's just the photo, it's not mounted to the case, it's actually suspended in mid air. With the stiffness of the wiring looms, it's not going anywhere.

I never realised the ferrite ring was still mounted in that bit of the photo. I was on about the silver box mounted to the side of the enclosure at the bottom of the photo. Technically any power components shouldn't be directly mounted to the case, they should be mounted on a sub-plate.

As there's a ferrite ring, I wouldn't bother shielding any of the power cabling in the case. Ferrites are very effective at stopping the noise that can potentially cause problems. I would however use good quality shielded and twisted pair wiring for the VFD speed control wiring, as noise on that can cause spindle speed instability. The control wiring less so. It will all be 12 or 24V, and it would take a lot of interference to cause any problems there.

[PaisleyPCdoctor]

Good advice. Thanks. The control wires are all double shielded. The silver box you mentioned is an EMI filter for the mains inlet, but you are right, it should be on a sub board. Its earthed and so is the casing. I'm gonna leave it for now. Next time I rejig the innards, I'll move it.

[Doddy]

From personal (and expensive) experience with unsupported rails from one of England's finest CNC manufacturers of fluffy-dice, look at the amount of deflection you get over the x-axis travel, particularly if you ever fancy trying isolation routing of PCB (sounds like you're in that sort of ballpark), and also spindle rigidity.