On a treble bridge, most of us find ourselves edge gluing the several sections together, typically 3 to 4 pieces. Most people do butt joints, which is what I have always done. I'll share my latest method, but if someone has a better, simpler method I am all ears. I start by cutting the pieces roughly to length, usually having the joint at the space between the breaks. I establish the angles which will allow the grain line follow the direction of the bridge as much as possible and best spaces the bridge to the width of the piece, and make the angle cut. So on to the end. Of course these are not butt joints where the joining end pieces are in the same plane, but rather at angles of varying degrees. And there's the rub. Because the pieces are at angles, they want to slide away from one another if you simply clamp them and moreover, the pressure is not applied evenly and gaps occur too easily. I start by jointing the sides of the pieces so that each side is more or less parallel, and do this for each of the pieces. Since the pieces are not always of the same widths, I establish on the bridge where I want the two pieces to meet along the edge length and set up my jigs accordingly. The longest piece I clamp down to my work table in a couple of places so that it cannot move. I then take a rectangular piece of wood with a jointed side and butt that up against the outside edge of the cap piece and screw that down into the MDF table top with sheet rock screws, taking care that the cap piece is butting perfectly at angle to the other cap piece. I take another rectangular wood block and do the same on the other side of the cap piece. Then I butt a block of wood against the open end of the cap piece. Behind that I screw down another wood block parallel to first block, but with a couple of capstans screwed into the face of it to butt against the first piece and be there to apply the clamping pressure. Then I turn the capstans until I have very snug pressure. I also clampdown a piece of wood spanning the gluing joint. Wax paper underneath the joint and on top. This seems to give me pretty snug joints without gaps and a thin glue line. I have been thinking about using scarf joints as some do, but have not tried it yet. Anyone out there doing them? Below is a link to a clever jig for cutting 15 degree scarf joints on a table saw. It is accompanied by plans to make it. http://home.comcast.net/~kathymatsushita/amateurluthier/htmlpages/scarfjig.h tml Will Truitt -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20110712/eb1f09e1/attachment.htm> -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: image/jpeg Size: 4863 bytes Desc: not available URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20110712/eb1f09e1/attachment.jpeg>
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