Box Rear Upper Control Arms

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Boxing Rear Upper Control Arms 0001A Ok, the idea is to take this stock GM A-Body 10-Bolt rear end control arm and Box it, and convert it into a 12-bolt rear end arm. A 12-bolt rear end arm can be used on 10-bolt rear ends but 10-bolt rear end control arms can not the used on a 12-bolt rear end. For a discussion on this topic see this link (click this text).
 Boxing Rear Upper Control Arms 0001B First step has been accomplished. The arm has been cleaned up and the bushing has been removed. To see how to remove bushings see this link (click this text).
 Boxing Rear Upper Control Arms 0001c Now we need to create a template of the piece of metal we will use to create the bottom plate to box the rear upper control arm. I placed the arm on a piece of poster board and traced the bottom outline. Then I cut that out and taped it to the arm and traced the rest of the piece needed. I cut it out and did a trial fit.
Boxing Rear Upper Control Arms 0012 This is just another view showing the end piece.
Boxing Rear Upper Control Arms 0013 This is what I ended up with. Now the trick is to turn it into a piece of metal. I happen to have a freind who has a Plasma cutting X Y plotter.
 Boxing Rear Upper Control Arms 0015 So these are the pieces I ended up with. You could do the above steps yourself and save the dollars.
 Boxing Rear Upper Control Arms 0017 Next step is to carefully bend the flat pieces so they conform to the arm. You want a nice fit so the pieces lay on the arm with no gaps. Note the pieces are slightly smaller than the arm. This leaves room to build up so weld bead so the weld is nice and strong.
 Boxing Rear Upper Control Arms 0018 Just another view showing the end and how nicely the piece has been bent to fit the arm leaving room to build some weld bead.
 Boxing Rear Upper Control Arms 0019 Ok, now we are getting to the good part. Clamp the bottom in place to insure a tight fit, and that it does not move around on you.
Boxing Rear Upper Control Arms 0020 Do not try and run a bead all the way around the outside of your bottom piece. Make small spot welds skipping around so you do not warp the metal.  
Boxing Rear Upper Control Arms 0021 Now you can remove the clamps to give yourself good access  to finish your welding.
Boxing Rear Upper Control Arms 0022 Just another view showing the end.
 Boxing Rear Upper Control Arms 0023 Now make small “stitch” welds in alternating positions to avoid any warping of the arm or bottom piece. You can also no see why the bottom piece is made slightly smaller then needed so that you can build a nice weld bead for strength. You need the extra weld bead when it comes time to grind it smooth.
 Boxing Rear Upper Control Arms 0024 Welding is done and the beads have been ground smooth. The arm now has the appearance of being all one piece. Bottom view.
Boxing Rear Upper Control Arms 0025 Top view.
Boxing Rear Upper Control Arms 0026 Finial cleaning and now ready for powder coating.
 Boxing Rear Upper Control Arms 0029 My new Powder Coat gun. It is a full 100,000 volt gun.
 Boxing Rear Upper Control Arms 0029a My oven to bake the parts in.
 Boxing Rear Upper Control Arms 0030 All done, ready to cool off.

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