Paint adhering to clear parts ... canopies etc

[Stressy]

Since I moved away from enamels a few years ago now its been a constant struggle to get canopy frames and the like to keep their paint stuck on; bits often peel away with mask removal. Airfix ones seem particularly troublesome.  Obviously I give the spru a good wash first and thereafter I've tried various things like dipping the whole part in Klear before applying paint. I've also tried Tamiya and Mr Color as undercoat of an appropriate colour for internal framing (including Mr Surfacer 1500). I wondered, but not yet tried,  starting with a coat of Humbrol Clear, which I prefer to the acrylic Klear since it will melt into any later application of it should some sort of rework prove necessary. 

I've been making aircraft for a long while now and can look back at perfect canopies from 20 or more years ago  so why has the change to acrylics given me such trouble when it comes to painting clear sprue parts - any suggestions? 

[Black Knight]

If you are using water based acrylics you can gently scrape the paint off with the point of a cocktail stick

I find acrylics have a greater tendency to get under masking tape no matter how well you rub it down. Greater care is needed in painting up to masking tape

[flyboy2610]

Acrylics really need a primer under them. They do not have solvents to bite into the plastic. The primer does not necessarily need to be acrylic, however.

[Mark Harmsworth]

First question - are you using an airbrush or hairy stick? Second question - what do you wash them with?

 

I use an airbrush and the first job in most of my builds is to get the canopies off the sprue, file off any untidy bits then dip in Klear, leave at least 24 hours (often longer) and then apply masks.

 

Then airbrush interior colour (I use xtracrylics), leave for at least 24 hours and then airbrush the exterior colour.

 

I've never washed transparencies nor do I use a primer on them (not deliberately anyway).

 

This was a recent 1:32 Lancaster canopy and front turret done like that:

 

Mark

[Stressy]

Thanks for the reply. I use an airbrush.  I wash with a mild shampoo,  typically baby shampoo. I have used Klear but found that if paint got under the mask ... or the fit was bad, either requiring some of the paint to be taken off with a cocktail stick or point of a scalpel, then if the clear gets damaged and has to be touched up the original Klear left an edge that was visible through the new layer. The advantage with Humbrol Clear coat, which is the equal of Klear in giving the transparency a glass-like finish, is that the new coat will melt into the old such that no 'edges' are visible. Currently I apply the Clear at the end to each pain which also seals the acrylic paint free edges to the plastic helping it stay in place. The problem with my method is that I  end up having to get a small paint brush out to retouch the previously sprayed framing,  which is frustrating having used masks in the first place!

 

Regarding your method, having painted the transparency first, what do you do if the canopy is a bad fit to the fuselage and needs work?

[Mark Harmsworth]

14 hours ago, Stressy said:

what do you do if the canopy is a bad fit to the fuselage and needs work

I prefer not to attempt any serious work on a transparency because of their brittle nature - they can crack too easily.

 

I often attach a canopy with a couple of drops of ca glue (the dip in Klear protects it from fogging) - then any gap filling I generally do with pva glue because it can be smoothed with a damp brush and then painted when cured. And I also will often do a little touch up on the canopy framing with a small brush at the end - I did on that Lancaster.

 

With a limited run kit where I might worry about fit I will do a test fit at the beginning to see what might be needed - but again I tend not to do any surgery on the canopy.

 

Hopefully helpful.

all the best

Mark

[Pete in Lincs]

Your peeling problem may be oils in the shampoo. That glossy look has to come from somewhere. Swap to washing up liquid. It is the usual thing on here and it might work for you too 

[Stressy]

Good point I'll give it a go. 

[Mike]

18 hours ago, Stressy said:

Regarding your method, having painted the transparency first, what do you do if the canopy is a bad fit to the fuselage and needs work?

I'm a firm believer in preparing the canopy by sanding/fettling it, dipping it in Klear, removing the Klear from the attachment surfaces and giving the edges a coat of permanent black marker to reduce internal reflections.  Then I glue it to the model before painting, usually using GS-Hypo cement.  Then I will do any remedial work on hiding the join with putty or black super-glue (CA) on the outside only, as real aircraft usually don't have visible seams around their canopies.  If you're filling, be very careful it doesn't squeeze through to the other side, as that will look horrible.  if you're using CA, make sure there's plenty of ventilation if you don't have access to non-fogging CA.

 

2 hours ago, Pete in Lincs said:

Your peeling problem may be oils in the shampoo. That glossy look has to come from somewhere. Swap to washing up liquid. It is the usual thing on here and it might work for you too 

I bet that's the case, although I never wash my kits because I'm too impatient

 

Finally, apply the masks, burnish the tape down well, but not too hard, and do the painting thing.  peel them away carefully right at the end of the painting process, to keep your canopy as clean as you possibly can.

 

The pic below is the canopy of my Wildcat, which I used that process on, but this was an inside/outside Tface mask from Eduard, so you paint the interior with the correct colour before you apply it to the model, remove the interior masks before you glue the canopy in place, then proceed as normal.

 

 

Other than what I've just outlined above, I did nowt special to that, and benefitted from the excellent fit of an Eduard canopy.  If you're going down the Tface route, apply the exterior masks first, as it'll help you line up the interior masks where there aren't raised canopy lines to guide you.  I'm a BIG fan of these things, as they make the canopies look more realistic and 3D to my eyes.

[Stressy]

Well never heard of  GS Hypo or black super glue but I've just ordered both so will give them a try!

Thanks 

[dnl42]

Yes, be careful on filing or sanding canopies, they can and do crack. 

UV-curable glues work great of clear parts! It's now my goto as they cure as soon as that UV light hits.

 

Mike, that's a fine, fine job on that Wildcat! 

3 hours ago, Mike said:

I'm a BIG fan of these things, as they make the canopies look more realistic and 3D to my eyes

@Mike I've had a couple of those sets over the years, but skipped in inside masks as I thought it would look funky. Would you mind showing a close-up of the canopy? TIA!

[Mike]

52 minutes ago, dnl42 said:

Would you mind showing a close-up of the canopy? TIA!

Can't right now, as it's in the cabinet, I'm nowhere near it, it's dark and it's raining, but the effect is brilliant (I mean the simplicity and results of the set, not my efforts).  Whenever there's a Tface or Inside/Outside mask available, I'm using 'em

[evilbobthebob]

I have also experienced a lot of peeling with canopy painting. It's definitely at least partly because I use acrylics, and partly that I use AK acrylics a lot which are vinyl-based. I also tend to leave masks on too long so the paint forms a bond over the mask, which leads to tearing and lifting rather than a clean edge. I only really "solved" this recently by using Vallejo acrylics and making sure I take the masks off relatively quickly. Of course that makes it difficult to do any sealing afterwards with varnish. It's a conundrum!