(Ya know, writing this in parts is kind of difficult…. I have to keep going back to my old posts to read where I left off.)
I may have said that the cabinet is frame & panel construction on all four sides, with each side the same.
Elm frames taped together
So, this is kind of what it will look like — hopefully, I can find better material for the panels than cardboard.
Let’s see. First things first: I milled all the frame parts to thickness & width, then cut to length (straightening grain where possible as shown last time).
Construction is mortise & tenon. This time around, I used a Festool Domino* machine to cut the mortises. Clamping the frame pieces required a little different set up because they are rather narrow plus thinner than a typical 3/4″.
Mortising the Stiles
The frames are only 9/16″ thick so I had to use some Formica laminate to shim them into a position where the cutter would be centered on the edge. The clamping set-up helps keep the stile against the machine, but mostly, it presses the stile down to the table so the mortise is cut in the middle. I have a scrap piece of frame against the Domino so the wood clamp mechanism doesn’t rack. Looking closely you can see the plywood spacer used to position the end of the stile in relation to the cutter. (There’s an indexing pin on either side of the cutter that can’t be seen here.)
Mortising stiles for center rail
Mortising for the center rail required some changes. First off, I used a thicker cutter — 6mm vs 5mm — and I added the extensions shown so I could index the cut further away from the end. I prefer some kind of fixed stop like this or a block of wood rather than a pencil line because it removes any guess work or chance of error about where the cut should go. Well, usually it does:
The Domino machine can cut three widths of mortise. After cutting for the bottom rail which is wider, I reset the width on the machine, but forgot to change the spacer block. Oops!
Next step is to cut the tenons.
Cutting the shoulders on the rails
All the rails have been cut to a length that includes an extra 1-1/4″ to allow for 5/8″ long tenons on each side. (I use a Forrest 80 tooth blade for almost all my crosscutting because it gives a very clean edge.) My blade height is set just slightly higher than half the thickness of the needed tenon. This way, I don’t have to do a lot of clean-up where the shoulder meets the tenon. (So, for example, if my tenon needs to be 5mm thick, I’ll try to set the blade to leave 4.8mm of thickness at the bottom of the tenon at the shoulder.)
After cutting shoulders, I cut the cheeks:
Cutting the tenon cheeks on the table saw
I have a Vega rip fence on my Rockwell table saw. The Vega has a nice micro adjust feature that allows me to fine-tune it’s distance from the blade so I get the tenon thickness exact. (Here I’m using the stock Combo blade that came with my Powermatic saw. It gives a smoother than expected rip cut.) The fence also has a channel in the top for sliding various accessories along it. I built this simple Tenoning jig years ago out of scrap. It has served me very well.
After cutting the cheeks, I trim off the long edges of the tenons on the bandsaw. (No pic) Then I round the long edges with a Swedish single cut mill file.
Rounding the tenons
I fit each tenon to a specific mortise. assemble the frames, and check for square.
Next I’ll mortise the leg blanks and cut tenons on the front & back leg rails (stretchers).
Mortising the legs for upper stretcher
Mortising for bottom stretcher
Mortises in legs; jig still in place
The stand’s legs are still square & haven’t been sawn to shape. I made up a jig that references off the top & inside face of a pair of legs (back legs in this case). I’ve rotated the legs so the two surfaces that face each other (left to right vs front to back) are up & ready to receive the mortise. I’ve marked on the jig the center lines of each mortise. (If you were able to look closely at the lines, you would see that they are not equidistant from the inside edge of the leg. This is because the bit does not cut an equal distance from the scribed line on the machine. The lines are about 0.7mm off center and there appears to be no fix for it [see * below].) For the second set of mortises, I add a spacer. I have two dowels in the edges to maintain alignment and I’ve extended the reference lines. The last picture shows the mortises complete.
The work on the Stretchers’ tenons is similar to the frame tenons so I don’t have any pics.
The Retirement Cab has to sit idle for a while now so I can catch up on a couple of paying projects.
* I bought the Festool Domino machine the day it went on sale. I really like it for what it does. But it has two flaws that don’t seem to have any fix.
1) The cutting bit (looks kind of like a brad point drill bit) seems to “climb” in the mortise. This means that the mortise is not perfectly parallel to the referencing fence (be that the table as in the earlier pictures or the jig in the last pictures) In this project, it’s not so bad & I can sand out any problems. But if I were cutting facing mortises & using a loose tenon,to join them, the error would double.
2) The second flaw is mentioned above: the center reference lines (of which there are three on three different surfaces) do not indicate the exact center of the cut. So in some cases, I have to adjust my cut to get it centered. Now if I’m using the indexing pins mentioned at the very beginning, one of the pins is excentric and can be rotated on it’s axis to correct for this error. But the “wings” I used for the center mortises don’t adjust so I again have to make corrections via trial & error. For such an expensive machine, it’s a pain.
When I created the link to the Festool site, I found that they have come out with a new model that’s slightly different to mine. Maybe they’ve corrected these problems (but probably not).
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