I put together today the Wogden settrigger castings I bougth from Blackley.
It was easier than I thought. It took about 6 hours. Small parts were soft soldered to a piece of 1/8” sheet steel before drilling holes. I measured the size of the “dimples” and picked the corresponding screw and pin sizes
Main spring screw: 4mm
Weak spring screw: 3mm
Trigger screw: 3mm
Rear hook pin: 2mm
I’m a bit surprised it went well. There is very little steel left around some of the holes.
The bolsters on the trigger plate are only 1,6mm (1/16”) thick.
The main spring was supplied as a spring steel casting. The weak spring I cut out of 1/16” thick spring steel. Both springs were heated to 1500 F (825C) and quenched in oil. They were tempered for 1 hour at 750
oF (400
oC). I used a heat treating oven. The springs are a lot smaller than the ones I’m using on the single phase double set trigger I built.
http://americanlongrifles.org/forum/index.php?topic=20180.msg190836#msg190836 The trigger seems to function correctly, so I think I probably could have designed the springs a lot smaller.
One of the big differences with the wogden trigger contra the SPDT trigger is that the triggerblad does not drop down after engaging the sear. Tension from the weak spring on the rear hooked hinders this. As a consequence, the trigger must be set first before the lock can be set. This seems a bit dangerous. Are all single set trigger like this?
Best regards
Rolf