The lower edge of the patch piece, which is non-existent on the bed as of now, will span from the rounded part of the bedrail down to the side pillar. In order to make things sharp and accurate Sam uses a straightedge to make his mark from corner to corner. | 
Since the bed has no metal where the lower edge of the patch piece will eventually sit, part of this cap will be unsupported and unwelded. For that reason a small amount of extra material will be incorporated, which will fold over the lower edge and create a much stronger doubled edge. Sam traces a line just beneath the lower edge--the metal between the two lines is what will be folded over. | 
A Beverly Shear was used to cut the patch piece out. Because Sam traced around the edge of the bed cap he cut on the inside edge of his line. If a Beverly Shear is out of the cards, a pair of tin snips works just fine. |
To create the fold, the piece was put in a vise and bent over. Once the limits of the vise were met Sam just held it by hand and beat it the rest of the way over. | 
There's a small area that can't be cut until the fold is made, which is just past the fold mark. Once the fold was in place Sam went forward with cutting the piece of metal out. | 
Because the piece of steel was scrap metal lying around the shop, it needed to be ground clean before the welding could start--in order to make sure a solid and contaminant-free bond will occur. |
Next, Sam ground the edge of the bed side with an air grinder, outfitted with a 36-grit disc, to prepare the bed for welding. | 
Before anything was set in stone, Sam made sure the cap fit perfectly. In this case, things were dead on--if they hadn't been, a slight trim here and there with the shear would have done the job. | |