Benchtops

When I started working on a bench design, I was all in on Roy Underhill’s french bench that I saw on the Woodwright’s shop and in his book The Woodwright’s Apprentice.  For those of you that have never seen this, here is part I of that episode.

I was totally sucked in by the angled legs and the awesome sliding dovetails.  But this bench was solving a problem I really didn’t have.  It was designed to use a “smaller” solid benchtop when compared to the traditional Roubo-style bench.  I was planning on laminating my top, so my benchtop was limited only by my ability to move the glue-up around.  Before I recognized this, though, I went ahead and laminated up a top.  This was also before I was really committed to handplanes and before I had my dewalt thickness planer.  That glue-up was done with the “as-ripped” boards.  It turned out OK, at best. Here’s an end pic of that top

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These are ripped down 2X6’s and kinda knotty.  You can see gaps where the cup in the boards prevented me from clamping them completely closed.  But it will work.  I glued up the second split top using sections I ripped from a 2X12 and ran through the thickness planer.  This top is significantly better than the first one. Both in terms of the quality of the wood and the quality of the layup.  After gluing them up, I flattened one side with my jack and jointer and then ran them through my thickness planer.  That was fun.  Really.

Drawboring and Bolting

Working on a large workbench in inconsistent 2 hour periods at night is a sure-fire way to make slow progress on big projects.  In the last post I got the base together.  It’s now drawbored and bolted.  Here some glamour shots of the drawboring and the bed-bolt arrangement I went with

One thing that I failed to realize is that I should have made the oak pegs oversize for the 3/8 hole I drilled.  The pegs tend to twist and bend as they are driven home and open up little spaces at the edges of the holes.  I followed the PW guide on drawboring here, but neglected the pin shaping suggestions (other than adding a taper).  They look OK.  The end units are crazy solid.

I then drilled the counterbores for the washers with a forstner (same one I used for the mortises) and used the center point of the counterbore as a starting point to sink a 1/2 hole as far into the stretcher as I could.  I then disassembled the frame and drilled the stretcher as deep as I could with my existing bit.  If I had access to a drill press, I would have drilled the leg holes with the press to make sure that they were vertical and then used those holes to freehand the stretchers.  As it was, all the holes were a little angled, but it didn’t seem to matter.

Once these were drilled, I used the forstner to drill the crossbores and used a chisel to square up the resulting hole.  Everything pulled together at that point and is super solid.  The bolts were 8 inch long 3/8 bolts from the home center.  Next up, gluing up the tops and flattening them.

Progress & Dowel Plates

Augering through this, so to speak.   I am clocking about 30 minutes per mortise at this point, however things sped up a lot when I remembered that I had a 1 1/4-in chisel floating around my tool chest.  I also ditched the spur auger and switched to a forstner bit in my 1/2 in drill.  I didn’t think you would be able to use a forstner in a hand-held drill.  But you can.  Here is the base all dry fit and looking ready to go.

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Now that the mortises are chopped and the tenons fit, I’m moving to drawbore the joints on the two leg modules.  Since the 3/8 dowel stock at the home center is not 3/8 in diameter, I bought 1/2 in rods and pounded them through my home-made dowel plate.  I made this out of a scrap piece of 1/4 steel I had lying around.  I add a little bit of relief by back drilling with a slightly larger drill after I drill the correct size through the plate.

Here I’m drilling through the plate.  I sized the holes in 1/16 increments from 9/16 down to 1/4.  I had used the 1/4 before for pegging the breadboard ends of the dutch tool chest.  After each hole is drilled, I flipped the plate, used the bit to center the milling machine in the hole, and then swapped out for a larger drill.  For the 5/16 hole I used a P drill, which is a little over 0.01 oversize and I kept that general rule for the rest of the holes.  The exact dimension probably isn’t import, you just need enough clearance to let the dowel drop through without a lot of effort.  I chose the 0.01 oversize because I could easily see the ridge that the drill leaves.  Here’s a shot of the ridge after the back drilling (which really isn’t an actual term, but I think it’s pretty descriptive).  If you look closely you can see a small ridge in the hole.  That gives me the clearance that I’m looking for.

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This process is really easy in a bridgeport mill.  You can do it in a drill press, just make sure that you have a vise and then shift the vise around to line up the holes.  Then lock the vise down to the table and drill on!   You have to be careful because the drill will want to grab and pull itself into the hole.  You can easily drill all the way through if you’re not on your toes.