Wednesday 18 September 2019

DIY CNC Machine



So, it's been a long long long few months. Longer than I had hoped but I finally got the opportunity to be sat here right right now typing out this article on my laptop. It's been one of the longer projects I have undertaken to be sure.


Back in May 2019 I found myself with a mixture or spare time, and some spare money; a dangerous combination. So I thought a little about the ideas, wants, projects in the parts of my heart I have been hoping to approach before the day arrives that we can't approach projects anymore, our health, our families, responsibilities, whatever it may be that means you can't, might approach. But it's important to keep on going, keep creating, learning, designing, tools, ideas, things, just make them. What is important on your last day on earth? Is it having a big pile of money beside you? Or is it the knowledge, the experiences, the ideas, the places you have seen, the people you have met, hated loved?


Anyway, I decided to approach the idea of making a cnc machine. This was in May 2019 after departing one relationship, I needed to keep myself occupied, and to have a feeling of self pride again, I set about searching for ideas, and found that there are dozens and dozens of cnc projects out there and they all have their own slant on the idea.

I have been quite into using found materials lately. And I was drawn to one particular cnc design which uses readily available metal conduit pipe as a main material. It also uses a significant amount of 3D printed parts which reduces the reliance upon bought items.

I already had spare Ramps Board, Stepper Drivers and Arduino from previous 3D printer builds, so all I really needed was Nuts & Bolts.

I set about building.

I started out making a multi-function table, to allow me to cut and clamp wood just like the Festool and Kreg MFT tables. I thought the CNC can come afterward.

I quickly bounced from the completed MFT to the CNC without really pausing, I kinda had some good drive and I wasn't stopping.

I bought Conduit Tubing for $10 per 3 Metres and cut it up with a saw. I then went out and bought a pipe cutting tool after realising how stupid it is to hand cut pipe. Nice smooth cuts with a cheap pipe cutter, you won't regret it.

I pumped out the 3D printed parts one after one after one. I knew it was going to take a while, but oh momma does it take a while. I lost drive and motivation on this stage, I thought about giving up, especially when a 6 hour print failed and I had to figure out how to approach it again. I don't think I could go through printing an entire set of CNC machine parts again, I think it was over 200 hours of printing not including breaks, setups, fails, replacements, prep work, slicing. It was by far and away the bulk of the work.



But once I had the Conduit, and 3D printed parts, I found that I wasn't really following any sort of instructions and I was just making and figuring out. It was just frame work afterall. I really really wanted to get moving in anyway possible after the part printing marathon.

Gradually, I started to get a frame going.

Then it was onto attaching belts, bolts, arms, and skateboard bearings. Lots and lots and lots of skateboard bearings.

Stepper motors, wiring, circuitry, arduino programming, all these things went quick and first time. I feel comfortable if that area. I think I have built 6 3D printers from scratch, tons and tons of planes and drones, and well, It just gets easier until you don't even think about it anymore and you can solve errors in a minute.

Once I had it built, I sat back and admired for a while.

But now to test it, and to test it in the safest and least destructive way possible. I wanted not to damage it after all these hours. So, I started with a sharpie pen and pizza box cardboard. Also one hand on the off switch ready in case.
Fortunately, the test drawings went really well; it's quite hard to screw up plotter drawing.

It's great fun to watch.

I thought then, what next, let's level up.

I moved onto cardboard cutting

Then to Vinyl sticker making
Again, it seems to go pretty smoothly, The cutting might only fail if you don't set the Z axis height correctly. Too low and it digs into the vinyl and drags it, too high and the blade misses scoring out areas. You have to build a feel for the correct height.













A project I found useful to me was to design and create some stickers for my campervan to help me make it look on the outside more campervan-like.


I like that my CNC machine has a good cutting area. I have A2 size which is roughly 40cm by 60cm. Bigger than any home Printer.

Moving on I went to Level 3 and that is to start cutting into wood. I had scraps of plywood laying around so instead of buying special Brazilian rosewood, Teak Slabs, or Kiln dried Oak, I used mistake wood to make mistake ideas on.


I got myself a cheapie CNC Spindle and 3D printed a mount for the Aluminium clamp
Then I designed my first Wood cuts, I took it very slow.
Then I felt confident and familiar enough to use the right tools to make something more satisfying.
The good stuff can come later.

I had some leftover wood, and decided to make a quick easy Screen Printing Press.
I can make stencils to allow me to screen print posters and fabrics.

I also made a touch probe to help home the cnc simply.


Where next? Lasers, Plasma cutting, PCB etching.