...to end up with stiles and rails like so. Made the classic greenhorn error and used a fence face that was too deep for the narrower stiles; luckily t'was a simple matter to slip the 044 cutter into the 043 and complete the job. But still "d'oh".
Then selecting the only 1/4" mortise chisel (with a handle) that actually fitted the groove ploughed by the alleged 1/4" cutter. Viz: a Marples sash mortise chisel...
...successfully whacked out half the mortises. Well as far as I know they're successful; things going as they are, anything could reveal itself if I ever reach the tenon-fitting stage.
a) I don't know me own strength, guv.
b) The slight pitting on this pre-owned chisel was more serious than it appeared and weakened it slightly.
c) It hit a rather harder area of wood - possibly corroborated by the presence of a chip in the edge which wasn't there before the fatal blow.
d) Combination of two or more of the above.
I've not checked to see if it's still tempered beyond the break point (might also be a factor?) so I don't know if I can just grind a fresh bevel and carry on. Failing that I have a socket chisel of the right width (really don't want to complicate things by having different width mortises in different places, or spend my time trying to enlarge the finished ones). Only problem is it needs a handle, as do its two socketed companions, and I really didn't intend to get into a spell of chisel re-handling. After all, once started who knows when it'll end...
So other than that it all went swimmingly. After that it tended more towards going drowningly.
On the plus side, let me point out the wisdom of having alternatives available in the form of a wide variety of tools from which to choose. Hmm? See? Not always as stoopid as I look...