Whats a good substitute for Burnt Iron?

Perhaps a rust color, or even leather?   A mid-brown, dry brushed with steel, or similar, might work as well.

Or maybe I'm on the wrong tangent color-wise.  Are we talking a gray shade since you mentioned "engine"?

Its the back of the engine where it would attach to the firewall, so its whatever is behind the actual engine, maybe its the exhaust?

What paints are you using?

I'd either use Tamiya or Model Master. I went to the store and couldn't find a bottle that said "Burnt Iron" so I'm guessing I will have to mix my own. Any suggestions?

Model Master Metalizer laquer had a burnt iron in its line.

I didnt see it at hobby lobby, I think I'm going to skip the engine for now and work on the fuselage and wings. I can make another run somewhere else tomorrow.

Perfect.  I only ever paint with Tamiya paints.  What I would suggest is to start with painting everything Flat Black.  Let it set up and then move on to something like a Flat RedBrown or a Nato Brown.  You don't need to completely cover the black, but I would mostly cover it.  Thin your paints down so you can see the change happen at a rate you can detect. =]  Sometimes I will even take a little Flat Yellow with some Flat RedBrown and mix it...not thoroughly...just a couple of swirls (keeping more yellow), thin it down, and drop a few tactfully placed swipes to show some variation in the rusting.  Depending on the fuel used, with leaded fuels you could thin out some Light Grey with some Flat White and thinly drag your brush along the exiting edge of exhaust.

That works for me pretty well.  =]

On my exhausts, I use XF-64 Red Brown over XF-1 Flat Black then a slight dry brushing with silver.

Joe

Thanks guys!

Model masters acrylic #4676 is "Jet Exhaust"

I used a "recipe" for a  while with Tamiya paint: 1 part flat black. 1 part gun metal. 2 parts red brown.

AH so many options! I don't think it will be seen so I'll just do something close to it using what one of you said.

I often use a flat gray with drybrushed Testors Steel or some other aluminum or silver color drybrushed on.  For burnt steel I also then drybrush on some flat medium to dark brown.  Just a thin, translucent shading, hence use of drybrushing.  Like washes, a little goes a long way.

I believe the Model Master metaliizer  burnt iron is mostly brown, perhaps with a bit of aluminum mixed in.  I used it on an F-15 model for the exhaust nozzles years ago, and it looks great.  It's probably still available today.

I believe Gunze/Mr. Hobby carries Burnt Iron.