Today is the continuation of building a box for a carving knife set. In part one, I left off after cutting the sides. I will show the steps of glueing up the sides and bottom, cutting the lid, and glueing the lid. We need a bottom to go with the sides. I measure the cut side pieces where the dado runs from miter to miter and subtract 1/16"-1/8" depending on the size box and thickness of the side material. It makes for a nice tight bottom in plywood, and the slightly smaller size allows for a little wiggle room when glueing up the piece if a joint needs tweaking to close it.
Next, dry fit the bottom and make sure all of the miter joints close up. You don't want to find a problem after the glue is on the pieces. The best way to ensure a perfect miter is a shooting board and hand plane. I just use a tiny thumb plane to knock down ant high spots affecting the fit freehand. If you cut the miters at slightly less than 45 degrees(I use 44.7 on the tablesaw), the outside edges will almost always close tight and any error will be on the inside where it is harder to see.
Preparing for the glue up is the next step. I like to lay out everything as in the picture above. The boards in the series they go, band clamp ready with enough band already pulled out, glue, brush, and some paper towel to wipe up with. I place the boards on wax paper to ease cleanup. You may notice I am doing this on my tablesaw, and there is a reason. The front edge and the miter slot make a great reference for making the box square right after glue up. You don't want a trapezoid!
Glue up may now commence. Apply glue to all miter cuts or you may end up with a failed joint. Place a bead of glue in the dado for the bottom in each piece. Solidly glueing in the plywood bottom will strengthen the box and make it quieter. Now, assemble the box as it will sit when finished. I use Tightbond II and the open time has never been a problem. Wipe up any glue from your fingers as you go or glue prints will be all over the wood. The band clamp can now be put on, but don't apply to much pressure yet. Test for square against the miter slot and front edge, or the corner of your workbench if it is perfectly square, and apply more pressure with the clamp. You can now start checking opposite corners for square. If the measurements are identical and one corner is perfectly square, then the whole box should be square. A word of warning is in order about thin wood. The band clamp can cause the sides to actually bow in or out; so check these areas to make sure they are staying straight. A clamp can be used to bring in a bow out, a spacer could be used to push out any bow in, or you may just need to ease off the clamp pressure. You can now clean out the glue squeaze out. It is one reason I leave the top off for later. Measure the length and width of the box now for the top. We will make it as the rest dries.
I cut out the part of the board that is for the top to the dimensions I measured from the glued up box. I decided to resaw the portion of the board I chose for the top to make the lid since it was long enough for the planer. You MUST make sure this board is jointed flat or the box or lid will warp out of square no matter what you do. The final thickness is 3/16" and the thinness combined with the small width size meant I could glue it to the top. A thicker board or wider top may have had issues if I built it this way, and if you use a thicker board watch out for the weight. You don't want a box that falls over when you open it. I have another word of warning about snipe. If you resaw a top, it must not have snipe on the glue side or you will have an unsightly gap at the sniped ends. You can either make it long and cut the snipe off, make sure snipe does not happen, or make a shallow pass on a jointer to 'plane' the snip out. Once the board is the size of the box and the thickness you desire, we are ready to glue it up. Lay out all the clamps you will need and apply glue to the box top edge and the lid edge. Carefully set the top on the box and clamp it well. It should look something like the picture above. Part 3 will be about finishing up the box. I hope this is helpful so far.
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