welding c4 rear cross brace
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From: Lanexa Virginia
welding c4 rear cross brace
I am narrowing the rear cross brace in a project build using c4 parts . what grade of aluminum is the cross brace made from . I have searched the forum for this info and came up nada. can someone help? I do not want to use the wrong welding rod .I'm thinking it is 6061 .if so 4043 rod should be ok . just not sure ...
Melting Slicks
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From: Mystic CT
I would very sincerly doubt if it is made out of 6061 that is usually found as an extrusion or rolled plate and not very cost effective to do the batwing. If I had to make an educated guess it would be either 355 or 356 the same stuff GM does cylinder heads and other parts. It is easy to weld with the rod you selected just know it will have the mechanical propertirs of styrofoam when you are done. BTW the rod is not the problem you will take out the heat trad from the weld zone and that is the problem.
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From: Indianapolis IN
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From: Lanexa Virginia
Yeah dont even try to weld it without preheating you won't like the results.Another tip remove all the rough surface from the casting with a proper sanding wheel and then clean everything realy good with alcahol . then preheat, then just before you weld wire brush it with a ss/steel brush. if you do everything this way you will have less problems with your weld
Melting Slicks
Joined: Dec 2008
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From: Mystic CT
I hate to say it but it is still peanut butter as far as strength goes. Something can look good and be useless all at the same time. If this is for a low hp light street car it might be ok but is for a car the weight of a Corvette and over 350 ft lbs of torque I would make the next project a cage for the crash victim to sit in.
Dave
Dave
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From: Lanexa Virginia
Dave , I respect your input as it is not as strong as the oem part was as built . However in the hot rod industry many aluminum parts mave been welded and most do a good job. In this case what would you have done?
Drifting
Joined: Aug 2010
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From: Montgomery Texas
I weld alum all the time because of my other high dollar passion. ( airboats ) Once you weld and area it is a given it will break on either side of the weld down the road. The best luck I have is weleding and area, then smooth it out and plate it over and weld the plate. I heat the whole area first, stitch the welds to keep heat down and make sure everything is very clean. Your wire brush or wheel must be stainless steel and if it is not new it better have never been used on carbon steel.
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From: Lanexa Virginia
After hearing all the replys I think I will add a 6061 t6 x 1/4 brace and fit it between the rear cover and the housing in the shape of the brace and extend it out to the side mounts and bolt it with the outer mounts through the outer bushings and use a longer gr-8 bolts . This should add extra support to the welded brace just incase it does crack .. ..Thanks to all for your comments. John / johnrodz
Melting Slicks
Joined: Dec 2008
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From: Mystic CT
After hearing all the replys I think I will add a 6061 t6 x 1/4 brace and fit it between the rear cover and the housing in the shape of the brace and extend it out to the side mounts and bolt it with the outer mounts through the outer bushings and use a longer gr-8 bolts . This should add extra support to the welded brace just incase it does crack .. ..Thanks to all for your comments. John / johnrodz
Dave
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From: Lanexa Virginia
well if welding the ends back on the narrowed version wekened it then won't more welding down the beams weken it even more?at least right now it just welded on the two ends where there is somewhat less tork out there than in close to the center . any way I thank everyone for there input.. johnrodz
