We had some recent posts showing hand cut M&T joints but as a contrast, here is how I do mine.
First key thing is keep the hand chisels in the drawer - you just don't need them!
Second thing is to prepare all the stock to exact lengths and faces square with the usual sequence of table saw, planer and thicknesser. If you have a hand plane and it is a warm day, use it to prop the workshop door open. You don't need to use it
Lets assume you have the morticer set up with the table so the chisel point is on the centre line of where you want the mortice and lock the axis. Using a piece of scrap do a test cut and mark the chisel to about 1mm deeper than your tenons will be cut.
I like to do the mortices first as that give a reference when it comes to set up the tenon cutting.
You should be able to make out the marked line on the chisel body.
It is simply a case of chopping out the waste to the depth of the line.
My tenons will be 40mm wide 25mm deep and thickness to match the mortice cut by the 1/2" chisel.
I am aiming for a mortice about 0.5mm oversize and 26mm deep. You don't want them so tight that the glue is scraped off when the joint is assembled and neither do you want be hammering them home during dry fitting.
Turning to the tenons. Make sure the mitre gauge on your saw is spot on 90 degrees to the table slot and the blade is dead on parallel with the slot. i.e. as it always should be!
Set the fence so the tooth tips furthest from the fence are 25mm from the fence and lock the fence.
Most normal blades will be ground with alternate top bevel and mine is no different. Looking closely at this photo, you can see the profile of the cut is like a capital M.
The aim should be to slightly undercut the tenon with the shoulder cuts.
Once set up the cuts can be run though very quickly with no marking or measuring.
Now for one on my favourite table saw jigs, The tenon jig. There are a few available in UK and rutlands run an offer a couple of times per year. This is a genuine Delta one I got in the states.
The jig should be set initially so the tenon is just too thick cutting on both faces and then creep up with the adjustment (remember the thickness is reduced by twice the amount you adjust the jig) The correct setting is when the tenon will slide into the mortice freely but with no shake.
Lock all the settings and run all the cheek cuts. Spot on every time again no measurements.
Use similar methods to set up and make the cuts that define the tenon widths.
Offer all the parts up in a dry fit to verify all is well. The joints should all pull up square with out force.
Various parts of this footstool will be handed and so to reduce the stress when it comes to the glue up, I've marked the parts unambiguously in locations that will be obscured in the finished piece.
Thanks for looking
Bob