search

Pwdr / Pwdr-Model-0.1

A powder substrate rapid prototyping machine
131 stars 68 forks source link

Progress #21

Closed MatthiasWM closed 11 years ago

MatthiasWM commented 11 years ago

I did my first print today. The plaster I got was horrible and everything crumpled to dust. But the machine worked just fine! ;-)

http://youtu.be/v4czkelSGHw

Matthias

Pwdr commented 11 years ago

Hey Matthias, thanks for the update! The printer looks to be working pretty fine. Your X-axis is moving faster than the original Pwdr, how did you manage to do that?

On Friday, April 19, 2013 at 02:27 , MatthiasWM wrote:

I did my first print today. The plaster I got was horrible and everything crumpled to dust. But the machine worked just fine! ;-) http://youtu.be/v4czkelSGHw Matthias

— Reply to this email directly or view it on GitHub (https://github.com/Pwdr/Pwdr-Model-0.1/issues/21).

MatthiasWM commented 11 years ago

Well, I have not yet determined the correct amount of binder. The transport speed is directly related to the number of times I have to fire the nozzles. The nozzles need a short break after firing to refill with ink and cool down. But I also put quite a big effort into synchronizing the firing of the nozzles with the stepper transport to get a very smooth operation. A scope is a very helpful tool... .

MatthiasWM commented 11 years ago

OK, after experimenting a bit, I did not get anything to bind correctly. Ink is not a binder to my plaster at all, and my second attempt with alcohol failed, because the alcohol is seeping out of the cartridge and forms drops under the cartridge holder. Those then pick up plaster, creating something like a dull icicle, which destroyz the powder surface. Meh.

Any suggestions on which liquid to use? I will try rice wine and deskilled water probably tonight.

Boreaz commented 11 years ago

Are you used a pure alcohol? I used vodka (40% ethanol) with water 1/1 and didn't have a such problems. But this is not enough to bind the alabaster that I use, the printed part breaks down when I cleaning it with a brush. Now I think to try super hard dental gypsum.

MatthiasWM commented 11 years ago

I used Gin (for the lack of Vodka or other medicinal ointments) 36% alcohol and a few juniper berries.

Pwdr commented 11 years ago

The alcohol does not enhance binding of the plaster, it's purely there for decreasing the viscosity i order to get it printed with the inkjet head. Notice that the level of bonding is controlled with the number of droplets deposited per spot. For commercial 3D plaster powder, we used between 12 and 15 drops per spot.

On Sunday, April 21, 2013 at 14:36 , MatthiasWM wrote:

I used Gin (for the lack of Vodka or other medicinal ointments) 36% alcohol and a few juniper berries.

— Reply to this email directly or view it on GitHub (https://github.com/Pwdr/Pwdr-Model-0.1/issues/21#issuecomment-16722490).