Leuf (in firstname.lastname@example.org) said:
|| Leuf (in email@example.com) said:
||| On Thu, 8 Jun 2006 19:36:10 -0500, "Morris Dovey"
|||| A stop dado would bear a strong resemblance to a mortise, yes? I
|||| like this idea; but think it'd be easier to machine the angled
|||| tenon on the ends of the dividers with straight mortises.
||| The dividers are pretty thin, I wouldn't go any thicker than 1/4".
||| Wouldn't leave you much of anything for an angled tenon would it?
|| Hmm. Let's see - using 1/4" stock for the divider, if the angle
|| was 45 degrees I would have about .25" * sqrt(2) = 11/32+" to
|| work with if the tenon didn't need to be square-ended. So if I
|| allowed 1/32" (twice) for the shoulders, then the tenon could be
|| 9/32" thick and I think it'd work ok.
|| What makes this fun is that the tenon I just calculated is actually
|| thicker than the stock from which it was made (a drawing will
|| Aren't geometry and trig wonderful? :-)
| Okay I did a drawing and I think the sticking point is your "didn't
| need to be square-ended." If it isn't square ended what's the
| point? You'd have no contact on that side. I can see you can cheat
| a little and have maybe 1/3 to 1/2 of the tenon be angled, but you
| aren't getting 9/32".
If I cut as I described, I'd only have 1/32" bearing on the side with
the 45 deg angle, roughly 1/2 of what a square-ended tenon would
provide at the top and bottom, and 9/32" on the side with the 135 deg
angle. The long shoulders only provide 1/32" to resist compression
(that's probably enough, tho) but the top and bottom (above and below
the tenon) could be in the 1/4 - 1/2" range which would surely be
The short side of the tenon doesn't need to do much. If the divider is
pushed against the short side, the shoulders (especially above and
below) will act to prevent movement; and if the divider is pushed
against the long side of the tenon, well - that's where the tenon is
strongest. I think it'll work. What /I/ don't like is the empty
airspace in the mortise.
| By my not very accurate line drawing if I insisted on fully square
| ended for a 1/8" deep mortise I had a width around .2" or 13/64".
| And the grain is running diagonally so it's not nearly as strong as
| a normal tenon of the same size. At 1/4" deep I was down to about
| Would it really be easier to do it this way with your setup? I am
| trying to picture how you'd do the angled tenons. Hold the
| workpiece on edge? Or on its face and flip it to do the other side?
Easiest way would be to set up a fixture to hold the board on edge at
the angle at which it'll fit in the tray, tilt the router to
horizontal, and write a program to run the router around the tenon (a
"race-track" toolpath). If I allow 1/4" shoulder at top and bottom and
use a 1/4" square-ended bit, it can all be done in a single pass in
the y-z plane.
For the mortises, I'd clamp the side/end pieces flat and parallel to
the x-axis and cut the matching mortises with the spindle vertically
oriented. The corner joints will be fairly straight-forward with the
spindle in horizontal orientation.
| Leave it to us to overcomplicate something someone did with a hand |
I'm not sure about "overcomplicate". Adrian just wanted one of these
things for his own home, and he was willing to put a lot of hours into
a single tray to get it just right using neandertools. I'm looking to
produce a version that is equally attractive and functional but in
larger quantities and with minimal man- and machine-minutes per unit.
I share your misgivings about the diagonal grain in the tenon; and
plan to abuse the first unit with a rubber mallet as soon as the glue
has cured to see if it's really a problem. If it'll survive a
reasonable pummeling, then I give it the concrete floor test from 6'
up; and if it survives /that/, I'll hang it on the wall and make more.
I suspect that application of glue and fitting all those joints
together at the same time is going to be /really/ interesting. :-)
DeSoto, Iowa USA