Originally Posted by
Isaac Smith
I make my saws with slotted spines. I can't speak for other makers, but on the saws I build, something went seriously wrong if the blade needs to be adjusted in the slot.
First, a little background on how I build my saws. Before the blade is installed in the spine, I squeeze the slot shut. When I pound the spine into place, the blade bottoms out in the slot, and is held there by friction. A lot of friction. The fit is, for all practical purposes, permanent. I have occasionally needed to remove the blade from the spine; in about a third of these instances, the plate is sacrificed in the violent struggle for liberation.
Before a saw leaves my shop, I check the blade against a surface plate to ensure that it is planar. If the blade, at some point in the future, becomes non-planar, it is due to one of three causes: a twist or bend in the spine, or a bent/kinked plate. The first two can be remedied by straightening the spine, while the third cause probably requires that the plate be replaced.