Author Topic: Melting Plastic  (Read 7902 times)

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Offline VegaObscuraTopic starter

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Melting Plastic
« on: June 30, 2009, 07:55:44 AM »
I want to buy/make something within the price range of $30 that will melt down plastic into a liquid form.  That way I can take any plastic I have around the house such as empty water bottles, product packaging, stupid plastic junk I don't want, and broken appliances and throw them in to get a pot/bowl of molten liquid plastic.  Then I would pour it into a cooking pan and let it cool to make it into a square or rectangular sheet.  Then I could cut it into whatever shape I need and put pieces together either with super glue or by melting the edges with a soldering iron (one that will never be used for soldering, of course!).  There are just 2 things I'm worried about.  1 what can I buy that will get hot enough to melt a pot of plastic?  I was thinking of one of these:

http://www.walmart.com/catalog/product.do?product_id=8467244

With a typical metal cooking pot.  Would that be able to melt plastic like I'm hoping?  The second thing I'm worried about is whether or not this would cause harmful fumes.  I don't want to die in 5 years because I enjoyed making my own plastic parts.  Would doing it near an open window be sufficient ventilation to keep it from doing anything harmful?

Offline GearMotion

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Re: Melting Plastic
« Reply #1 on: June 30, 2009, 12:31:08 PM »
The second thing I'm worried about is whether or not this would cause harmful fumes.  I don't want to die in 5 years because I enjoyed making my own plastic parts.  Would doing it near an open window be sufficient ventilation to keep it from doing anything harmful?

I would strongly advise against this. Melting some plastics releases poisonous gasses. Immediate death.

And I doubt it would work as well as you imagine. Melting a wax candle into liquid wax, and allowing it to cool gets you a wax with the same properties both before and after. Not necessarily so with plastics.

Offline jakx12

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Re: Melting Plastic
« Reply #2 on: June 30, 2009, 02:48:26 PM »
If your desperate in making plastic models use polymorph
Need help with an algorithm or a maths related problem? Ill be glad to help :)

Offline madchimp

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Re: Melting Plastic
« Reply #3 on: June 30, 2009, 03:10:49 PM »
Well as gearmotion pointed out some plastics release very toxic fumes when melted. Another problem with your idea not all plastics are the same. Plastic water bottles and plastic milk jugs are very different plastics and are recycled separately. You also have to consider contaminates. Plastic recycling plants have all kinds of really cool equipment for cleaning the plastic and getting any label material and chemicals off of the plastic before melting and even when some label material slips buy the molten plastic is run through screens to remove anything that has a higher melting point. I'm not saying it's impossible to recycle some plastics at home but you need to do your homework and you will need more than a melting pot to do it. Even the idea of just poring it onto a cookie sheet has a flaw. The plastic will start to cool as soon as it hits the cookie sheet creating ripples and weak spots. Plastic molds are usually heated until the plastic is in then they are cooled so a nice uniform piece can be obtained. I know all of this because I have worked in both a plastic recycling plant and a lost core plastic injection plant.
« Last Edit: July 01, 2009, 02:13:51 AM by madchimp »

Offline Razor Concepts

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Re: Melting Plastic
« Reply #4 on: June 30, 2009, 04:32:49 PM »
Shapelock is a cool plastic material, you put it in hot water and you can form it like clay, and when it cools it hardens.

Offline Metal Slug 2

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Re: Melting Plastic
« Reply #5 on: June 30, 2009, 09:54:34 PM »
hmmm, melting plastic in general seems to be a bad idea.  In addition, what you have in mind is saying something like "I have a whole bunch of scrap metals I want to throw in a furnace and smelt together"  the problem is that metals, like plastics have different melting points and they wont melt together properly.  The temperature required to melt one plastic may be the burning point of another.  This guy tried it: http://www.goedjn.com/essays/botplas.html  The results were not satifactory.  Perhaps a good alternative would be to buy your own plastics and easily mold them by building your own vacuum-form machine: http://www.instructables.com/id/Make-a-good%2c-cheap%2c-upgradeable-sheet-plastic-vacu/?ALLSTEPS

Offline matt liao

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Re: Melting Plastic
« Reply #6 on: June 30, 2009, 11:04:35 PM »
I don't think you will succeed, because with price range of $30, it hard to buy this kind of machine.

Offline VegaObscuraTopic starter

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Re: Melting Plastic
« Reply #7 on: July 01, 2009, 07:07:28 AM »
Thanks guys.  I'll drop the idea.

Offline Metal Slug 2

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Re: Melting Plastic
« Reply #8 on: July 01, 2009, 01:32:48 PM »
sorry, didn't mean to post.
« Last Edit: July 01, 2009, 01:34:42 PM by Metal Slug 2 »

 


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