Messages

3171

General Mach Discussion / Re: Transformer DIY qquestions

« on: August 07, 2014, 12:45:15 PM »

I suggest you connect your rectifier bridge first then measure the a/c voltage output (it is liable to be higher than 24V). Tot up the total current you will be drawing from this PSU (Steppers, relays etc. etc.) then you have the figures for your capacitor calculation. Also best to make certain that you are not going to try to draw more current from this transformer than it's manufacturers specification.  (should have kept the label)

Tweakie.

3172

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: August 07, 2014, 11:48:48 AM »

Hi Art,

I agree, the 4 – 5 power levels will not be enough. Just a thought but could you not just run at 10kHz and limit the duty cycle to 50% (the original plugin only achieves, at best, a 50% duty cycle at 12.5khz).

Quote from Synrad docs…
In most cases, the laser does not achieve full depth of modulation when driven by Command signal frequencies over 5kHz at duty cycles greater than 50%.

Scrub that thought - it would not enable more power levels in just half the band.

However, I don't understand quite how you are going to do it but I like the idea of byte streaming power levels.    External PWM generator ??

Tweakie.

3173

General Mach Discussion / Re: Transformer DIY qquestions

« on: August 07, 2014, 02:54:29 AM »

No problems using the toroid at 60Hz.

The capacitor value is calculated from :-

C  = (80,000 * I ) / V

C=uF, I=amps, V=volts

Watts = Volts * Amps

Tweakie.

3174

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: August 07, 2014, 02:08:47 AM »

Hi Art,

That Gearotic laser control looks like a very interesting project indeed and I look forward to following your progress.

Regarding the engraving plugin you may be interested in work by TomTom in Japan - he has produced raster and vector plugins (based on your original engraving plugin) and these videos relate...

https://www.youtube.com/watch?v=o-BHEPkvaVI

https://www.youtube.com/watch?v=5L_xaxfXNjM

Tweakie.

3175

Show"N"Tell ( Your Machines) / Re: DC-K40 Laser conversion issue

« on: August 06, 2014, 10:32:38 AM »

My advice is to take the connection directly from the PSU GND to the LPT GND not going through the spindle relay.
If you need to use the spindle relay then take the interlock protection circuit through the spindle relay.

Tweakie.

3176

General Mach Discussion / Re: Mach3 precision error but not skipped steps

« on: August 06, 2014, 04:24:12 AM »

Just a shot in the dark but I would be inclined to thoroughly check for a mechanical fault in the machine - the problem of loose grub screws comes up quite a lot also flexible couplings slipping etc. etc.

Tweakie.

3177

Show"N"Tell ( Your Machines) / Re: DC-K40 Laser conversion issue

« on: August 06, 2014, 01:56:52 AM »

Hi Guys,

It sounds to me like you are experiencing a difference in potential between the GND connections between your computer LPT port and the machines PSU GND.

The LPT port’s pins 18-25 are GND and one of these pins must be connected to the laser PSU’s GND point (adjacent to the TTL(L) signal input as shown in my earlier diagram),

This should resolve the problem of the laser firing when it should be off.

Tweakie.

3178

General Mach Discussion / Re: Slow axis feed rate is too fast

« on: August 04, 2014, 03:46:59 AM »

I think the default is 80%

Tweakie.

3179

General Mach Discussion / Re: Slow axis feed rate is too fast

« on: August 04, 2014, 01:47:33 AM »

Pressing the Tab key brings up the pendant - reduce the Slow Jog Rate % 

Tweakie.

3180

General Mach Discussion / Re: Slaved stepper not moving the same amount???

« on: August 03, 2014, 06:22:20 AM »

I will be ordering a new stepper, but this one has 4 leads and the new one of the same model
that Oriential sells now has 6 wires...will it be compatible with the other 4 wire, or do I need
to buy 2 new ones???

Hi Preston,

I don't know if this helps...

Tweakie.