I’m not a great thread starter but thought one or two of you might be interested in a major project I completed a while back. Because this is a completed project I can start off with a photo of the finished article so anyone who is not interested in the “how” can just look at it and decide whether or not they like it and not have to plough through to the end.
A bit about the inspiration may be useful for starters. The idea for the table started germinating when my daughter was living in a small Edwardian cottage. At the time she had a small round pine dining table, bought second-hand for very little, with the top secured to the pedestal by a single large screw through the centre into the turned pedestal column – utilitarian but certainly not pretty. I thought it would be good to make something better. Space was restricted so a pedestal table seemed best, with no legs to get in the way. I got to thinking that a pedestal table is a bit like a tree, with a trunk, roots for stability and branches to support the top, so why not make it more literally tree like?
Although a lot of thought went into the design, it evolved quite a bit during the making, partly to solve unforeseen problems but also to make it a better resolved design. Much of the making was done on 5-day courses at West Dean College where I had the help of Bernard Allen, the tutor and very good friend, but also that of my fellow students who were always ready to lend a hand. Courses like these, where each student could make whatever they wanted were fantastic learning experiences and always hugely enjoyable but sadly, I fear, a thing of the past. Bernard has now retired and I can’t imagine anyone else wanting to take on the extra pre-course work of mentoring students, each with different project plans, let alone the stress of running six to eight separate projects in parallel.
Making the Tree Table took three years of very much part-time work.
My original plan was to make the legs from steam bent sycamore – an expensive lesson because every attempt at bending it failed; I didn’t know then that serious bending requires a ring porous wood like the English ash I eventually used.
The Pedestal
Steam bending, particularly when the component is relatively thick as here (18mm) is a lot less predictable than veneer laminating, not least because different amounts of bending are required across the thickness, leading to considerable stresses. When bent round a former, the inside of the bend will tend to compress the wood along the grain, while on the outside the forces will try to stretch the wood. While compression is perfectly possible and manifests itself in a way a little like the folded skin on the inside of a bent finger, the scope for stretching the wood on the outside of the curve is very limited indeed. This isn’t a problem with veneer lamination because each veneer behaves separately and they can slide against each other. To mitigate this problem with solid wood bending I used a steel strap bending jig to hold the work during the bending process. This aims to limit the external stretching and force more internal compression. Here is CAD image of the design I used. Apologies for the broken image, but the drawing and annotations give a better idea of how it works than I could give with words alone.
View attachment TT bending jig.jpg
And here is the actual (much longer) jig with wood wedged in it preparatory to actual bending.
And here the wedge is more clearly visible
Here is the wedging arrangement. Note that the strap wraps right round the wedging block and is bolted through the handle to cope with the considerable forces involved in a achieving the bend.
This photo. is of a practice run for the initial attempts – hence the sycamore blank rather than ash.
An early bending experiment with the West Dean student/tutor team - that’s Bernard Allen in the blue shirt giving directions. It was a bit like a bunch of headless chickens at first, with people getting in each other’s way in our efforts to get the bend done and clamped before the blank cooled too much, but things improved as we all got used to working systematically.
More to follow, hope you find it of interest. If anything isn't clear, please say so.
Jim
A bit about the inspiration may be useful for starters. The idea for the table started germinating when my daughter was living in a small Edwardian cottage. At the time she had a small round pine dining table, bought second-hand for very little, with the top secured to the pedestal by a single large screw through the centre into the turned pedestal column – utilitarian but certainly not pretty. I thought it would be good to make something better. Space was restricted so a pedestal table seemed best, with no legs to get in the way. I got to thinking that a pedestal table is a bit like a tree, with a trunk, roots for stability and branches to support the top, so why not make it more literally tree like?
Although a lot of thought went into the design, it evolved quite a bit during the making, partly to solve unforeseen problems but also to make it a better resolved design. Much of the making was done on 5-day courses at West Dean College where I had the help of Bernard Allen, the tutor and very good friend, but also that of my fellow students who were always ready to lend a hand. Courses like these, where each student could make whatever they wanted were fantastic learning experiences and always hugely enjoyable but sadly, I fear, a thing of the past. Bernard has now retired and I can’t imagine anyone else wanting to take on the extra pre-course work of mentoring students, each with different project plans, let alone the stress of running six to eight separate projects in parallel.
Making the Tree Table took three years of very much part-time work.
My original plan was to make the legs from steam bent sycamore – an expensive lesson because every attempt at bending it failed; I didn’t know then that serious bending requires a ring porous wood like the English ash I eventually used.
The Pedestal
Steam bending, particularly when the component is relatively thick as here (18mm) is a lot less predictable than veneer laminating, not least because different amounts of bending are required across the thickness, leading to considerable stresses. When bent round a former, the inside of the bend will tend to compress the wood along the grain, while on the outside the forces will try to stretch the wood. While compression is perfectly possible and manifests itself in a way a little like the folded skin on the inside of a bent finger, the scope for stretching the wood on the outside of the curve is very limited indeed. This isn’t a problem with veneer lamination because each veneer behaves separately and they can slide against each other. To mitigate this problem with solid wood bending I used a steel strap bending jig to hold the work during the bending process. This aims to limit the external stretching and force more internal compression. Here is CAD image of the design I used. Apologies for the broken image, but the drawing and annotations give a better idea of how it works than I could give with words alone.
View attachment TT bending jig.jpg
And here is the actual (much longer) jig with wood wedged in it preparatory to actual bending.
And here the wedge is more clearly visible
Here is the wedging arrangement. Note that the strap wraps right round the wedging block and is bolted through the handle to cope with the considerable forces involved in a achieving the bend.
This photo. is of a practice run for the initial attempts – hence the sycamore blank rather than ash.
An early bending experiment with the West Dean student/tutor team - that’s Bernard Allen in the blue shirt giving directions. It was a bit like a bunch of headless chickens at first, with people getting in each other’s way in our efforts to get the bend done and clamped before the blank cooled too much, but things improved as we all got used to working systematically.
More to follow, hope you find it of interest. If anything isn't clear, please say so.
Jim
glad you found the time to share, things like this give people inspiration and seeing what can be done gives a bit of confidence to get stuck in and try 
