Status: on pause.

All progress is relative: in this case, it's lateral. On saturday, my printer died; given that I prefer to possess paper printouts of parts and plans (thppppt!), that's an impediment - when you factor in that I needed to reprint a few of the McWire layouts on self-adhesive labels, that became a larger issue. And funding is, as always, a little tight. Fortunately, a combination of store sale and timely coupon combo shaved a hundred off the next generation model of my previous laser printer: the new one is sleek, quiet, and wireless - just sits in the corner of my office and spits out art and schematics without complaint. So far, I'm happy. Come a long way from the StyleWriter II. (That said, I wish I still had my StyleWriter. A nice big stepper motor in those, along with the control electronics.. ;)

Not dead!

Just resting. Had some PC issues, illness, funding failures and various other distractions. Not stopped.. just going slower than I'd hoped, and that'll probably be the case for the next month or so at least.

Still to do, organizing my thoughts:
- Cut replacement X axis c-channel to replace the one I drilled incorrectly
- Mill UHMW plastic to PTFE dimensions and install on XYZ stages
- Consider redrilling and tapping the mounting holes in the floor flange and vertical stage to use 1/2" bolts for strength
- Finish threadlocking and reassembling pipe base of McWire
- Order some solder paste-inna-syringe and experiment with the hotplate to get the reflow station working right.

I really can't exaggerate how handy having a modestly complete metric/imperial tap-and-die set is for mechanical construction. I grew up with a neat Meccano-knockoff set, lots of metal struts with predrilled holes and 10-32 screws and hexnuts to hold it all together. Handy for mockups and quick structure work; but! If you've got a drill, some bits, and a half-decent range of taps and dies.. everything becomes an Meccano set in the making. n.n

Got my control boards in the mail today! Some assembly required.



When I first got into electronics in my teens, I was pretty good with discrete digital and ok with analog, but there were two areas that were just beyond my skillsets - one was working with the miniature SMT stuff, 'surface mount' components which were rapidly becoming all the rage - and the other was microcontroller circuits, which were also the cat's pyjamas. But you needed reflow equipment for the first, which was out of my range, and you needed to learn assembly language for the latter, and I was more eager to make things that worked 'out of the box'.

And here I am, assembling the kit to make SMT boards which will be run by microcontrollers. Funny how life keeps presenting the same lessons to you until you learn them, isn't it...

For scale, that coin is a Canadian penny. These parts are 'big' by SMT standards, btw. Got to start somewhere.. n.n

As I've worked on the bot infrastructure, I've realized that I'm going to need somewhere to put it. Ideally on wheels, so I can roll it out of the way. But given that the bot will have lots of wires and cables leading to discrete control and microprocessor boards, and a pc, moving it will be very time-consuming and complicated.

Or I could just make the whole thing self-contained and mobile, so that there's only one or two external cables - say, power and ethernet - and can move it at whim. Even while it's in use! But that would be madness.

Heh.



The cabinet is 19.5"x19", about 30" tall - should be closer to 33" with the casters installed. The three lower 'drawers' are all 4U in height and 18" wide, able to hold a standard or rackmount PC, ATX power supplies repurposed for general power requirements, etc. I am planning to install modules for all the servo drivers, extruder controllers, endstop sensors and such on rails in one of those bays, like an old-school analog synth patchbay. The top 'drawer' will hold two drawers - one shallow for tooling and parts, one deeper for an LCD monitor, keyboard and mouse.

It's overkill, plain and simple: its 3/4" MDF held together by 36 quick-connect quarter-inch bolts. That said, it's sturdy stuff, and should put up with several years of abuse.

Ok, was productive.

I decided to update the plan sticker, rather than just print it out and mark it up accordingly. So, thicker lines, center-marks on all holes, dimensions for thrus and countersinks, tapping instructions.

Probably should have a Creative Commons mark on it, but I'm not sure of the status of the copyright on the original document. Since this is just personal use, I'm cool. If I distribute, I'll check first.

Since I'm out of transparent 1/4" plexi, I'll have to use half my stock of translucent red 1/4" plexi. I'll still have plenty for the project I bought it for, though.

Mildly annoyed

I'm thinking when I'm done this, I should fork and document a set of McWire instructions that work. That's just the frustration talking, of course.

1. I drilled the countersinks too deep on the Z-stage - because I followed the instructions on the sticker sheet, which are noted as wrong elsewhere in the instructions, but not corrected.
2. The parts list gives 5/16"x3/4" pan-head bolts: you may also require 5/16"x1" pan-heads to fully encompass the thickness of certain parts of the bearing arm assemblies.
3. The bearing arm nuts extend down too far - with a 1/8" PTFE bearing glide in place, the bolts will collide with the arms of the pipe infrastructure on the X-stage. You might want to have a handful of 'jam nuts', which are - not too surprisingly - thinner nuts. Personally, I'm going to part them to size on my lathe, because I'm getting annoyed enough to become a little bloodyminded. I went to some trouble to procure these nuts, and by golly, I'll make they should fit. (cue the lightning and spooky music.... now!)

Anyhow. Yeah, nothing ever works right, but this is revision three of another person's work - it should be smoother than this.

Ah well. Need springs. Spring, as they say, is coming.

For now, I need to rebuild the Z-stage from scratch and dust a few mils off my nuts.

Ok, I'm tossing the opto-endstops - I'll likely try mechanical microswitches instead. Heard enough about troubles with the optoboards, odd given how simple they should be. Also need to make another two bearing arms - but at least the verticals are all cut and rounded now. I've resorted to cutting the acrylic with score-and-snap, the classic way, and rounding the corners on a grinder. Overkill, but it works.

Turns out the vertical base may well need to be made of 1/2" acrylic. The docs are.. more suggestions than anything, really. I can't actually determine if anybody has made one of these from scratch before. Which is sort of cool to be doing it now.