Coopered Joints

Coopers rightly frown if you call them barrel makers. Staved containers come in all sizes, from firkins to hogsheads, with barrels somewhere in between. Coopers have the longest plane of all (as they are quick to tell you). The five- or six-foot-long cooper's jointer inverts the relationship between work piece and plane. The cutting edge of the cooper's jointer faces upward, with one end of the plane resting on the floor while the other end is elevated on two legs. The cooper stands beside his inclined plane and pushes the stave down it. The cooper works by eye, holding each stave at the precise bevel that, when repeated on the other staves, adds up to a perfect cask.

In one sense, the cooper has it easier than the rest of us. The angle of the edge of each stave is always the same — 90 degrees. Before taking a stave to the jointer, the cooper first backs it with the drawknife to the contour of the cask. The back of the stave is a segment of a circle, and the correct angle for the edge is perpendicular to a tangent of that circle — always 90 degrees. No matter how wide the stave, eyeballing a right angle off the edge of the circle gets you a perfect stave. Repeat this a few thousand times and you can get very good at it.

Coopered work for the joiner includes items like porch columns and rounded tops for chests. The process for joiners is the inverse of that used by coopers. You start with rectangular stock, bevel the edges, glue it up, and then round the outside. The bevel of each edge is half the angle between the faces of the stock.

You can always make a full-sized drawing on paper and take the angles from that, but if you're working mathematically, divide the 360-degree circle by as many staves or facets as you will use. With 8 staves, this would come to 45 degrees, so each stave has to cant 45 degrees off from a straight line (180 degrees) to turn its part of the full circle. We're concerned about the inside angle, however, so this is 180 degrees minus 45 degrees, or 135 degrees. Half of that is 67.5 degrees. Any 8 staves of equal width, then, with edges beveled at 67.5 degrees will form a complete circle, or, rather, an octagon that can be planed into a circle.

Once you know the angles, you have to plane them accurately and consistently down all edges. The try square gives you a fixed 90 degrees, but the sliding bevel can be set and locked at any angle you desire. Set at 54 degrees for a five-sided object, the sliding bevel will test the edge angles as you plane the staves. The width of all staves needs to be equal as well, so you can't just keep planing if you make the angle too steep. Often, you plane away too much because you can't see when to stop. A pencil squiggle down the edge will help you judge your progress and tell you when to quit.

Sliding bevels (not all bevels slide, but I say sliding bevel when the tool might be confused with the shape) are especially useful when you're making a piece to custom fit an existing angle. In a hopper-sided tool tote, for example, you can join the sides at whatever angle looks good. With the sliding bevel, record the resultant angle and then use it to test your planing for the inset bottom board. You have no idea what the angles are, but it all fits perfectly.

For work that you are going to do more than once, it's better to use the sliding bevel to make an accurate planing guide and use that for all the staves. A regular shooting board holds wood parallel to a ramp where the side of a plane can ride. Like shooting end grain in the bench hook, this puts the edge of the plane at 90 degrees to the face of the wood and ensures that its edge is square. If you want the edge at less than a 90-degree angle, say 54 degrees, then add little 36-degree ramps to tilt the staves down into the plane. The angle left on the staves will be 54 degrees, and your five-sided column will join the pantheon of pentagonal paragons.

Once set, this sliding bevel can guide your planing to fit a tight bottom for this tool tote.
Trim around the edges of the holes in doweled joints before gluing.
The shipbuilder's pegged, free tenon hides within the planks.

This is another place for the rubbed glue joint. Rather than trying to glue up the whole thing, work on pairs, allowing each pair to dry before setting up the next. For longer work, clamping is not possible without gluing on temporary blocks to give the clamps a place to grab. Instead, make cradles of two stops nailed to a board, spaced so the staves can sit within them, tentlike. If the spacing of the stops is just right, the joint can be rubbed while sitting between them and weighted until the glue sets up.

Woodworking Tools and Installation Tips

Woodworking Tools and Installation Tips

There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.

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