I saw large logs in half with a chainsaw mill. 52" width of cut. Have Alaskan and Sperber mills. Both are modified to have the option of deeper than normal cuts. The Alaskan is a 56", and I bought two uprights from them with 36" long vertical bars. Eric at Granberg sold these to me. The Sperber has round aluminum uprights which are end drilled to mount at the top. I made 3 sets of auxiliary uprights from aluminum of the same diameter, which I end-drilled on the lathe, tapped, and inserted a threaded stud of the same diameter/thread in order to make extensions which I add to the top of the mill's uprights to extend the depth of cut. Have used it to quarter very large logs too big for the wood-mizer to quarter, under 4' diameter.