the Best glue for m...
 

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the Best glue for metal to plastic is....?

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 ton
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looking to glue a metal bracket to some plastic.
any glue idea's greatly appreciated.


 
Posted : 21/03/2023 6:35 pm
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Think it depends on what kind of plastic. One size doesn't fit all.  Those double sided 3m pads are generally quite reliable though.


 
Posted : 21/03/2023 6:55 pm
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Some plastics like polyethylene, some polyamides (nylons) and acetals are near impossible to glue to anything - joining is usually welding or some form of mechanical joint or fixing. 3M do lots of different types of adhesives and tapes for specialist applications.


 
Posted : 21/03/2023 7:01 pm
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Hot melt 😉 Facebook has taught us you can join anything with hot melt glue sticks and ramen


 
Posted : 21/03/2023 7:12 pm
dyna-ti reacted
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It defo depends on the plastic. But super glue combined with bicarb can be pretty epic.


 
Posted : 21/03/2023 7:30 pm
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Also depends on the application. Something flexible like ct1 might be a good candidate depending on the plastic and if it's a good lap joint.

Edit: not that ct1 is a glue but a adhesive.


 
Posted : 21/03/2023 7:36 pm
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Usually super glue or epoxy. A couple of small screws or wiring it on first often help with epoxy. If you can try on a little bit first. Some plastics won't stick with epoxy, some not with super glue and some to neither. Aluminium and steel can also stick a bit differently too.
Sorry for the non answer. Loctite used to have a nice table showing what glue for what.
Now seems to be a web based chooser:
https://www.loctiteproducts.com/en/productadvisor.html#/step-1


 
Posted : 21/03/2023 7:46 pm
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Edit: not that ct1 is a glue but a adhesive.

To be fair nothing mentioned so far has been glue.

I do have some glue, infact that sticks to everything.


 
Posted : 21/03/2023 7:49 pm
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My go to glue these days is PU glue (gorilla). I have had remarkable success with it. I was gobsmacked how effective it is at gluing aluminium to aluminium.

I have no idea how effective it is at gluing metal to plastic but I reckon that it is well worth a try, especially if you have some knocking around. Clamp it tightly though.

And PU glue is without doubt the messiest glue to use - guaranteed to ruin your clothing, and other stuff, if you don't treat it with the utmost respect.


 
Posted : 21/03/2023 8:45 pm
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We occasionally have to glue rubber and metal at work with black Loctite (480, I think). Might be worth considering.


 
Posted : 21/03/2023 8:57 pm
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If you let us know the metal and the plastic I can take a look and offer advice.

What other properties are you looking for? Is the gap between them small or large? Is it going to be loaded, static or dynamic? Is it inside or outside? Is it likely to fluctuate in temperature, be exposed to UV, or moisture?

As suggested by others some plastics are a pain. Equally some metals are. If you are bonding PMMA or PC to aluminium though it is straightforward.

You'll need to pick something that will work with the hardest substrate, probably the plastic. My guess if you need any sort of performance out of it and you expect it to carry any load you'll need an epoxy or MMA. Tapes would be an option but not my area - I work with (formulating chemist) structural MMAs mostly.


 
Posted : 21/03/2023 9:05 pm
 ton
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it is to glue a metal bracket from a mudguard ( the L shaped one at the fork crown ) onto a wide sks plastic mudguard.


 
Posted : 21/03/2023 9:08 pm
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I recently did this. Pop rivets we're my fixing of choice. Failing that a couple of short bolts. Might even get away with cable ties. I'm not sure that there is a glue that can take all the shaking and waggling of a mudguard. Mechanical fixings likely to last longest. I think that the factory fitted brackets are often riveted on.


 
Posted : 21/03/2023 9:18 pm
 ton
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i was unsure. short flat head bolts maybe. cheers all.


 
Posted : 21/03/2023 9:26 pm
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Sounds good ton. Bit of threadlock or nylock nuts probably worthwhile to prevent them shaking loose.


 
Posted : 21/03/2023 9:31 pm
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SKS ‘chromaplastic’ mudguards are made from CAB (cellulose acetate butyrate) - plastic most commonly used to make clear blister packaging. It can be bonded using methyl methacrylate adhesives - so you could try this:

https://www.easycomposites.co.uk/vm100-black-methyl-methacrylate-adhesive


 
Posted : 21/03/2023 10:03 pm
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Not a clue ......soz


 
Posted : 21/03/2023 10:35 pm
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Everbuild Stixall is pretty epic. Use it a lot at work for all kinds of applications.


 
Posted : 22/03/2023 5:38 am
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I love threads like this, not least as I want to glue/rivet an extension to my mud hugger.
Someone on here knows everything about something, it’s ace.


 
Posted : 22/03/2023 6:08 am
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If Dovebiker is right on the plastic then MMA types will work. I did something similar using SG5000 one of the products I work with. My choice was largely based on a broken mudguard at work and a couple of kilos of glue I wanted to bin anyway! We fatigue test so the right glue would be ok.

In the past I've put a thin bit of aluminium under the guard, drilled and bolted through to the L plate when rivets have corroded. Might be good as a belt and braces approach. I've also used sugru because I had some. Specialist glue is expensive and I would often use what I have to hand.

Usual common sense stuff but roughen the surfaces and make sure they are free of dirt, dust and grease. Improves your adhesion.


 
Posted : 22/03/2023 7:00 am
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I attached that bracket to a front SKS mudguard. I used the flat reinforcing plate and small nuts and bolts normally used to attach the spring clip to the rear lower muguard bridge.


 
Posted : 22/03/2023 7:15 am
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I wouldn't be glueing the front mudguard. If it does come apart, it might end badly if it gets trapped in the front wheel.

You could bolt it up using a dome/hex head to avoid it sticking out too far inside the mudguard. Sometimes the rear guard is bolted directly to the underside of the brake bridge in a similar way. I'd do that.


 
Posted : 23/03/2023 12:50 pm

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