Yet another machine shop

[PuckHog]

Hi Folks,  After some time on other stuff I decided to get back to the machine shop. I needed a busted down donkey engine for the scene and found a SWest resin boiler in the scrap box to start with.
 
I wanted to try out some things I found on the mig forum site dealing with rust and paint and thought this boiler would be a good place to try them out.

  The casting gets a light coat of  "Rust-o-leum primer" found at any hardware store......Randy

[PuckHog]

The casting gets soaked with water and sprinkled with a mixture of table salt and baking soda......randy

[PuckHog]

more pics...

[PuckHog]

the idea is that the salt mix will form a mask that will let the primer color show thru after the top coat is applied and the salt is removed....

[PuckHog]

The top coat I'm using is an  enamel, Model Masters Camouflage Grey, sprayed on out the can.....Randy

[PuckHog]

After drying under lamps for a couple of hours went and washed everything with diluted black acrylics.

[PuckHog]

 Once the washes were dry I used a wornout toothbrush and fingernails to remove the salt mix.

It was easy to flake off on the flat surfaces but almost impossible around any detail. The problem was the baking soda. Next time I will leave that out or greatly reduce it and go with just salt.

[PuckHog]

Next I added some different shades to the rust spots with sponged on acrylics.

It is time to leave it alone for awhile.

[PuckHog]

It turned out okay thanks to all the people willing to share their techniques on the various forums.

It is so different from my old method of black paint and rust powders......Randy

[PuckHog]

The next time I will airbrush so I could use much thinner coats of paint and maybe go with all acrylics. Really lost some  detail.  Next time will show progress on frame and gears.    Randy

[marc_reusser]

Nice to see you experimenting with the technique.

Not as a knock towards what you have achieved, but just a suggestion, since you seem not completely happy with it...why not just wash of the paint with thinner, and start over. The resin should not be affected.


You are correct in your two assumptions of wherre the problems are, baking soda, and spray can enamel. When I first saw yuor mention of baking soda I thought wow..interesting (I assumed you were using it for a more "scale" HO effect)....but I was wondering how you were going to pull it off  .....I believe the problem with it is that it is too fine, and this is easily covered, sealed with the paint (it also can disolve somewhat this blending with the paint).

I don't necessarily thing that the enamel itself is the problem (though it is not as fine as a good acrylic) but rather the thickness of the application (If you read the posts/SBS by vsuarez666 he too uses enamel...but shoots it in thin coats that arent very "wet").....the salt will also begin to disolve and blend with the paint if you shoot to heavy or wet.

Another thing to consider...especially at the smaller scale, is the amount of water used to attach the salt, rather than being completely soaked and wet, it is probably better to have a damp surface (brush applied)...as again the wetter the more easily the salt will disolve and bleed onto the base color, and then be difficult to remove.


Look forward to your progress.


Marc

[PuckHog]

Marc,  Thanks for the encouragement...and yes I was using that sbs and did think that i had to " scale down" the effects (I believe that his subject was 1/24th)      Oh well, I'll take your advice and try again. it is worthwhile and fun to try something different.  Randy

[PuckHog]

Peeling paint and rust part 2....After stripping the boiler down , I started over.  This time wanted not to lose detail and wanted to add lifted metal ,peeling paint rotted out look.  Followed a wonderful SBS on mig forum by Per Olav Lund where he used very thin foil applied on the surface then carefully peeled portions back.

[PuckHog]

I then added the salt ( without the baking soda)......Randy

[PuckHog]

Still used enamels but thinner coats.....Randy