Hans Wegner's "Bukkestolen" #2: Leg finger joints

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This is part 2 in a 9 part series: Hans Wegner's "Bukkestolen"

I think that the row of finger joints between the arm and leg is a perfect example of honest design.  The joint provides incredible strength to the arm/leg assembly, and Wegner did not try to conceal it.  In fact, I think he celebrated it, given the width of the joint.  It's a very distinctive and necessary part of the design, and I'll try to replicate it the best I can.

I have a second-hand Leigh D4R jig, and I've not used it for finger joints yet, so this will be a first.  I'll use a finger width of 1/4", which seems very close to the spacing of the original and allows me to duplicate the total of 13 fingers across the joint.




I found out that the Leigh jig was not intended to work the way I needed it to for this particular project.  Fortunately, I was able to work around its limitation.   My issues were:
  • It's not able to center the finger joints along an arbitrary width joint.  It's meant to work with material sized in multiples of the finger width only.  In my model, I wanted the outside fingers on the arm (and corresponding shoulders on the leg) to be slightly wider than 1/4" to allow for beveling later.  This shortcoming is due to the fact that,
  • The jig only has a fixed fence on the side to index the work against, and it's a pitifully small fence at that.  I ended-up using a spacer against the fence when cutting the fingers on the legs to achieve the centering.
  • The jig is not equipped to cut fingers at anything other than 90 degrees to the face of the work.  The legs need fingers cut at 7.8 degrees off normal in order to seat against the curve of the arm.  I solved this by installing a 7.8 degree wedge against the clamping surface of the jig. 

With at least having worked out how to cut the fingers in the legs, I first started setting-up the router and special guide bushing to get the fingers fitting together snugly.  I used some scrap 2x4s sized to the target width and thickness, followed the great Leigh setup instructions, and the first attempt was right on the money.


With that done, I made the small wedge mentioned above for the work to rest against.  The thin end cut off of the edge I inverted and taped to the clamping bar.


I glued a 1/8" plywood spacer to the side of the wedge.  This would then register against the tiny fixed fence to shift the work to the right the required amount.



Then a trial run on the scrap wood.  After a little trial and error, I was getting the results I wanted.   


I'm using red oak for the chairs, from the same stock as I used for the media cabinet project.  It's got a bunch of old borer holes.  I have to embrace them and say they'll add character.

I planed all the leg blanks to 1" thick and cut them to 3.5" wide.  I cut the 7.8 degree bevel at the top end and left them long in case there were any catastrophic errors when routing the fingers.  I could cut off the error and start again.



After loading-up the first oak blank in the jig, I found that it was slightly off-center, so I tweaked the position of the comb a little, and then made the first cuts.   


While the jig has a dedicated 1/4" spacing comb, it's too shallow to cut the 1" material.  Fortunately, you can use the 1/2" comb using a 1/4" bit, cutting a first pass, then sliding the comb down to position for the second pass.   An index pin through the comb into the stationary spine sets the spacing exactly.  Here is the result after the first pass. 


When I went to slide the comb to position #2, I found that my last-minute fiddling to center the comb over the work left too little room for the comb to slide fully into position.  The right side of the comb was hitting the stop at the end before the position #2 hole could move fully into place. 


After kicking myself, I thought about it for a while, and decided I could remove the comb without disturbing the settings, and file down that right edge to give it a little more room to slide.  It was kind of a pain, but it worked.


Crisis averted, I completed the final cuts.


With the fingers cut for the first leg, I repeated the process for the remaining legs.  This time with no problems.  Because of the tiny fence, it was easy to be off-plumb when clamping-in a new leg blank.  I had to check for square against the bottom of the comb and adjust for each leg before starting the cut.  I'll need to work out a better way when cutting the arms.


The diligence paid off.


Checking fit with a pair of legs.  So far, so good.



i agree totally about how he embraced the joinery. i love furniture that shows it as opposed to store bought where they try their best to hide it. great job on figuring out the angled box joints, looks great.

working with my hands is a joy,it gives me a sense of fulfillment,somthing so many seek and so few find.-SAM MALOOF.

Nice work getting the fit Ross👍
I have a D4R and am saving your fence and wedge tricks, neat ideas!

I've never seen a comb like that for the D4R, I just have the adjustable fingers on the bar.
Nice job taking the jig to the next level! The finger joints look great.
Thanks, all.  Splinter - I think that the finger joint comb was sold as an accessory or add-on.  I bought the D4R and the Leigh mortising jig from a guy who wasn't using them anymore.  I took whatever he had to give me, which included the finger joint comb.
Very nice writeup Ross! I don't own a Leigh D4R jig. So my approach would be totally different. I like the design though. It's certainly encouraging enough to duplicate. 
Thanks, Rick.  I believe that a table saw finger joint jig would have made it simpler to deal with the angled joint.  But since I had the D4R, I was determined to make it work.
Fine solution, and great to see that you had the courage to alter your jig to suit your needs.
I have made angled finger joints several times using a table saw sled (Matthias Wandel style), and there centering and adjusting spacing is super easy. But the end result looks great. 

"The good chair is a task one is never completely done with" Hans Wegner

I may have to build sled like that at some point.