How do I bring out panel lines after spraying the aluminum finish?
Try washes.
There are several ways to do this. The easiest would be a sludge wash. In brief, get some chalk pastels and scrape them into a powder with an Exacto knife. Add to a cup with water and a little dishwashing liquid. I’ve used it and it works great, especially on natural metal finishes. Heres a great tutorial on how to use it.
http://www.arcair.com/tnt1/001-100/TNT026-Chalk-Washes/00.shtm
Another option, which I use often, is Windsor Netwon “Cottman” Acylics, mixed with water. They can be found at Hobby Lobby and the like but are expensive though. I did however just discover the clay based Flory Wash, which I bought here (I use the Dark Dirt).
http://store.spruebrothers.com/product_p/prodw.htm
Its also somewhat expensive but does come in several shades and It seems one bottle will last a long time.
Hope this helps and good luck,
Joe
Thank you very much for this excellent advice and assistance. Now I have somewhere to start. Thanks again.