After examining many, many workbench designs and almost settling on a German-style bench, I came across the 17th century French workbench of Andre Roubo. This design seemed to have surpassing versatility and an aesthetic superiority to every other design. In the construction process I learned of the trade-off between functionality, design, and ease of construction. I have made awkward-looking workbenches in one day which function perfectly. I've also made beautiful tables quickly and easily which are only useful as buffet tables. To make this workbench functional and attractive required that every surface be planed properly, and every corner be a perfect 90 degrees.
Step 1: Some Large Pieces of Wood
The legs and stretchers are reclaimed old growth Douglas fir. Though mine were salvaged (and thirty winters have hardened these beams nicely), here on the West coast, 6"x6" Douglas fir is a standard dimension. But finding a mass of wood for the top that's both deciduous and contiguous is a taller order. The top of a workbench should be hard. Exactly how hard depends on a few factors; if you're going to be working primarily with hard woods, then your bench should be hard enough to take some use but not so hard that it might mar the wood you're working. It's better to dent your bench than your workpiece. For my bench I opted for poplar wood, as it's harder than pine but still affordable (kind of). By happy coincidence I found a supplier selling it in 3 1/2" thicknesses*, which fits the leg joinery perfectly (the final beams were 3 1/2" x 5" x 72"). To keep costs down I used a reclaimed beam of glued-up Douglas fir for the middle 13" of the top. Since most of the work on a bench takes place around the edges I saved the hard wood for that area.
*My original intent for this project was to use only reclaimed wood I could get for free. Though I ended-up purchasing the poplar beams, I think sitting in my garage as long as they did before I completed this project qualifies them as reclaimed wood.
Step 2: Tools
Of Japanese saws I can scarcely speak highly enough. The narrow, self-straightening blade has replaced my western saws for most straight cuts.
A brace and auger bit makes easy work of hogging-out mortises which can be cleaned with a chisel and mallet. I use a rubber mallet which is easier on the tools and the ears and I haven't noticed much of a difference in efficiency using a solid wood mallet.
These tools or acceptable analogs are available at TechShop.
Step 3: Joinery
The outside of the legs must be completely flush with the edge of the top slab. This allows the entire side of the bench to work as a clamping surface but is a difficult feature to achieve. I intentionally made the legs a quarter inch too thick then planed them down after being fitted.
Step 4: Legs and Stretchers
Everything was dry-fitted several times before the final assembly, wherein I used drawbored dowels and urethane glue. A larger bench might need to be broken-down for relocation, but at 72"x20", heavy as it is, I can move this around if I need to.
Step 5: Wedge Issues
The through tenons on the top are cut slightly narrow so the joints must be made tight by adding wedges. I cut the straightest-grain scrap I could find and coated each in glue before driving them home.
Step 6: Cut and Plane Again
Pictured is the wood nut for the leg vise, detailed here.
Step 7: Adding the Hardware
Step 8: Turning the Knobs for the Tommy Bar
Step 9: Holes
To make my dog holes straight and perfectly verticlide, I first tried using an angle guide on my cordless drill (I don't have Forstner bits that fit my brace drill). Due to poor manufacturing, the guide didn't work. Plan B was to make a bit extension using the lathe at TechShop and guiding it straight by use of a square. I clamped a board to the underside to prevent tear-out when the bit breaks-through
When the battery died I switched to my brace drill which I should probably have used from the start. Once inside the wood the flutes guide the bit straight down. I had preferred to use a Forstner bit since it makes slightly cleaner holes, but I had to sand each hole clean to get a perfect fit for the bench dogs so the brace was as good a choice. Also, the auger bit evacuated the waste better and didn't get as hot.
Besides the series of dog holes, I drilled four more holes for use with a holdfast or other workholding devise. These should be placed such that the holdfasts can have the most effective reach across the surface.