Hi, I am a complete newbie with all things plastics, so please forgive me if I sound stupid. But i figured that you engineers are experts so are the best guys to ask about this kind of thing. what process would be required to make these from old vinyl records? http://sandboxworld.com/wp-content/uploads/2010/08/VINYL-BOWL.jpg If you could help me out I would be really grateful, Thank you very much Chris
Hi Chris. The ones in your pic appear to be made using Thermoforming. Maybe vacuum assisted and with a "positive" mould for extra crispness: e.g. Here's an example of very, very crude version of this process you could try at home:
would you know what specific type of thermoforming? my original assumption was vacuum forming but the person i asked immediately dismissed the idea
Vacuum forming is basically thermoforming with a vacuum. Vacuum forming may or may not have the positive mould to help it form. I think it depends on the geometry of the part. I'm pretty sure that the LPs in your photo are clamped around their circumference then heated up and pressed into a negative mould by a positive mould. That's basically thermoforming, but I'm sure that there are 1001 other names for this process, and plenty of minor process variations on it. The home-made crude version of this process in the video I think is called drape forming.
I just asked a company that does vacuum forming and they said that they couldn't do vinyl records, I do not know why though.
Many years ago, when disco was going out of fashion, drape forming became very popular;-) The drape forming can be improved by compression moulding between two bowls that conform to each other. If you really want to get fancy you could have some moulds made that are the record thickness offset from each other and with a location feature that fits into the centre hole of the record for even forming.
Hi. Can't quite remember the process but do I remember in my younger days they did this on Blue Peter. (Seriously!). Maybe there are available archives somewhere where you can see this. Regards. Jeff Yates