A sticky problem

PJP

Peter/Pedro/Hey you
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Peter
I see from your posts that most of you seem to paint and then add bits, (e.g. undercarriage doors). How do you get the little sods to stick?

I've tried most adhesives (liquid poly, plasweld, Gators, superglue thick and thin) with little success. Do I need to take those tiny areas down to plastic again to get it to stick?

If I can get this sorted I'll be able to get on with the complicated undercarriage door systems on my Polikarpov I16 which should have been included in the Eastern Front GB.

Thanks in advance for tolerating a silly question!

Pedro
 

stona

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Steve
Not a silly question at all.

The order and method of conctruction varies from person to person but the bottom line is that you won't get two pieces of plastic to join properly if one or both of them are painted.

Solvent type glues like liquid poly and plasweld dissolve the paint and make a mess in what should be the join and superglues may do the same or,at best, glue the two layers of paint together which is not what you want.

I tend to make little sub-assemblies as far as I reasonably can and then paint these. To stick these together,or add something like an undercarriage door or antenna, I remove the paint from the areas that will be glued. I use acrylic paint and this can often be done with my built in paint scraper....a fingernail. If not the back of a blade will do the trick.This often means that some kind of touch up of the paint will be required once the parts have been successfully glued in place. It's boring to break out the airbrush to spray a couple of tiny touch ups colour but it's the only way I know!

Cheers

Steve
 
F

Fenlander

Guest
Oddly, I have never really thought much about this as it has never been a big issue. I don't do anything. I tend to find that liquid poly melts and welds the plastic through the paint (I only really use acrylic so cannot say for enamel) Even wheel doors and bomb bay doors hold OK. So long as you are sparing with the glue and do not flood or scrub it on, the paint generally does not get messed up, or I should say it doesn't for me. Have to agree re superglueing two painted surfaces together. That joint, assuming the superglue does not penetrate the paint and bond to the plastic as does liquid polly, will only be as strong as the adhesion of the paint to the plastic.

Interesting question, will look forward to see what others say.
 

yak face

Wossupwidee?
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tony
Hi peter. graham and steve are both spot on, youre always best removing any paint from the surfaces to be joined if you want a good bond, the only exception to this is such things as canopies or very small items that dont need a mega strong bond , when you can use something like gator grip or formula 560 which will dry clear ,and in the case of clear parts, not attack the plastic.cheers tony
 

stona

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Steve
Just to clarify Graham,I find that paint in a join made with liquid poly (in my case Tamiya Extra Thin is my weapon of choice) will seriously weaken the join. On a larger seam it seems to effect the even "melting" of the plastic and I end up with a weak seam with paint in it that then needs a lot of work. I even clean the paint off the end of an antenna,cannon or,everyone's favourite,pitot tube as well as cleaning out it's locating hole with a microbit. I want the plastic to melt and give me a nice solid and cleanable join. The best way to fill any tiny gaps is with that little ooze of "molten" plastic. It's really not difficult to do.

I'm with Tony on canopies and the like,Gator's Grip or Kristal Klear do the job. I used to use a watchmakers cement which was very strong but I mislaid it (small tube!) and have not bothered with it since!

Cheers

Steve
 
F

Fenlander

Guest
Good point Steve, I will clean up my act a bit, been a bit lazy I suppose lol. Odd what you don't think about isn't it?

That is why I love it when someone asks a basic question, gets people thinking and reinforces the fact that there is no such thing as a stupid question.

I darn't slam a door now in case my models fall to bits :laughing:
 

stona

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Steve
\ said:
I darn't slam a door now in case my models fall to bits :laughing:
I don't think there's much chance of that!!! You did make me splutter on my cuppa though. I guess it just shows once again that everyone has there own method. As you say,it also demonstrates what a very good question was originally asked.

Cheers

Steve
 
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