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Old 08-07-2009, 01:46 AM
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How to Make Aluminum Clad Card Stock

How to Make Aluminum Clad Card Stock (Part I)

By Gil Russell

Edited by Leif Ohlsson

7 August 2009


I wonder how many times modelers have experimented with ordinary aluminum foil in attempts to recreate a natural aluminum finish on their models. One method, developed for plastic models, applies aluminum foil in a manner similar to the method used for gold leaf. The underlying surface has to include all the desired detail before the foil is applied. Thinking about applying this to card stock took me around the block several times resulting in several shattered preconceived notions along the way. The strange part of this story is that the solution shown here is non toxic and uses commonly available materials.

A large variety of glues capable of bonding aluminum to paper were tried. One theory (a mishap of preconceived notions) was that to maintain flat unwrinkled paper a non-water based glue would be required. The problem with non-water based glues is that they generally require a fairly aromatic thinning agent. A goal was set early on to minimize the exposure to volatile organic solvents (VOC’s). The VOC glue tests produced some interesting results but had to be eliminated from consideration due to their toxicity (3M spray adhesive produced an easy to layup assembly but failed to yield a smooth mirror like surface).

Smoothing Aluminum Foil
The first small breakthrough was discovering a method to flatten the aluminum foil in preparation for bonding it to the card stock. The trick is to mist a pane of glass with a water spray before carefully applying and smoothing out a sheet of aluminum foil onto the glass (shiny side down). The water adheres the foil tightly to the glass pane and in effect clamps it to the glass.



Figure
1 Water Misted Glass Pane

Do not use the cutting edge on the foil box. It only deforms the foil making flattening more difficult. Use scissors instead.

Aluminum foil thicknesses vary from manufacturer to manufacturer and have a direct affect on the use as described here. Reynolds Wrap Heavy Duty Aluminum Foil is used exclusively in this tutorial. I found it to be consistently thicker than other brands. Use heavy duty or extra heavy duty foil for models requiring moderate compound curves.



Figure
2 Laying Out the Aluminum Foil

Use a squeegee to smooth the aluminum to a perfectly flat sheet on top of the glass. Water sprayed on the aluminum surface aids the squeegee smoothing action.




Figure
3 Smoothing the Foil



Figure
4 Smoothed Aluminum Foil

Preparing the Aluminum for Bonding
The strength of the paper to aluminum bond depends to a great extent on the aluminum foil’s surface condition. The foil has a minute amount of residual manufacturing lubricant left on its surface (yes it’s edible). It will interfere with the bond if it’s not removed.

Use a 3M style scrub pad with window cleaner sprayed on the aluminum. Scrub the aluminum surface using a circular motion to scour the entire surface well.



Figure
5 Cleaning the Aluminum



Figure
6 Removing Cleaning Residue

Clean the scrubbed aluminum surface with an absorbent sponge. Mist the surface with a slight amount of water and wipe with a paper towel. Spread a small amount of either isopropyl or ethanol alcohol on the surface. Finish by drying the surface with a paper towel.



Figure
7 Final Cleaning with Alcohol



Figure
8 Aluminum Ready for Bonding

(Continued in Part II)
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