[john lucas]

It's been so long since I had my shopsmith I can't remember the tool post size of even if after market tool posts will fit. I do 90 percent of my bowl turning with a regular flat tool rest. Just adjust it so it will reach inside the bowl. I have 4 specially made bowl turning tool rests but just never think to use them because my normal rest will reach in far enough that there isn't much tool overhang so I go ahead and use it.
Shopsmith does make a bowl tool rest. http://www.shopsmith.com/ownersite/catalog/l_sshape.htm
My favorite aftermarket tool rest is the Robust. Again I use the straight one for most bowls but he makes several excellent bowl rests.
http://www.turnrobust.com/Robust_Tool_Rests.html