A good friend told me that another guy dimensioned some HD framing lumber in his shop and "the sap in the wood gummed up the cutters and caused the wood to have burn marks, had to remove gum with Simple Green, took a while". I've never heard of this or experienced it; I've dimensioned Doug Fir and SYP at my friends shop no problem. My friend has high-end equipment with carbide cutters. I suspect the other guy doesn't know how to buy lumber and got some with lots of sap. Assuming you sort through the pile and buy good lumber with no visible sap or pitch pockets, is it going to gum up the cutters? I'm in Colorado, most of our framing lumber is Doug Fir.