I had an upcoming job requiring almost 30 slab doors, ¾" panels, ⅜" solid edge banding, four sides. I needed curved cauls of several different lengths of for the glue up. Two issue presented themselves. How to get the ideal curve for each length, and how to produce a bunch of them quickly. The methods involving hand planes, bandsaws, jointers, and sanders did not appeal to me, to much futzing. I wanted a setup that was repeatable and didn't involve a lot of individual handy work.
Steve Elliott describes how he bends and marks the stock for the curve, but he then shapes it by hand. Good on the curve but not the shaping. Wes Grass, post #10, cuts his while still bent. Now we're getting somewhere. {On Wood Central - Moderator}
In my shop, jigs are made from scrap, cobbled together with staples and sheet rock screws. If glue is involved, it's hot glue. They are made for a specific task and are pretty much a temporary fixture. After it's used, it gets cut up and trashed. Rare is a jig that makes it on the wall.
This is the jig I came up with to repeatedly cut curved cauls on a tablesaw. The "sled" is ¾" ply with a ¼" ply support stapled to the underside.
The "clamp body" is a bock of scrap with a hole, screwed to the sled. The "clamp screw" is a ¼" carriage bolt with the head cut off, heated and bent. The bend continually straighten. Bigger would be better, or a better bolt.
Drill a hole in the middle of the stock, put a spacer at each end of the blank and tighten the "clamp" until the stock just touches the side of the sled. Notice the stock lifting off the ¼" base.
More scrap and a screw makes it sit back down.
Set the tablesaw fence for the narrowest width of the sled and stock (measured by the clamp), and run it through the saw. To be sure the blade trims the entire edge, scribble a pencil in the middle. If the pencil mark is still there, nudge the fence over and take another pass.
This is what the curve on one of my cauls. This method gave me the most even clamping pressure of all the other methods I experimented with. Another reason I like this is you can rework the same blank. For a 54" caul, I started with ⅛" spacers and work my way up to a ¼", using the same blank. I made two other lengths using different spacers. For 40" I used 3/16, and 28" was a fat ⅛", 4/5 oak. Your milage will vary depending on wood and size.
After the jig was made and the stock prepped, it took less than 2 minutes to shape each (virtually identical) caul. No, This jig is not hanging on the wall.
This is my first post here. I have used this site as a reference many times over the years. Just paying it backwards. Hope this is of help to someone.
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