Suggestions to Harden Plastic Enclosure

Lightweight / Folding / Portable EVs - seats optional
Post Reply
appleman6161
1 mW
1 mW
Posts: 12
Joined: Sep 23, 2015 1:13 pm

Suggestions to Harden Plastic Enclosure

Post by appleman6161 » Sep 17, 2017 5:44 pm

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!

User avatar
Icewrench
10 kW
10 kW
Posts: 883
Joined: Sep 07, 2008 4:54 pm
Location: Seattle Wa USA

Re: Suggestions to Harden Plastic Enclosure

Post by Icewrench » Sep 17, 2017 6:46 pm

Sounds like a job for fiberglass cloth with epoxy resin.

Good luck

Have fun.

User avatar
spinningmagnets
100 GW
100 GW
Posts: 10920
Joined: Dec 21, 2007 10:27 pm
Location: Ft Riley, NE Kansas

Re: Suggestions to Harden Plastic Enclosure

Post by spinningmagnets » Sep 17, 2017 7:51 pm

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.

User avatar
Dauntless
100 GW
100 GW
Posts: 6387
Joined: May 29, 2010 1:49 am
Location: Coordinates: 33°52′48″N 117°55′43″W

Re: Suggestions to Harden Plastic Enclosure

Post by Dauntless » Sep 17, 2017 10:07 pm

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/
Any sufficiently advanced technology is INDISTINGUISHABLE FROM MAGIC!
- Arthur C. Clarke

User avatar
Izits
100 W
100 W
Posts: 152
Joined: Jan 02, 2017 2:01 am
Location: United States of America.

Re: Suggestions to Harden Plastic Enclosure

Post by Izits » Sep 17, 2017 10:14 pm

What about 3D printing a custom enclosure out of ABS?
The only enemy of the electric bicycle community is the government. Think about it. Who bans or restricts your use of electric bikes, other than the government? Smaller Government = More Freedom.

appleman6161
1 mW
1 mW
Posts: 12
Joined: Sep 23, 2015 1:13 pm

Re: Suggestions to Harden Plastic Enclosure

Post by appleman6161 » Sep 17, 2017 11:41 pm

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

User avatar
Dauntless
100 GW
100 GW
Posts: 6387
Joined: May 29, 2010 1:49 am
Location: Coordinates: 33°52′48″N 117°55′43″W

Re: Suggestions to Harden Plastic Enclosure

Post by Dauntless » Sep 18, 2017 12:30 am

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
Any sufficiently advanced technology is INDISTINGUISHABLE FROM MAGIC!
- Arthur C. Clarke

User avatar
amberwolf
100 GW
100 GW
Posts: 25068
Joined: Aug 17, 2009 6:43 am
Location: Phoenix, AZ, USA, Earth, Sol, Local Bubble, Orion Arm, Milky Way, Local Group
Contact:

Re: Suggestions to Harden Plastic Enclosure

Post by amberwolf » Sep 18, 2017 1:02 am

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.

Voltron
100 kW
100 kW
Posts: 1440
Joined: May 02, 2013 4:53 pm
Location: Santa Barbara CA

Re: Suggestions to Harden Plastic Enclosure

Post by Voltron » Sep 18, 2017 8:56 am

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.

User avatar
wineboyrider
100 MW
100 MW
Posts: 2966
Joined: Sep 30, 2009 9:08 am
Location: Tularosa, New Mexico
Contact:

Re: Suggestions to Harden Plastic Enclosure

Post by wineboyrider » Sep 18, 2017 10:12 am

Thinking if it's tupperware maybe JB Weld might work, but it comes in small tubes?
ES IS SAVED! THANK YOU JUSTIN.

User avatar
amberwolf
100 GW
100 GW
Posts: 25068
Joined: Aug 17, 2009 6:43 am
Location: Phoenix, AZ, USA, Earth, Sol, Local Bubble, Orion Arm, Milky Way, Local Group
Contact:

Re: Suggestions to Harden Plastic Enclosure

Post by amberwolf » Sep 18, 2017 3:19 pm

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/

User avatar
psychotiller
100 kW
100 kW
Posts: 1080
Joined: Jan 01, 2014 7:11 pm
Location: Orange County, Ca USA
Contact:

Re: Suggestions to Harden Plastic Enclosure

Post by psychotiller » Sep 19, 2017 1:33 pm

Ever heard of ABS? hahaha

*edit... pls dont - ypedal
www.psychotiller.com

builds:
XT Wheels/Custom Hub & mount on Randal 180's/Drop Throughhttps://endless-sphere.com/forums/viewto ... 35&t=59259
6" Pneumatic Tire Drop Down/Drop Through https://endless-sphere.com/forums/viewto ... 35&t=60449
"Have you ever heard of Plato? Aristotle? Socrates? Morons!"-Vizzini

User avatar
Dauntless
100 GW
100 GW
Posts: 6387
Joined: May 29, 2010 1:49 am
Location: Coordinates: 33°52′48″N 117°55′43″W

Re: Suggestions to Harden Plastic Enclosure

Post by Dauntless » Sep 19, 2017 9:58 pm

So, dang, you're making those yourself? Printed, injection mold, rotocast, what? Which one seems like his size?
Any sufficiently advanced technology is INDISTINGUISHABLE FROM MAGIC!
- Arthur C. Clarke

Post Reply