Hi, Working on a 1940's believe post war sprint car cowl. Looking for information on how I can determine what series the Aluminum might be and what series I can use to repair it? Also what series Aluminum rod to repair it. Thanks.
If it has a lot of shape, it is probably 3003 alloy, or something close. I was talking to a friend and we had a discussion, about how metal shapers used to shear strips, of the same metal they were working with for filler rod. When 1100 series rod came out, that is what they went to.
Cutting strips of base metal for filler rod is a trick for welding parts that will eventually be polished. This way there will be no color change when finished 1100 rod is mostly used for gas welding any of the weldable series of aluminum alloys. This rod is very formable and resists cracking when additional forming is required
Will do later tonight. Looking at it, she was banged around for years. See yellow paint as first color then a blue and finally white. Came from an estate sale in Conn. Looking on the underside it was hammered into shape. Fitting it to a nose from another sprinter. Thanks
We had a machine (a arc/spark optical emission spectrometry (OES) analyzer) .in our metallurgy class that would draw an arc on basically any metal material, and would give you a printout of the makeup, which would basically tell you the exact grade of material it was. I would assume any good metallurgy lab has one these days if you really wanted to get exact.
May be mistaken but I think 5052 0 Temper (fully annealed) is used a lo for metal shaping. I know 5052 is used a lot when multiple bends/brakes are required in a sheet.
That is really the best way to really determine the specific alloy. Also that will help to know which filler to use. A higher end recycling center may have one, using it to sort aluminum. Or a local college materials dept might be helpful as another alternative. The common Al filler rod is alloy 4043. I second the idea to use some of the parent metal if you can as a good source. All this assumes the alloy used originally is one of the weldable grades, not all Al alloys are weldable.
Can't tell exactly what you want to repair there but it looks like that cowl does have some history. As has been mentioned you could have a sample analyzed to determine the chemical composition and narrow the down which alloy. This would be some expense and probably not worth the time. If your dead set on keeping it for historical reasons then find someone that has the skills and equipment (if you don't) to restore it. You could make patterns from it or even a wooden buck and fabricate a new one from 5052 using the same thickness. It is possible someone made that from 6061 but 6061 is much more difficult to form and shape. You can TIG weld either with 4043 rod.
The reality is... if you intend to paint the car, use whatever alloy you want. If there is heavy forming to be done with hand tools, use 3003. 5052 can be used too, but will be considerably more effort. If the panel is structural or will be prone to getting leaned on, use 5052. 3003 has to be really thick to be durable. 3003, 5052, and 6061 (as well as others) can be TIG welded together with 4043 filler rod. 1100 rod can also be used with TIG or gas welding if additional forming is required after welding. TIG welding will leave a “hard” weld, and so will tend to crack if not annealed prior to additional forming
Cowl has quite of bit of bondo on her. From inside you can see where it was beat into shape so outside had to have a cover of bondo over it. Someone ripped out the steel rod shaping the lip and there is a big patch on the inside right side where it looks like something poked thru it. They pop riveted it in! Want to save her not make a new one. Think I will strip layers of paint to see what is underneath. Any best ways to do this? Is there a way to tell if it was gas brazed or tigged. When I restored my midget in the 1980's I found it hard to determine my tig welds from the early gas welded panels . That race car was built in the late 1930's. Thanks
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