Suggestions to Harden Plastic Enclosure

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appleman6161   1 mW

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Suggestions to Harden Plastic Enclosure

Post by appleman6161 » Sep 17 2017 5:44pm

I am using a modified tupperware container to house my electronics. Photos here for reference: https://www.flickr.com/photos/bensacks/ ... 6673787494

The plastic tupperware has cracked on one corner and side. I am considering options to reinforce it. Beyond typical epoxy in the cracks, can anyone suggest a method to harden the entire enclosure? I am thinking of an epoxy type coating I can cover the entire piece in or perhaps some sort of carbon fiber or thin material that can be flexibly applied before it hardens.

Any tips appreciated. Thanks!

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Icewrench   10 kW

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Re: Suggestions to Harden Plastic Enclosure

Post by Icewrench » Sep 17 2017 6:46pm

Sounds like a job for fiberglass cloth with epoxy resin.

Good luck

Have fun.

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spinningmagnets   100 GW

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Re: Suggestions to Harden Plastic Enclosure

Post by spinningmagnets » Sep 17 2017 7:51pm

I agree on fiberglass. Buy a bass-boat hull patch-kit. That will have a full list of the right amount of components to pull off this job as cheaply as possible.

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Dauntless   100 GW

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Re: Suggestions to Harden Plastic Enclosure

Post by Dauntless » Sep 17 2017 10:07pm

The polyester resin used for fiberglas is good, you don't actually need the fiberglas itself though it will make it stronger. But tupperware itself doesn't allow things to adhere well. Epoxy will work better than polyester or vinylester, but I don't think it's the answer. If you try it I suggest putting it on the inside rather than the outside.

What is determined to stick to ANYTHING? Urethane. Gorilla glue, for example.

But my real advice is to look beyond tupperware. I don't think you'll come up with anything that lasts.

You might try using the tupperware shape as a mold master to create a new casing. https://www.smooth-on.com/ A process similar to this would probably give you what you want. https://www.smooth-on.com/tutorials/2-p ... n-example/
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Izits   100 W

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Re: Suggestions to Harden Plastic Enclosure

Post by Izits » Sep 17 2017 10:14pm

What about 3D printing a custom enclosure out of ABS?
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appleman6161   1 mW

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Re: Suggestions to Harden Plastic Enclosure

Post by appleman6161 » Sep 17 2017 11:41pm

Is a kit like this what is being referred to? https://www.amazon.com/3M-420-Fiberglas ... B000BO9NOO

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Re: Suggestions to Harden Plastic Enclosure

Post by Dauntless » Sep 18 2017 12:30am

I'm sure it's what they mean, if only the laminate wouldn't delaminate.

You'll have better luck with:

http://www.westsystem.com/specialty-epo ... ned-epoxy/

http://www.easycomposites.co.uk/#!/resi ... resin.html
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amberwolf   100 GW

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Re: Suggestions to Harden Plastic Enclosure

Post by amberwolf » Sep 18 2017 1:02am

If it's actually tupperware (or one of the many clones), there are no adhesives that will bond to it, as it is probably made of HDPE (you can verify this by looking up the recycling number in the triangle on the bottom of the container). The only method of repair of it's actual plastic is to melt it back together. Too high a temperature will make it more fragile, so a soldering iron or similar isn't recommended.


You can, however, use the tupperware as a mold for the fiberglass/cloth replacement.

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Re: Suggestions to Harden Plastic Enclosure

Post by Voltron » Sep 18 2017 8:56am

Storage containers UV out and get brittle so the trick is keeping sunlight off of them. I would try some of the flex seal spray... They sell it under different names at Home Depot etc. It's like spray on rubber and is insanely sticky.

Whatever you do though with sealed enclosures, made sure it's not letting water in where the wires go, and then trapping it in there.

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Re: Suggestions to Harden Plastic Enclosure

Post by wineboyrider » Sep 18 2017 10:12am

Thinking if it's tupperware maybe JB Weld might work, but it comes in small tubes?
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Re: Suggestions to Harden Plastic Enclosure

Post by amberwolf » Sep 18 2017 3:19pm

As I noted above, it won't bond with the plastic (it's probably HDPE), though it may appear to stick to it at first (many things do, but they all come off once cured).

This page has some info on how one might be able to bond stuff to it with industrial adhesives, but it doesn't seem worth it for this purpose.

http://www.permabond.com/2015/03/31/pre ... yethylene/

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Re: Suggestions to Harden Plastic Enclosure

Post by psychotiller » Sep 19 2017 1:33pm

Ever heard of ABS? hahaha

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Re: Suggestions to Harden Plastic Enclosure

Post by Dauntless » Sep 19 2017 9:58pm

So, dang, you're making those yourself? Printed, injection mold, rotocast, what? Which one seems like his size?
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