Not to do what I have done.
I know how you like to see me make mistakes. Made a doozy yesterday. I was having a great day making a JA chair, everything going swimmingly. Chopped the slat mortises, did all the boring and sub-assembly. Even brought Daniel out for the final assembly – it’s nice to have an extra set of hands and he seems to like the weird noises the joints make as they go together.
Then I blew up the front post. Sheared it almost in two, right in the middle.
Exit Daniel while I figured out what to do. “I thought you were supposed to be good at this…” I keep hearing that high school kid from years ago.
Oh well, a teaching moment. Of course it happened at the end of the day. So I didn’t really get blow-by-blow photos. First thing – get the broken post off those rungs. Before the glue hardens. This was yellow glue and it was late in the afternoon, so not hot weather. Time on my side there. I sawed it off above and below each set of rungs. Then split off the bits.
Then spoke-shaved and bored a new post. Put some glue in the mortises, wriggled it onto the side rungs, then drove that home. Then wriggled it onto the front rungs.
And split it to smithereens.
The culprit? Besides me, I mean. Slow-growing oak. Maybe too-tight joints. Certainly the first, maybe both factors. I’ve written a number of times about slow-grown oak – how much I like it FOR JOINERY WORK. Planes easily, mortising – piece of cake. Carves beautifully. But that oak furniture I make is greatly over-built. Jennie Alexander’s chair is designed to push the material as far as you can. So no weak wood there. I was testing my luck using these posts – and lost.
Those bits above are 1 3/8″ in diameter, more or less. The pencil marks are at 5-year intervals. The two on the left have just over 15 growth rings in them. In red oak, that’s a lot of open pores and weak fibers. the one on the right went in the chair successfully – and it’s still pretty dicey. 11 rings maybe?
Today I got a new post on the chair & it’s fine now.
And started in on a white oak chair with posts that have about 7 or 8 growth rings. Strong, just like JA used to use.
I was thinking about Alexander a lot – I had extra time on this chair. I remember her telling me years ago she wanted to call the book “The Fifth Post.” And then, when reading her old notebooks, I see that during the original photo shoot for the first edition, she put the rear rungs in the front section! Got them back out somehow and carried on. Well, the consolation is that it’s good to be ready for chair emergencies and to know what to do when things go horribly wrong. No one got hurt, that’s a plus.
PETER FOLLANSBEE: JOINER’S NOTES 
I would have flipped out.
Nah – it was very funny, in a pathetic sort of way. My own fault for using wood not up to the task. I need to start buying two different logs at once…one for joinery, one for chairs.
I don’t like to see you make mistakes but I do appreciate you sharing them with us. I’m not sure I would have thought of cutting up the leg and splitting off the mortised parts. I’m impressed you were able to end up with a stable chair.
Michael
I agree on all the above. It makes an amateur like me feel a little better about my mistakes when a much more experienced chair maker admit to his mistakes.
About to attach the top to my first joined stool. Good journey. Can’t wait for my next try. So much to learn and work on making better. Thank you for guiding me on the trip.
Don’t take this the wrong way but we love it when you make mistakes.
Richard Raffan is a well respected wood turner. I appreciate his view on mistakes that if you do a lot of woodworking, sooner or later you will make mistakes. If you push yourself to better quality or speed you’ll make a few more. Part of being good at your craft is how you recover from problems and not just how things turn out when everything is going perfectly.
Thank you for sharing how you approach this type of problem.
Nice work Peter :) I really appreciate this type of post so very much. As I make more of these chairs my mistakes are little calmer , I usually know there is a solution. Great work and thank you for sharing!
Darn.
I wanted to see what brand of blue epoxy you used to fill the cracks.
Great save and great post–
Wow, what a great post and I’m so glad you shared. As a matter of fact I built 6 of these chairs for our kitchen table as my first chair project last year as COVID therapy and loved them so much that I decided to make three for my woodworking club to do a demonstration that I’m just now finishing on my blog. What I find so fascinating is that each one creates a new set of small challenges, a small irregularity there, a start to a split here, can I fill a small crack with epoxy and wait and see……. So far none of mine have come completely apart so I’ll just see. But I’m really excited that you showed this post, because now if it does happen to me I won’t completely freak out. It actually gives me a tiny bit of hope that even if a chair leg split years from now it might be able to be repaired. Now here’s hoping I don’t ever have to find out.
Is that a ghost looking in your window?
Interesting that the oak with more growth rings, that we would normally think of as “stronger,” failed in bending parallel to the grain and long axis. I guess the oak with fewer growth rings, while not “strong” in the classical way we often think about it, allowed for the bending forces required to successfully assemble the chair. While I am certainly not an engineer, I think I have that right. Maybe an engineer can chime in on this. In any event, thanks for lesson in materials science Peter.
Hi George – Nah, we don’t need an engineer. But you have the strong/weak thing just ass-backwards FOR OAK and other ring-porous hardwoods like it, ash, hickory. More growth rings means more open pores from the early part of the growth cycle. Hence less dense material. Slower growing oak is stronger. Just the opposite of softwoods like pine from what I know of softwoods. I started the year with a post about this subject that includes a video of snapping some oak https://pfollansbee.wordpress.com/2021/01/12/slow-growing-oak-vs-fast-growing-oak/
hey Peter,
I might have the same problem coming up for some bends of old growth ash. the wood intend to bend is slow growth, but there seems to be fewer tyloses in some sections , so it seems like it would be tough enough to bend because of the density. ever have a similar experience?
thx!