The Powermatic 719T http://www.powermatic.com/Products.aspx?Part 91264K&cat=P120 tilts the table to the left, so that you can cut a mortise like this (side view): ______________ __________ / / --------------------------------------------
The General International 75-075 http://www.general.ca/products/1_general/75_mortiser/75-075.html tilts the head to the right, so you can cut the same kind of mortise.
Likewise the Grizzly G0448 http://grizzly.com/products/Heavy-Duty-Mortiser-With-Stand/G0448 except that the head tilts left instead of right.
But what in the world is the use of cutting a mortise like that? I don't get it.
I understand that for chairs in particular, it's desirable to cut angled mortises in the legs, because chairs typically are wider in front than in back -- but these mortisers won't do that type of angled mortise. Angled mortises in chair legs need to look like these
and there simply isn't a way to cut those with these machines.
Grizzly even says "Simple adjustments allow the head to tilt up to 30? left or right, and the fence also pivots up to 30?, providing just about any combination of angles." Just about any combination of angles *except* those you'd need to make a chair, which seems to me to be the *main reason* you'd want to cut angled mortises.
I don't get it. What am I missing here? Why would you want to tilt the head, or the table, at an angle parallel to the *long* axis of what you're mortising? And what's the point of Grizzly's pivoting table? I just can't wrap my head around the purpose of cutting mortises at these angles. Or how I could use one of these machines to make a chair.