Messages

81

General Mach Discussion / Re: Charge Pump & Mach 3

« on: May 23, 2012, 06:38:59 PM »

You can use an earphone to detect the 12.5khz signal but detecting dropouts or intermittent errors is out.
If it fails for some reason such as a software bugger-up, will it stop altogether or recover itself?

82

General Mach Discussion / Re: Can you help me make 2 identical components in one sheet?

« on: May 17, 2012, 08:44:38 PM »

Why would you bother? Write the cutting part as a subroutine, use two fixtures, cut one part then change fixtures and cut again. Five minute job to code that.

83

Show"N"Tell ( What you have made with your CNC machine.) / Re: Using Biodiesel as a machining fliud - Video

« on: May 07, 2012, 10:24:20 AM »

if it is vapourising and making "smoke" then it will be at or above its flashpoint. If any portion of the work sparks or becomes incandescent there is a high risk of a flashover.

You can get vegetable based water soluble coolant - Ometa make it in various flavours.

As an aside, i used to run my old diesel Escort on waste vegetable oil, it smelled of kebabs and nasty meats but it worked surprisingly well. the cost of fresh veg oil and indeed used veg oil in the UK has murdered any chance of saving money by making biodiesel but WVO can still be had for running as a straight fuel.

84

General Mach Discussion / Re: parallel port help

« on: May 06, 2012, 08:18:35 AM »

Nice to have, not essential. You can pick up the safety pulse on pin 1 using an earpiece for example. And a 20 year old scope in good condition would be fine.

Do you have the port address set up properly?

If the chipset really won't play then an add- on parallel card may be the answer . We find the Moschip based cards work very well for our purposes.

85

General Mach Discussion / Re: parallel port help

« on: May 02, 2012, 05:33:00 PM »

You will see it better on an oscilloscope if you have one, can you get a clean on/off output at the spindle's assigned pin?

86

General Mach Discussion / Re: help please

« on: April 26, 2012, 07:53:58 AM »

check your wiring and switches for cracks, damp and coolant, any conductivity will show up as a triggered switch and drag the pin voltage down.

87

General Mach Discussion / Re: touch probe drawings

« on: June 26, 2011, 07:44:56 PM »

http://www.machsupport.com/docs/SW_Digitising_Probe.pdf

Looks like it should work.

I'm designing my own with an overtravel switch which will kill movement by triggering the limit circuit.

Probing and overtravel need two conductors each in the cable, I would suggest using a six-pin connector at the machine and fitting a dummy connector to it when not in use. The dummy connector has all three pairs shorted (1 to 2,  3 to 4 and 5 to 6) to enable normal operations. pair 5-6 enables the spindle and the probe's cable has these permanently open to prevent the spindle running when the probe is attached. This is my strategy. If and when I get the thing developed fully I'll share the results here.

88

General Mach Discussion / Re: Are people getting emails sent to them of resopnces they made in a post ?

« on: June 25, 2011, 05:28:59 AM »

awesome thread necro btw. Going on six years. 

89

General Mach Discussion / Re: Are people getting emails sent to them of resopnces they made in a post ?

« on: June 24, 2011, 09:12:34 PM »

Mine was working a couple of days ago.

90

General Mach Discussion / Re: Spindle speed fedback?

« on: June 20, 2011, 10:07:38 AM »

Shame

Hope you're feeling better by the way.