Tiddy CNC.

[Clive S]

You could put a pot on the vfd front panel to control the speed if its the standard Chinese one. ..Clive

[Clive S]

Fitting a pot to a vfd.

Here is the link to the way I did it http://www.mycncuk.com/threads/7388-...ighlight=speed ..Clive

[TonyD]

Great Thread, thanks Clive.

[TonyD]

I have two NPN NC bullet type proximity switches on my X Axis. Normally the inbuilt LED lights up when the target metal approaches and triggers the switch. As of last week, one of the proximity switches is lit the whole time, I cant change its state. Mach is reporting the error when I try to home the X axis. I've run a new switch to the same connectors as the faulty one and the new switch stays lit also. Note, in case it matters both switches were in parallel during this test. I can't spot any obviously loose wires in the control box. Before I start to tear into the control box, has anyone experienced this type of failure mode from the proximity switch before? Cheers. Tony.

[EddyCurrent]

Have you tried them on another input ? are they 3 wire or 2 wire type ? 3 wire likely.
Did you change the position of them so the end is more flush with the surrounding bracket ? (what I mean is that's a bad thing)

[TonyD]

Hi Eddy, thanks. 3 wire, I'll change the input and report back, no - no adjustment, cant see a good reason for the signal stage and the proxy in paralell shouldnt have triggered either it was hanging in mid-air, I should have said that too.

[TonyD]

OK, turn out that the PX is actually behaving fine, its the other X Axis one thats dead, ran a new one in parallel and that one works as advertised so I'll just swap the dead one out. Sorry for the confusion. Tony.

[TonyD]

Also, for those who are thinking "I thought those Px switches were reliable", they probabily are, the two I have on my X Axis have little dents in the front, no doubt from an impact with the X Axis! So no surprise that at least at one of them failed :)

[Clive S]

Also, for those who are thinking "I thought those Px switches were reliable", they probabily are, the two I have on my X Axis have little dents in the front, no doubt from an impact with the X Axis! So no surprise that at least at one of them failed :)

Tony can you remount them so that the target slides over the end instead of crashing into it. ..Clive

[TonyD]

And for my next problem.. :)

So things are generally going well but very slowly. I was nicely surfacing the MDF bed of the machine but saw one of the ball screws coming away from the coupling so a good spot of tightening up was carried out and I am much more confident that wont happen again. Having created infeasible amounts of dust and also realised that the Cambam feed was set way too low I have paused to consider some options. Firstly the dust is a problem so I've got some parts on order for a cyclonic dust extractor into my Aldi ash bin and I think I'll be OK to machine some acrylic for a dust shoe but I digress...

I thought I'd add tool auto height. I read the threads, set up the inputs and did the wiring which (as its probably) relevant was just two wires from the BOB input to a set of crocodile clips one for the tool for now and one for a little plate. All was well and I tested it by touching the probe to the plate in my hands to make sure the Z retracted and it did, ... the joy :) so then the real test and as soon a I connected the crocodile clip to the end mill in the spindle the Pilz tripped out. Not the RCD's the Pilz. So, I guess its an earthing issue but without me having to draw up a wiring diagram, has anyone experienced this type of thing before? Thanks in advance chaps.