Happily, Dumpsters Provide Everything

Safe, cheap (or free), recyclable, versatile, durable, machinable... I want to find these qualities in prototyping materials.

As of this writing, sadly, I don't have many materials on my list of possibilities. However, I've had one candidate floating around the back of my brain for a while: polyethylene (PE). When I first started considering plastics for homemade parts, I came across N55. Most of their designs seem to make good use of PE. (For example, the snail shell system. Another -- this floating platform -- specifically uses "low-density" PE.)

Reading more about the plastic, it seemed to have a lot to recommend it: tough, mostly stable (not so much against UV (ie sunlight), but I guess you can apply treatments for that), and environmentally benign. (As far as petroleum-derived plastics go.)
Of course, it also helps that I can acquire it for only the cost of pilfering a recycling bin...

Recently, I've looked into it more, and I came across this page, detailing some experiments in melting and forming HDPE (high-density PE). It doesn't look too difficult! ("What could possibly go wrong?")

Now, I don't know about building a boat at this point (like the above author intends), but I have had robots on the brain, and robots can go underwater...

Looks like I have a fun excuse to do some experimenting!

• TODO: gather PE plastics
• TODO: investigate properties of plastic for submarine use (freshwater for now, but why not investigate saltwater also?)
• TODO: plastic forming -- methods, heats, tools, etc
• TODO: safety -- fumes? chemical reactions?

• IDEA: plastic boats
• IDEA: plastic submarines?
• IDEA: robotic plastic boats & submarines?

I'll update this entry as I progress.

If you have any helpful tips or information, get in touch!