I am sure someone here would probably make some cuts and measure it for you.
I could do that in a day or to if you need me to. In the mean time, my
Porter Cable biscuit cutter is still set up in the factory default setting.
I think it cuts 1/16 - 1/8" extra depth (For a size 20). This is handy as it
allows for almost 1/2" of missalignment of the two slots (length-wise, not
thickness-wise) and still allows the joint to come together. You wouldn't
want to get too carried away on this extra depth becasue at some point the
biscuit won't be centered properly (located more in one baord than the
other) and you will loose joint strength. I think the 1/16" - 1/8" is about
right though, in my opinion.

Joe In Denver
My Woodworking Website:
www.the-wildings.com/shop/

"NewCabMaker" wrote in message
...
I recently bought my first biscuit joiner, a used Porter-Cable. The
previous owner had apparently set the depth too shallow because when
dry-fitting boards the biscuits bottom out before the joint closes.

I increased the depth with the fine adjustment for my first test joint
so the joint closes when dry fitting. But when I added glue to the slots
I started to wonder if I ought to cut a little deeper yet to give more
space for the glue.

How can I set the depth to the ideal, or am I worrying about something
that's not critical?

Bill