Wednesday, March 25, 2009

Forging the BIG time

(Note to my regular readers: I spent from March 12 through 20 in Lexington Virginia at Smeltfest 09, hosted by Lee Sauder. Along with his long time collaborator, Skip Williams, the team also included Jesus Hernadez, Dick Sargent (Peter's Valley Craft School) plus Steve Mankowski and Sheldon Browder (Colonial Williamsberg). Expect field reports soon on this extremely illuminating week, concentrating on the Aristotle Furnace.)

Back to Wareham, and back to work!

After a long development process on the designs, I am now concentrating on the physical work for the Reade & Maxwell House project.

The first pieces under production are a pair of heavy support beams that re-enforce the first floor along the edge of an open concept stair well. Each is formed from a single length of 3 1/2 square tube, 3/16 thick - just over 100 inches long and weighing in at roughly 75 pounds.
Not to leave well enough alone, my design calls for each of these to be forged, with a shallow grove hammered down the centre line of each of the four sides. This is accomplished by using a heavy cross peen hammer as a die, striking it with a four pound hand sledge. ( I had started work using a top fuller with a more conventional 'straight peen' alignment. This put my left hand over the hot metal - which even in gloves gave off WAY too much heat as I worked along the section.)

The first trick is heating up such a long and massive piece of material. My homebuilt 'architectural' forge is designed with three burner ports along the upper surface. This forge also is framed so that one side can be removed, allowing large pieces to be inserted sideways. Placed so the propane jets wash down one side of the beam, one surface at a time, about 18 long, can be brought to a low orange. As seen in the image above, during heating the beam is supported on regular bricks to either side of the gas forge. (This keeps the weight off the more fragile fire brick insulating the forge.) It took about 5 - 8 minutes to bring each individual section up to forging temperature.
The second trick is physically manipulate the beam. Fortunately I invested in a heavy layout table last year - topped with a full sheet of 3/8 thick plate. The construction is rugged enough to allow the hammering to be done using the table top as a giant anvil. After each short length was contoured, I rotated the beam a quarter turn and levered it back up and into the forge to heat another segment.

This shows a finished section of the beam. A shallow groove has been hammered along the length of the originally flat surface. The metal has been depressed about 1/2 inch deep, and is slightly irregular in both depth and location. The end result is a far more organic contour to the entire beam. This is in keeping with the overall 'sea to sky' concept for the entire project.

More to Come!
 

February 15 - May 15, 2012 : Supported by a Crafts Projects - Creation and Development Grant

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