A useful gluing tip for non plastic items

[GrahamF]

One of the more useful tips I picked up from my 30 years building Architectural models [ apart from never getting into it! ]

is that if you need to glue something to plastic that won't naturally bond and melt with your liquid glue because the object in question isn't plastic,

all you have to do is spray the back i.e the gluing side with clear acrylic car paint, which drys in seconds and then when you run liquid glue along the edge of the item 

once placed the acrylic paint melts slightly and bonds to the plastic.

We used to use this a lot when we had to place brass etched window frames to clear perspex windows and also [later] laser cut card frames to perspex.

Yes I too was astonished at this technique when I first heard of it many moons ago.

[Iain]

Thanks Graham - not tried that - I have some photo-etch coming up that I can try that on! 

 

Iain

[GrahamF]

Works even better with Dichloromethane [ MEK ] no glue marks whatsoever as the capillary action is a lot faster.

Graham

[1to1scale]

Here is another trick, when you glue things together with CA, the CA becomes brittle after a few days, and if you accidentally bump it, the parts break off. No way around this, it’s just a nature of the glue. Also it will fog clear and opaque parts.

 

Tip 1

 

However, I recently tried some new stuff, it’s called Flexy CA. They make it in several types, but the theory is, it does not dry brittle, it has a tiny bit of flex. I have two versions, in is Flexy Resin, formulated to grip resin pieces, and another thinner, Flexy PE, to hold metal to resin or plastic. They stuf sets up in about twice the time of “purple” CA, but does not completely harden for 24 hours, so you can separate the parts forcefully, but without damage within a few hours. I have this stuff, a little pricy, but worth it!I tested it with some scraps, and it works very well! 

 

Tip 2

 

CA fogging plastic and clear parts. I solved this problem on the 80’s, by accident. When I was a wee teen, I built a GTO, and glued the clear windows into the body shell using CA glue. I left it sitting with a weight on it in the window with a box fan blowing out the window, two days later, the windows were clear and fog free, I unknowingly discovered this, because the next model I left sitting, and all the windows has frosted with fingerprints, this is where my LHS suggested micro mesh, which worked. However, i was curious why this happened. I started experimenting, and I found that 100% of the time, if there was sufficient breeze past the parts, it would never fog. So, if you use CA anywhere near clear parts, like in a fuselage, then just set it in front of a fan for 24 hrs and let it outgass in the breeze.

[ah100m]

GrahamF-

 

By "acrylic" do you mean (automotive) acrylic enamel or acrylic lacquer?  Can you give me the brand and part number of the clear you use?

 

Thanks

[GrahamF]

On 10/7/2018 at 3:58 AM, ah100m said:

GrahamF-

 

By "acrylic" do you mean (automotive) acrylic enamel or acrylic lacquer?  Can you give me the brand and part number of the clear you use?

 

Thanks

Yes any clear car lacquer spray paint, the stuff to put over the top of metallic paints normally.

Graham