Thursday, December 17

Looong Day

This is going to be a long one, so I’m in early. I mentioned on Tuesday that while cutting ribbon strips for Ann’s Tray Tables I also cut the maple and cherry strips for Dianne’s Cutting Board. That process went as most do, starting with jointing the blanks to establish one flat face and one flat edge that is square to the jointed face. Then surface planed them just until the other face was clean. In this case I’m not shooting for any particular thickness, in fact using some random width strips adds interest to the pattern. Because these surfaces will become my glue joints, I also used the wide drum sander to remove any ripples these machines left behind. I set these strips aside while I glued up the ribbon panels for Ann’s tables. This morning I start by removing the clamps from the ribbon panels and checking to see if they need to be scraped before machining – hardened glue globs will chip the expensive knives in our surface planer – but we’re in good shape, I did a good job of removing the squeeze-out with a damp rag after clamping. I trim the panels to finished with, being careful to take equal amounts off of each edge to keep the center of the panel centered. I put enough effort into getting a nice pattern that I don’t want to make it lopsided now. Then I run the panels through the surface planer. When we bough this large planer one of the considerations was the fact that it can handle a 15” wide tray panel. In the past we had to make these panels in two pieces, plane the halves smooth then joint the halves at the center joint and fair that out by hand. This is much simpler and worth the extra cost (about double) of going from a 13” planer to a 15”. I plane both sides, very gently; taking very light cuts to as not to cause chip-out since there are widely varying grain directions in the panel. The last 1/32 inch is taken off on the wide drum sander to produce a better surface. By the time they come out of the final pass they’re looking mighty good! Not only are they attractive, but all the joints are perfectly tight. Now I prepare the plywood backer panels. “Whoa, plywood? I thought you said plywood was bad!” Plywood is not my choice in most cases, but there are times when the special properties of plywood are desirable, even better then solid wood. This is one of those. The reason being that solid wood *will* contract and expand with humidity changes – that can not be stopped. In most cases I will design a piece to allow for movement so joinery doesn’t get popped open and panels don’t crack. In the case of these tables, the rails are quite delicate and don’t offer “meat” at the corner joints to be relied upon as the only means of holding the rails together, they need to be glued to a solid base as well. That can not be the ribbon panel because of the aforementioned expansion/contraction cycles, so I incorporate a plywood backer panel under the ribbon panel that will not expand and contract, so it can be used as that stable and stalwart base to which we can glue our frame rails. I use furniture quality veneered plywood for this, not Home Center stuff, so this is still very expensive and high quality material. After cutting a piece off of the large plywood panel (a little wider than I need) I flip it over and trim up the ”raw” edge, then flip it again and to a final trim on the first cut to be sure I have good straight, clean edges to work with. Then I use the big cut-off sled to cut them to rough length. I’ll cut to finished length later. The backer panels are cut so that they are 1/8” wider than the ribbon panels, allowing me to leave a 1/16” space on either side inside the side rails. This is to allow room for the panel to expand into and to insure that glue inside the rail groove does not adhere the panel to either the backer or the rail. I apply a stripe of glue down just the center of both backer and ribbon panel, flip the ribbon panel onto the backer, center it side-to-side and apply clamps. Once both are done I’ll find heavy stuff – full gallon cans of finishing supplies work well – to set in the middle and apply pressure so the glue sticks there too. While the glue sets up on those I pull out my cutting board strips and arrange them to obtain a pleasing pattern. It is very important while doing this to remember that the template Dianne supplied (as all these templates are) is the shape of the INSIDE of her sink opening. If I cut the board to this size, it will fall into the sink and be absolutely useless, to achieve the desired use it must have a lip around the edges that will sit on the rim of the sink. I make this lip ¾” wide, so while arranging wood strips I leave an inch all around – just to be sure. I also need to keep an eye on the orientation of the template. Because I’m working with the visible side of the board, the side marked as TOP must be up. I trace around the template, more to provide a means of getting the strips back just as they are now than for anything else. I reassemble the collection on top of a collection of clamps. To reduce material waste I do not try to make the board blank into a rectangle, so I end up with a challenging pyramid shape to clamp up. I remove the strips two at a time; one to glue and put back, one to allow room to work in. I start at the wide end and when I get to where I can tighten the first set of clamps I do, that way the glue does not dry out before I get the whole collection glued and assembled. When all are glued and clamped I wipe the set down with a damp rag to remove the squeeze-out. I’m not stingy with this glue-up; I’d rather waste a little glue than have a joint be glue-starved and fail. This board will subjected to repeated washing and during, so I use a polyurethane type III glue that is waterproof, but a joint that is not solidly boned together will allow water to creep in and star “working” that spot in the board, and that can break most any glue over time. I want this board to outlast Dianne’s kitchen sink, so we’ll build it right. While the glue in the cutting board is setting up I take Ann’s tray panels out to the table saw and use the cross-cut sled to trim them to finished length. By cutting backer and ribbon panels to length at the same time I insure that both end up square and even. I do the finish sanding now. Then I take them into the finishing room and shoot the ribbon panels with one coat of lacquer. Why? Two reasons. One: I need to finish at least the upper edges of the ribbon panels so when they contract they will not show slivers of unfinished wood along the sides. I also tape off the ends so I can apply lacquer to the ends of the ribbon panels – but not to the backer panels. This allows me to get a good glue joint between backer and side rail, but will prevent glue from sticking to the ribbon panel. While the lacquer is drying I plough the panel grooves into the rail blanks, round-over the inside top edge or each rail and sand the inside faces only. Sanding and routing the rest of the rails will be done later. Doing this on the inside face now means I don’t have to risk scratching up the lacquered panel by shaping and sanding the insides of the rails after assembly. I cut the rails to length, miter the ends, and fit them around the panels. I need these to be absolutely perfect: no gaps in the miter and the lengths correct. Too short and the corner won’t close, too long and the rail will not seat tightly on the backer panel, weakening the assembly. As in anything, “absolutely perfect” takes time, working slowly and being very careful. If I cut a little too much off I’ll be milling out a new set of rails. Once both trays are fitted, I glue them up by taking the rails back off – one at a time – and applying glue very carefully to the lower edge of the groove with a small artists paint brush then placing it back in place on the assembly and taking the next one off. When all rails have been glued to the backer and to each other I apply clamps to gently pull them together. This takes only firm pressure, no need to “go gorilla” on these. This assembly will be allowed to set up overnight to be sure the glue sets up well before I work with them any further. While I’m waiting on that… I trim the cutting board blank to width and joint the “hypotenuse” side of the board to make it smooth and straight. And run the board through the surface planer to smooth and flatten both sides. As with the ribbon panels, the final few passes are done on the drum sander to get a superior surface. I lay the board bottom side up on the work bench and place the template – make sure it is TOP side DOWN now! – on the blank and trace carefully around it with a sharp pencil so the line is right at the edge of the template. We can not cut on that line though – remember the lip? – so I use a good ruler to project out ¾” from this line and make a series of tick marks. When that is done I play connect-the-dots to create the final shape of the board. Now we can go to the band saw and cut out the shape. As always I cut just a hair outside the line so I have a little wood left to use the stationary belt sander in removing saw marks and fairing the shape as I sand back to the lines. But I don’t want to leave too much, this is 7/8” thick maple after all and will require some effort to remove the waste. Here is where the tricky part begins. We need to route a ¾” wide lip on the sides that will sit on the edge of the sink. How do we do that? Well, I do it by chucking a bowl making bit into the router table and setting the guide fence to limit the depth of cut. Unlike most rounded router bits, the bowl making bit has a fairly substantial flat area on top – which is made to smooth the bottom of a shallow bowl or tray – that works well to produce an even surface on the underside of the lip. I make the lip in shallow passes, stepping the fence back a little on each pass until the bottom of the board gets to the line I traced around the template. Then I make one more clean-up pass that makes the part of the board that pokes down into the sink just a smidge smaller than the sink opening. I’d rather have it fit just a little loose – the lip is plenty wide to support it – than to have it end up too tight. You don’t want to have to pound it into the sink opening! Sanding is next. Lots of sanding. Fortunately The large flat surfaces can be sanded through the various grits (120, 150, 180, & 220) needed to achieve the soft glow we seek once the wood is oiled. OK, you caught me… I do not sand the bottom of the board all the way to 220, I stop after 150, but the visible parts are sanded, and sanded and sanded some more. The final pass, even on the top, is done by hand to get the best finish possible. Once that is complete, I tack away the sanding dust, take a sinus pill to fight the headache I’m going to get from breathing all the really fine sanding dust, and go into the finishing room to apply the first coat of oil. This is food-safe mineral oil. Never use vegetable oil or nut oil to treat a cutting board as these will go rancid in time and could bleed unpleasant stuff back into the food you are preparing that may make you sick. Mineral oil does not spoil. Nor does it form a film like most finishes that would flake off into your food. Most finishes are non-toxic once they’re cured, but if you want to try new flavorings in your food, look to some new spices not polyurethane, lacquer or shellac. The oil is applied very wet and rubbed into the wood –literally- by hand. I can use a rag, but I prefer to use the palm of my hand because it allows me to feel a little extra drag where areas of the board are especially thirsty and are drinking in the oil faster than the rest. I continue rubbing the oil for at least 10 minutes, moving it around the surface making sure that areas that need it are getting it, them wipe the excess oil off with a clean rag. I’ll let the board set overnight and apply another coat is just the same way tomorrow. I’ll finish out the day by milling out the basic parts for the latch blocks for Ann’s tables. Actually making these parts is tricky. It’s almost 10:00 PM now and I’m tired. I’ll call it a day for today and get to this step when my brain is again up to the task. G’Nite! NOTE: Turns out I was too tired to write and post this episode Wednesday night. My apologies to those who eagerly await each episode of this oh-so- thrilling blog (grin). I posted this during lunch on Thursday so please forgive any salad dressing stains you find while reading.

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