Messages

71

LazyTurn / Re: LazyTurn

« on: August 02, 2008, 10:55:23 PM »

Some nice pieces there thanks. Not having done many DXF to Gcode conversions (read this as none)  how would you know by downloading a DXF if your 3 axis mill will be able to make it once Mach 3 has got hold of the DXF and converted it? The Knight looks a little tricky with 3 axis.

72

LazyTurn / Re: LazyTurn

« on: August 02, 2008, 09:24:53 PM »

I see various mentions of cutting chess pieces with LazyTurn how would you do the knight? Is anyone going to be kind enough to post a set of G-codes to make a chess set? I'd like to make a shiny stainless steel set one day for the father in law as he's a keen chess player and would really appreciate a personal set like that's especially on an inlaid chess board. << dreaming of projects to come......

73

Video P*r*o*b*i*n*g / Re: More hands..

« on: August 02, 2008, 09:16:33 PM »

You've had a nasty break on that thumb of yours at some point . Are you actually scanning your hand or some plaster model of it ?  Would coating the surface of the object being scanned with something help? Even something like talc to try and stop rogue reflections?

74

Show"N"Tell ( Your Machines) / Re: Warco VMc /Chester 626 knee mill CNC conversion

« on: August 02, 2008, 09:06:02 PM »

Splendid on the taper thingys it would save a bit of hassle if I dont get them pre keyed.
I've got all my bits and pieces in a box today. I found an old rack mounted PC case in a skip which is ideal as it has a couple of big fans and an ATX power supply to power the BOB's. The smoothstepper, 2 X BOB's, 3X stepper drives(MSD542's) and the motor PSU all fit in nice and neat in the one box. I'm thinking of connectors now for the leads to the motors. I'm connecting the 8 wired motors in parallel so I'll only need 4 cores to each motor. So I'm thinking of what kind of connectors I can mount in the rear panel of the new box which will be OK at 4.2 amp. The idea being it will make the system neater and if I then mod my lathe which I hope to do once the mill is sorted then I can unplug the Mill from the control box and simply plug in the lathe. I could go for a connector that has enough pins to take all the motors and a few extra for home and limit switches but this means them being pretty close to each other in the plug and seeing the problems people have had on here with cross talk and noise I'm thinking individual plugs with screen cable for each motor and another one for switches.

75

General Mach Discussion / Re: What is a CHARGE PUMP?

« on: August 02, 2008, 08:45:10 PM »

And do I need one?

Depends what system you've got and how it's set up but in my opinion anything that is connected to the parallel port of a PC needs one or something similar. If you can remember the days when a printer was actually connected to these ports everytime you switched the computer on the printer would burst into life for a few seconds then go quiet again. This was due to port testing being done as the PC got ready to do work. So if you now connect a bit of drive circuitry and a motor to the same port then the likely hood is it will also burst in to life in an un predictable manner every reboot of the PC. The other big problem is PC crashes, during this time everything or nothing maybe being whizzed out the printer port and obviously again the motors may act in a dangerously unpredictable manner. The gents above have described how the charge pump works quite well so I'd just add this. There is a part of the mach software that ensures there is a 12.5KHz signal on a pin of the parallel port whilst it has control of the PC and the port the chances of this 12.5KHz signal appearing during reboot or PC crash is v v unlikely so it is a safe way of ensuring your motors only receive a signal to move when Mach has control.

76

General Mach Discussion / Re: Spindle RPM

« on: August 02, 2008, 07:20:00 PM »

Breezetools, It looks from the picture of your mill that it has already been set up as a CNC and thus the spindle problem should have already been checked as working. Did it originally come with Mach 3 and a PC or are you trying to convert it ? Is the motor 3 phase ? or single phase ? If the only problem you have now is it turning the wrong way and it is a three phase motor then all you need to do is to swap two of the phases over.

77

SmoothStepper USB / Re: Welcome to SmoothStepper forum.

« on: August 02, 2008, 07:01:25 PM »

Thanks for the confirmation Hood. I was pretty sure but I always think it's worth asking.

78

SmoothStepper USB / Re: Welcome to SmoothStepper forum.

« on: August 02, 2008, 06:59:59 PM »

jhicks,  I haven't got any experience on small VFD but I have worked on some pretty big ones (several MW's) with once per rev probes providing feed back etc and we had a problem with spurious triggering of the input devices. This was eventually traced to the screening of the cables being earthed both ends over a fairly long run and thus setting up circulating currents in the screen that then appeared to act as some sort of transformer winding. Anyway If all your cables are screened try and keep them physically as far apart as possible and only earth them one end, I would suggest the controller end. You could also use some parasitic beads on supply cables etc (not on any high speed signal cable as it will distort the signal).

79

Show"N"Tell ( Your Machines) / Re: Warco VMc /Chester 626 knee mill CNC conversion

« on: August 01, 2008, 03:49:28 PM »

I don't pretend to be any kind of expert on pulleys except that I realize a different number or letter could mean a belt or pulley wont fit.  I'm wondering now then If I should have told BSL and AFC that anything near 10mm would be good enough I basically gave them the spec from HPC thinking these things are fairly standard I hope they don't waste a lot of time trying to match the belt sizes etc exactly. For taper lock I assume you get a standard taper lock adaptor and the pulley fits on it as in the gents pic on this thread. It's another option to think of.

80

SmoothStepper USB / Re: Welcome to SmoothStepper forum.

« on: August 01, 2008, 03:19:54 PM »

Quick question do I still need a charge pump with a smoothstepper? My thoughts are, as the smoothstepper remains dormant until the correct driver has established communications with it and the software is downloaded. It should be pretty bomb proof and thus highly unlikely to give spurious outputs on power up or PC problems. Are my thoughts somewhere near the mark ?