ELM – Squirrely grain – different tactics
A fair amount of 8/4 elm stock found its way into the shop not so long ago. So I decided it was time to build a few stick chairs. Having been inspired in past years by the work of John Brown and, more recently, Jack Plane, I knew that the traditional seat plank material for these chairs is elm. So, the decision being made, I began the process of planing the seat plank true. The seat plank is the heart of any style “Windsor” chair.
The grain of elm can run in every direction and it is interlocking. These qualities make elm one of the toughest woods around. Traditionally, elm has been used for things like wheel hubs and livestock barn flooring. However these same qualities can make elm a challenge to work.
I started with a twenty-inch foreplane, well cambered, planing diagonally to bring the datum into plane. Once the winding sticks showed that I was in plane, I used a 4 1/2 with the iron cambered at about 5 thousandths of arc height. And if you look closely at the iron, you’ll see that there is a “+10” inked above the lever cap. In my shop this mark indicates that the the iron has a 10° back bevel, so this set up acts like a York pitch plane. It allows me to remove a maximum shaving thickness of about 3 thousandths. That’s enough for “rough” cleaning the scalloped surface left by the foreplane. This “quasi finish” planing is done on the diagonal.
The plank is flipped and marked for thickness. First passes are made with a scrub plane, on the diagonal. This is followed by the foreplane, to “ease” the very deep scallops left by the scrub plane. Then the 4 1/2 was used to finish the “show” surface. This final planing is done “crossgrain”. (The actual finish planing was done before the seat shape was cut, so the above photo is a little misleading. Cross grain planing will cause some edge damage, so calculate your rough width accordingly.) Many folks who are new to handtool use are unaware that much, if not the bulk of hand planing is done in this fashion, across the grain. Simply put, that’s why finish planes, used by the professionals of old, always have a little camber. You don’t leave tracks and you don’t tear and lift the fibers. Needless to say, the iron must be razor sharp for optimum performance.
Now for the real tricky part.
I’m going to saddle the seat, lightly. In pine, I’d probably start this job with a small adze then finish it with an inshave. But, due to the nature of the elm’s structure, I’m going to do it with all with very light passes of the inshave. If you look closely at the photo, you’ll note that the grain seems to follow the profile of the saddling. Well it does and that will add to the beauty of the finished product. However that adds a new little twist. I’m shaving crossgrain. But in certain areas I’ll be cutting “downhill”, only to encounter a change in grain direction, which will throw me into an “uphill” situation. There’s no “across the board” solution for this dilemma. The answer is that you have to look at the surface and change your cutting direction accordingly. You have to be “one with the wood” as Yoda would say. BTW, when using any type of shave, start on the bevel and find the minimum clearance angle required to give you the shaving thickness and level of control you need. And again, a shave must be razor sharp, or you might as well do this job with a power grinder. Stay tuned. This might turn into a pretty interesting project.