20 replies to this topic

[Jeff Fischl]

I just completed my first paint job on a 1/24 slot car body and when i bend the body slightly the paint chips off. I washed it thoroughly and dried. put 3 light coats on . Used Testors one coat Lacquer spray paint blazing black.Any reason why this happened?

[PCH Parts Express]

It looks like you did not use paint that is made for use on Lexan. Sometimes these paints fall off. Maybe switch to a paint formulated for Lexan.

 

Parma paint 

Tamiya (for Lexan)

Pactra

and others

[Noose]

Duratrax is another one especially since the Pactra RC paint is no longer made (but some still around).

 

If you choose to airbrush paint then you can also use the water base Parma Faskolor.

[John Streisguth]

I use Createx, similar to Faskolor but a bigger range of colors.  The standard Createx is actually designed to be heat set onto clothing, so using a hair dryer speeds drying time and also makes it stick better.  I also undercoat with their gloss topcoat, makes it a bit more resistant to scratching

[Michael Rigsby]

Also a Createx user.

[Jairus]

Did you sand the body before painting?
I always sand with 000 steel wool and then wash out with soap and water.
The sanding gives the paint some "tooth" to grab onto.

[Mike Patterson]

Maybe I'm just lucky, but I have never sanded the inside of a lexan body prior to painting, and have never had the paint flake off. I spray the inside with Simple Green, and scrub it with a toothbrush, making especially sure to get in to all the nooks and crannies. Then I rinse it with tap water, and dry with a cotton towel. Sometimes a Q-tip is needed to dry the aforementioned nooks and crannies. This method has worked for me using Pactra spray cans, and Createx and FasKolor airbrush paint.

 

And watch touching the inside of the body with your fingers. When masking a body, I use tweezers and an X-acto knife to position things, and a burnisher to firmly attach the tape/film. Cleanliness is next to godliness. or so I've been told.

[Gator Bob]

Jeff, you didn't say if it's Lexan or PETG. 

 

Did you sand the body before painting?
I always sand with 000 steel wool and then wash out with soap and water.
The sanding gives the paint some "tooth" to grab onto.

 

Exactly, a tried and true prep method .. and a quick wipe with alcohol after masking.

[Pablo]

Thanks, Gator Bob, for being the only one to recognize the importance of knowing what body material we are talking about before offering advice on the possible cause of Jeff's paint chipping problem.  Frankly, I don't understand how anybody can hazard a "guess" here, unless they know if Jeff's body is Lexan, or non-Lexan. He said it is a "slot car body" - slot bodies are made with several different varieties of plastics.  Not all paints work well on all plastics.  Gator Bob gets it.  So, Jeff, what kind of plastic are we talking about ?

[Ramcatlarry]

I have used Testors 'one coat' and its cousin 'model master' lacquers on both lexan AND 1/32 and 1/24 hardbody models.  Obviously a primer works better on the hardbodies, but the 'model master' seems to work better for me - especially on lexan well cleaned with simple green or alcohol.  Pet-G is one tough plastic to get a bond with paint.

 

Sometimes the backing coat will help seal the color coat and sometimes shrink it and make it chip.  Coat the inside with 'shoo-goo' on clear bodies to help them keep the paint on the car.  Clear-coat hardbodies or use floor wax like 'future'....

[Jeff Fischl]

Lexan body.

[Pablo]

Jeff, I wish you had specified that in your original post. Your problem is very simple, you used the wrong paint.

Testors "One Coat" Lacquer spray paint is not intended for use on Lexan.

[Jeff Fischl]

Thanks all for the help sorry didn't state that it was a lexan body

[Pablo]

No problem, Jeff. 

The bottled acrylics (water based) Faskolors, Createx, Model Master, Pactra, etc. all work on Lexan.

Evidently you found a lacquer that doesn't like Lexan, but there are many others that do work fine for it - Testors, Tamiya, Pactra, etc.

 

Read the fine print on the "one coat" paint you used and I'll bet it doesn't say "for use on Lexan"

[Bill from NH]

In addition to the acrylics Pablo listed above, most water-based hobby craft acrylics by Plaid, Deco Art, Delta Creamcoat, Liquitex, & Golden adhere well to lexan also. I test a new brand of paint by doing a brushout on a scrap of lexan, let it dry for 24 hr., then see how scratch-resistant it is to a pointed wooden toothpick or a wooden skewer. The only exception to this is Delta Creamcoat, it requires 72 hr. to adhere well to lexan. The last line of acrylics I found not to adhere well to lexan is the Jo-Ann Fabric brand of acrylics. It scratched off easily. There has been a few other brands I found that didn't adhere well too. 

[Shruska55]

I use Createx, similar to Faskolor but a bigger range of colors.  The standard Createx is actually designed to be heat set onto clothing, so using a hair dryer speeds drying time and also makes it stick better.  I also undercoat with their gloss topcoat, makes it a bit more resistant to scratching

 

John,

 

Your quote was written back in 2014 regarding a paint flaking question. When you stated 'undercoat with their gloss topcoat" does this mean that you spray the gloss on the clear lexan, then paint on top of that? My issue isn't flaking so much as how easily the paint scratches.

 

I'm using an Iwata BCR per recommendation. I'm using Createx paints, per board suggestions, diluted per Noose starting recommendations of 80/20. I've added Balancer per Createx and am using the PSI recommendations per Createx. This issue has occurred with several paints in the Createx family. including the Opaque and Wicked Colors. Not as bad with the Opaque.

 

I'm wondering if I'm over/under diluting or not laying enough paint. and whether a clear finish coat will help. Or as you recommend, an undercoat.

 

I'm just getting started again with airbrushing and have followed the cleaning protocols posted here. I haven't tried a steel wool rub as yet, but will give that a go next project.

 

Suggests are very welcome.

 

Thanks,

ScottH
 

[MattD]

Scrub with an SOS pad, use some 400-600 sandpaper.   Spray with 409 or similar cleaner, rinse with water.    Dry with a hair dryer and mask, warm it up with hair dryer again and .....use Testors, Tamiya or Duplicolor lacquer.   It's the only paint I've used on new bodies or old bodies with no issues.    Some  people say the lacquer will warp a body in a few years.     I say in a few years no one around will care anyway.

[Rotorranch]

Personally, I have not scrubbed a body with steel wool since the 60s.

 

For the last 30+ years on Lexan bodies I use the Pactra RC colors paint primarily. I've had great success with it.  The Duratrax paint is supposed to be the same formula as the Pactra.

 

I'm experimenting with the Tamiya laquers some lately. Jury is still out at this point.

 

I've never had success with the water based paints.

 

JMHO

 

Rotor

[Noose]

Spray a light coating of Future / Johnson’s acrylic floor wax after the paint dries. It prevents the scratches and makes it easy to wipe oil,etc. off the inside of the body after racing.

Make sure you then thoroughly clean your air brush.


Sent from my iPhone using Tapatalk

[Rotorranch]

I do thoroughly wash all bodies with warm water and Dawn dish soap.

 

Rotor

[MattD]

Most of the bodies I paint we race.   They  get used and abused, these are not shelf queens.    Some of the vintage bodies do just set on the shelf.