The large smooth, flat areas on the outside face of the cutting whee,l had, when new, beads of hard surface weld running crossways. The beads covered all that smooth surface you see between the outside edge teeth. I had a welding shop do mine and they just used approx. the same number of passes on each area around the outside edge of the wheel. The Carlton factory service dept told me it is not necessary to rebalance the wheel.
Also, you will have to take several of the pockets off before you do the welding, or you will likely accidentally weld them to the wheel. You can see, if they were not so worn down, they would extend right up to where the weld is to be applied.
If you can get a good photo of a wheel on a new machine, you can see where the hard surface needs to go.