Woodworker's Journal fall-2008, страница 84

Router Mortising Jig

THIS FAIL-PROOF JIG WILL CENTER A MORTISE ON ANY SIZED EDGE EASILY AND ACCURATELY.

by rick white

There isn't much to this jig, but it's been one of my favorites for years. It's a mortising guide that automatically centers itself on The edge of just about any board. With it, you'll cut perfect mortises every time, right down the center of your work-piece. All you need is a plunge router and a straight bit with a diameter that matches the width of your intended mortise. Clamp a piece of plywood to one side of your stock, and you can even form an off-center mortise.

The jig is just a simple, 3/8" thick Plexiglas™ router base, with ten holes drilled in it. Two of these holes are occupied by 5/16" bolts that hold 5/] 6" I.D. bearings in place with the help of a washer and aircraft nuts. The bearings straddle the workpiece and in turn, center the bit on it. They can be moved to any set of mated holes, to accommodate various board thicknesses. Three holes are used to mount the base to the router, and the last hole is for the bit.

To change the width of a mortise, just change the bit to one of a different diameter. You can even leave this base on the router permanently as a replacement for the original base if you wish. In that case, just remove the bearings when you're performing other tasks. For such a simple jig, it's amazing how often I find myself reaching for it

t*

1/4" plastic

Drill extra bearing guide holes closer together for mortising narrower stock. This allows you to get closer to the ends of a board.

Symmetrically placed bearing holes increase . your mortising options.

Router bit hole.

Drill countersunk holes to match your router base.

84 ArtS & CrAFtS STYLE SiDE TABLE

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