Messages

171

General Mach Discussion / Re: Homing limits and annoying Estops

« on: October 14, 2009, 08:28:01 AM »

Sounds like a clever man's scope, regardless of cost. nice going

172

SmoothStepper USB / Re: Hissing noise from Idle Stepper Motors with Smoothstepper

« on: October 13, 2009, 06:21:56 PM »

my mill steppers hiss, I'm using a Routout stepper drive off two paralell ports. Doesn't seem to cause any harm.

173

General Mach Discussion / Re: Homing limits and annoying Estops

« on: October 13, 2009, 06:16:31 PM »

Could be my old friend, the damp and gummy wires.

See if your breakout board will trigger a limit event with a 100K resistor across the terminals. Also measure the "normal condition" and "triggered" resistance of your home switch circuits and compare results.

A quick way round this is three 5v coil relays arranged to be triggered from the limit switches (or one relay if using a continuous loop). This has its coil driven by a seperate power supply (a phone charger is good) through the home switches, so they only trigger the realy with the sort of current a closed switch can provide, not little leakage currents. The relay contacts drive the breakout board, so it sees either clean, dry open contacts or a dead short - no funny business in between.

174

General Mach Discussion / Re: Dell PC any good ?

« on: October 13, 2009, 06:02:35 PM »

what's the machine spec on the old Dell? mine is a no-name 900MHz PC that was due for the bin years ago. If yours is anything like a standard PC is should work ok. If it has a parallel port it should work like one. Are you using a breakout board to attach the machine to the computer? This is often a good way forward in order to get a strong signal out and tolerate gummy machine wires. In short we need more information.

If your port is really rubbish you can get PCI parallel port cards for not much. mine use a Moschip chipset and work very well.

175

Show"N"Tell ( Your Machines) / Re: Ex-Cell-O Spindle Wizard to retrofit

« on: October 11, 2009, 04:42:43 PM »

Very nice setup! well done.

just a word of warning about expanding-sheave drives like that, we took an XYZ drive apart a few years ago and the spring leapt out and smashed a big chunk out of our workshop wall. Best to be careful Obviously you've got away with it so fair enough.

176

General Mach Discussion / Re: Feedrate override for dummies? Please?

« on: October 04, 2009, 03:18:01 PM »

^^ and they're much cheaper

177

Show"N"Tell ( Your Machines) / Re: my first ever cnc machine build

« on: October 03, 2009, 05:29:02 PM »

Could well be my computer, most people would consider it inferior for the task of propping a door open. it'll just about run a CNC mill

178

Show"N"Tell ( Your Machines) / Re: my first ever cnc machine build

« on: October 02, 2009, 06:18:15 PM »

I have trouble with my PC and USB memory drives. I can be running a program held on the C drive and the steppers will bang and freeze and do all sorts of nonsense while the flash drive is plugged in. Not sure about mice but I'll keep using my serial mouse for now. it works so i won't fix it.

179

Show"N"Tell ( Your Machines) / Re: My first CNC project

« on: September 19, 2009, 11:00:07 AM »

Tidy job! Old scientific equipment tends to be really well made, and fairly simple to work with if all you're doing is converting it to something else. Good going

180

General Mach Discussion / Re: Orac Lives

« on: September 18, 2009, 06:29:55 PM »

Very nice and neat - Well done