Doing the Reprap #12 — First extrusion

Last Friday, while Pilvari Pirtolas had his opening here at gallery Titanik, I was sitting in an adjacent room and fiddled with my machine. I had managed to get the extruder to heat up and the thermistor to register in Pronterface — a previous day of troubleshooting revealed that I’d connected the hotend to the wrong two pins of the Gen7 board — and now it was heating up with no problem and only a slightly worrying amount of smoke. Once it was mounted on the Accesible Wade’s extruder I was good to go for extrusion test.

I got some visitors from the opening next door, and it was fun to see some people react with curiosity and others with disinterest to the machine. To the uninitiated it looks mostly like a heap of metal and plastic, so the awesome disruptive power isn’t always readily apparent, so I got to practice my pedagogical skills on young and old, tipsy and wasted alike. Once I realized that all motors had the wrong polarity in relation to the Teacup firmware, I pressed “reverse” instead of “extrude” and lo! there was extrusion and much exaltation all around!

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Doing the RepRap #11 – Frame & motors

I got the frame of the Prusa more or less assembled, even though I still need to make sure that it’s straight and so forth. The motors are mounted and connected to the correct rods or belts, and they are stepping at 1/16 nicely, although the LM8UU bearings don’t seem as smooth as I’d like them to be; I will probably re-assemble the Y-carriage whenever I add the hotbed, seeing as that might be cause for some misalignment and grinding.

Robin from the forums popped by the studio and we compared builds and I got some advice which is always welcome; where to source materials, in what order to assemble specific parts, why patience usually pays off better than a flamethrower, etc.

The long M3×60 screws for the adjustable extruder have proved elusive, so I’ve gone for an M3 rod I’ll put wingnuts on. Once you get warmed up and understand how things are supposed to fit together and what functions they perform, you relax enough to improvise. It’s a good feeling. The Makergear hotend shipped with a mounting plate which doesn’t fit my Accessible Wade’s Extruder so I schlepped the studio bike around looking for 4mm plywood to drill a replacement. Once that’s done and the hotend built, I’m pretty close to testing to print.

Perhaps I’ll be able to melt som plastic into a horrible blob in time for tomorrows opening of the new show here at Titanik and impress Sara who’s coming over for a few days. That would be most excellent.

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Doing the RepRap #10

Before you can print from your STL file you need to convert it to gcode. Think of it as Postscript for 3D-printers and 2D routers. The tool of choice for people working with RepRap has been Skeinforge, which has acquired tons of functionality at the expense of usability: It’s ugly as sin and has more features than are properly documented (or documented at all) so I’m happy to see that there are alternative versions cropping up, like SFACT.

Also, putting the printer together I ran into some issues with the otherwise excellent documentation put together by Gary Hodgeson, namely the parts using the LM8UU linear bearings instead of printed bushings. Because I don’t have any spare parts I’m terrified of messing up those I bought from Greg Frost (shipped all the way from Australia) so am anxiously browsing the RepRap wiki and forums in search of instructions. I’ve already managed to put the Y-motor bracket in every position possible, and finally had to email Greg to get a picture of how to do it properly. I’m documenting every step, but so far it’s more of a blooper reel…

I finally found an excellent description of how to fit all the parts together: How to build up a LM8UU Linear Bearing Prusa. It does exactly what it says on the tin, and with the exception that I’m going for a three bearing bottom plate, I ought to be able to finish the build in no time. Now, if I could only settle on which lubricant to use for the rods, I’d be set. “Light machine oil” or “PTFE spray” is the question.

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Update from the comments. In the video below I’ve inserted the pins from the wrong side. The black plastic bits should go on the underside of the Polo, so that it’ll sit flush with the mounts. As it stands, the Polos work for me soldered this way as well, but it’s more finicky and there’s a risk that you’ll have too much solder left and won’t be able to push the pins far enough into the mounts.

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Doing the RepRap #9 — Ghost exeunt!

So I re-read the Gen7 1.2 instructions, and found there a note that one should solder the male headers onto the Pololus. I had thought that the pins were a tight enough fit not to necessitate soldering, but gave it a go regardless. And what do you know, it bloody worked. Getting this to work has been a major hurdle, and it’s been an ongoing bother the past two months. So yay me, and yay to Traumflug who has been a great help, and yay let’s move on to other problems now. Like for example finding spare parts to the hot end I just broke.

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Turku: Walking and crossing

Perhaps I ought to learn at least some phrases in Finnish. I feel as close to an imperialist as I’ve ever have, asking people “svenska, talar du svenska?” all the time. Case in point: I forgot to bring a carry-around bag so went hunting for one in second hand stores. In one cramped store I find a cloth bag but try to ask the older lady if she possibly has something similar but with longer handles, appropriate for fashionable slinging up on ones shoulder. I go through English and Swedish and pantomime and am bringing out my notebook for some Pictionary, when both she and her co-worker just wave me out of the store, with a “thank you” (unless “kippis” has a second meaning, such as “shove off”) and gesturing that I can take the bag and leave. At least I hope that’s what they meant, but for all I know they thought I was telling them to “put all your money in this bag, make it large money,” and they were thanking me for not hurting them. I don’t know.

I had ambitions when I first got here that I’d use the time to whip my pasty butt into some sort of shape resembling an actual butt, and started out strong with jogging every second day and even going so far as to checking out the dorm gym. A week later I’m feeling a slight cold coming on and I’m drinking beer and eating crisps for dinner. I’m sure there is a middle-ground somewhere, but I’d be fucked if I can find it. I do hope that I’ll keep up the running though, if for no other reason than to balance out the hours sitting in the studio poking at the RepRap.

Speaking of which, I’m having some progress in the building department, and have half of it put together already. It’s probably the most straightforward part of this whole endeavor, and mostly entails following instructions and spinning a lot of bolts onto rods and such, but at least there’s a physical thing I can point to and say: Behold! Yesterday twas but a heap of rods, today it stands on it’s extruded feet. Verily, progress! etc. etc.

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Two more observations regarding the traffic in Turku: First off, the bikers here drive poorly, often on sidewalks or against the flow of other bikes, while at the same time not signaling. This is in large part because the bike lanes are merged with sidewalks more often than motor traffic, and it’s just too crowded with pedestrians to allow smooth going.

Secondly, drivers are much less likely to stop for you at a zebra crossing, even if you’re already halfway in the road. Anecdotal data, and so on, but it’s happened enough times for me to notice. Also, people are very hesitant to walk on red on a crossing, even when it’s safe; It’s possible they know something I don’t. My lack of inhibition in this area makes me feel very low level badass, as pedestrian badassery goes.

Maybe related: back home people get the hell out of the way when there’s an emergency vehicle flashing lights, while on three occasions I’ve seen an ambulance or cop car stuck behind traffic which didn’t budge. Granted, once it was an older driver obviously lost and looking for the right exit, but you’d imagine that the honking, blinking, waving and shouting police behind her was a clear enough signal. So perhaps it’s an indication of an individualistic yet wary mindset? Should one do generalizations of a whole city — nay people —  on the basis of walking back and forth along four streets for a week? Of course one should, what kind of question is that?

Doing the RepRap #8 — Shooting the trouble

Having set up the studio space here in gallery Titanik I’m once again struggling with the electronics of the RepRap. I got the board back from Traumflug — in addition to fixing it he’d also made it shiny! — and he had successfully used it to move motors and such, so the board is OK. But when I plug in my Pololus and motors and PSU, nothing much happens. Frustration runs high with this one. I have two videos of the troubleshooting below:

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In the first video I have a 300W PSU hooked in to the board, and in the second video I try to use a DVD as a load resistor, after recommendation from Traumflug. Spoiler alert: In neither of the videos does the board move the motors, nor give me a reading on the meter. The next step will be to to add a proper load resistor onto the PSU instead of the DVD player— this is slightly more involved than just jamming a bunch of ¼W resistors in there, so I’ll have to do some research on it. The following links might give a clue:

How to Convert a Computer ATX Power Supply to a Lab Power Supply
Desktop power supply from a PC

An alternative to this would be to get a totally new power supply. I know that people have been using Xbox 360 bricks for power, and I’m sure there’s a crapload of alternatives which would work. I’m just hesitant to give up on the only part of the RepRap which I’ve actually scrounged myselft — The PSU was going to be thrown out with a bunch of computer trash at Chalmers, and I thought I’d give it a second chance at usefulness. Not that this project lacks DIY spirit and such, but you catch my drift; Ideally you’d be building the whole printer out of garbage and driftwood.

Turku: upsetting

Besides walking around Turku and trying out vegan cupcakes (yay cupcakes!) I’ve started work on building the RepRap at the gallery. I have all the metal bits cut to proper length, and the threads fit the screws and the printed parts I got from Greg Frost in Australia. Last night I was polishing the threaded rods, after which I realised that I could actually start assembly of the rig. I was too tired to do it yesterday, and I still haven’t decided on how to do with the bottom plate (I’ll forego the heated plate at the moment, it’s easy to drop in once I have it) but after the weekend I’ll have somehthing which actually looks like a RepRap. It will feel good to have a frame on which I could pin my ambitions literally instead of all figuratively, in my head.

Of course, the hot-end from Makergear still needs assembly — and it’s a total PITA to put together, let me tell you — and the electronics are still home to a stubborn ghost, but it’s getting there. Once I’ll relax a bit more perhaps I could actually scout opportunities to do something with the printer which doesn’t revolve around the printer itself…

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Performance bus: Turku

With my arrival date set, I was invited to go along as audience on a Performance Bus™ with a bunch of spectators and performance artists. It seemed an excellent opportunity to see the surroundings of the city as well as meet people, so of course I signed up. Ever since my ask over at Metafilter I’ve been trying to come up with coping strategies for performances, and immersion therapy might be just the thing to push me over the edge into something resembling professional behaviour.

Most of the time, I’m not comfortable enough with the form to have an opinion one way or another, but insofar as I have a taste, it skews toward those performances which don’t take themselves too seriously. A group performing in the bus did so in Finnish, allowing me to fill in the blanks of their text, or rather just focus on the rhythm and rhymes — as a result their performance was one of the more interesting ones. This goes to the heart of what David Sedaris learned from his career as a performance artist:

It was the artist’s duty to find the appropriate objects, and the audience’s job to decipher meaning. If the piece failed to work, it was their fault, not yours.

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Kimmo Modig, the director of Gallery Titanik was along for the ride to do a performance, and we spent the trip chatting about art and related topics, as well as chickpea pancakes. We seem to agree on many things, so he’s obviously a clever and sharp fellow. For his performance, people could help themselves to a bucket with all the money he’d received to do the performance; in the end he tossed the remainder into the river. Value-destroying performances have been done before of course, but I imagine that actually tossing fifty Euro into the drink feels different from thinking about it.

All in all, driving people around from one event to another is a good way to ensure a captivated audience, and it was a day well spend, especially with an excellent picnic at the end of it. You can read a short article in Finnish about it on uudenkaupunginsanomat.fi and in English on Facebook, and I’ll post some reviews as well once I find them. Leena Kela, who is the regional performance artist of Finland Proper (and who organised this Performance Bus, see video) does some other projects of her own which might be interesting to check out. For example, I’m going to read up on the outcome of Alter ego — being someone else for a month, and then having to refer to oneself in third person. “Yes, she was much ruder and ate a lot of cheese.”

First impressions: Turku

I still require parts for the RepRap, so I walked south on the recommendation that K-Rauta might stock the metal rods I need. The surroundings quickly changed into an industrial park, and shortly thereafter I find out that K-Rauta does not have what I need, unless I what I need are two burly men behind a counter. They did point me to an adjacent store which looked promising albeit closed, so I’m going back there Monday.

I’m staying in a student dorm named Domus, and have found a jogging route. The shared kitchen is a dump but there’s Al Jazeera English on the TV and a balcony I’d appreciated were I still smoking. The room is nice enough, fridge kettle shelves, and the smell of soap will be renewed once a week when someone cleans the room. Oh, and there’s a sewing machine in a cupboard, which will come in handy since my last pair of Cheap Monday jeans once again have experienced crotch failure.

The esthetics of the city is odd — it’s a mixture of fifties functionalism and drab Soviet buildings — and wherever there might have been an uncertainty about what to build, they just poured more asphalt; The roads are wide and everywhere. If there’s a city planner, that guy sure likes cars. Given a chance, I’ll ask.

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Doing the RepRap #6 — repair, rebuild, rejoice, despair.

In anticipation of fucking shit up I had ordered two ATMegas and having succeeded once it took me one try to get the bootloader to take this time around. The board looked fine, but after a lot of trial and error, error, and error, I resigned to the fact that my Pololus probably were fried and ordered new ones. And that, kids, is how you literally burn 600 SEK by being a lazy bum and not double-checking your solders. Lesson learned and so on.

Having received the new Pololus, and with an extruder underway from the States and the plastic parts coming over from Australia, I only need to get the motors to spin to have a semblance of a printer up and running. I have most metal parts except for some springs and wingnuts, and to celebrate the birthplace of the machine I got some SKF 608 bearings. Oh, and I still need two T5 timing belts.

In the IRC channel I was suggested to use Pronterface.py instead of ReplicatorG as a computer side controller of the board, but after the first few times I couldn’t get the thing to launch and reverted to ReplicatorG. Not that it matters at the moment, because even with the ATMega replaced and properly bootloaded and running Gen7 Teacup, I can’t get any readings or functions out of it. I made a video of my attempts and you can watch it below; it’s dry but you get to watch me prod an inanimate object with clumsy fingers.

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Mom and Tomasz decided to visit now as well. I’ve shown them the archipelago and then my allotment garden and then the KKV workshop and then mom left and now Tomasz is stuck with me while I whine about the RepRap and hush him while recording troubleshooting videos. You can actually hear him in the video above, so it’s well worth watching for that alone! Also, I totally destroyed him at pingpong earlier today, and have video of that as well.