Page 1 of 2
Cobalt is up and printing
Posted: Wed Aug 06, 2014 6:07 pm
by Tetsuwan Penguin
Cobalt is the name I gave to the 3D printer I am designing and building. I just got it working and I'm testing him out now. I already printed a few Lego blocks. Now I need to build an openscad model for an

figure!
Posted: Thu Aug 07, 2014 1:52 am
by diehard67
if you make an astro boy model I want a copy of the file.
Posted: Thu Aug 07, 2014 5:22 pm
by jeffbert
Do they work with LEGO bricks from the store? I mean, are they durable? What material did you use?
Posted: Fri Aug 08, 2014 2:53 am
by Tetsuwan Penguin
Haven't tested with real Lego's cause I don't have any. Real Lego's are made of ABS plastic, I'm using PLA . Now I have a problem with the hot end nozzle clogging up, I have a better one on order. Will also have to do a redesign and rebuild of the moving head carriage, as I've also discovered a vibration problem. Trial and error engineering is fun.
Posted: Fri Aug 08, 2014 3:14 pm
by jeffbert
How well do they work with each other? What is PLA?
Posted: Sat Aug 09, 2014 3:21 pm
by Tetsuwan Penguin
ABS (Acrylonitrile butadiene styrene) is a very common petro-plastic used in models and toys. It is not biodegradable, and is made from non-renewable materials. PLA (Poly(lactic acid) or polylactide) is a bio plastic that is long term biodegradable made from renewable materials.
PLA has a lower melting point than ABS, so it can't be used in heat sensitive applications (like left inside a closed automobile in the sun). It is also more brittle than ABS, though the two kinds of plastic have about the same strength. ABS fails more gradually however. For most applications the two are interchangeable.
3D printers can use other types of material as well. Nylon family plastics are now becoming popular.
Posted: Sat Aug 09, 2014 5:42 pm
by jeffbert

Years ago, I was hoping to make parts of my own color choice, so I used latex mold builder, but never actually went beyond the molding stage because it was not holding its shape.

So, what colors can you make, & how much per average piece? I wanted to build my own Proteus so I could make a particular scene from FANTASTIC VOYAGE, but the transparent pieces I had were tinted the wrong color. Also wanted to make a NAUTILUS, but also, a wrong color.

Posted: Sat Aug 09, 2014 6:16 pm
by Tetsuwan Penguin
Go Google for 3D filament suppliers, or look on ebay. The stuff comes in almost every color you can think of, and if you print in 'natural' or 'White' you can always paint it with the same type of paints you'd use on plastic models (acrylic type paints should work well). You'd need to learn some kind of CAD program to design you own models to print, things like Google Sketchup, Autocad, Blender, FreeCad, OpenScad all can do the job, and there are others. I think the new photoshop even does 3D. I can see creating stuff for model railroading on the 3D printer.
Right now my hotend-nozzle has started to clog up in the middle of a print. It was a cheap kit off ebay, I've ordered a better one (at twice the price!) from a place in Australia. Hopefully it will get here next week.
Posted: Sat Aug 09, 2014 8:11 pm
by jeffbert

Thanks, Tetsuwan Penguin!
Posted: Sat Aug 09, 2014 8:36 pm
by Tetsuwan Penguin
Oh BTW, the cost of most of the stuff is between $25-$50 per lb (2.2kg) spools. A lb of plastic goes a long way.