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07-12-2011, 06:30 PM
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From the September, 2011 issue of Classic Trucks / By Ron Covell
You can email your questions to Professor Hammer at covell@cruzio.com (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 Ron Covell Creative Metalworking Workshops (http://www.covell.biz), or call for a current schedule of workshops and their free catalog of DVDs on welding and metalworking. 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: I’m looking for a welding tabletop that will be able to take repeated heating without distortion. I only need a piece 18-inches square. The local metal distributor has three types of plate: 1045 hot rolled, A-36 hot rolled, and Grade 50 hot rolled. It could be any thickness, but I was figuring on ¾-inch. What suggestion do you have for the type of metal I should use?
Mark Wilkinson
Via the Internet
A: Any of the steel alloys you’ve listed will work fine. A-36 is common mild steel, and the 1045 has a little more carbon, putting it in the realm of medium carbon steel. The 1045 steel will have a slightly higher tensile strength than the A-36, but that’s not really needed for a welding tabletop. Grade 50 is a high-strength, low-alloy structural steel, but again, with a welding table, all you are looking for is flatness, heat absorption, and resistance to deflection after many rounds of heating and cooling.
If it is only going to be 18-inches square, ¾-inch thickness should be adequate, but thicker is always better! If you bump it up to 1-inch thickness, it will weigh (and cost) 25 percent more, but it will be more than twice as resistant to deflection!
Hot-rolled steel is the norm for heavy plate, and it has a carbon scale on the surface that is very difficult to remove–the scale is actually harder than the metal underneath! If you can get P&O (Pickled and Oiled) steel, that will save you from having to grind the scale off the surface! Some people have their tabletops Blanchard-ground, which is not extremely expensive. This not only removes the scale, it leaves a precision, absolutely flat surface that can be helpful for straightening parts or for fixturing high-precision assemblies.
Q:I saw your great column in the June 2011 issue of Classic Trucks, where you mentioned stripping and polishing an aluminum grille.
I found that a mixture of lye and water will nicely remove the anodized surface. The stronger you make it, the faster it works, but be careful! The lye must be used in a plastic container. For very large parts, (my car had 6-foot-long rocker trim pieces) a wood box with a plastic liner works great. After the anodizing is removed, you can easily pound out the dents, sand off the road rash and other damage with progressively finer sandpaper, polish, and have a show-quality piece. The aluminum is easy to repolish whenever it starts to get dull.
Bill Gildersleeve
Paulden, AZ
Via the Internet
A: Thank you so much for your feedback! I didn’t know that stripping anodized parts was something a do-it-yourselfer could do, and your report that it’s easy to repolish aluminum trim after it starts to dull is good to hear! I’m always eager to learn as much as I can about metalworking of all sorts, and I’m sure this information will benefit many builders of classic trucks!
Q: I have a ’57 Ford truck and I want to stretch the cab. I plan to cut across the roof and floor at the rear doorjamb, and move the rear of the cab back about 14 inches. I have a good idea about how to proceed with this, but I want to add small quarter-windows behind the window in the door. Forming metal into the shapes needed to match the door reveal around the windows has me stumped. How would you form these parts?
Bill Swenson
Via the Internet
A: Well, it’s possible to make pretty much any shape you want from metal, but in this case, you might be better off buying some junk doors that have a good top portion. You could “slice and dice” the area around the door glass to make it match the proportions of your stretched cab. Not only would this eliminate a lot of fancy metal forming, it would ensure that the reveals around your quarter-windows have exactly the same profiles that the door has.
You should be able to find plenty of doors with collision or rust damage on the bottom, which reduces their value considerably. Often, the tops of these doors are in perfect shape! CT



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