Q I've made a custom dash for my project, and I want to hinge a door in the center to cover the A/C controls and the other switches that will mount in the dash. Where can I get some small, hidden hinges that will work for this application? I've looked at piano hinges, which are available in small sizes, but the barrel of the hinge has to be exposed, and I want a cleaner look. Also, do you think its better to weld the top half of the center bump to the dash, or to make it a bolt-on piece?
Frank Millsap - Via the Internet
A There are many ways to hinge a cover or door. You might check out the Soss brand hinge-it's completely hidden, small in section, and relatively easy to mount. They come in a wide range of sizes, and you could probably use the smallest for this application. You can contact them by telephone at 800-922-6957, or check out their website: www.soss.com
The website has an animation that shows how the clever design of the hinge works, and how the mechanism is completely hidden when the door is closed. I've used these hinges for several projects, and they can be the perfect solution in a number of situations.
Another option is to make hinges similar to a car door, but of course you'd have to scale them down appropriately. The primary problem with this style hinge is that the "dogleg" portion of the hinge requires a lot of room, but they work smoothly, and can carry a lot of weight.
If you weld the hump to the existing dash, you'll get massive distortion on the flat areas. For that reason alone, you could make a very good case for making it as a bolt-on item. Also, since the hinged door will have a gap at its edges, the line of separation between the hump and the dash would make a visual continuation of the door gap. I'd probably go with the bolted construction.
You can email your questions to Professor Hammer at firstname.lastname@example.org, or mail to Professor Hammer, c/o CLASSIC TRUCKS Magazine, 774 S. Placentia Ave., Placentia, CA 92870. We'll print your name and city unless you request otherwise. Ron Covell has made many DVDs on metalworking processes, and 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 and fine-quality metalworking tools. Phone 800-747-4631, or 831-768-0705. You can send a request by mail to Covell Creative Metalworking, 106 Airport Boulevard #105, Freedom, CA 95019.
Q Ron, I am having trouble with turning a flange on the curved edge of a panel. I've been using a set of tipping dies in a bead roller, and that works well enough on gentle curve, but tighter curves prove difficult to shrink or stretch (after the flange is turned to nearly 90 degrees) with hand-operated shrinkers or stretchers, since the curved flange will not fit between the jaws of the machine. How do you go about this process?
Andy Perazzo - Via the Internet
A There are several variables here, such as the type of metal, the metal thickness, the width of the flange, and the radius of the curved edge of the panel. Let's take a look at a real world example, where I need to form a 5/16-inch flange on the edge of a 19-gauge steel door skin that has a straight front, back, and bottom, but has a 2-inch radius curve on the lower rear corner.
In this case, I would start tipping the flange with either a bead roller, or with piece of scrap metal with a notch cut in it the depth I want the flange to be, or even with a pair of pliers or Vise-Grips. As you know, the straight sections aren't very difficult, but the metal will start to wrinkle on a radiused corner. After tipping the edge to about 10 or 20 degrees, I'd start working with a hammer and dolly. I'd back the flange up with a heel dolly, holding it so the flat face of the dolly was touching the door skin, but the curved edge of the dolly was positioned right at the base of the tipped flange. Now, I'd slowly start hammering on the flange, slowly increasing its angle, working back and forth around the radiused edge. The metal in the flange will tend to form more ruffles, but by carefully hammering off-dolly, they can probably be worked out completely.
There are limitations on what you can do with this process-for example, it won't work with a flange 1-inch wide on a 2-inch radius corner, or with a 5/16-inch flange on a corner with only a 1/4-inch radius. In these situations you will probably need to use heat to help shrink the ruffles out, or you may need to trim the flange width down smaller in these areas to make it possible. If you look at the door skins of production trucks, the width of the hemmed edge is often decreased in the difficult areas for this very reason.
Let me know if you need more pointers on this process-I've just hit the high points, assuming that you'll probably figure out the rest with a little practice!
A Call To Readers For Clever Tools And Fixtures:Classic truck builders often design and make some very imaginative tools and fixture to help build their projects. If you have built or modified a tool or fixture that you think might be helpful to other builders, send a photo and description to Ron Covell (contact information to the left). This could be for bodywork, chassis work, engine work, or any other aspect of truck building. I'll be eager to see your ideas, and we may run some of the best ideas in future "Professor Hammer" columns, so our readers can benefit from your creativity!