Topics

1

Mach4 General Discussion / When is a rectangle not a rectangle?

« on: April 10, 2022, 09:48:15 PM »

Hi Folks,

I've been using Mach4 on my CNC for ages but yesterday the following happened.

I was just trying to cut a simple rectangle 300mm by 110mm by 18mm deep using a 6mm bit.

this forum is really crap at loading images but:
IMG_1 is the regened toolpath. It's clearly a rectangle

IMG_2 is the g-code. It's clearly a rectangle.

and IMG_3 is what it cut. Now its a rectangle with one corner rounded off (top right)

What the hell? It did it on purpose as it did the same thing on all 4 passes.
I'm at a loss as to why it did it - anyone have any ideas?

2

Mach4 General Discussion / Why does the roadrunner.tap have an M99 at the end?

« on: March 12, 2015, 07:56:42 PM »

Hi Folks,

starting to get the hang of this finally and I've managed to get my mill to run roadrunner.tap and get the expected results.
But I'm curious as to why the gcode has an M99 at the end.

It makes the entire file run again from the top.
Wouldn't an M30 be more appropriate or is it looping for a reason?

I don't have an endmill in place yet, just a pen, so maybe it's increasing in depth or something but it doesn't look like it is.

I think once I get all this sorted I'll write some simple calibration gcode files for beginners. I know I would have loved to have found some.
Although, now I've mentioned it, someone will probably point me to some. 

3

Mach4 General Discussion / MDI movement using G-Code different to jogging

« on: March 08, 2015, 11:30:16 PM »

Hi All,

I am finalising the setup of my new machine and have discovered something I don't understand.
I have setup a pen where my end mill will be to test that all works correctly.

If I set the pen on some paper and zero all axis I can draw a perfect 2 inch by 2 inch square by just jogging the X and Y axis to 2.0 and back while watching the RDOs.
I assume this means I've managed to set the motor and axis parameters correctly.

So I moved to issuing MDI G-code commands to start learning what is what.
But if I, again, put the pen on the paper and zero the machine and then issue a G01 X2.0 command, I expected the machine to move 2.0 inches on the X axis.
It didn't. It moved 0.8142 inches.
To make matters worse, if I now press "Go To Zero" the X axis moves but ends up at -0.2576 in the RDO.

I stuffed up somewhere. Can any one help?

4

Mach4 General Discussion / Mach 4 / PMDX-422 Setup for Dummies

« on: February 27, 2015, 12:07:59 AM »

Hi Folks,

First time poster, newbie CNCer here.
I've finished building my CNC router. I've had a great time building it. Its a simple 3 axis stepper for wood only.
It has limit switches on all axis, no home switches and a spindle speed controller.
Motion controller is the new PMDX-422. I've installed MACH 4 and the SmartBob plugin. All is well.

My question. How do I configure MACH 4 correctly?
Everything I come across is about MACH 3, especially the videos.
I know there is a Mach 4 config guide. I've read it about 5 times now, but for someone on a steep learning curve it's like trying to read Klingon.

Is there a "MACH 4 Setup for Dummies" guide I can't find.

All/any help gratefully received.

Thanks
Neil.