Gluing Brass to Plastic

Some sort of clear epoxy maybe?  I mostly use Model Master liquid cement, but never tried it on brass to plastic, says it's for plastics though.

Any picture of the situation?

 

Couple thoughts...

 

If your plastic platform is one of the so-called slippery plastics...e.g., Delrin or its generics...you may not succeed.....even with epoxy.  One test I'd try to evaluate the plastic would be to put a small drop of a weld-type plastic adhesive...e.g., Tenax, Pro-Weld, Same Stuff, etc....on the plastic in an inconspicuous place.  After a few seconds, check with your finger or a toothpick to see whether the plastic has been softened by the adhesive.  If so, your choices are better....epoxy might work....I would've thought CA would, too.

 

That said, is there any chance you could drill some small holes near the edge of the platform into which you could insert the railing posts?  Anything like that that gives some mechanical advantage will help with an adhesive bond.

 

If the platform posts were long enough, you could bend them for a short length at 90-degrees to provide a tang to bond to the underside of the platform.  The more surface area you can get between the two parts/materials, the better the chance of success.

 

But, a picture or two might get additional forum ideas.

 

FWIW, always....

 

KD

KD:

Thanks

I am building an HO scale refinery for a customer that consists of custom parts plus kits. The kit I am having problems with is the Walthers refinery. The platforms are molded in yellow plastic and are very thin - maybe 30 mils (.030 in) so no chance for holes and yes it melts when I use Plastruct Plastic Weld on it.

I would post pictures except after two days of frustration I tossed the brass railings and am now custom building my own platforms from 40 mil sheet plastic and using Plastruct styrene railings. I asked the question because no doubt somewhere down the line I am going to be dealing with brass/plastic again.

Try thinned GOO plus a drop of ACC

positively the way to go Walthers Goo and Acc

Another vote for Walthers Goo and CA.

This was done Brass to painted Aluminum.  The paint is a good grade primer.  Done with a medium thick CA.

A styrene plastic strip was applied to the brass angle to add thickness on the edge.

Styrene to Aluminum.

There is a learning curve to Cyano-acrylates. There are at least three different thicknesses.  (Thin), (Medium), and (Thick),  also a (Gap filling).  The speed of set is kind of relate to the consistence of the CA.  Thins set fast, thick slow.   There is the possibility with Thin, that the CA has set before assembly.  Using medium and thick there is an accelerator, that when sprayed on the assembled parts, enhances set time. Once open there also appears to be a shelf life.   Old CA may not work well.   

Joe,

Using the CA with an accelerator should work fine. I use Plastruct CYC-3 and CYA-3. If it does not, I would try sanding the brass a little at the glue joint, and try the CA with accelerator again. I have done this a number of times without a problem.

 

Alan Graziano

 I switched to a glue that seems to work on a lot of stuff. It's the Gorilla brand super glue, that Korber's owner recommended. The stuff I was using to build scratch models would release if handled semi-roughly. Now nothing seems to come lose anymore since I switched.

 I wonder if that would work here.

Ok, it's something that I ran into by chance years ago that I and many others make use of particularly for mixed materials and for when of the surfaces has some porosity.  Probably have posted this information more than a few times as well, but once more only hurts a little,

 

A discrete film of Goo on the more porous surface and minimal amount(s) of medium viscosity CA on the other surface, e.g., Goo on the end grain of wood and CA on the soft white metal casting that you want to join onto the wood.  Put the 2 together and for chemical reasons that I do not fully understand as yet, they interact (co-polymerization of some sort?), and form a very strong bond.  You have maybe 10 secs to get the parts aligned and to get them apart you'll have to cut them away from each other.

 

I and others has used this to bond together all sorts of materials that other glues and adhesives fail with (e.g., very little works with end grain), and it also retains very slightly some of the flex of the rubber contact cement character which tends to be good for bits that one bangs into repeatedly.