Model Railroading > Handrail painting

Anybody know the best way to paint plastic handrails
without the paint flaking off later.
Thanks
Brian

I have had reasonable results with Model Flex paint.

Problem is that the new "delrin-type" handrails flex and the film of dry paint doesn't, so the paint film cracks and then loses its bond on the engineering plastic and flakes off. Best answer is to not handle the model any more than necessary.

Gary Binder

I use modelflex paint also.

I have been able to overcome the problem by
using a small file using fine grit. I rough up
the area to be painted first. That way the paint has a surface to adhere too.

Note: You have to be gentle in roughing up a plastic
handrail. Rough handling will break the plastic.

Bill

Body shops mix something in their paint when they do plastic bumpers on cars to keep the paint flexible, I've never used it but I've heard of people who have. Anyone know of or tried using this?
Doc

I agree that roughing up the plastic handrails is the ONLY way to ensure that paint won't flake off. The engineered plastic handrails have a very smooth surface (smoother than regular styrene) so the paint does not adhere too well. It is the smooth surface rather than the flexibility that allows the paint to flake off.

I use some flexible sanding files that I found at my hobby shop. This does take a while but it is worth it....as I have had NO flaking once I do this.

An easier way is to find someone who has a "grit blaster" to grit blast the handrails. I used a North Coast Hobbies grit blaster on some handrails at a train show and it took about one minute to grit blast the things!

I think Atlas grit blasts their painted handrails on the GP38 and GP40.

The best method I have used is to paint them and then don't touch them, and keep a bottle of touch-up handy. One thing I do not do but a friend always did was to touch them up with rust paint, it kind of weathers your model as it ages.

I have never tried it, but someone once told me the secret to painting flexible engineering plastic handrails was to use acrylic paint.

Soak them over night in vinegar.This supposedly etches them.I have only done this to one model,but it seems to have worked.

to take some very fine grit sandpaper, and lightly wet sand the handrails, this roughens them up just enough to let the paint get a tooth. Also I have used some good primer before painting, with that and the wet-sanding it should adhere pretty well.
As far as the auto-body shop paint, I remember working at one and mixing that paint, I cant recall the name of the product, but I will tell you when we have painted my IROC-Z, you could punch the front and rear bumper and not a crack would be seen. They also use this paint on Saturns.....dont believe me...come to my house and kick my door, you may crack the panel, but that paint will not move!
Ill try to get the info on the paint, I would check the 3M website though, as I recall it was made by them.
TheHammer
Mark!

http://www.dupont.com/automotive/applications/exterior/bexv978i.html
Here is the stuff you guys were asking about......flex-paint.
Oh and it was via du-pont.com, i knew i used this stuff before
TheHammer
Mark!
also see;
http://www.dupont.com/automotive

I remember someone mentioned a paint that is used on R/C cars. It is a flexible paint that they paint the body shells with.

trainz, It was probably me you heard about the R/C stuff from. Although I've never tried the 3M stuff I have a friend at Dupont who is one of their chemists and he has told me that the flexiable stuff would be too thick for use in hobby applications. He has mixed up paints for me before that are used by the Nascar boys and most of these are reasonably workable but do tend to hide some of the detail on a model kit so I assume he knows what he's talking about. The R/C paint made by Pactra contains a dirivative of the stuff used by Staurn and other car mfg's. Use the R/C white and then paint your models color over the top of that so far none of my models paint has chipped away. Bachman Spectrum handrails going on 6 years now. Good luck!

Kris

Try using a hobby bead blaster. Leave the handrail on the sprue while bead blasting. It will etch the plastic and the paint will adhere. There are small hobby units for this type of work. They use minature glass or alumin beads to etch the part. It will also etch window glass.

I've used the DuPont stuff. It could be mixed with the OLD formula of Floquil but it won't mix well with the new stuff (I don't know about Scalecoat). It helps to some extent with the older (thicker) handrails but with the new thinner ones it is not as good, it will not flex enough and still cracks. Maybe with some of the other tips above this will work better, but at $28 a quart (five years ago) it would be an expensive test if it didn't work.
I still have some of this stuff but I don't paint in the winter (no heat in the garage) so in the spring I will try some of the above etching tips and see what happens.

- Steve
<A HREF="http://www.trainweb.org/csxtimetables/&quot; TARGET="_new">CSX Transportation Timetables</A>

Thanks for all the tips I don't know what to try first
Thank you
Brian