Work continues on my Armoire and I’ve also received a deposit for one commission and a verbal approval of another — I won’t count on it until the check is in my hand which is scheduled for the 31st. I’ve ordered the legs for the for sure commission and am waiting for my supplier to get more of the reclaimed fence boards that will be used for it, the holidays are great but it does change business hours for some of the suppliers I deal with but that’s okay, it allows me more time to work on my personal Armoire project.
Speaking of which, the realization of how complicated and intense this project is strikes me most days. Keeping track of all the parts and their relationship to one another is vital and I can see how easy it would be to make one error and throw a huge monkey wrench into the works! If you check the drawing at the right it’ll help illustrate what phase of work is currently being done. The lower drawer stretchers are complete; dovetailed into the legs. Next up are the three drawer stretchers which are joined to the left leg and center section with a drawbored, mortise and tenon joint. By adding that peg to an already strong joint the strength of it is increased dramatically. Assembly of this Armoire will be quite a challenge and by draw boring this part of the frames I won’t have to worry about clamping all of it — it’ll be tricky and I’m keeping my fingers crossed that the sequence in my mind will match reality!
First up is cutting the mortises and making sure to cut them on the insides of the leg and center section. For this part of the drawbored mortise and tenon joinery I’ll use a hollow chisel mortiser. After all of those were cut out, they needed to be drilled with a 3/16″ bit for the peg. To locate the center of the mortise a 1/4″ set up block was pressed against one wall so a pencil line could extend across the face. To insure this hole is square, I set up a fence on the drill press, the hole goes completely through the legs.
The top of the mortise is the top of the stretcher so only one side needs to have a shoulder cut. There are a couple of ways to go about this and the method used here was to use a dado head on the tablesaw to remove the bulk of the material. I needed 26 1/2″ for the length of the drawer so used a piece of MDF as a setup guide to insure that I got it. The stop block on the miter gauge has been adjusted for the length of the tenon. Once all of the pieces were roughed out with the saw it’s time to fine tune them individually to their corresponding mortise. With twelve joints to fit my goal is to set up my work for efficiency, here’s the bench set up for this phase:
The leg is clamped to the right side of the bench so I can lay out the width of the tenon. At left I’ve clamped my portable workbench which brings the work to a good height for me. Here’s where the shoulders and cheeks are cut and sized to fit the mortises. Let me illustrate my method for this part of the drawbored mortise and tenon joint with this slide show:
I’m sure you can see where keeping track of which piece goes where is so critical, the first step in the assembly sequence will be gluing and draw boring these mortise and tenoned pieces together. Marking all of the pieces as I explained in this previous blog really helps me stay on track with that.
After all of the mortise and tenon joints fit it was time for locating the pegs for the draw boring portion of the joint. The theory behind drawboring is that a peg is driven through the leg into an offset hole drilled into the tenon. Since that hole is offset towards the shoulder it will pull tighter as the peg is pounded home. Problem number one is locating the center of the hole. You know I like to use golf balls for handles on files and rasps, they just give you a nice grip so here’s my center finder for this step made from a piece of 3/16″ rod. I remembered reading somewhere that to put a centered point on a rod you need to rotate the rod while placing it against a rotating abrasive surface. I made this because a scratch awl is too thin to stay centered in the 3/16″ hole.
To be on the safe side I did a few practice joints. Getting the offset of the hole is critical, if you locate the hole too far towards the shoulder you’ll have a devil of a time getting the peg through the hole and it may even break! The sequence is best shown with this slide show:
Now that the practice drawbored mortise and tenon joint is completed successfully it’s time to do the real thing. This was accomplished by clamping the pieces together, marking the centers and then drilling the holes with the drill press. As you can see, I’ll be needing to make a bunch of 3/16″ Walnut pegs but there’s a way to go before I’m ready for that step. Next up are the mortise and tenons required for the stretchers between the front and back frames. Same basic process will be followed doing what is sometimes referred to as “hybrid woodworking” where the power tools perform the grunt work and hand tools finish the process. The grooves for the panels will also be routed — that should be all that’s left to do before the final smooth plane work on all of the pieces.