I am continuing to make progress on the frame and panel lid that I am building for the bottom of my workbench base.
You can read /see what was done previously here:
- Part 1 – Design, milling, and chopping of the mortises in the stiles.
- Part 2 – Finishing and fitting the tenons on the rails.
- Part 3 – Making the panels and the wedges for the tenons.
In this post, I’ll cut the saw kerfs in the through tenons, glue-up the lid, and trim and fit the lid to the base.
The first thing that I had to do was mark the location of the kerfs. I set a pair of dividers to a width that looked appropriate. I just eyeballed it and didn’t measure anything. I pricked a mark on each side of the ends of the tenons.
I then roughly penciled some lines to show me where to saw.
I cut two kerfs in each of the six tenons.
The beauty of the wedged mortise and tenon joint is that it has its own mechanical forces that hold it together and doesn’t rely solely on glue. If fact, glue is really optional with this joint. It doesn’t hurt to add it though and I will. By widening the mortise on the outside edge of the joint, the wedges will fan out the end of the tenon and create a joint that can’t be pulled apart.
The final step that was needed before I could begin the assembly was to widen the outside edges of the mortise. When I originally chopped the mortises, I tried to keep the walls square to the edge. Now I want to chisel away just a bit more to make some room for the tenon to fan out.
I created a taper approximately 1/16″ wider than the rest of the mortise that tapered away to nothing at about 1″ depth.
Well… I think I’m ready for the glue-up… I hate glue-ups! I know all of these joints fit, I’ve tested them all. This really should be no problem, but there’s always that fear of the glue starting to dry before everything is in place; or of ruining a part that took so long to make.
OK, here goes:
I brushed glue into the three mortises on one stile and the three corresponding tenons. I put these three joints together, and then started apply the glue to both surfaces of the other three joints. I was trying to move quickly so and I didn’t stop to take any pictures. I’m sure you can imaging brushing glue.
With the other three joints glued, I added the second stile….
Ummmmm……. Ooooh….. Shit….. I think I forgot something. What an idiot! I had to take a picture of this.
I used a mallet to persuade the second stile to come back off the rails. I at least had the foresight to use a scrap bit of wood to protect the frame from the mallet.
I installed the two panels and then put the second stile back on. Whew… Saved it!
I used the mallet and the scrap block of wood to tap the stile all the way onto the rail tenons. There is no glue on the panels as they are designed to freely float in the frame grooves.
After that initial hiccup, I think I’m back on track. Now I need to install the wedges.
If I just started hammering in the wedges, the force on the end of the tenon could open up the shoulder of the joints. I used a clamp (and some more scrap wood to protect the frame) to pull the two stiles tightly against the rail.
I did run into a slight snag here. The thin end of my wedges were still to thick to go into the small kerf in the tenon. I should have checked this before proceeding with the glue-up. I quickly took all the wedges over to my disk sander, and in about 4 seconds each, put a fine point right at the tip of each wedge.
I applied a light coat of glue to the wedges and started to tap them in.
The trick here is that you want to drive each pair of wedges in evenly, otherwise you end up with a finished joint that looks like you used one thick wedge and one thin. I found that you need to go quite quickly because once you stop tapping on the wedge and leave it for about three seconds, the glue grips it and it is much harder to get the wedge moving again. I had a few wedges that broke when I went back to them and tried to drive them in a little further.
Once the wedges were in at both ends of the same rail, I removed the clamp and moved on to the next rail. I repeated the process for all three rails. As soon as the wedges are in, the clamp can come off without fear of the shoulders opening up. The mechanical strength of the joint keeps it tight.
With all the wedges in, I left the lid to dry.
I didn’t bother with any glue cleanup as the edges all need to be planed still.
The next morning everything had dried and was looking good. I used a cross-cut saw to trim off the excess tenon and wedges on all six joints.
Then I trimmed off the horns at the ends of the stiles. This was easy to do as during the original lay out, I had left myself knife lines to follow when I got to this point.
This is a small Tyzack & Turner saw that I bought in England last year and restored. I filed it 15 PPI cross-cut. I love it and it cuts beautifully. It made short work of this job.
With the horns and the tenons sawed off, I finished flushing them up with a block plane.
I still had some layout marks on the frame and to finish cleaning up the edges, I switched to a smoothing plane. I clamped the lid to the side of the workbench top with bar clamps. I can’t wait until I have vises and things like this will become much simpler.
On the ends of the lid, I didn’t take full length strokes to avoid splitting out the wood at the end of the cut. Instead, I planed from the edges towards the center.
I cleaned up all four edges of the lid and did a quick test fit. It fit, but only just. It was too tight and if left like that would bind when opening or closing. I switched to my Stanley 5 ½ to shave down all four edges of the lid a little. Though just as sharp as my smoothers, I have my 5 ½ set for taking a little heavier cut. The extra mass of the plane also helps to keep the plane moving on these longer cuts.
I took the last pass on the end grain with a freshly sharpened block plane and the ends came out glassy and reflective.
With the edges done, I wanted to clean up the face of the frames. The panels were already smoothed prior to assembly. I clamped the lid to the benchtop and smoothed the frame to remove and glue, layout marks, planer marks, and dirt from handling.
Here it is, finished and in place. It fits perfectly. Sorry for the crappy photo, I don’t know what happened here.
So, what did I learn during all this? Well, for starters, a frame and panel door/lid should have the panels installed before closing all the joints. OK. I knew that before. The real lessons learned were to check your wedge thickness against your saw kerfs before applying the glue. But far more importantly DON’T USE SAPELE FOR WEDGES. I dodged the bullet with this glue-up and it came out looking OK. I would have liked to drive the wedges in a little further but they were breaking on me. The crazy interlocking grain in sapele means that you are going to have grain runout and breaks are more likely. In the future I will stick to oak or some other straight grained strong hardwood.
In the next post, I will fit two pieces to fill the gaps between the stretchers and the ends of the panels. I’ll also install the hardware.
More soon(-ish, it might be a little while)
– Jonathan White