Best way of glueing plastic together
Discussion
The sunroof on my car has a wind deflector on an arm that popups up when driving
Unfortunately just before the hinge, it's snapped
The other side is fine
A new one is £100, so I'd like to repair if possible - is it likely that any glued joint will hold?
My default for plastic would've been araldite, but if there's something better I'm happy to try.
Unfortunately just before the hinge, it's snapped
The other side is fine
A new one is £100, so I'd like to repair if possible - is it likely that any glued joint will hold?
My default for plastic would've been araldite, but if there's something better I'm happy to try.
Depending what plastic is it, and the load on it, and if you can brace it externally varys the chance of a good repair from zero to 98% but personally by gut feeling is that £100 is a fair price and I would just pay it!
Can you wrap something like some thin metal or cloth around and dope than with the araldite/epoxy?
Can you wrap something like some thin metal or cloth around and dope than with the araldite/epoxy?
Problem with plastics can be getting a glue that will stick to the plastic!
The epoxy & weld suggestion is worth a go if the channel doesn't need to be there as part of how it works.
If you can get hold of any fine metal mesh use a soldering iron to melt it into the plastic, bridging the break, much stronger than just melting the plastic back together.
I use stainless steel mesh that way on some caravan plastic repairs ( front & rear panels & some 'A' frame covers) before filling & painting. Makes for an extremely strong repair.
Whether that will work for yours I don't know. Bear in mind that some plastics just disappear in a puff of smoke if heat is applied!
The epoxy & weld suggestion is worth a go if the channel doesn't need to be there as part of how it works.
If you can get hold of any fine metal mesh use a soldering iron to melt it into the plastic, bridging the break, much stronger than just melting the plastic back together.
I use stainless steel mesh that way on some caravan plastic repairs ( front & rear panels & some 'A' frame covers) before filling & painting. Makes for an extremely strong repair.
Whether that will work for yours I don't know. Bear in mind that some plastics just disappear in a puff of smoke if heat is applied!
Edited by paintman on Saturday 23 July 01:25
I’ve used this on some headlight brackets with success but as suggested I’d probably just buy a new one.
https://www.amazon.co.uk/Q-Bond-QB2-Strong-Adhesiv...
https://www.amazon.co.uk/Q-Bond-QB2-Strong-Adhesiv...
I too have used Qbond on many very brittle looking things that take quite high loads with 100% success.
Basically it is superglue with a powder that you then pour over the wet excess glue.
It is extremely effective, and can even be built up for more thickness/strength & filed to perfect shape afterwards.
The same effect can be achieved with plastic filings & normal superglue, it really is amazing the strength afterwards & it has the added advantage of being quick.
Basically it is superglue with a powder that you then pour over the wet excess glue.
It is extremely effective, and can even be built up for more thickness/strength & filed to perfect shape afterwards.
The same effect can be achieved with plastic filings & normal superglue, it really is amazing the strength afterwards & it has the added advantage of being quick.
Epoxy most probably but as others have said, it will.need more than just glue. Splinting/reinforcement in the channel section if it has one would be my thought, but fine metal mesh melted in with heat sounds interesting too.
I would def have a go at fixing it - if it doesn't work it isn't going to have cost you much, and if it does it will be a v pleasing repair. Good luck.
I would def have a go at fixing it - if it doesn't work it isn't going to have cost you much, and if it does it will be a v pleasing repair. Good luck.
DickyC said:
Dichloromethane. It's a solvent used to bond plastic. The problem might be buying a small quantity.
Likewise Poly methyl methacrylate (PMMA) where a tube of the stuff, and the applicator, is likely going to be around the cost of a new part! Certainly one from a scrapyard. dhutch said:
DickyC said:
Dichloromethane. It's a solvent used to bond plastic. The problem might be buying a small quantity.
Likewise Poly methyl methacrylate (PMMA) where a tube of the stuff, and the applicator, is likely going to be around the cost of a new part! Certainly one from a scrapyard. elanfan said:
Scrappys
It's a panoramic sunroof off a 3-series estate, it's not a common option and when they are broken the sunroofs are usually sold complete. The part is unique to that model.Very frustratingly I replaced the sunroof a couple of months ago and threw the old one away!
InitialDave said:
It looks like it has a hollow section or U channel shape.
Yes, it's hollow and a small spring sits inside it.dhutch said:
Depending what plastic is it, and the load on it, and if you can brace it externally varys the chance of a good repair from zero to 98% but personally by gut feeling is that £100 is a fair price and I would just pay it!
dontlookdown said:
Epoxy most probably but as others have said, it will.need more than just glue. Splinting/reinforcement in the channel section if it has one would be my thought, but fine metal mesh melted in with heat sounds interesting too.
It's a bit tight around it, but I might be able to get something in there, I'm not sure.
It's going to be a glass filled nylon probably, in which case your only reliable joint, is thorough cleaning, flame treatment and then a Methyl Methacrylate designed for low surface energy plastics. And even then it's gonna be touch and go whether it holds or not. Bonding nylon long term is difficult. Find a replacement if you can, if not like someone else said pin it with a metal rod as well.
Jakg said:
It's a panoramic sunroof off a 3-series estate, it's not a common option and when they are broken the sunroofs are usually sold complete. The part is unique to that model.
Very frustratingly I replaced the sunroof a couple of months ago and threw the old one away!
I feel your pain, especially about throwing the old one away. But for £100 the more I think and know about it, the more it's bargain.Very frustratingly I replaced the sunroof a couple of months ago and threw the old one away!
It's a high stress part, thin and slender, taking a surprising amount of load at a good speed. So for one tank of fuel for me it's a no brainer.
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