I recently built a set of A-line thrall cars. I primed them with Model Masters primer and painted them with Scalecoat II spray paint. They looked great but after they dried, there was quite a bit of "alligatoring" in the paint. I have stripped them and have them ready to paint again. I am thinking that there may have been some type of reaction between the primer and the paint since I used two different brands. I know that Scalecoat paint does not like other primers, so maybe the same applies to paints. Any thoughts before I paint again??
Not enough information
There are both acrylic and lacquer based MM thinners. Also how did you thin the scalecoat?
Henry
COB Potomac & Northern
Shenandoah Valley
anthony61 I am thinking that there may have been some type of reaction between the primer and the paint since I used two different brands. I know that Scalecoat paint does not like other primers, so maybe the same applies to paints. Any thoughts before I paint again??
I am thinking that there may have been some type of reaction between the primer and the paint since I used two different brands. I know that Scalecoat paint does not like other primers, so maybe the same applies to paints. Any thoughts before I paint again??
I think that's a fair assumption, Anthony. Use Scalecoat II primer and paint to insure compatibility. I believe their literature may also suggest that.
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
Henry, the paint was Scalecoat II in their spray can line. The primer was Testors Model Master in their spray can.
How soon did you paint the Scalecoat over the Testors? They are both enamels, but if the Testors was not completely dry, that is no smell was present which may take a week then the problem you had would probably happen.
By the way Scalecoat requires no primer per all that I know, and I never use any.
Rick Jesionowski
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Scalecoat's spray cans put out a lot of paint. Increasing working distance might help. I agree the primer may not have cured completely, and usually try not to mix paint brands on a project. Airbrushing gives you a lot more options.
I let the primer dry 24 hours. It was dry to the touch. I am going to try and spray them without primer.
I usually use a airbrush, but was trying the spray cans. They do put out a lot of paint.
I could be wrong but I think Scalecoat recommended drying times of 2-3 days up to a week??? And I believe I read somewhere that even if paint is dry to the touch and/or doesn't smell it may still not be completely cured.
Asa long time Scalecoat user, I'm sure you had a reaction to the primer - you really don't need the primer on bare plastic, two coats of paint maybe, but only if you don't get good coverage in one coat.
Sheldon
Hi Anthony,
Sorry to read of the problem that you encountered.
I agree with Sheldon that, based on what you've posted, it's very likely that there was an adverse chemical reaction between the primer and the SC-II paint.
By "Alligatoring" I'm assuming that the paint started "wrinkling" or "lifting".
Scale Coat II is actually a slighly weakened version of automotive paint. Very durable and tough product. Generally a separate primer underneath it is not needed, unless you are applying a paint over bodywork or a light color over a contrasting foundation (example: White over Red). In those scenarios, Scale Coat's primer provides good hiding and flowout qualities.
Can you post photos of your model?
anthony61 I recently built a set of A-line thrall cars. I primed them with Model Masters primer and painted them with Scalecoat II spray paint. They looked great but after they dried, there was quite a bit of "alligatoring" in the paint. I have stripped them and have them ready to paint again. I am thinking that there may have been some type of reaction between the primer and the paint since I used two different brands. I know that Scalecoat paint does not like other primers, so maybe the same applies to paints. Any thoughts before I paint again??
"I like my Pullman Standards & Budds in Stainless Steel flavors, thank you!"
dti406Scalecoat requires no primer per all that I know, and I never use any.
.
This might be mostly true, but I found out the hard way that if you spray Scalecoat 2 Daylight Orange you MUST prime the surface with flat white. There is simply not enough pigment load in the Daylight Orange to cover any other surface.
Other yellows and oranges probably have similar requirements.
-Kevin
Living the dream.
The thinners used for both Scalecoat I and Scalecoat II contain naphtha and xylene, either of which may have reacted with the previous paint, especially if it hadn't fully cured.
Wayne