For instance, in building my first few blocks (including more than a few that ended up on the scrap pile), I discovered how difficult it is to keep a flat surface flat while sanding or planing it. No matter how careful I was, I invariably ended up with a rounded surface (high in the middle with low spots on the edges) or a slanting surface (higher on one end than the other), or some even more complexly distorted surface. Anything but flat!
This makes it all but impossible to make good glue joints, which demand two flat surfaces, face to face.
I had been using thickened epoxy to fill the rolling gaps between the spacers and cheeks, but that kind of slap-dash approach didn't seem right to me this time... Surely it wasn't impossible to get two small bits of wood to match up perfectly. I was determined to discover this woodworking secret.
However, the first challenge was to extract two rough cheeks, and two rough spacers -- with the right grain dictions -- from the slab of white oak on my work bench. This wasn't too difficult. The slab was 10/8" thick, so I thought I could cut three 3/8" thick cheeks from one piece, allowing some loss from sawing.
I didn't take photos of this process, but here is the result: a roughly-square block, after the one 3/8" slice has been already been take off on the bandsaw. It only remains to re-saw this into two pieces that will become the cheeks.
|A roughly square block|
|Re-sawn into two cheeks|
From the photo below, it looks like these roughly cut pieces are already flat. They are in fact close, but being freshly sawn, they need to be sanded smooth before assembly. This is where my previous efforts had turned nearly-flat bits of wood into smoothly-humped bits of wood. Very frustrating.
|Spacer cut for a long-grain to long-grain glue joint|
|My flat-sanding jig|
|The key to flat sanding: move piece, not sand paper!|
The purpose of the oak strip was to make it easy to sand small pieces, like the spacers, while keeping the faces 90 degrees to each other. This was another problem I'd had... when sanding with a sanding block, it is all to easy to end up with slanting faces.
By holding the piece against the rail and rubbing the piece up and down the rail, I was able to sand the piece while keeping the edges square to each other.
|Keeping small pieces square|
By holding the two spacers pressed together, it was easy to sand them both at the same time, thus guaranteeing two spacers of the same height.
|Two spacers exactly the same size! Wow!|
Here's how the bits look when laid together for fit. I discovered I could actually make the block a bit smaller than I had planned, so the cheeks are a little long.
I cut the recess in the bottom spacer and the rope-groove in the top spacer using my micro-plane rasps, as shown in a previous blog post.
|How the pieces fit together|
|The moment of truth...|
At least, that was the theory. Only time would tell. But as I was gazing admiringly at this tiny bit of woodwork, I realized I'd made one potentially serious mistake...
>>> Next Episode: Tail Block Takes Shape