eggshell/foil technique (replicating discoloured metal)

TB2 · Post by **TB2** » Sun Apr 16, 2006 5:42 pm

Does anyone know how to discolour foil using crushed eggshells? It's a method used to replicate burnished or discoloured metal on things such as aircraft exhaust cans. From what I understand, regular cooking foil is placed in a pot of boiling water with crushed egg shells, the time it's left in affects the look. I tried it myself but got spotty results. Not sure how many crushed shells to use, how much water etc. Any advice?

Lt. Z0mBe · Post by **Lt. Z0mBe** » Tue Apr 18, 2006 12:35 am

Are you using tap water or distilled water? DIstilled water is not going to have all the chlorine and lime in it. I'm wondering if that might be the cause of your variations from the book writers'. Who knows what kind of mineral content is in their water?

I hope this helps.

Kenny

Kylwell · Post by **Kylwell** » Tue Apr 18, 2006 9:59 am

IIRC it's the sulfer content present in the eggshells (migrates out from the core when boiled). Tap water with it's questionable chemical content probably won't help.

dhanners · Post by **dhanners** » Tue Apr 18, 2006 5:20 pm

I've never tried it with crushed eggshells. I've always just used whole eggs, and you go about it as if you were fixing hard-boiled eggs. Stick sections of foil in the water, stick an egg or three in there and turn on the heat. Eventually, the water will boil and after a few minutes, you'll have discolored foil.

A couple of things to note.... Experiment to see how long it takes to get various levels of discoloration. And make sure you have tongs or forceps to take the foil out of the water.

Also, keep in mind you may have to do several sheets before you get the shade you want or enough foil to cover the area you want to cover. The discoloration isn't always even because the movement of the eggs in the boiling water usually causes the egg(s) to bump against the foil, causing creases. While the creases can be smoothed out later, the discoloration may be lighter or darker along the crease, depending upon which side you're looking at.

Augustus · Post by **Augustus** » Tue Apr 18, 2006 6:07 pm

You don't eat the eggs though do you?

Interesting topic as I have never heard this process before.

Antenociti · Post by **Antenociti** » Tue Apr 18, 2006 7:25 pm

Blimmey - thats a new one!

I just use a shade of Alclad 2... but the eggy-method sounds more fun.

TB2 · Post by **TB2** » Wed Apr 19, 2006 9:10 am

Thanks for the input guys. Suggestions on what adhesive to use to attach the foil?

(Who thinks of this stuff anyway? What's the thought process?
"Hmm...exhaust discolouration.....EGGS...yeah, that'll do it!)

Lt. Z0mBe · Post by **Lt. Z0mBe** » Wed Apr 19, 2006 11:46 pm

TB2 wrote:Thanks for the input guys. Suggestions on what adhesive to use to attach the foil?

(Who thinks of this stuff anyway? What's the thought process?
"Hmm...exhaust discolouration.....EGGS...yeah, that'll do it!)

White glue, slightly diluted.

I hope this helps.

Kenny

starmanmm · Post by **starmanmm** » Fri Apr 21, 2006 8:49 am

There is a glue specifically for foil that is found in the hobby stores. Forget the name but it is out there for I have used it.

Kylwell · Post by **Kylwell** » Fri Apr 21, 2006 8:53 am

Or Elmer's Carpenders glue is what I've been recomended to use. It's the yellowish stuff. Tackier and a better grip. More horse I suspect.

Are you talking about 'size' Starmanmm?

dhanners · Post by **dhanners** » Mon May 01, 2006 4:13 pm

You can use thinned rubber cement to affix it, but the best stuff to use is Microscale (or whatever the heck the company is named now) "Metal Foil Adhesive." Brush it on the foil, let it dry and stick it on.

You can find the adhesive at your local hobby shop, usually in the same Microscale rack where they display the decal solvents, etc.

And, yes, you can eat the eggs, provided you let them boil longer than the foil.