# contact cement



## 07accordEX (Jan 1, 2010)

Hi, I know this is not flashlight related, but the "other" section is for electronics aswell.

But, I am applying this synthetic foam stuff to sheet metal and aluminum foil for my car.

http://www.homedepot.com/h_d1/N-5yc...splay?langId=-1&storeId=10051&catalogId=10053 here is the foam

And I am trying to research what adhesive to use. I found that contact cement is what I need, but water based, solvent based, neoprene based?????

I think I found that solvent based is best, but someone mentioned that it has "issues," what are they?

I also heard good things about 3M's Fastbond 30, but it is water based and everyone says that water based sucks, or takes a lot of effort to use correctly...?

Please help me, I am completely lost


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## precisionworks (Jan 1, 2010)

3M Super 77 is a solvent based contact cement in spray form:

http://solutions.3m.com/wps/portal/3M/en_US/3M-Super-77/Super77/

About $10 for a 16 oz can, which does quite a bit. Been around forever, and widely used. You'll want to leave the windows down until there is no solvent odor, which may take a while depending on the temp where your car is stored.


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## KowShak (Jan 2, 2010)

07accordEX said:


> I think I found that solvent based is best, but someone mentioned that it has "issues," what are they?


 
The biggest issues are that the solvent in solvent based adhesives can dissolve / melt / distort things that aren't resistant to the solvent, i.e. your foam may disappear when you apply the glue to it. Plastics are about the worst sort of materials for being dissolved by solvents, which brings about the questions you have to ask, what is your foam made from? Will a solvent based glue dissolve it? What you can do with some contact adhesives is to apply it to the non-porous thing you're trying to glue (metal / foil rather than the foam) and allow it to become tacky (i.e. no longer wet with solvent) before you apply your foam, hopefully that will reduce any risk of dissolving your foam.

You also get issues related to breathing solvent vapours, again the issues depend upon the solvent, some people can be more affected by solvent vapours than others.


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## gadget_lover (Jan 2, 2010)

The question of water based adhesive was also raised. The problems include; 

1) will the glue be able to cure when trapped between large surfaces?
2) Will it get wet enough (rain, carpet shampoo, car washes) to loosen the adhesive?

Many contact adhesives are used by putting a very thin coat on both surfaces, then allow them to almost dry before putting them together. Most of the solvent is gone by the time they are joined. The bond is instant. 

Daniel


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## VegasF6 (Jan 3, 2010)

Might I suggest you find a local upholstery supply store and see what they have available? As I recall (my grandfather was an upholster) everything was solvent base, and didn't hurt the foam in the least. I was just a kid, but I do remember him cleaning out the paint sprayers (or glue sprayers as it were) with gasoline .

Foam rubber should be more solvent resistant than say styrofoam but either will work. As gadget lover explained, whenver I have used an aerosol can of 3M adhesive, I would apply to both surfaces and let dry mostly before pressing together, but I don't really remember my grandpa even waiting. But, again, it was long ago. Then get a rubber roller to roll out the bubbles.

I take it you are using this for heat proofing or sound proofing, like dynamat?


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## LukeA (Jan 3, 2010)

What kind of foam? 3M Super 77 melts pink insulation foam.


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## 07accordEX (Jan 3, 2010)

Thanks for everyone's input, but I don't know what type of foam it is because I do not have it yet. But, it's kind of like a car sun shade (I think). I just know it is a layer of lots of little enclosed cells (closed cell foam); but it is a plastic-ish foam. Not styrofoam and also not the type of foam found in Pelican cases.

I am pretty sure it will not dissolve it, but I just need something strong that wont fade when under stress that a car goes under (being a little damp, extreme temperatures, vibrations, etc).

I was going to use 3M's Spray Adhesive 90, but contact cement is much cheaper, and I heard the 77 stuff is weak and only strong enough for arts and crafts.


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## LukeA (Jan 3, 2010)

Well the product you linked to is kind of like a sunshade but is described as having a non-woven cotton fiber fill, which, needless to say, will not be affected by any contact cement. Also, the fill is separated from any adhesive by impermeable foil, so if you're just using the product to which you linked and not additional external foam, you will have no problems with solvent cement.


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## 07accordEX (Jan 3, 2010)

But what kind is good? Is the normal DAP Weldwood stuff at homedepot good?


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## LukeA (Jan 3, 2010)

DAP Weldwood or 3M Super 77 will be fine unless you are applying it directly to expanded polystyrene.


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