Step 5 - Making Mortises
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 Today dear readers, we are cutting the mortises into which the tenons we fashioned yesterday will fit. I use a special attachment on the big drill press to cut mortises: The business end of this consists of a hollow square chisel with an auger bit inside of it. One side of the chisel has a slot in it where chips are ejected. Essentially, it drills a square hole. Drill a series of square holes next to one another and you have a mortise. There is an attachment on the table that helps to hold the work piece so that the mortise is square with the piece and the proper distance from the edge. More or less; that's where the skill comes in.
 Once a mortise is cut, I go in with a sharp chisel to clean out the fuzzies and square the bottom corners. Then I test fit the pieces together, if they're too tight, I can shave more out of the mortise or sand a little off of the tenon -- or both, depending on what the situation is. There are a lot of considerations to keep in mind, and one must work carefully and slowly so as not to take off too much. It's much harder to put some wood back than it is to take a little more off. So I shave a little, test fit, mark where it's too tight, shave a little more, repeat until it's right.
 Here is a nice snug fit. The parts should slide together with firm pressure, but not need to be hammered home. Too tight means that when glue is applied and the joint assembled, the wood will swell up some and the joint will not go together without excessive force. Excessive force tends to break things. Too loose and the joint will not bond together. Glue may be able to fill the gaps in a loose joint, but most glues (aside from Epoxy) offer no structural strength; the first time the joint is stressed, the glue will begin to crack and crumble and eventually the joint will fail. But if the wood in the joint is in firm contact, the glue binds the two surfaces together in a bond that will last for generations.
 After a morning of fussing and fitting, the back frame is complete. There is no glue in these joints, for we still have more to do to them; this is just the first step, But the frame can easily be picked up and carried around without fear of anything falling off.
 By the end of the day I've complete the two doors and two side panels as well. Two more side panels need to be done tomorrow, then we'll get groovy.
Man Hours: 10¼
Materials: None
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