# How do you bond brass to plastic?



## toyroy

Does anyone here have any knowledge or experience bonding brass to plastic, especially styrene and similar plastics?

So far, I have tried rubber-based adhesives, which didn't work at all well, and J-B Weld, which worked well, where there was a good-size gap. 

But, now I want to sheath a flat plastic surface with a thin .010" sheet of brass, and have the resulting surface remain flat. Any suggestions?


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## PhilipMarlowe

I'll assume you tried photographers spray mount as part of your rubber based adhesives, but if you haven't it might work, and since it's an aerosol spray it applies easily to flat surfaces.

Another suggestion, bare metal foil has a "brass' color too, and Michaels has a thicker version in brass as well.


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## John P

Superglue. 
Hot Stuff Cyanoacrylate.
I'm guessing the thinnest of the three types.

Make sure everything is aligned, 'cause you'll never pry it apart to try a second time!.


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## scotpens

Duco cement (available at most hardware stores and chain drugstores) will stick just about anything to anything, as long as the material is smooth and non-porous. I wouldn't recommend it for gluing foil or very thin sheet plastic, as it has a thick consistency (about the same as tube model glue) and might make the material lumpy.


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## terryr

Brass is JB Welds weakness. It peels off a lot of the time.
Superglue or contact cement on both pieces and let dry.


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## Just Plain Al

Slow cure epoxy, then hit it with a roller before it sets.


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## toyroy

PhilipMarlowe said:


> I'll assume you tried photographers spray mount as part of your rubber based adhesives, but if you haven't it might work, and since it's an aerosol spray it applies easily to flat surfaces.
> 
> Another suggestion, bare metal foil has a "brass' color too, and Michaels has a thicker version in brass as well.


Thanks for the help. Does the foil you refer to have an adhesive on one side?


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## toyroy

John P said:


> Superglue.
> Hot Stuff Cyanoacrylate.
> I'm guessing the thinnest of the three types.
> 
> Make sure everything is aligned, 'cause you'll never pry it apart to try a second time!.


Thanks, guy. Will the thinner superglues fill a joint through capillary action? 

I'm wondering if I should start with a dot in the middle of the sheet, let it set to fix it in place, then apply more around the edge, to fill the rest of the seam?


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## toyroy

scotpens said:


> Duco cement...will stick just about anything to anything, as long as the material is smooth and non-porous. I wouldn't recommend it for gluing foil or very thin sheet plastic, as it has a thick consistency (about the same as tube model glue) and might make the material lumpy.


Thank you, for the suggestion. I have some of this Duco stuff. My brass is .010" thick, and I fear contact cements would require too thick a layer.


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## toyroy

terryr said:


> Brass is JB Welds weakness. It peels off a lot of the time.
> Superglue or contact cement on both pieces and let dry.


Thanks, for the info. What you say about J-B Weld and brass is interesting, in light of my experience. Were you referring to the regular, or 5 minute type?


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## toyroy

Just Plain Al said:


> Slow cure epoxy, then hit it with a roller before it sets.


Just plain thank you.  Any brand suggestions, for the epoxy?


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## John P

toyroy said:


> Thanks, guy. Will the thinner superglues fill a joint through capillary action?
> 
> I'm wondering if I should start with a dot in the middle of the sheet, let it set to fix it in place, then apply more around the edge, to fill the rest of the seam?


 Hm. I'm gonna say "probably." Best to experiment on some spare material.

And, the above-mentioned Bare Metal Foil does indeed have adhesive backing.


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## toyroy

John P said:


> Hm. I'm gonna say "probably." Best to experiment on some spare material.
> 
> And, the above-mentioned Bare Metal Foil does indeed have adhesive backing.


Thanks again, John.  

Although it's good to know about the foil for other applications, I'm not using brass on this model as a finish. Mainly, I'm experimenting with various design and construction ideas, right now. 

The model I'm working on started out as an all-plastic toy. I can use MEK to chemically weld plastic, and brass allows me to employ my technique of pan soldering on the stove. So, you can see why I am looking for an industrial-strength bonding method, for joining brass to plastic.


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## Just Plain Al

toyroy said:


> Just plain thank you.  Any brand suggestions, for the epoxy?


I know it's heresy but I usually use whichever clear 2-part epoxy is on sale at the local hardware when I run out. Curing time is usually printed on the package, right now I have DURO brand with a 15 minute work time.


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## PhilipMarlowe

toyroy said:


> Thanks for the help. Does the foil you refer to have an adhesive on one side?


Yeah, the advantage of the Michaels brand is the sheets are about twice the size of the bare-metal ones, it doesn't want to curl up like bare metal does, and it's cheaper. The disadvantage is finding a pack not wrinkled or folded if you need big smooth pieces. I used some on a Apollo CSM & LEM last year.

Look on the aisle where they have the faux metal finishes.


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## ilbasso

Duct tape?


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