Messages

191

General Mach Discussion / Re: Mini-Mills - any good???

« on: February 08, 2016, 09:00:05 AM »

direct answer to your thread title/question - I wouldn't really regard any of those you list as mills. They're all routers really whatever their quality or lack of.

I saw a comment once on the uk site which I think sums things up quite well. It went something like: "Any router will eventually scratch its way through ally - that's not to be confused with milling though".

192

General Mach Discussion / Re: Physical buttons for plasma

« on: February 08, 2016, 08:52:54 AM »

bloody noisy things these steppers

I kinda like it - singing a little tune as they go bless 'em.

Nope - as written, the pause thing makes no sense to me either.

193

G-Code, CAD, and CAM discussions / Re: Macro for inputs and outputs

« on: February 08, 2016, 06:51:46 AM »

Ok - been playing with it.
When I load your macro it doesn't wait for anything... just runs !

If by "just runs" you mean it turns the output on and then straight off, then you have a problem with your input signal. The first loop runs whilst the input is active and the second whilst it's INactive.

It therefore must be BOTH in quick succession. Either your input isn't doing what you think - or it's bouncing.

194

General Mach Discussion / Re: Physical buttons for plasma

« on: February 08, 2016, 06:09:06 AM »

No worries. TBH I've used around 3Nm steppers for all the axis on routers, plasma tables I've ever built. One stop shop - can't go wrong. (Sorry if I'm teaching granny to suck eggs here but as you're a servo guy - if you go steppers make sure you go for around 3mH inductance).

195

General Mach Discussion / Re: CNC router shudder and jerky / jitter doing 3D toolpaths

« on: February 08, 2016, 06:02:52 AM »

I create all of my geometry in Mastercam X4 and it also writes the GCODE as well. It seems to put out BOTH the G64 and G8 codes. I don't understand why it is doing this. It is saying; use CV MODE, then turn off CV MODE.

I don't use Mastercam but my guess would be that if you post your post file someone here will be able to take out the offending G8 line.

I also have no clue why Mastercam is producing so many lines of code. Could it be that my geometry in Mastercam X4 is fine but my post processor in Mastercam is what is writing the excessive amount of code lines?

Could be either or a combination of both I suppose. Regards the sudden change though, my guess would be your CAD geometry is suspect. Did you create it from scratch or did it start out life as a .dxf profile? That said though - if it's cutting ok now (with the G8 removed) - why worry.

196

Tutorials / Re: cnc pdf tutorials

« on: February 07, 2016, 12:44:25 PM »

A lot can happen in 7 years 

197

G-Code, CAD, and CAM discussions / Re: Macro for inputs and outputs

« on: February 07, 2016, 12:06:12 PM »

Blank lines are completely irrelevant.

Just copy it and try it

198

G-Code, CAD, and CAM discussions / Re: Macro for inputs and outputs

« on: February 07, 2016, 11:03:00 AM »

Try this:

Code: [Select]

ActivateSignal(OUTPUT1)

while isActive(INPUT1)
  sleep 10
wend

while not isActive(INPUT1)
  sleep 10
wend

DeactivateSignal(OUTPUT1)


199

General Mach Discussion / Re: CNC router shudder and jerky / jitter doing 3D toolpaths

« on: February 07, 2016, 05:18:01 AM »

Now this seems to have solved my issue but I am left with a couple questions:

1. What should I have turned on in relation to CV MODE (other than CV MODE)?
2. Do I need 4000 pulse/rev for microstepping or is there a better amount to use to optimize my system?
3. Is there any other things (settings, etc) you folks can think of to help make my system run smoother?
4. Why does my GCODE turn off CV MODE?
5. Should I always have CV MODE on?
6. How can I program Mastercam to always input a G64 into my GCODE?

1. Nothing if you can help it. All the CV settings cripple CV to one extent or another.
2. Unlikely - 2000 p/rev would be more normal. (caveat - I know zip about those fancy dandy servo type drives).
3. I'd be looking at why your CAM produces so many lines of code. It seems excessive to me. Are you for example converting arcs to lines unnecessarily? Also take another look at the pic I posted, why have the lines suddenly changed from around 3 hundredths to 7 thousandths for no apparant reason?
4. I think this one's been done...
5. Pretty much - unless you have good reason for turning it off - and then you'd want to look at 1. again first.
6. Looks like it does already - you need to stop it sticking the G8 in afterwards.

200

General Mach Discussion / Re: CNC router shudder and jerky / jitter doing 3D toolpaths

« on: February 06, 2016, 09:34:46 AM »

Re: the great micro-stepping/torque myth/truth debate - crikey this one runs doesn't it? - 

How about a PRAGMATIC approach?

Micro-stepping a) increases resolution (up to a point) and b) reduces resonance.

Re: a) - more than 10 is pointless. The argument goes something like this: A stepper has a full step accuracy of +/-5% or a 10% swing. That means it's accurate to within 0.18 degrees. That just happens to be the resolution of factor 10 microstepping. So, how can you increase resolution beyond the accuracy its capable of? - answer: you can't it doesn't make sense.

Re: b) - We're running full step or perhaps low micro-stepping and we get resonance. That resonance builds up and results in a stall. Stall happens when torque is zero. We increase micro-stepping. It no longer stalls. Which therefore has the most torque?