Plastic Fun :)

[Fulvio]

Check this out...

https://www.youtube.com/watch?v=VdUkOjIP0Ok

[JeffH]

Looks like fun. Must try that one day.
Now where did I put my shredder and injection machine?

[Fulvio]

Looks like fun. Must try that one day.
Now where did I put my shredder and injection machine?

I watched the shredder video too. Looked simple enough, though you do need a fairly well set up workshop and someone to laser cut the parts.

There was also another guy who took a pretty simple approach to making a pulley he needed for a drive belt. Scissors to shred the milk bottles, and a tin can as the mold, then into the lathe and hack at it till it looked like a wheel. It looked just like a bought one!

[autocoupler]

Thanks for posting; can see a lot of model railway applications. Now to find a way of developing intricate moulds cheaply without going to China, who are way too expensive anyway

[Fulvio]

Thanks for posting; can see a lot of model railway applications. Now to find a way of developing intricate moulds cheaply without going to China, who are way too expensive anyway

A mate of mine who moved from here to silicon valley got himself a CNC machine, and he can cut his own molds.

Though you could do it by hand with a milling machine and a ton of patience.

Or then again, since the temps aren't that high, maybe lost wax? Except plastics aren't that viscous, which is why injection molding is a thing.

[autocoupler]

Though you could do it by hand with a milling machine and a ton of patience.

Exactly. Even with a cheap end mill many things are possible.

[Fulvio]

So, I'm at Linda's and she has this heat press, which she uses to make T-Shirts:



And I thought "Wonder how hot it gets to?"

After some discussion, we tried some HDPE singlet bags @ 140°C. Each of the two test pieces is one bag, with the handles and seam cut off, and folded up.



BoPET choccy bags worked well too (we were just destroying the evidence :angel). The bubbling came from getting too enthusiastic about checking progress early. The second piece, at 32 layers, is smooth and the texture of say a business card or heavy denim. Now we're looking for uses, particularly Numismatic ones. Plastic 2x2's, with BoPET windows, maybe?