metabiosis » input

hello process links

marloes — Mon, 25 Feb 2008 14:12:14 +0000

Some sites to look at during the workshop:

iteration and recursion in design: http://www.theverymany.net
l-systems: http://www.chriscoyne.com/wordpress
l-systems in architecture: http://www.mh-portfolio.com/L_Systems/lsi.html
fractals in design: http://www.complexification.net/gallery/machines/invaderfractal
particles: http://www.complexification.net/gallery/machines/bubblechamber/index.php
automata: http://www.solaas.com.ar/dreamlines/
alife: http://blog.metaphorical.net/page-plankton
chaos in crafts: http://www.generatorx.no/tag/chaos

semi-rigid urethane even better?

marloes — Sat, 15 Dec 2007 13:10:41 +0000

My little epoxy shop was finally up and running, working like a charm and heading for great success until… well until I ran out of epoxy and went to the shop to find out they DIDN’T ORDER ANY NEW AAAAAAAAAAAAAAAAAAAAH!!! I only produced 1/3 of the total needed amount so had no choice but to look for alternatives… Fast curing alternatives, cause time was running out. I found a semi-rigid urethane that had a few good points and a few bad ones. Good points: with a little accelerator added (so-cure) it cures in a few hours and is de-moldable in 1 hour! It is semi-rigid, so it is super easy to handle. Bad points: it is yellow :( and not as transparent as the epoxy… In the end I think the speed of production won from the yellow and I got myself 2 liters of urethane, some so-cure and a proper release agent. The shop is back in action.

epoxy works better

marloes — Fri, 30 Nov 2007 13:52:21 +0000

After the first disastrous attempt at making a cast, I switched from silicone to epoxy. Epoxy becomes solid very gradually so I would have time to wait until it was semi-solid, then paste it into the mold, push the 2 parts together and let it dry. This way I would not have to pour anything through any holes, and the material would be thick enough to be able to spread it over the mold by hand. The only big disadvantage of epoxy is that it takes AGES to harden completely. I got good advice from the FormX shop in Amsterdam. They told me to use a moderate heat to speed up the process. Epoxy is very heat sensitive and with a temperature of +- 40 degrees Celsius things would go a lot faster.

Indeed! My first attempt went quite well, although it was difficult to get the shape out of the mold without damaging it. I have to take it out before it is completely solid, because then it will be super hard to remove it. The key to the whole process is timing and precision. In my first test it took 2 hours from blending part A and B to putting the mixture in the mold, and another 2,5 hours before I could remove it from the mold. Then another 8 hours before it was completely solid. The second test took much longer, I put the mixture into the mold earlier to see if this would minimize the risk of air bubbles. I also did the test in another space with another heater. All this directly affects the duration and result.

A short step by step of the process:

1. Measure part A
2. Measure part B (1/2 of part A) and mix in white pigment
3. Blend part A+B and put on heater
4. Wait +- 2 hours
5. Grease up the molds with vaseline really carefully (otherwise the epoxy will stick to the mold)
6. Stir the material every now and then
7. Poor or push the paste into the hollow mold
8. Push the convex mold into the hollow one and put some pressure on it to keep them together
9. Wait for 2,5 hour +-
10. Carefully open the mold (with a lot of muscle power)
11. If the material is still too flexible, leave the shape in one part of the mold to harden a bit more
12. Take out the shape and let it rest for +- 8 to 15 hours
13. Fine tune the shape using sandpaper, hammers and a blowtorch :) afterwards, polish the epoxy to let it shine

meshy assembly

marloes — Thu, 29 Nov 2007 14:37:22 +0000

Another mass soldering post, this one less skeptical since the procedure has been drastically optimized and this time 4 beautiful boards saw the light! Once again in the midst of a whirlwind of chaos but resulting in a little garden with 4 shiny noise emitting flowers.

meshy mass soldering

marloes — Thu, 29 Nov 2007 14:04:14 +0000

Today we did a session of meshy mass soldering. The hardware design is final and the honorable job of reproducing it at least 8 times has commenced. Optimized approach will render about 2 boards in one session (the session length is still under debate and so is the optimized approach). This part of the project is very zen but the table on which it all took place bares very little evidence of this.

failed first experiment

marloes — Wed, 28 Nov 2007 13:34:29 +0000

Today I finished the hollow part of the mold. I spent most of the day smoothing both parts of the mold with sandpaper and getting rid of some of the errors the CNC made. Some edges are simply not possible for the machine to make, so I have to manually adjust. It is turning out to be a very craftsy project.

After sanding the mold I was ready to make my first cast. I had never done this before in my life, so it was a brand new experience and one that I will not easily forget. I blended the parts A and B (10:1) and surprise! It became a super sticky and thick paste, impossible to poor into a very small hole leading to a very narrow hollow space inside my mold. I decided it would be best to just poor it in the hollow mold and push the convex one into it. Silicone came gushing out on all sides, it was a total mess *blush*

Failed experiment… had to clean the molds and my workspace and come up with a new plan of attack.

CNC milling pr0n

marloes — Tue, 27 Nov 2007 14:14:51 +0000

It is hard to stop watching the machine while it slowly frees your design from a heavy block of chemical wood. Some CNC milling pr0n:

meshy artist in residence

marloes — Mon, 26 Nov 2007 15:49:13 +0000

It is the 26th of November today, and we are in the 9th week of our artist in residence at the Waag Society. The project is progressing a lot and we are now starting to work on the networking and data exchange part of the project. We are simultaneously working on the cases for the electronics at the fablab. This week, Tom is visiting Amsterdam so we can put our heads together and work out how to finalize the project in the upcoming 3 weeks.

Waag Society posts on meshy here and here

milling a mold for meshy

marloes — Thu, 22 Nov 2007 13:42:46 +0000

Today we started making part 1 of the mold, to cast a case for the Meshy objects. We are using a CNC (Computer Numerical Control) milling machine (BZT pf 1000 c) at the Waag Society to mill out the shape. The machine is amazing, I can’t stop watching it. The material used to mill out the shape is OBO chemical wood, a very dense material that provides durable and high definition molds. The software that controls the machine is Deskproto, a 3D CAM software for rapid prototyping.

creating a 3D model for the casing

marloes — Wed, 21 Nov 2007 15:10:07 +0000

We decided to try out 3D milling for creating a case to house our electronics. The plan is to create a mold and cast 8 to 10 cases using a semi-flexible resin. The work flow would be: 1. create a 3D model of the mold 2. import this 3d model into the software that controls the CNC milling machine 3. mill the mold 4. cast the shapes. The Waag Society is hosting the Fablab from the end of August until the end of November 2007, so we were very lucky!

We had no previous experience with any of the steps mentioned before, but bravely set out to do the task. We started out using Wings3D but soon switched to Blender to model the shape. While learning how Blender was working, we quickly realized this was not the way to go. Blender works very differently from CAD/CAM softwares, which are meant for this type of work. Blender has no “real-world measurements” but measures everything in Blender units. It requires you to work in a low resolution and do a sub-surf modifier later to smooth an object, etc. etc. It is not suitable for this task. Running out of time, we got help from Bas Withagen, who created a 3D model in Rhino3D for us. We are still looking for an open source equivalent for this task. We will proceed with milling the model tomorrow.