Jig Saw Straight Cutting Jig

As promised, this is the straight line cutting jig for use with a jig saw. I'm acutally making a 24" long guide here, as I use other tools to cut longer staight lines, but I wanted to illustrate the process here. Go to your lumber store and get 1 piece of 1/4" or 3/16" hardboard 2'x4' and 1 piece of 1/2" MDF or plywood, also 2'x4'. Ask the store to rip an 8" wide piece from the hardboard, and a 4" wide piece from the mdf/plywood.  Be sure and take the offcut as well, because you can use them to make different length jigs, once the first one is made. I recommend you have a jig 48" long so you can crosscut a full 4'x8' sheet of plywood into whatever length you need, and another jig 18-24" long for shorter crosscuts and rips. While you are at the store, be sure to get at least 8-12, #8 x 1/2" long screws as well. You should leave w/a piece of hardboard 8" x 48" and a piece of mdf/ply 4" x 48". Mark the factory edge of the pieces you just had cut, because these will be your reference later. Once you get home, put the mdf/ply on top of the hardboard and align the factory edges so they are even. Clamp the boards together, predrill and countersink for your 1/2" screws. I placed my screws about 1-2 in from the edge, and about in the middle of the mdf/ply. Put screws on both edges, and about every 12-16 inches the length of the mdf/plywood. Be sure to keep the edges aligned as you drive the screws. Once you have screwed the pieces together, use your jigsaw to trim the excess hardboard off. Here is the jig, partially trimmed. The great thing about this jig is that is will be perfectly set up for your tool, no measuring required! To use, just measure and mark the beginning and end of your cut, line the edge of the hardboard up on the measured lines, and cut. By keeping the edge of the jigsaw shoe against the mdf/plywood lip, you will cut a straight line every time, as shown in the next picture. No measuring, no stress, just line the jig up and go! The board in this picture was cut exactly 6 inches in width, and was less than 1/64th of an inch wider at one end than on the other. That's plenty accurate for me! For larger views of the pictures, you can go to the flickr stream for this at: http://www.flickr.com/photos/5.....8/?saved=1

Joe