Blue-ing Photoetch parts.

[nanook177]

Hello all! I'm currently building a 1/350 Constitution Class Refit and am using the Paragrafix photoetch set with it. My question is I'm trying to get a certain effect with the Impulse Engine Grills. I actually like the brass color and feel it would fit in. However, I want it to look like its had to endure incredible heat, just like a rocket engine would. I tried running a test part over a lighter flame but the results were not what I was hoping for. I would appreciate insight or suggestions to be offered. Thank you!

[seam-filler]

There are liquids & pastes available to blue metal (including brass). Look for "Gun Blue" and follow the instructions.

There are other methods (including heat) - watch and clock makers use them a lot. You could try googling forums for advice.

[Rocketeer]

You could try a transparent blue paint, airbrushed on. I believe GarageKit Colors USA has a transparent blue.

Or you could try oil pastels. Tamiya Weathering Masters offers a blue steel color that might be just the ticket.

[Kylwell]

Heat blueing is tricky business. You might be better off trying to paint it.

[Rogviler]

Dykem layout fluid is very good for that. It comes in a spray or you can buy the bottle and airbrush it. Also comes in red, if the need arises.

[seam-filler]

Dykem is a Prussian Blue stain - often known as "engineer's blue" and is used in metalwork to make marking-up easier. It is non-permanent on metal and polishes off very easily. The same cannot be said for skin or clothing and without due care it is a great way of ending up looking like a Smurf. I don't even know if you can varnish over the top of it - it is intended to be temporary. Personally, I wouldn't recommend it for a permanent finish.

Gun Blue, however, does the same thing chemically that the heating method does by thermochemistry - i.e. it produces a thin layer of protective oxidant. Gun Blue on brass can end up quite dark (almost gun-metal dark)...If it works at all. Gun Blue is formulated for steel, not brass so results can be unexpected.

Another thing against trying to use heat on brass is that heated brass turns black, blue-green or even reddish-brown - not blue. It's steels and titanium that turn blue.

I agree with Kylwell that paint is probably your best option. Alclad II "Hot Metal Blue" (ALC 413) is probably the closest to real exhaust bluing. Also available is Tamiya Metallic Blue (acrylic paint X-13, spray TS-19).

[Rogviler]

Dykem is a Prussian Blue stain - often known as "engineer's blue" and is used in metalwork to make marking-up easier. It is non-permanent on metal and polishes off very easily. The same cannot be said for skin or clothing and without due care it is a great way of ending up looking like a Smurf. I don't even know if you can varnish over the top of it - it is intended to be temporary. Personally, I wouldn't recommend it for a permanent finish.

Dykem has been used for years in the modeling and propmaking community for such things as simulating heat discoloration, R2D2's anodized look, et cetera. It's literally just tinted lacquer. Definitely topcoat it, but you probably would anyway.

EDIT: After looking up some things, Dykem is NOT to be confused with "engineer's blue", which is grease based and non-drying. Dykem is like a transparent paint.

[seam-filler]

Thanks for the info. I stand corrected.