Well this frame and panel lid seems to be taking me some considerable time to make. This will be part three, and I think that the whole process will end up taking me five posts. That’s my fault for sure, as I have been a little long winded and there will be well over a hundred images in the five posts. 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.
In this post, I’ll make the panels to fit within the frame and the wedges for the through tenons. In my last post, I ended with the dry fitting of the frame, but failed to show the joints going together. Here’s a couple of pictures to show it now.
To make the panels that will float within the lid frame, I picked through my remaining douglas fir. This is the wood that I had milled about two years ago for the sole purpose of building this bench. There’s not much of it left now.
I found some pieces that were somewhere between rift and quarter-sawn, and that had a distinctive separation between the pink heartwood and the white sapwood. These pieces were only 3-4 inches wide, but were thick enough that I could re-saw them and arrange them in a book-match pattern. It will be more work to piece the panels together in this fashion, but I think it will look good in the end.
I have shown in previous posts the steps I take to joint, plane, re-saw, and thickness lumber. I won’t bore you by repeating them again. After this process was done, I was left with many boards to work with for an aesthetically pleasing arrangement. As I re-sawed and planed them, I took particular care to keep the book-matched pairs together.
When planing these boards, I deliberately left them thicker than the intended final dimension of 5/8″. In the image below, they are probably closer to 3/4″. I will glue them up in sections narrow enough to feed through my 15″ planer.
Here’s the arrangement that I decided upon. I really like the alternating sapwood heartwood pattern and that the grain appears to continue from one panel into the next as though it had been from the same board.
I used the stickers that I had from my lumber pile as cauls. I first jointed the edges to ensure that they were flat, and then covered one edge of each with some glossy packing tape to prevent the glue from sticking. I set everything up in preparation for the glue-up.
By gluing up the panels each in two pieces, I will be able to clean them up after drying by feeding them back through the planer. This will also correct any slight misalignment from one edge to the next that might occur during glue-up. I have left the boards thicker than needed to allow for this.
Thank goodness that my order of Garret Wade clamps finally came in. I ordered them in March but didn’t get them until late September. I ordered 20 of them for small projects just like this that use a lot of clamps, but 24″ or 36″ clamps would just get in the way.
A few hours later, I removed the clamps and left the panels to dry overnight. I was sorely tempted to plane them the same day, but figured it would be safer to wait.
I scraped off the worst of the dried glue and then fed all four panels through my planer. I then flipped them over, adjusted the thickness to just a hair over 5/8″, and fed them through one last time. Any further planing from here will be done with the smoothing plane. To clean the surface left by the planer, I took a few passes on the panels with a No. 4 smoother. I will wait to do the final cleanup until after the panels are fully glued together.
I went back to the clamps and cauls to glue the panel sections together. I was very careful at this point to check for precise edge alignment as there is not much room for correction left. The panels are almost at the desired final thickness.
With the clamps removed and a freshly sharpened plane iron, I smoothed both faces of both panels. I had to resharpen my iron halfway through the second panel.
I made a load of shavings that my five year old son loves to feed one-by-one into the shop vac. Who ever said hand planing was quiet? Not in my shop. The next step was to unclog the shop vac… You saw that coming didn’t you?
I trued up one edge of the panel on my cross-cut sled at the table saw. I then measured the distance from one rail on the frame to the next and added 1″ to account for the two 1/2″ grooves. The wood will not expand or contract significantly along its length, so I can fit this dimension fairly tightly. I subtracted 1/16″ to make it a little easier to install during final assembly and glue-up. I then cut the panels to this length.
Next, I need to cut the panels to size in the cross grain dimension. The grooves in the stiles (¾”) are deeper than those in the rails (½”) to allow for wood movement. As I have said previously, I don’t expect to see much wood movement. This bench is staying in my shop and I don’t ever plan on moving. The relative humidity here is quite high throughout the year. That said, I thought I would check were the wood moisture level is now and look at some online wood movement calculators.
I took a moisture reading in some of the scrap wood milled from the same piece of lumber and it read 14%. That’s about what I was expecting. This wood has been in my garage shop for two years now.
I used this wood movement calculator that I found online. I specified coastal douglas fir, 21″ panel, radial-sawn wood, and a 14% starting moisture content. Here’s what I found:
- If the moisture content were to increase to 19% the panel would expand by 3/16″
- If the moisture content were to decrease to 6% the panel would shrink by 9/32″
I think either of these are extremely unlikely. My guess is that the wood in my workbench will never vary outside of the 12-16% range. This means that the panel should not change by more than 1/16″ in either direction.
Since I have plenty of room in the grooves I cut, I sized the panel to allow for 3/8″ of expansion. Way more that could ever be needed.
Before the panels are installed in the frame, I though it might be a good idea to add stopped chamfers around the inside edge of the frame. I added these to the legs and stretchers and thought they came out great. I got out my trim router and set the bit as deep as I dared. Any deeper and the bit would go into the groove and ruin the frame. As it was, only half the bearing was contacting the edge of the frame.
With this setting locked in, I made a test cut in a piece of scrap wood. The chamfer that it cut wasn’t even 1/16″ deep. It was so small that it could barely be seen. I decided that it wasn’t worth it and scrapped the idea. Sure, I could have milled some wood to fill the groove and let the router bearing ride on that, but I didn’t want these chamfers bad enough to go to that effort.
Before I can proceed to the glue-up, I need to make the wedges that will get driven in to the through tenons. When I milled up the sapele that I used on the workbench top, I saved an off-cut that I thought would work well for this purpose. I used a smoothing plane to taper the ends and form wedges.
Once a taper was formed, I cut it off with the cross-cut saw and planed down another.
The mortise gauge that I used earlier for laying out the mortise and tenon joinery, was still set to 3/8″. I slid the fence up tight against the first pin and marked the wedges.
There is no cut-out on the face of this mortise gauge to allow for the first pin to recess beneath the surface. This meant that I was marking slightly wider than my intended 3/8″, but that was OK and I can fine tune the width of the wedges with a block plane.
I sawed along the line and cut off the first small wedge. I cleaned up the edges with a block plane and used the mortise gauge to mark another line.
Each of the four larger wedges gave me three small ones. I checked the width of the wedges against the tenons that they will be driven into and planed them to final width.
In the next post, I’ll cut the saw kerfs in the ends of the through tenons and glue the whole thing up.
– Jonathan White