I bought a cheap 3D printer. Once I had bought it, I found out it was from clearance but had probably already been in some way paid for, which is annoying. Someone else didn’t get their machine, and while I know there is no direct connection between me having this and another, particular person not having it, I am still profitting in the cheapness of a clearance machine from the money that someone else put in.
That aside, and it’s not a moral problem for me given the circumstances, I’ve now got a cheap 3D printer. The hot end, where the plastic gets melted, is famously terrible on this machine. It was a new design and tiny tolerances were needed, and it didn’t quite work. And also, I broke mine. So I’ve 3D printed a different big of plastic to hold a different head, and someone who was not using an old heater end and some other bits donated them, meaning I’m still getting a cheap 3D printer rather than an expensive time sink. It’s a cheap time sink instead. Currently bits of the hot end are cable tied together and the whole thing is about as shonky as a unicycle on a rocking chair.
Today I bought a new HDMI screen and connected everything up. I now have a working Rasbian computer with wireless mouse and keyboard. I’m well chuffed.
I’d like to do a lot more on it, like wire in the USB sockets on the top of the case, which isn’t horribly difficult. Right now, though, ZipPi is a functional, dedicated computer. It may be a Raspberry Pi 3 soon.
I need to look up the relative prices of linear rail and V-Slot profile. Buying profile might be cheaper, despite having the T-slot already. If it is, I can still use some of what I’ve got, but things like the V slot C beam would solve a lot of my problems.
I’m going to have to keep a whole lot of wiring out of the way. I’ll also want to convert this to be able to take manual input. AND PEOPLE WILL NOT STOP TALKING TO ME WHILE I TRY TO THINK.
I have just been given a lot of aluminium profile. I want to make a cnc router to allow me to engrave acrylic sheets and cut lino. The lino cutting will be the easiest problem, as it just needs a 2d movement and some human setting of the x axis. Plus a lot of glue.
So, the first thing I need to know is how the heck to build it. I don’t want to move a plate under a fixed head, if I can help it, as that makes the entire base way too big, and I don’t want to take up too much space. If I wanted to engrave an area a x b I’d need twice the run, 2a x 2b, to go from left to right. Given I might create big stuff, it’s too large for storage, and too clumsy, and I don’t want to move the platen. I think it’s called a platten. I don’t know how to spell that, so I’ve tried both ways.
So, I’m going to have to move the head, which means linear bearings and stepper motors. And stepper drivers. There should be plenty of explanations out on the internet, and I just need to find an explanation that isn’t geared to solutions I’m not using.
On the internet.
I nabbed some more apple wood from the same tree/friend combo, and this time I used a Stanley knife to pare it down, which was much easier than the pocket knife, both in sharpness and in the shape of the handle. I went through the same process as before, but this time I formed the far end before I started sanding down the wood closer to the join, to make sure it stayed strong there. I also sanded the brass with the fine soft pad, and then I squeezed hot glue into the brass fitting. Then the ferrule wouldn’t fit, and I had to bang it in with a hammer, which meant I had to scurry for a hammer. However, nothing broke, and now I have a pen. It’s a snug fit for pen nibs, but I’m OK with that. I’ve bent the inner springs a little bit to help the fit, and it’s all good, and I have no problems. I’m pondering making a two part top, with bits that fit inside each other, so I can get rid of the need for steel. That’s a long way away, though.
I’ve given it a coat of varnish, and I’ll give it a couple more. That’s to protect it against the horrible mess inside my pencil case, mostly. I’ll also make sure the join ends up full of varnish, so no moisture penetrates.
I nabbed a bit of apple wood from a friend. It’s soft, but that means it works easily, and I don’t have real wood-working tools, so I’m in favour of ease. I cut it to length, skimmed it down with my pocket knife to take the bark off, and drilled into the top to put the handle in, which I did with hot glue. (In case of failure. As it turned out, I was prescient.) I then carved it down further so it was almost the right size to hold, then I sanded it. I did that with a soft pre-bought sanding block, so the handle could sink in a bit. First of all I taped some rough paper over it, and clamped up the block. Then I put the metal into my drill, and went ‘vrooom’. I used the 120-ish grit to tear off most of the surface, then switched to the less brutal surface, and smoothed it. However, after I thought I was finished, I noticed my knife had left a splinter inside an otherwise innocuous dent, so I put it back in, pressed too hard, and shattered the shaft at the bottom. Pants.
I have acces to more apple wood, and I can use that. If it fails again, I’ll have to use something much harder. A friend offered me some rose wood and some lilac, and I could try either of those.
After making the aluminium pen, I showed off pictures of it and ended up agreeing to make a couple more. I did one more in aluminium, and then turned to brass. If it were solid metal, a brass pen would be too heavy, but I can make it out of brass and wood easily enough.
I had a scrap bit of brass, and there was a failed thread already in there, so I took that off very very slowly, and as a consequence my chip size was tiny. It picked up a bit once I had a smooth cylinder. I had had to hold the aluminium at both ends, and the brass was a lot shorter, so although I was using the tail stock for some of the time, it wasn’t in the way, and I only needed to cut a section of it. There was very little chatter. I cut the shoulder slightly wrong, and it has a small step on it, but I’ll see how that goes. It may not need re-doing. I also added rings to the part that will sit inside the handle, to help with the attachment process, whatever that will be. Drilling out the inner part was not difficult, but a combination of lube and chip size meant I could not see what I was doing if I took the drill bit out, so instead of peck drilling, I checked my speed calculations and then pushed harder. Still alive.
We didn’t have a decent parting tool, and my brain was starting to complain about all the work I had done, so I cleared up on the lathe and took the part off the parent rod with a hack-saw. I’m glad I did, because it felt so different to aluminium. It’s really slippery, but it cut well anyhow.
I need to source some wood, make it into an approximate round, and then put it onto the brass part. Then I’ll sand the heck out of it until it’s properly round and fits the handle perfectly. A bit of hot glue, and I’m done. Then I declare tea and victory.
I set out to make a simple dip pen. The ferrules are relatively cheap, and I don’t like the way wooden pens soak up ink and water, and split. Plastic feels wrong, and it’s too light.
I found a bit of aluminium rod that was about the right length, and squared off both ends in the mill. I used the lathe to bring it down to a comfy width, as well as put a shine on it. Because the rod was short, I had to reverse it, so there was going to be a shoulder. I made a feature out of that by notching where they met instead of trying to match exactly. I added a couple of other decorative notches as well.
The ferrule sits in a 1/4″ drilled hole, and I did that in the lathe as well, with a rather battered bit. It had been ground down to chip brass better, I think. However, it worked pretty well. Then I glued it in with araldite. It occurred to me afterwards that I should have used hot glue, because when the ferrule, which is steel, rusts, I’m going to want to get it out of there. Hot glue sounds ideal for something where metal would be involved, and the coefficient of expansion isn’t a problem in removal because the steel sheet is so thin. Whatever material it’s in, it should come out with a bit of force.
I need to move things around in my room until I can find my big bottle of black ink. The only alternative is to declare carpet bankruptcy, build a new floor over the top, and buy another one of everything I miss.
Maybe I could give tidying up a name, and then it would be a project, and at least I would start it.