It's so simple I'm thinking I must not understand the problem
I would certainly recommend the guide over the dowel centers
You still need the center points to locate where the hole should be.
Jim


Trying to drill new holes that will line up perfectly with the existing ones will be difficult at best, especially if you don't have a drill press. I'd be inclined to fill the old holes either by gluing in dowels or with wood filler/sawdust mixed with epoxy. Then I'd clamp the pieces together, all accurately aligned. While clamped, drill new dowel holes through the front and rear stringers, and into the end of the end pieces. Unclamp, apply glue to the mating surfaces reclamp and then drive new dowels through the front and rear stringers, into the end pieces. Reclamp as necessary until the glue dries. A bit of cleanup, sanding and whatever wood finish you prefer and you're done, except for caning, of course.I need to make a replacement part for a canoe seat. Cutting it down to size is no problem but I’m wondering if anyone knows a simple procedure to line up the holes for the dowels. I don’t have a drill press, just hand tools.
Thanks
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When matching a preexisting opposing hole, I use those insets Boatman pictured above to mark the location. These jigs can be either centered on the edge of the stock or offset as needed (the one on the left requires shims to offset). Amount of offset can be matched to an existing hole by first attaching the jig on that piece and adjusting so the bit lines up with that hole. A bradpoint bit in the respective hole is used to index the jig on the punch mark before tightening the jig. Of course, matching two new holes is simply a matter of measuring and marking. It's actually quite accurate, and entirely portable.Getting the holes straight freehand is always a challenge. I've used the guide on the right with great success, but I believe it's probably no longer in production. I recently found this Harbor Freight guide on the left that comes with threaded inserts for several increments, plus the two holes on the right for 7/16 and 1/2. Both are very adjustable. The HF one is easier to use for multiple centered holes, but the one on the right can be adjusted for thicker stock and off center holes.
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