I purchased and Akeda jig a few months ago (lots of raves on the new
group). I have begun using it to build a bunch of drawers for
kitchen cabinets. My first set of 10 drawers came out perfect. They
were made from solid birch. I was not so lucky on the second set of
drawers. The sides are 1/2" baltic birch and the front and back are
3/4" baltic birch. A front board will finish the drawers.

I made some tests to establish the height of the bit and got it "just
right" after a couple of tries. I then proceeded to do the half blind
joints for the first 5 drawers. I cut the tails in the sides for all
five drawers. Then I switched to the pins on the five sets of front
and back pieces for the drawers. I was very disappointed to find that
the joints did not fit correctly. The tails do not mate tightly to
the pins - there is a 1/16 inch gap; i.e., the is a gap holding the
two pieces apart by 1/16 inch.

I checked the pieces with my test pieces. The tails in the drawer
sides fit perfectly with the pins in my test pieces. Something went
wrong when I cut the pins on the front and back pieces. My first
thought was that the router bit dropped or the router depth changed.
But, it would have happened just as I changed from tails to pins -
too much of a coincidence! The guides are all at the same height and
are in there tight.

Anybody got suggestions on what I did wrong?

Len