# Problem Gluing Plastic Model



## MtRR75 (Nov 27, 2013)

I have started building some of my structures -- all plastic ones so far. I am fairly meticulous in this process. For walls, I tape the 2 walls together with painters tape, they apply just a few small dabs of glue (usually with a hatpin) to the inside of the joint -- not the whole joint. Then I brace the walls with a right angle block and let it dry for at least several hours. Then I add a second wall in the same manner, and so forth. By not gluing the whole junction, I can usually disassemble a junction if I need to fix a problem. This has saved me several times already.

My first kit was a Tyco blacksmith shop. The second was a Life-Like engine house. The third (still in progress) is a Bachmann coaling tower and sand house. My gluing technique worked fine for all three of these kits.

Now I am starting on an Atlas interlocking tower. Here is where the problem is. I assembled the four walls and the base using this technique. One of the wall joints came loose. No problem -- I expect this from time to time with my minimal glue technique. I redid the joint. Then it and another joint came loose. So I redid both of them. Then another joint came loose. Then I GENTLY pulled the other joints and ALL of them fell apart. The glue blobs remained attached to one of the pieces, but I was able to EASILY scrape them off using my fingernail. There were only very slight indications on the pieces where the glue had been. The walls are brick red, and the base is very dark gray. But the glue blobs were nearly clear -- just a light pink tinge.

Obviously what is happening is that the glue is not dissolving the plastic enough to make a strong bond before the glue dries. Is there something different about the plastic that Atlas used in their kits vs. the other manufacturers? Do I need a different glue? I am using Testor's model cement for plastic. The kit directions (written in 1962) say to use "model cement".

Any ideas?


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## Torsion (Dec 25, 2013)

I usually use a plastic weld solvent. "Plastruct plastic weld" or similar brand. Sometimes I"ll also use super glue. The solvent bonds pretty fast just seconds. Then let it cure for a few minutes and move on.


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## Cycleops (Dec 6, 2014)

You need to be careful when using Plastic Weld its much more aggressive than regular poly cement but with your technique should be fine.


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## DonR (Oct 18, 2012)

Back a few years ago I used Plastic Weld on several downtown
kit buildings. Assembly was easy enough but after a year or
so the glue seemed to dry out and release. The buildings literally
fell apart.

I've been using the cheapo Super Glue from Harbor Freight for
my scratch building of late. Just a tiny bit does a good job and
sets very quickly. 

Don


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## Torsion (Dec 25, 2013)

Back in the 90's I got heavily into building armoured vehicles in 1/35 scale. Intered many IPMS events and took home many awards, even had one displayed in Fine Scale Modeler. I still have these models and used plastic weld on most. None have fallen apart. So I don't know the cause of that. I've had good results with plastic weld and super glue with an accelerant.


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## CTValleyRR (Jul 26, 2014)

I use Testors liquid cement inthe black square container with the needle applicator.

I have had that problem from time to time. Try washing the pieces to remove any oils or mold release agents thst may be protecting the plastic.

I also find it's a good technique to pass a mill file a few times over each surface to be joined. In addition to smoothing it out for better adhesion, the file will also remove impurities and add some "tooth" for your adhesive to grab.


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## Cycleops (Dec 6, 2014)

Zap do a CA specially for plastics, don't know if its any better than Don's brand X.http://www.supergluecorp.com/?q=zap/zap-glues/plasti-zap


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## MtRR75 (Nov 27, 2013)

Thanks for your responses. I'm still thinking about which product to try first.


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## Wood (Jun 9, 2015)

*MtRR75 posted: I'm still thinking about which product to try first.* 

I might be late to the party, but I will pass along my use of Gorilla Super Glue. It is an acetate like Zap but you can buy it in three different consistencies. Super thin good for tight small joints, Regular Super Glue which is gap filling and Gel Super Glue which is almost like a putty and you can fill and mold it.

The big advantage, from my point of view, is that Gorilla Super glue has a longer set time then most super glues. 15 to 30 seconds. The advantage being that you can properly place and move the parts without worrying about the glue locking in place. Now if you do want an instant set you can use the standard acetate accelerant spray which will give you an immediate set.

Several of my projects are 5+years old and I have not experienced any breakdown in adhesion.


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## leadsled (Dec 25, 2014)




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## MtRR75 (Nov 27, 2013)

Wood said:


> *MtRR75 posted: I'm still thinking about which product to try first.*
> 
> I might be late to the party, but I will pass along my use of Gorilla Super Glue. It is an acetate like Zap but you can buy it in three different consistencies. Super thin good for tight small joints, Regular Super Glue which is gap filling and Gel Super Glue which is almost like a putty and you can fill and mold it.
> 
> ...


Thanks for the info. With the holidays and a major rebuild of my control panel in progress, I have not gotten back to building structures, yet. I will consider your suggestion.


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