"Greenhouse" masking question

the Baron

 

 

plasticjunkie

...It gets a bit confusing with water based and solvent based acrylics.

 

 

 

To say nothing of the old Pactra line of water-based acrylic enamels

 

Oh yes fogot those. Just went to Hobby Lobby today and saw water based oil paints in tubes.   

plasticjunkie

...It gets a bit confusing with water based and solvent based acrylics.

To say nothing of the old Pactra line of water-based acrylic enamels

Just my own experience, whether enamel, acrylic or anything else, I airbrush the paint really thinned in multiple/several layers. Rough mix ratio, 3 parts paint, to   5 parts thinner, adjusted as deemed required. This seems to be a fix for the issue of thick paint not releasing from the mask, it's been a very long time since I've experienced a ragged mask line on any surface.

Also, I've had some surfaces masked for a long time and still no mask line or lifting problems. My most used masking is with Tamiya tape, commercial masks or Frisket paper.

Patrick

Try “Monotrx Masks”. 99.9% good quality.

fritzthefox

I think water-based acrylic paints have poor adhesion in general, which can create masking problems. Water-based acryic relies on polymerization for adhesion, so it is less inclined to stick to surfaces and more inclined to stick to itself. Consequently, it likes to peel off in chunks. You will likely need a very low tack tape for masking them, and the longer you leave the tape on, the greater the chance of a problem. I rarely have a problem with lacquer based acrylics, which bite into the surface and will tolerate masking better. I've used bare metal foil with them, and the only nuisance is getting the foil off. 

A good lacquer primer may help, or roughing the painting surface a little before applying the paint. Clear plastic has very little tooth for paint to grab onto.

 

Like u said, a solvent primer ensures proper adhesion when using acrylics. MM Acryl will peel right off if no solvent primer is used and heard of the same with Vallejo.

Tamiya acrylics can be thinned with LT and are not water based so they adhere very well as is with no primer.

It gets a bit confusing with water based and solvent based acrylics.

I think water-based acrylic paints have poor adhesion in general, which can create masking problems. Water-based acryic relies on polymerization for adhesion, so it is less inclined to stick to surfaces and more inclined to stick to itself. Consequently, it likes to peel off in chunks. You will likely need a very low tack tape for masking them, and the longer you leave the tape on, the greater the chance of a problem. I rarely have a problem with lacquer based acrylics, which bite into the surface and will tolerate masking better. I've used bare metal foil with them, and the only nuisance is getting the foil off. 

A good lacquer primer may help, or roughing the painting surface a little before applying the paint. Clear plastic has very little tooth for paint to grab onto.

Try “MonoTex Canopy masks”

I use Eduards masks and Tamyia Silver Plate. I have never had a problem. I also mask the back side of the greehouse with blue tape. This is the greenhouse for a 1/48 B-29. Masking this by hand would not work for me.

Whether I need to use hobby knife to outline tape or mask edges depends on how many coats of paint I put on.  For just a coat or two, I usually don't.  However, if some problems occur that require more coats than that on airframe, then I find I must use the knife.

WWII_AC

I just got through masking a Tamiya F4U-1A canopy and front windscreen. Tamiya was kind enough to supply the masking tape.

But, the whole time I was applying the mask I kept wondering why do manufacturers still mold the canopy glass and the canopy frame as a one piece clear part anyway? Given the improvements and advancements in the manufacturing process over the last 4 decades you would think they (someone) would have found a way to mold the clear glass separate from the frame - using a recess to allow the glass to sit flush with the frame once glass is applied. This whole masking tape thing just feels so...1970's!

 

Sounds good in theory but try assembling a complex greenhouse like a Val, Judy, etc. will be quite a project. I rather use commercially made paint masks when available to make it an easier task.

I just got through masking a Tamiya F4U-1A canopy and front windscreen. Tamiya was kind enough to supply the masking tape.

But, the whole time I was applying the mask I kept wondering why do manufacturers still mold the canopy glass and the canopy frame as a one piece clear part anyway? Given the improvements and advancements in the manufacturing process over the last 4 decades you would think they (someone) would have found a way to mold the clear glass separate from the frame - using a recess to allow the glass to sit flush with the frame once glass is applied. This whole masking tape thing just feels so...1970's!

The only way I see that happening is if too much paint was sprayed. For dark colors I spray a light coat of black first. This thin translucent black coat will cut down on the final paint color coats eliminating paint buildup. For light colors I shoot a light or medium grey first.

It's  a good idea to remove the masking asap but sometimes due to certain situations, the masking will remain in place for weeks at a time. So far, I've  had no issues in doing so.

I haven't had a problem, using enamels.

I use Tamiya tape...unless it's an Eduard kit, that comes with masks. Even after the masking has been in place for weeks, I still haven't had any issues with it peeling up more than it should.

out04

Can't pull it immediately when I have to layer two colors and weather to match the airframe.

 

Exactly. I usually paint with the canopies in place, even if I plan to have it open on the finished build. The masked closed canopy protects the cockpit. So it's dip in Future, allow to dry, mask canopy, glue/tack glue in place, paint, gloss, flat, and finally remove mask and open up canopy. I have literally had canopies masked for years on some shelf queens.

I'm finishing up an LT-6 at the moment. It took half a day to mask the canopy. I'd sure hate to screw up a paint job trying to peel off the masking. I also have an A-24 getting ready for paint. Haven't masked the canopy yet.

route62

I always give a light trace with a sharp razor prior to peeling the mask since there are usually several layers of paint and clear coats.  

 

Can't pull it immediately when I have to layer two colors and weather to match the airframe.

It is a good idea, once the frames are painted, to immediately remove the mask. This prevents chipping, especially for glosses.

I always give a light trace with a sharp razor prior to peeling the mask since there are usually several layers of paint and clear coats.  

I get the same issue with enamels, thats whether i am useing Tamiya tape or Euard masks.