Vacuum forming coil housings.

[MartinB]

I now use a two stage vacuum system. For years I got away with just using a shop vacuum.. You can make up for the lack of high vacuum by getting the plastic hotter but there is a very fine line between too hot and too cold. You can do it but will waste some plastic until you get the correct time an temperature.

Sounds interesting. Can you share some details?

[dfbowers]

Sounds interesting. Can you share some details?

https://sites.google.com/site/dbcoil...-vacuum-tables

[MartinB]

https://sites.google.com/site/dbcoil...-vacuum-tables

Thanks Don,
Great piece of work

[cristiano.sar]

Finally it almost worked!
I added some screws to the frame, to keep the sheet in place while heating.
Also bought an infrared thermometer to ensure a good temperature.
Used 2mm polystyrene because here is difficult to get other thicknesses like (1.5 or 1.6mm).
Formed at about 150 degrees celsius at the center of the plastic.
My only problem is that it seems that I slightly moved the form to one side (not perfectly centered) so one of the sides not formed perfectly but I will fix this next time.
Here is a video and some pictures of the work:

https://youtube.com/shorts/GFSJxs51uoY









From error to success (left to right):


Thanks!

[MartinB]

Finally it almost worked!
I added some screws to the frame, to keep the sheet in place while heating.
Also bought an infrared thermometer to ensure a good temperature.
Used 2mm polystyrene because here is difficult to get other thicknesses like (1.5 or 1.6mm).
Formed at about 150 degrees celsius at the center of the plastic.
My only problem is that it seems that I slightly moved the form to one side (not perfectly centered) so one of the sides not formed perfectly but I will fix this next time.
Here is a video and some pictures of the work:

https://youtube.com/shorts/GFSJxs51uoY

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From error to success (left to right):
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Thanks!

Well done. Try adding two small wooden pegs to the bottom of your former. These should line up with two holes in your vacuum table and will prevent the former from moving.

[cristiano.sar]

Here are some more videos about my vacuum forming process:
Latest formed shell done today: https://www.youtube.com/shorts/U3bLslijPjY
Explanation of the process (in Portuguese):

[dfbowers]

Nice job!
I have alignment tabs on the edges of my former so it goes into the right place everytime.
Along with temperature, I measure the amount of sag in the plastic while heating for consistency.

Inside your tabs.. no need for a wrinkle. It may be too hot if that occurs. Use a piece of wood to stretch and coax the plastic to the center of the tabs. It took me a long time to get it right but I hardly ever have a dud or a wrinkle anymore.
don.