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Here some pics of Adam and Eve. First two sun glasses fully assembled here in Sri Lanka.
All moulds are designed and manufactured by @leebaz at Colombo Design studio. Check them out.
The mould has inserts that create a groove for the lenses. The groove is a bit flat so we have to grind them a bit deeper manually so we need to redo them to produce a proper batch. Otherwise works really fine, we put them on a car dashboard during Sri Lankan lunch time, which is as hot as it gets and they stayed intact.
It’s a bit tricky to line up the hinges and fiddle those micro screws into the frame but can be done.
We are using mainly Polypropylene. That’s what the rice bags are made of here in Sri Lanka and we reuse them and turn them into bags. The off cuts we stuff into the injection which is pretty easy because no need for shredding.
It seems Polypropylene works much better for injection moulding than i.ex. HDPE. HDPE seems to need lots of pressure while PP is much easier to inject, so higher success rate.
Not sure if that is something others also experience.
Best regards from Sri Lanka.
@margeryk for sure we don’t have a sourcing problem!
Those bags could be a good source as they most probably don’t have much coloring or ink or whatever they use to dye plastics so that could be good. If you get a textile industry heat press you can fuse them into thicker sheets or “laminate” other materials.
@anris The lenses pop into a groove, no glue or anything. On the last pic you can see the aluminium inserts that make the groove. The insert are in place of the lenses when we inject the plastic into the mould and are in the frame when we take it out of the mould. Then we pop out the “aluminium lenses”, clean the frame, pop in the real lenses.
If you have not build or have access to a shredder you could go for that clear packaging material that is widely used in many industries to transport goods form A to B (clothing, carpets and whatnot). That is mostly polyproylene and it makes clear objects which is cool. You can just cut it into stripes, feed it into the injections, off you go, no shredding needed.
Cheers from Sri Lanka,
I just found out about Precious Plastic and wanted to use the technology in the US to make sunglasses, then I found this post!
Would you be willing to share your knowledge on this with me so I could get this started in Oregon, USA?
Alternatively, I would even be willing to purchase some of these from you to get the word out here on the US West Coast.
PLEASE contact me @
I really like these. They should sell well, I would think. Excellent work.
Hi all, and you, dear friend, have a very beautiful and beautiful story about your score and its speed. According to you, these are the examples I have mentioned.
The exact speed of the note was more precise
Thank you so much
Survey is a term used to make the facade of the building look. Nowadays, despite the presence of airborne pollutants, smoke and dust, as well as the reduction of the quality of the facade of the building’s stone and becoming cloudy over time, the need for periodic cleaning of the facade of buildings in The metropolis is felt.seoyab
We have a biomass boiler that heats our hot water for the central heating (and washing), and the pellets that are burned arrive in plastic bags. Lots of plastic bags. I am new to Precious Plastics and think that these empty bags must be all over the place. Just another potential resource.
Best wishes from Cumbria, UK.
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