Gragg

Steam Bending Demo

About a month ago, a mere three weeks before I was set to leave for Woodworking in America, I received a note from Jay Christian, Program Chair for the Washington Woodworker’s Guild, reminding me of my presentation to them on the evening of October 15.  Immediately I checked my calendar and smacked my forehead.  I enjoy presenting to the Guild and have done so close to a dozen times over the decades, but this one presented some scheduling problems.

The evening for my scheduled presentation coincided with my plans for packing so that I could depart for Cincinnati the next morning.  Given the late date of the reminder, I felt there was no way I could ask the Guild to reschedule and so I simply proceeded with the presentation as scheduled.

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My topic for the evening was the steam bending of parts for the construction of the Gragg elastic chair, one of the favorite research projects from my nearly three decade long career at the Smithsonian Museum Conservation Institute.  I’d shown the chair at a previous meeting’s “Show and Tell”, and they invited me back to show exactly how I was doing it.  I will be blogging extensively about the two Gragg chairs I am building over the winter.

Much to my delight my protégé Daniela was able to arrange for her husband to watch little Pedro so she could attend.  That was exceedingly helpful as she and I had worked out a choreography for the necessarily rapid forming of these complex parts.

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A demo of this type requires a large inventory of materiel, tools, and devices, including my petite bodger’s shaving horse built from a recycled half log that used to be a door header from a log barn and a variety of scraps from the wood pile.

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Another favorite fixture is my shaving beam that can be clamped to a work surface.  The beam has a mondo cam clamp at one end and a tiny wood screw at the other, so I have a lot of flexibility to either pull or push a tool against the work piece.  It is a genuine favorite accessory, and is used extensively when preparing the stock for steam bending.

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I covered a wide range of topics including harvesting, and demonstrating splitting, and riving, shaving, and planing the oak stock.

 

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The tight serpentine form of the major side element for the chair — it begins at the crest rail of the back and ends as the front foot — requires bending straps to help everything bend without breaking.

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Once the piece has cooked properly, in this case for about 20 minutes once the steam chamber gets to proper temperature (about 180 degrees or a bit more) out it comes.  It is as hot as you would expect, and often I use welding gloves.

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To make things move more quickly I marked out the locations for the straps on either side of the element, and we quickly clamp them in place with Vice Grips.  We only have about 60 seconds to get everything done.  We almost hear the clock ticking in our brains as we get going.

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At thirty seconds I’d better be wrapping up the first curve, setting up for the opposing second curve.  Haste is not helpful if it is jerky.  I have to work steadily but quickly.

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By the 45 second mark I need to be working on the second of the serpentine bends.

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The last step is to tighten the wood screws that inflict the return sweep onto the bottom of the front leg at the 60 second mark.

Done!  This bend went perfectly.

While I had hoped for a 9PM conclusion, between my longwindedness and the audience’s enthusiasm it was more like 10.30 before we got all wrapped up and on the road, and 2.30 Wednesday morning before pulling up at the cabin.  The next morning we unloaded, reloaded, and spent nine hours driving through the rain to Cincinnati.

 

Photos courtesy of Barry Ingram and Joel Jacobson