Roorkhee Chair v. 2

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My original Roorkhee chair was comfortable, but it was very low to the ground and deeply reclined. I prefer a more erect seating style, and thought I might raise the chair and make it less tilted. This proved to be considerably more difficult than I anticipated. It was easy enough to test the effect of taller legs by putting the first one up on blocks, but what happens if I decrease the seat tilt? I made some new back legs in pine with holes in different spots for testing and I found that raising up the back to make the seat more level wasn’t enough by itself. It wasn’t comfortable like that. It needed some other changes like a decrease in seat depth. I didn’t have a good way to prototype that. Decreasing the seat depth also leads to decreasing the width (if you want to keep the frame square to avoid complicating the assembly) and it’s not clear that would be a good thing.  In addition it seemed like the location of the pivot point for the back rest needed to change.  What seemed like a small change to the design turned out instead to requires global alterations.  So I gave up and made a chair whose seat is farther from the ground, but with no other changes.

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Another change with version two was the choice of leather. For the first one I used discount leather. That leather was too stretchy, especially for the arms. So this time I took a look at leather from Wickett & Craig, which Schwarz had used in some of his later chairs. Schwarz used the Oiled Latigo, but when I looked at the samples, all of the oiled Latigo leathers were almost black. I ended up choosing the English Bridle leather which is apparently the same leather, not oiled. The Latigo comes in a 6-8 oz thickness but the English Bridle is not split, meaning the leather comes off the cow the thickness it is. I could have paid an extra $1.10 per square foot to have it split and re-dyed, but decided to go ahead and use it as it came in a 8-10 oz weight.

One problem with the original Roorkhee was the narrow width of the arms. I noticed that I would try to rest my arms on the arm rests and they would fall off, so I corrected that in this version with arms that are wider.

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The wider arm rest is definitely an improvement.

For the first chair I cut the leather and put it on the chair. But I subsequently learned about finishing the edges, which definitely produces a much nicer look. To do this I first beveled the edges with a leather edge beveling tool. Then I applied burnishing compound and burnished the leather vigorously with a leather burnishing tool. Finally I applied edge finish to the burnished edges.

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The top edge is rounded and smooth after burnishing and edge painting.

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The roundover on the front edges was intended to make the backrest more comfortable, though the leather is so stiff that it may not matter in this case.

For this chair I made the legs from canarywood scraps I had on hand—the only 8/4 material I had enough of. The wood is pretty, but I think it is harder than the ideal for hand powered reaming. (It is a good bit harder than hard maple.) I had more trouble cutting the mortises than on the first chair, and the finished joints were worse. I used maple dowels, and I ended up making the back supports out of some bland apple sapwood. From sitting in the original chair I had noticed that my shoulders and back would rub uncomfortably on the edges of the backrest supports, so for this version I was careful to give them a big roundover, though in the end it may not have mattered so much because of the heavy weight of the leather.

Here you can see the process of folding over the leather of the back rest. On the first chair, this part of the project was a little irregular, so I took more care this time, making measurements, keeping everything parallel, and clamping the pieces together before making the holes for the rivets. As it turns out, this particular measurement produced a very snug fit with the stiff leather I was using.

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I determined the fold for the seat back by clamping the rail flush with the edge and folding the leather over for a snug fit. I marked the fold, removed the rail, and then clamped the leather down to punch the rivet holes.

The original design calls for square legs with a turned recess near the top and a turned taper towards the feet.  Schwarz implies that the turned recess at the top is important because it gives you a place to grip the chair.  My first one didn’t have this.  For the second one I cut an octagonal recess.  In order to do this I made a series of parallel crosscuts with the bandsaw and then cracked out the waste.   This produces a rough square recessed area.  Then I smoothed it out with the router plane, chair2_sm and then I marked out the proper edges and used rasps to remove the corners to transform the square into an octagon. The result looks pretty good, but in the end, the only function it serves is that it gives a space for the leather that is wrapped across the backrest to go when the backrest tilts.  I never grab the chair by these “handholds” because the frame just twists.  If I do another chair I think I might just make a single shallow cutout on the inside of the back legs for the leather and skip the rest of them.

Unlike the recess in the middle of the leg, the taper to the feet is simple to do without a lathe. I started by marking the octagon on the bottom of the leg and choosing the length of the taper to be 10.5 inches. Hand planes quickly removed the corners of the legs up to the octagon’s edges, leaving the shape shown below.
legtaper1Next I measured from one triangular facet to the opposite facet to find the spot where the thickness was equal to the 1.75 inch thickness of my leg stock. This is the right spot to start tapering the legs to get a regular octagonal cross section. I marked this starting line and then tapered down to the octagon’s boundary marked on the foot, finally obtaining the completed tapered octagon:

legtaper2When I picked 10.5 inches I figured vaguely that the length of the taper on the square sides would be a bit smaller, perhaps by a factor like the square root of two. But working out the correct formula would have revealed that if I tapered the corners 10.5 inches I would only get a taper on the faces that went up about 4.25 inches. If I do this again I’ll run the taper up much higher. The length of the taper on the flat side is (ST)d / (S2T) where S is the thickness of the full leg, T is the desired thickness at the tapered end, and d is the length of the taper on the corner of the leg stock.

chair3_smSo how does this chair work? Alas, it is not as comfortable as the first chair. One observation I made after sitting in the first chair for a while was that the way I constructed the seat, which seemed initially like an unfortunate mistake, was actually a fortuitous move. The seat came out considerably looser than I had intended, and this made the seat more comfortable by giving it mobility. I was careful to model this second chair after than one in that respect.  (I marked a line eleven inches from each edge and folded the leather to that line.)  However, the stiffer leather makes the back of the chair less comfortable. With the softer leather, the bottom part of the back rest conforms to my lower back and seems to give a remarkably comfortable support to the lower back. With this stiffer leather, the bottom of the backrest is simply too close to the seat and it pokes me on the butt without conforming at all.  This isn’t so comfortable. After giving the chair more use I may try trimming off a few inches from the bottom of the seat.

chair5_smBut if I do that I’ll need to solve another problem first. Often when one leaves the chair the back ends up in a strange position. I have tried various schemes to stop this from happening. A perhaps related problem is the propensity of the bolts holding the back on to loosen themselves. I tried to solve these problems by inserting a lock nut under the wing nut, by using a wing nut and a thumbscrew, by inserting leather washers to increase friction, and by inserting Belleville spring washers to try to create tension that keeps everything together. None of these things worked—it always unscrews itself with use. If I remove leather from the bottom of the seat I’ll be taking more weight from the bottom and I’ll create an imbalance that will be even more troublesome. The only solution I can see is to add weights to the bottom of the seat supports, though that still doesn’t address the problem of the chair unscrewing itself.

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The backrest connected using a wingnut and a brass thumbscrew in an unsuccessful attempt to create a locknut combination that would keep the chair from unscrewing itself.

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2 thoughts on “Roorkhee Chair v. 2

  1. Adrian – I came across your blog after looking for examples of the roorkhees chair without turned legs. I love the two you have made, but i noticed that you do not seem satisfied with them. Would you make another and if so would you do anything different? Any advice as I get ready to make my first one? Thank you!

    • I might make another one. When you say I’m not satisfied don’t get the impression that the chairs are bad. The first one especially was quite comfortable. The thing that bugged me the most is that I prefer a chair that supports a more upright pose. These chairs are almost recliners. If that’s what you want that’s great. But it’s really not obvious how to change the chair to make it more upright.

      What would I do if making a third one? Well, one thing I would do is buy Schwarz’s book on campaign furniture and see what he has to say. I’m not that interested in the book overall, but it seems like his thinking on these evolved significantly as he kept making them. I noticed, for example, that he changed which reamer he recommended. I found reaming the holes at the right angle to be very difficult so using the drill press compatible reamer would help a lot.

      As I said above, I wouldn’t cut the “hand holds”, which look kind of interesting but are a pain with hand tools and don’t actually make a practical difference. I would do the octagonal taper, and would run it up even farther, as I said above. Consider making the legs overlong and testing the chair (before cutting your taper) and then cutting them down. The original chair is very low to the ground. I’m not even tall.

      I would probably weight the back frame of the chair to keep it from popping up. I actually have some brass I bought to use for this purpose to retrofit into the existing chair, but I haven’t put it in yet. I also haven’t gotten around to cutting leather off the bottom of the back to see if it makes char #2 as comfortable as chair #1. Perhaps the simple answer is to use softer leather. I don’t know enough about leather to understand the trade offs. The leather I used on chair #1 stretched far to much when used as arm rests.

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