You can email your questions to Professor Hammer at covell@cruzio.com, or mail to Professor Hammer, c/o Classic Trucks Magazine, 1733 Alton Pkwy., Irvine, CA 92606. You’ll receive a personal reply! We’ll print your name and city unless you request otherwise. Ron Covell has made many DVDs on metalworking processes, and he offers an ongoing series of workshops across the nation covering all aspects of metalworking. Check them out online at www.covell.biz, or call for a current schedule of workshops and their free catalog of DVDs. Phone 800-747-4631, or 831-768-0705. You can send a request by mail to: Covell Creative Metalworking, 106 Airport Blvd. #105, Freedom, CA 95019.

Q. My vehicle is a ’64 Ford F-100. I read the question on stainless steel grille repair you covered in the Nov. ’10 issue of Classic Trucks. I have an aluminum grille needing a minor fix. Should I proceed in the same way as you described for stainless steel? The area is a straight bar that has been slightly bent. It’s too short for me to bend back with my hands, and I was wondering about heating it to bend it back straight.

Also, I discovered the metal just above the rain gutters is rotting. It’s on the flat area above the doors,before the roofline starts. The rotting portion is as wide as the top of the door and about 2 inches tall. The rain gutter itself appears to be rot free. I have access to a small 110V MIG welder, but few metal-shaping skills. What is the best way to replace the metal in these areas? Should I remove the rain gutter and replace it, or just cut out the area that’s rotted? The area isn’t completely flat; it has a very slight curve to it.
Thank you in advance for your input and expertise!
Sal Lombardo
Sacramento, CA
Via the Internet

A. With any aluminum grille, I’d try straightening it without the use of heat first. Heat is big medicine, and if you don’t have a finely tuned feel for the work, you can easily ruin the part! The same techniques that work with stainless (or mild steel) will work with aluminum, but since it’s a softer metal, you have to be gentler with it. If you simply can’t get all of the damage out at room temperature, heat might be an option, but you have to be very careful, since aluminum melts around 1,200 degrees Fahrenheit (about half the temperature as steel), and it doesn’t give you any warning before it melts!

Also, most aluminum trim on cars and trucks is bright anodized to prevent corrosion, and to give it a shiny, chrome-like appearance. Unfortunately, heat will damage the anodized surface, and it’s really not feasible to reanodize the grille. You could certainly paint the grille after straightening, and some of the new highly reflective chrome-like paints are pretty impressive.
If you are sure that the rain gutter is not rusted, it’s a pretty simple job to replace the metal above it. You can simply make a paper pattern for the patch you’ll need, and cut a piece of metal to match the pattern. Since the patch needs such a small amount of curvature, you can shape it by hammering gently against the inside of the panel, backing it up with a smooth block of wood such as a common construction 2x4. Once the patch is shaped, hold it into place against the rusted area, scribe around the edge, and cut the rusted area out. Then, the new patch can be welded into place.
I recommend cleaning all the paint off the gutter and inspecting it very carefully, since it’s not uncommon for the gutter to start rusting before anything else, and if the gutter needs to be replaced, this is definitely the time! Replacing the gutter is a much larger job because of the way the roof skin overlaps it and the way it ties into the upper doorjamb, but you only want to do this job once, so be sure that you replace all the metal that has been affected by rust--if you leave even a trace, it will bite you in the butt before long!

When you are making templates for aluminum or steel sheet, what type of cardboard do you use and where do you get it? In other words, what type of cardboard best mimics the metal characteristics?
John Machado
Via the Internet

A. I use a material called chip board for most of my patterns. It’s very much like the heavy paper they use to make cereal boxes. It’s available from many sources; the last couple of batches I got were from a large commercial printing company. I don’t think they do much printing on chip board, but when they fill up a large box with printed forms they use the chip board to separate layers. It’s thin enough to cut easily with scissors, but heavy enough to hold its shape pretty well. I don’t like to use corrugated cardboard, since it doesn’t bend smoothly, and it’s difficult to cut with a clean edge. CT