Monday, February 26

Monday – Tray Tops

Before getting back to Carol’s tables I needed to wrap up some things – literally. We received two orders for on-hand items over the weekend, so I needed to package these up and get them ready to go out. We also got an order for some bag handles that needed to be finished with polyurethane, so I applied the finish and got out of Dodge for an hour to allow it to set up before I started making saw dust.
But before I left, I figured I could go ahead and attach the mount blocks to the legs. These parts were already made, just needed to be assembled with washers and screws.

Our new building is almost ready, and I’m REALLY looking forward to having a separate, dedicated finishing room that can be closed off to keep dust out so we can continue working even while finish dries on another project.

Once it was safe, I took the panel of 1/8” Baltic Birch ply that Marie and I dug out over the weekend and sliced it up into backer panels. A full sheet is 5’ x 5’ and being only 1/8” thick it’s difficult to handle until it gets cut down into smaller pieces, so I cut the parts oversized because I knew they would need some “cleaning up”. Here I’m using a cut-off sled to trim them to precise length while keeping them perfectly square. Ok, yes, they are *rectangular*, what I mean is that the corners are all exactly 90°.

After the first one is trimmed to size, I check to be sure everything will fit right by placing the rails around the backer panel and checking to see that the rails fit snugly against the panel, and yet all the corners meet up properly. If the panel is a hair too big, the corners will have gaps, too small and the panel will ‘rattle’ in the frame. Either condition will result in weak joinery and possible failure in time.

Then I trim to size the ribbon panels that have been sitting around in the shop for nearly two weeks. I built these first to give them as much time as possible, preferably through a couple of cycles of high/low humidity, to see if they were going to have any tendency to crack. They didn’t. Again size is critical. The length needs to be the same as the backer panels, but the width needs to be 1/8” narrower than the backer so I can leave a small expansion gap on each side where the wood can go when it expands. If we are in the midst of a high humidity period, I’ll make this gap smaller because the wood has already expanded. But it’s been dry most of yesterday and all last night and today. I glue the ribbon panel to the backer ONLY down the center so the solid wood tray surface can move freely as it shrinks and expands.

Then it’s time to install the rails. I dry fit each set first. You may recall that when we cut the rails we did so using a special sequence that allows the grain of the wood to flow smoothly around all four of the corners, not just three. The parts were marked for alignment so close attention needs to be paid to getting them installed in the proper places. Glue is applied only to the *bottom* of the groove which houses the tray panel and backer. We do not want to glue the ribbon panel part to the rails – it must be free to move – but the backer panel needs to be solidly glued to the rails.

Band clamps are then installed to pull all the corners together firmly while the glue dries.

At the end of the day all four tray tops are assembled and clamped. These will set overnight to let the glue cure. Tomorrow we’ll “pretty them up” and attach the legs.

See you then!

Doug-Bob

No comments:

Post a Comment

Appropriate comments are welcome. All comments are reviewed before being posted. Spam messages (anything not a direct discussion of this message) and all profanity will be deleted. Don't waste your time or mine by posting trash here.