Joseph Gwinn wrote:

I'm not sure that this could be the mechanism, because even the larger
bar is well centered between the two rails of the way. Â*Nor can I
imagine the person that allowed the dovetails to become so loose
concerning themselves with something like the hold-down plate.

Two vectors of cutting force during parting off:
1.) pointing vertical downwards from the tip of the blade
2.) pointing horizontal outwards (along the blade) from the in-feed force

If you add the two vectors and the resulting vector is not pointing between
the two rails, the rear will lift. To prevent that, there is a 3rd guide
(rear, downside).


Nick
--
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