Step 6 - Gettin' Groovy
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 Our task today starts with picking a frame and taking it apart. Tapping gently with a dead blow hammer accomplishes this quickly if we do it right. By tapping alternately at the top and the bottom we get the stile to slide off evenly so it doesn't bind up and crush a tenon or spread a mortise.
 A stacked dado is a set of special saw blades that are "stacked" to get an exact with of cut in a single pass. This set has a circular blade at the inside and outside face, with 2 wing fly cutters sandwiched between. Add more fly cutter for a wider groove. A precise width is achieved with steel shims that are placed between the cutters. Alignment marks are placed on the table saw top to indicate the front and back edges the blades cut as well as the high point of the cut.
 On the stiles, we don't want the groove to come out the end of the piece, so we have to make a "stopped groove". We mark where the ends of the groove will be and line these marks up with the end of cut marks on the table saw. Here I'm lining up to start a cut, after the saw is started I'll drop the board down into the blade and run it through until the end of groove line on the other end lines up with the cut line closest to me then lift it off of the blade. Because we have nice wide tenons, the curves at the ends of the cut are within the tenon area so the groove is full depth the entire distance where the panel will be.
 On the rails and stiles we can make a through groove by simply running the piece through the blade. Because stiles fit between two panels, they must be grooved on both edges. The depth of the grooves and the distance between the edge of the tenon and the edge of the board are the same (not by accident either) so cutting the grooves does not change the width of the tenon, nor does it leave gaps inside the framework where atmospheric moisture could collect.
 When the parts for each frame are completed and reassembled, the grooves line up perfectly. By reassembling the frame we can now accurately measure the size of the panel needed to fill this area. But we must temper these measurements with an awareness of the humidity level. If the humidity is high, these panels will shrink as the air dries out, so we'll want to fit them as tight as possible. If the humidity is low, the panels will expand when the weather gets damp, so we must leave a little room for this so the panels don't "pop" corner joints or buckle.
 Naturally, since each joint is hand fitted, it behooves us to mark them so that the same pieces go back together the same way and all the joints are back together as they were originally. So we label the parts of each sub-assembly as to which sub-assembly they are part of and orientation, but also the two pieces of each joint. Mortises are labeled on the face of the board with tape or pencil, the same label is written on the tenon that will go into that mortise. In this way, we could take all the sub-assemblies completely apart, toss all the parts in a pile and still be able to reassemble them in exactly the same way that they were to start with.
 Cutting the panels to size is somewhat easier on this piece than in many we've built because most of the filler panels are of a similar size; all of the panels are the same height except the doors, which are 1/8" shorter, all 4 of the side panels are the same, all 4 door panels are the same, two of the back panels are the same, the center back panel is wider.
Because most of these panels were made from book matched pieces resawn from a single piece of lumber, we want to keep the center of the panel in the center, so when we trim to width, we trim equal amounts off of both edges.
 I can ensure a good square panel if I use the crosscut sled to trim the panels to length. First I take just a blade width cut off one end of each panel to square that end, then go back and cut each panel to finished length. A check of the diagonal measurements confirms that each panel is perfectly square. This is important because the top and bottom edges of these panels will be in contact with the bottoms of the grooves they're seated in to add rigidity to the entire structure. we can do this without fear of expansion damage because wood does not expand or contract along it's length, only it's width and thickness. But a panel that isn't square will throw off the fit of all parts it connects to, throwing the sub-assembly out of square, and that may well prevent the finished assembly from being square.
The error may be only a little. So little that it would go unnoticed and unrepaired in a mass-produced piece; they engineer those to allow for the errors that will creep in by cutting joints a little sloppy and relying on hardware to hold it together. For a while anyway.
 After cutting each panel I take a hand sander with a coarse grade of paper and dress the edges of the panel. this removes any burrs, splinters, and rough edges that would prevent the panel from sliding into it's frame.
 Then we fit the panel into it's frame. A clamp is used to draw the frame tight at the bottom of the panel. If it won't slide in, I trim off just a hair more... literally. We're back to "fussy-fitting" where the old adage of 'It's easier to take off a little more wood than it is to put some back' applies. this final fitting is generally done with sand paper and a sanding block -- it's that precise.
 But, when it's all done, a finely fitted sub-assembly is a thing of beauty; tight joints, square corners, snug panels without any visible seams in the panels. This is the back of the cabinet -- stood on end for this photograph. After this we have the 4 sides and two doors to do before this step is complete. These simply repeat the process described above for each of these sub-assemblies.
We're still not using any glue. Once all the sub-assemblies are done, I will fit them together on a good flat surface and make sure that they all fit together and align properly with one another -- using masking tape to hold them together -- before even thinking about glue. Plus, there are some grooves and rabbets that need to be milled into some of these parts, and being able to take pieces back off to do this will avoid having to balance full panels in an upright position as I pass the part through the table saw.
Besides, the ends of the filler panels need to be sealed to prevent splitting before the final assembly can take place, but we'll get to that later.
Man Hours: 8½
Materials: none new.
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