Broken thermistor and other troubles
- Details
- Published on Monday, 25 February 2013 10:05
- Written by Alex Davies
So the first problem of the evening, my flatmate accidentally snapped the termistor on the heated bed of our 3D printer. I thought I could just measure the temperature manually, but it turns out the printer won't power the bed at all unless it's getting a value for that thermistor. Not having any appropriate resistors on hand and not having the time to dig through the firmware, we had to improvise. The solution was something called a liquid rheostat. Basically, you put both leads in water and slowly add salt. The more salt you add the lower the resistance. That gave us a fake resistance value and fixed the bed.
Someone also put the bed on backwards. That was a lot easier to figure out.
The Deconstruction
- Details
- Published on Saturday, 16 February 2013 04:29
- Written by Alex Davies
In the interest of forcing myself to be productive, Tristan and I have decided to take part in an event called the deconstruction. Well I'm presuming Tristan isn't doing it to force me to be more productive, but you never know...
In the interest of that, we pulled the CSS from Traverse's website, brightcrow.ca. It's a nice little web design company.
We're using Tristan's paper mache cello project as our entry, only downscaled to violin size. It actually sounds pretty good, or it would if Tristan knew how to play. It sounds like a cello, is the point. A big motivator for us taking part is that we want to do workshops, so publicity is good. 100$ will get you your own cello, violin, or guitar. Plus, honestly, it's a lot more pertinent than any of our other projects, and it would be very nice (if unlikely) to win that laser cutter. Some people have been trying to start a local hacker maker space, and I think they could rally around something like that. Right now they're having trouble getting members to donate money or tools, and they're sure as hell not getting their hands on my printer. I think people would pay the ~$30 a month we'd need for rent just to access the laser cutter. I might even consider (probably not) giving them access to my printer, but it's still way too finicky.
Trying very hard to avoid doing any of it in advance. It goes against my nature not to be planning this beforehand. May have to pre-print the form in advance though, it could eat half our time. Hopefully our gt2 belt overhaul comes in by then so we don't have to print with the borked Y pully. If not, we'll probably try to do it with cardboard, and god knows that won't end well.
Openscad DXF extrusion
- Details
- Published on Friday, 08 February 2013 18:21
- Written by Alex Davies
Finally got DXF extrusion working with openscad. Turns out it's actually pretty good at organic shapes, under the right circumstances.
Violin2 is an intersection of a scaled sphere and a rotational extrusion of "violin.dxf". It turned out pretty good.
{gallery}paperviolin{/gallery}
You can see a more in depth post on how I made it as well as download links for the source by clicking the post's title.
Lightbulb Still
- Details
- Published on Tuesday, 01 January 2013 08:24
- Written by Tristan Trim
Hi all.
Me and Alex decided to do some experimenting with a light bulb and some of home brew 20ish percent alcohol. As some of you may or may not know, light bulbs are tempered to withstand quite a high temperature, so we made an alembic!
Basically, we took a light bulb and broke the end away with some pliers and cleaned out the inside. This takes some practice, you can break the bulb in this stage. We also drilled a hole in a cork and bent some copper tube to fit through it. That pretty much finished the alembic, so we hooked up some clamps to mount it on, poured some of our starting solution in the bulb, and lit a tea light under it.
It took a while to get going, and we where trying to avoid letting it get to a full boil so the alcohol would separate from the water. Even so, after forty minutes of nothing happening we just let it go, to see if we could even get anything going through. Soon it was dripping along at a good rate, and what was dripping out smelled very strongly. So our initial findings is that you don't have to be too careful about the temp not getting to high. What came out must have been a pretty high percent, we had no trouble at all getting vapours alight.
If you try any experiments like this, don't forget safety equipment.
