"Larry W" wrote in message
...
In article ,
-MIKE- wrote:
On 10/4/10 8:32 PM, J. Clarke wrote:
...snipped...
What is unnecessary?


Allowing "room for glue" in a M&T joint.

Not really what you guys are talking about, but in a blind M&T, it is
important to leave room for glue - at the bottom ot the mortise, by making
it very slightly deeper than the tenon is long. Otherwise any glue that
collects there as the tenon is assembled may keep the tenoned piece
from fully seating.


That is correct, the glue that gets trapped inside the mortice will keep the
tennon from going in all the way if the mortise is not deep enough to
accomidate the glue also.

However, Originally I was responding to the "Doesen't seem to leave room for
the glue" comment concerning the new BridgeCity Tennon maker. I does not
have any thing to do witht he length of the tennon or the depth of the
mortise. It works to size the tennon sides to fit the mortise sides. A
close fit that would scrape off excess glue, "not leaving room for the glue"
is how I read that comment. That would be a false assumption.