Awesome DIY Plastic Vacuum Forming - Possible DIY Applications

[Amphiprion]

I found these videos on Youtube:

http://www.youtube.com/watch?v=e5CGfoxnKaQ&feature=channel

http://www.youtube.com/watch?v=yhajk_IDTUo&feature=related

There are several other videos like this, but I thought some of our more advanced builders out there might be interested in this technique for making molds for speakers, acoustic devices, horns, diffusors, or anything with an odd shape you want to replicate. All it takes is a shop vac and your kitchen oven.

Also, with a little larger setup and some sort of large oven, you could even make a DIY Hans Solo in Carbonite for the theater room

[Biermann]

I found these videos on Youtube:

http://www.youtube.com/watch?v=e5CGfoxnKaQ&feature=channel

http://www.youtube.com/watch?v=yhajk_IDTUo&feature=related

There are several other videos like this, but I thought some of our more advanced builders out there might be interested in this technique for making molds for speakers, acoustic devices, horns, diffusors, or anything with an odd shape you want to replicate. All it takes is a shop vac and your kitchen oven.

Also, with a little larger setup and some sort of large oven, you could even make a DIY Hans Solo in Carbonite for the theater room

A decent vid, but as you can clearly see it did not achieve proper form. Rather make a real vac former.

[Hdale85]

Well there are plenty of ways to improve on his design, I see potential leaks all over and I'm not sure he really heated the plastic up enough.

[Deward Hastings]

People have been drape molding acrylic sheet for motorcycle fairings and aircraft canopies for a long time . . . and it should work for any thermoplastic. The key hangups are usually producing the plug mold in the first place, and stretching (thinning) of the material over compound or sharp curves (like a horn). But thermoplastics also tend to weld easily (even Harbor Freight has a hot-air plastic welding kit), so it shouldn't be too hard to rough out a shape and then finish it over the mold.

It might be harder (for horns especially) deciding what shape you want in the first place . . .

[Amphiprion]

Yeah, I think in the first video it was the first time the guy had ever done it. The second video looked like someone who did it more often but could still be improved upon. In any case, I had never heard of this before and we've got so many people working on waveguide projects, custom complex enclosures, etc I thought I would post this just in case anyone could use it. Or if anyone had the guts to do the Han Solo thing

ETA: Actually I now that I think of it I have seen this technique on the TV show "How It's Made" in an episode on how bath tubs are made. They did the same thing then reinforced the back of the plastic shell with fiberglass and viola - super strong perfectly moulded bath tub. I just never knew you could do make a rig to do it at home.

[benchtester]

Takes me back.. In the sixty's, I had the Vac-u-form toy by Mattel. It worked just as good if not better.



Of course, it's not as big.

BTW: some plastics like polycarbonate should be baked at a low temperature to dry the moisture out of the plastic before going to the forming process. Also, I think a female (concave) form would give a crisper surface texture.

Some shapes don't need a mold. Airplane canopies and parabolic dishes can be formed with just a profile frame on top of the vacuum box. The pull (vacuum flow) is stopped when the desired depth is reached.

[penngray]

Cool video...Interesting. seems like a ton of work vs using other methods.

Im using Smooth-on products. Rebound 25, etc to create a mold of my horns, baffle, etc.

www.smooth-on.com does all that stuff with easy videos and their products reproduce the exact duplicate. His video showed it missed some of the details.


I have pics coming of my silicon mold. Im just finish the hard shell.

THe progress is here. Pics of the prototype top section is all that is there the molding will be added soon.

http://www.avsforum.com/avs-vb/showthread.php?t=1255828&highlight=not802d

[Deward Hastings]

Sculpey is also quite useful for prototyping, and making molds. In fact you could probably make a complete horn out of the stuff, especially if you layered in some woven glass for reinforcement, especially around the driver flange.

A scaled-up MakerBot, built, perhaps, around a CNC router platform, might be another option for building horns, or novel enclosure shapes . . .

[nikbrewer]

A guy used to make back for me for car our speakers and it worked well, but he had a pretty nice home built vacume table set up