Twist and Shout!

A little while back we were twisting the 3/4" thick by 2" wide by 34" long white oak slats to make up Dining Table No 1. We were doing this with kiln dried wood, which typically speaking doesn't steam bend all that well, but given that the most extreme twists for the table are around 45 degrees we tested it out, and it seemed to work without any problems. After one long day and some 70 slats twisted and clamped to the metal base to dry we decided to "test the limits" with the few that remained in the steam box. The slats were steamed for roughly 2-3 hours at 200+ degrees fahrenheit, the results were pretty incredible, to watch the bending happen check out this video.

The Indestructible Miter

Before you get into this, I am sorry, this post is long, it may or may not make a lot of sense, and I am sure a lot of people would argue with what I have said. Carry on. Indestructible miter. A bold claim I know. Indestructible and miter are words that do not often go together. The miter opened up, this mitre won't close, why did I choose to use these damn miters, all a lot more common to hear.

But bear (bare?) with me here, what you are about to see below is an adapted version of a joint that was introduced to me as "the indestructible miter." Or if you would like to take it down a few notches on the "awesome scale" the plywood L-tenon. It is exactly as it sounds. Plywood and indestructible are again two words we are not used to hearing together, but it is the perfect material for an L-Tenon.

Why you may be asking? Alternating grain direction for maximum strength. It is really just that simple. Miters are difficult to join because of the amount of end grain in the joint (end grain has no glue strength). This is why typically we cut keys or splines in a miter joint is to gain some "face grain glue surface."

But isn't half of plywood end grain? Sounds like you are going against your own advice....

You got me, it's true, but the other half is perfect face grain to face grain glue surface. And the end grain portion on the one side of the miter is the face grain on the other part of the board. Tricky no?

But there's another part to this equation. Keys / splines and most other miter "joinery" has very little "depth" into the actual boards. This may be okay for little boxes, or a casepiece, but chairs are under stress, a lot of stress, and they need something a little more substantial. The "L-Tenons" allow me to route deep (in this case around 2") mortises into both parts.  What I end up with is a 2" worth of tenon (and a longer bit could get me more) into either side of the miter. Quite a bit of depth all things considered. Couple this with the alternating grain and you have a joint that is "indestructible," relatively speaking anyways.

This may be a lot to take in at this point, hopefully the pictures will clear it up some. For the record these are a bit of a variation on your standard "Plywood L-Tenon" as they are obtuse angles and canted as well. Testing as to the actual strength will commence once the stool is together. Stay tuned.

Drawing and Reality

So with the mock-up complete for Bar Stool No. 3 it was time to move on to a more detailed full scale drawing. Below is a drawing that the more I tried to simplify it the more complicated it appeared. The result was my brain getting pretty mushy and working on something else for the morning (see the post about dodecahedrons). In the end I needed to trust the angles and dimensions I had laid out and went to cutting the compound mitred frames that will make up this stool. The picture at the bottom is with the angles cut and pieces of tape wrapped around the outside of the miter to see how everything fits together. I should have been able to visualize this from my drawing (maybe?) but was pleasantly surprised when I began piecing the parts together and revealed the "double mitre" joint that will be visible from the back of the stool.

 

Mocking Up Bar Stool No. 3

While co-teaching the chair making course at the Center for Furniture Craftsmanship I got an opportunity to design a speculative piece, something I rarely have the opportunity to do throughout the rest of the year while commissioned work is on the go. Below are pictures of the first mockup for a new bar stool design. I usually begin my design process for seating objects by going from a sketch to a full size drawing. The full size drawing doesn't need to be complete from all views, but at least have basic dimensions, shapes and angles roughed out. I then make the first mockup with whatever materials are lying around, in this case plywood, poplar, screws and hot glue to get a rough idea of proportions, shapes, heights and angles. The mockup is a tool used to go back and refine the drawing, see the idea in three-dimension and begin to work through what the construction / process of the piece might look like. It's always best if you can sit in the mock up to gauge comfort of heights and angles, sometimes additional props or stilts might be required.

Things I learnt from this mockup....

I felt the weight of the legs was a bit heavy, so they have been taken down in dimension on the first iteration. Part of this might be the thickness of the plywood seat I had available which is a bit thinner (lighter) then I have planned. I also wasn't a fan of the seat sticking out past the back legs, so that has been reworked. The footrest has been raised, and the front legs have a wider stance to give the seat some splay which will be more cohesive with some of the other tapered forms found throughout the piece. Now to sort out the construction...

Let the twisting begin!

Dining Table No. 1 is going to consist of 66 twisted wood slats twisted to 16 different angles. We are using 3/4" thick kiln dried white oak that will be steamed at 200+ degrees fahrenheit for around 2 hours. Here is a video of the twisting in action. Clamps, we also needed a lot of clamps, seriously.

Dining Chair No.6 Awaiting Pickup

Recently finished the run of Dining Chair No. 6 with a matching bench. The version you see are about 1.5" taller then standard to accommodate a tall family and accompany a 33" tall dining table (3" taller then standard). Made from local black walnut with black leather upholstery.  

Marilyn?

Setting up to take some photos of the Dining Chair No. 6 mockup.

Snapped this Marilyn Monroe inspired shot by total fluke while adjusting/testing the settings on the camera.

Timing is everything, better to be lucky then good, isn't that what they say?