Homemade, cheap, plasma CNC

SO, managed to have a few wins of recent days.

Finally upgraded to LinuxCNC 2.8.2, still having some issue with not getting an arc, but think that's my tool set not being right yet.

Also managed to get SheetCam to finally load on the cnc computer, so that should make life a little easier.

Still working on my tool set as a modified version of the hypertherm 45 to suit the UNIMIG Cut 45 and the speed of my machine.

Will also try and figure out how to set a button in the AXIS gui to turn my laser (used for alignment) on and off. I have already worked out a ZERO button, Zero button with laser offset, GO TO ZERO button.

And im currently trying to set a tool in sheetcam so i can centre mark with the plasma. Not being the brightest spark, i know that i need to set up a file for it and link what i want it to do there. I just don't know how to do this, so i'm reading but not really making sense of what i read, yet.

Hey Tommylight, upgraded to 2.8.2 and am still having a few arc lost at the start of a cut. Hoping its just a friendly reminder for me to change tips.

Cheers

thanks Phillc54,

I have read this (doesn't mean I understand it).

I'll try tomorrow, knowing I need to adjust the Hal file, not knowing where to reference it to.

Cheer

Hi.  RNJFAB was wondering about your Z axis assembly.  I can see from the build thread you started out with some kind of drawslide setup and then seem to have moved to an openbuild based setup?  One of their linear motion kits?

I'm trying to decide on my own Z design so was wondering what your experiences were, where you ended up and why.

Cheers - James.
 

Hey James,
Z axis has been an adventure.
First problem was I got x axis linear rails too short so can only have a 90mm wide z axis to keep the 1200mm travel I was chasing on the x axis. Tip for new players, get longer linear rails than you need, remember to add the width of the carriage plus your travel wanted plus a little extra.

So the first z axis was a set of linear rails but because I could only go 90mm wide, I needed to put the ball screw and motor above the rails, hence the ridiculous height. then I used an old set of dual action draw slides to create the floating head I wanted to probe off the job. this worked well and was definitely better than not having a floating head.

Then I tried to make it better when I did the x axis gantry upgrade. Bought a z axis off Ali for way more than it's actually worth. its actually shit if I'm being honest. it just runs on some v wheels inside the extrusion, this has more play than the old draw slides I was using. then to get the floating head I had a small linear rail to allow the head to float. it's very average, but it works, and I haven't had a chance to make it better..... .yet.

Planning on upgrading it with some 12mm linear rails and redo the floating head once I get a machine torch for the new plasma. I would like to add an air scribe but can't due to the width I made the machine, I am working on a solution, however it will reduce my x axis travel unless I make the plasma head interchangeable so I can swap between them. maybe that could work.
Cheers

Making a Z axis from scratch really sucks! It took me 3 months in my spare time.
If I did it again, maybe I'd use this one. I think thefabricator used this
step-motion.com/collections/floating-lif...oating-and-breakaway
You might need to change out some sensors or add some pulldowns for NPN/PNP reasons.

Gorgeous looking kit Rod.  But at USD706 (NZD 1,005) it probably breaks the hobby budget criteria. For a build to be used for commercial purposes I can easilt see how it would justify itself in saved time.

RNJFAB - I had been thinking about a linear rod style approach. Is 12mm going to be stiff enough?  I had in my mind that you would want 16mm but perhaps I am over baking it?