Making Riven Wedges for Tenons

Building this staked Roman workbench was another opportunity to do one of my favorite woodworking operations: riving and paring wedges.

I started with white oak that I’ve had sitting around since building my “Roubo” lathe (seen in the banister-back chair article) last year but any straight grain bone-dry hardwood would do. With a mallet and hatchet (a wide chisel also works), I split off several pieces about a ¼” thick. This only took one moderate ‘thump’ per piece.

With my four pieces split, I placed each in my wedge shaping block. This is nothing more than a notched shelf on a block held in my front vise. I’ve seen Windsor chairmakers use a block like this but I’m not sure who the first one was to use this. I love this little appliance. Until now, I had always used my bench hook for this operation. It worked fine. The fact that it got pretty hacked up didn’t bother me - It was just too long to pare comfortably at a low enough angle. Also, it was a bit awkward at the low height of my bench top. This paring block is much more comfortable to use.

I didn’t try to taper the whole 2” wide wedge in one pass. I tapered each face of the wedge by paring one edge, then the other, followed by a final pass to clean up the hump in the middle. I tapered to half of the thickness and flipped it over to pare the other side to meet it.

A word on safety here: A sharp chisel is the most dangerous tool in your hand tool shop and it would be easy to make a mistake you’d regret. To avoid an accident during this operation, keep both hands behind the edge. That shouldn’t need to be said but it’s tempting to put your other hand out in front. Also be careful to not lean all your body weight into the chisel. If something slips and you are leaning too hard into it, your momentum is going to send you tumbling into a loose chisel. You would have a mess on your hands – literally. Always make sure you reserve control to stop yourself if things slip. You always want your momentum working for you but not at the expense of your safety.

I didn’t bother paring the last bit of the thickest end because I made my wedge intentionally longer than I needed. it’s harder to start the chisel at the very edge of a blank so I made it a bit longer than necessary to eliminate any fuss.

Wedges this big should take no more than one minute apiece. In the flow, it really is less than 20 paring cuts with the chisel. Smaller wedges (say ¾” or 1”) can easily be made in two paring cuts.

You don’t need to buy wedges and you don’t need machines to make them. I used to spend time sawing them out by hand in the end of a board but no longer. Straight grain is a real advantage and this riving method will give you the best wedges money can’t buy.

 - Joshua