Wednesday, February 24

Lumber Prep - phase 1

A couple of weeks ago I brought in a whole mess of rough sawn walnut from our lumber piles outside and stood it against a wall inside the shop. I let it stand there for a while to acclimate to the different conditions inside the shop. If a board is going to want to twist, warp or cup as it changes moisture levels I want to know it before I cut it into parts. I can still use such a board for smaller parts, but the longer pieces need to come from the flattest, straightest boards I can find. I move the surface planer around beside the workbench where I have enough room on the in-feed and out-feed sides to maneuver 8 to 10 foot long boards. I feed them in from where they are standing and take them off over by the band saw, where I can then slide them onto the workbench next to the planer, stacking them up as they come through. What I’m doing here is to remove the rough layer of wood making it easier to see the coloring and grain pattern of the wood. I’m removing as little wood as possible right now to achieve this clarity. When I’m done I have a pile of various sized planks stacked on the bench. Now I move the planer out of the way (it weighs almost 600 pounds so it’s a good think it has wheels!) and sort through the planks looking for the pieces I want for the first parts to be made. I stack the rejected candidates in this first round on the floor. I always start parts-making by selecting wood for the largest parts first, then working down toward the smallest. Often I can make the smallest parts from cut-offs produced in making the larger parts, but more importantly is that business about needing the flattest, straightest pieces for the largest parts. It would be heart-breaking to find that I’d cut up a nice flat piece into small parts then find that the rest are not as well suited for a large part. Once I have found the pieces I want, I match them up for color and grain pattern. The idea here is to minimize the variance where one piece of wood joins another. I’ll be making 2 panels 13-15 inches wide and almost 7 feet long. Each will require 3 pieces of wood to attain that width, and I want to hide those edge joints as much as possible. After the panel is glued up it will be planed to finished thickness and teh ugly spots will be removed. When I have achieved the best matches I can – for perfection is difficult on parts as long as these. That would require boards that show perfectly straight grain for their entire length and width. Something you don’t see much anymore because all the old growth timber has been cut and the smaller trees they’re cutting now rarely yield such perfect boards – I mark them with a big 'V' across the back face of all three boards to keep them properly oriented during the next step, which is to joint them. Jointing is done on a Jointer. (Duh!) It is called this because one of its primary functions is making very straight, square edges that can be glued together to join multiple small boards into wide ones. When we bought this machine we got one with a bed that is 8” wide and a little over 6 feet long because we sometimes need to joint long boards like these. A smaller model with a shorter bed would make it difficult to straighten a long board because a long, sweeping curve would just ride on the bed, making the board narrower with each pass, but no straighter. There are larger models too, some industrial models look like aircraft carriers, but this was the largest tool we had room for in this shop. And because when you move into the industrial grade, prices quadruple! As the boards are jointed they are laid back on the work bench so I can check to see that the joints between boards mate up well with no gaps. If I find gaps, I joint those two surfaces again. When I’m happy with them they go into the assembly room where I have two tables set up and a battery of clamps at hand, the edges get a coat of Type III polyurethane glue, I feel to make sure the jointed faces, which are down against the clamps, are mated up well to reduce ridges that will have to be removed later. I use poly glue for panelizing because this is not a joint that will need to be taken apart someday for maintenance, as most joinery will. Hopefully not for a hundred years or so, but eventually wood movement and stresses will cause the piece to need re-gluing. Where that is a possibility I use standard (aliphatic) wood glue so these joints will be repairable when the time comes. I used to use hide glue for all my joinery, but this requires mixing glue crystals with water and keeping it at 170° all the time it’s being used. And left-over glue in the pot tends to stink like something dead – because it’s made from animal hide. The extra hassles make it unsuitable for new furniture construction where traditionalism is not required and time is money. It’s still the best choice for antique restoration though. I’ll let this assembly sit in clamps overnight so the glue can develop a good hold. Poly glue takes 5 days to develop its maximum holding power as it cures but will provide a good “grip” in a few hours, especially if the joints do not have stress in them from forcing poorly fitted boards together under clamping pressure to close up gaps. The rest of the afternoon will be spent jointing the other set of boards for the second side panel so I can glue it up first thing in the morning. Then I’ll move onto making rail and stile stock. Why didn’t I make the sides in frame and panel construction? Oh, well, that’s because of that hexagonal “belly” the clock has. The pieces that will slope out from the sides will be too small to make as frame and panel, so I’d have had to switch from frame and panel to solid wood then back to frame and panel. That, I think, would look weird so I elected to make the sides of solid wood. The back, the front doors, and the base front will be frame & panel using a fancy fluted stock with a rope trim insert. That ought to be fun!

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