Q. I want to punch a lot of louvers in my current street rod project. There is nobody in my area with a louver press, so I’m considering building one myself. I think I can handle making the C-shaped frame, and working out the hydraulics, but I’m stumped when it comes to making the dies. Do you know of any companies that make dies for punching louvers? I’d be especially interested in any unusual shapes that may be available.
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A. You are correct that the dies for a louver press are pretty challenging to make. The cutting surfaces should be made from tool steel, and they need to be precisely made (and razor sharp) to work well. They work best if they have a spring-loaded stripper bar, which holds the metal flat as it’s being punched, and forces the freshly punched louver off of the die.
There are two companies that I know of that make louver dies. One is Mittler Brothers (www.mittlerbros.com). They make several different sizes of louver dies, in a couple of different styles. Many people prefer the look of their “standard” dies for automotive work, and they have these in 1-, 2-, 3-, 4-, and 5-inch sizes. Their other “domed” style comes in 3- and 4-inch sizes. They also have a small, bench-mounted press frame that will accept these dies. This frame would be good for small panels, but wouldn’t work for a fullsized hood, or other large body panel.
They stock many of the additional components you’ll need, too, including the hydraulic ram, and an air-over-hydraulic pump. They also have plans for a 48-inch throat depth frame, which should accommodate any automotive panel.
Just recently, at a West Coast Metal Meet, I saw a completely unique louver die, with a beautiful, rounded shape. It’s made by Bonneville Bad Boys (Penn Valley, California; www.bonnevillebadboys.com). There are two different profiles available, and they are unlike any louvers I’ve seen before. The accompanying picture shows these dies and the louvers they make. I think they are pretty darned cool.
Either of these suppliers should be able to answer any questions you may have, and once you’ve built your machine, I’m sure it wouldn’t be hard to generate a little extra cash by punching louvers for other people, if you are so inclined.
Q. I welded my rear fenders to my body, and now I want to use body solder to fill in the gaps. I completed the driver side, and now I’m working on the passenger side. There is an area that has some deep rust, but I can’t cut it out without great difficulty! I’ve tried to prep the metal by using soldering paste and scrubbing it, but the solder won’t stick. What do you suggest to get the metal ready for the solder paste? I know I can use Bondo as a last resort, but I’d much prefer using solder.
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A. The metal has to be “squeaky clean” for the tinning material or the solder to stick. If you can’t get it clean enough by sanding, try a 3M Clean and Strip disc. These discs can get to the bottom of small rust pits.
For rusted areas that are deeply pitted, you may have to use sandblasting to remove every last trace of rust. You’ll need to lightly sand the areas after sandblasting, to smooth the metal and get a clean, shiny surface.
There are many ways to tin the base metal; tinning salts, acid and solder, tinning butter, and so on. All of these can work well, so use the process that gives you the best results. If you overheat the base metal it forms an oxide layer on the surface, which the solder won’t stick to. Therefore, be sure to keep the heat low, and if you see any trace of color develop on the base metal, you’ll need to let it cool, sand all the color off, and start again.
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