Tuesday, July 19, 2011

'Crab' - Designing to Forged Elements :

Regular readers know that CanIRON 8 is coming up in a week (!) I will have to go straight from being team leader at CanIRON - to teaching at the Goderich Celtic College the next morning. After a week in Goderich, I have all of three days to prepare for my other major show, Summerfolk in Owen Sound. For those reasons, postings may be kind of thin over the next four weeks!

Image by 'Captain Hook' - taken from his collection :
Shells encountered while sailing on a sailing catamaran off of Marco Island, FL.

I have always been drawn to the water, and since I was a kid, interested in bugs and crustaceans. Many years back, I spent a magical week in the Florida keys, and one of my treasured beach combing finds was a large spine from a horse shoe crab.

Now, those watching my work know that a recent series of larger sculptural pieces is the 'Hallucigenia' series. These are pieces based on the fantastic creatures from the Burgess Shale. (see the complete 'Songs of Distant Oceans' series pieces)

For CanIRON 8, a special theme for Gallery is “Joined by Joints”. This defined as " works employing mechanical joins which are not welded, brazed or soldered" - the use mortise & tenon, rivets and other non-welded joints.
Now, outside of rivets, I don't actually very often use those mechanical joining methods. The intent of the theme category was to get us all to try some new techniques, and I certainly wanted to get one piece ready to display. (That and I have not done too much new artistic work over the last year, and did want SOMETHING to exhibit to show I'm some kind of artisan blacksmith!)

This is what I came up with.

I decided, especially since there are a lot of better technical smiths out there than I am, to work inside my strength, which is in design. So the piece is based on the concept of a wedged joint, rather than the mere functional aspect of a wedged joint.
I also wanted to work inside a principle common to the best of contemporary artistic blacksmithing work, that being heavily sculpted shapes. I worked with generally heavier starting metal stocks than is normal for me, then each piece is so aggressively forged that the original starting stock is completely re-profiled. This also results in a work of considerable size (the finished work will be over three feet long.)

The rough form of the piece is inspired by that simple horseshoe crab, with a heavy segmented body shell that ends in a long spine. From there, the bizarre world of the Burgess Shale takes over, suggesting a creature that never survived into our modern age.

As you can see in the original layout drawing, there is one element that forms the 'hoop' which the wedges tighten against. This portrudes from the shell, then tapers into two long tentacles underneath. There are three wedge elements, a heavier central element ending in forked spirals, plus two curved 'antenna' pieces.

The two shell pieces will be folded, riveted along that line, then folded back, creating a pair of ridge lines on each. After this the pieces will be hot dished for contour. When complete, these will be riveted to each other, and the long spine piece riveted to the lower shell.
If the cutting and fitting is done carefully, the hoop holds the three wedge elements tightly as they are tapped into place.

Although I did have a rough idea were I was going, I started by forging the main elements individually. Once more or less completed, I then combined them over a full scale outline drawing of my proposed shell pieces.

You can see here how the elements have been translated from the original layout into forged metal. At this point I have not bent the central element into its final hoop shape. The last step on that piece will be contouring the two ends into fluid curves. Working with coloured markers, I am able to determine the rough shapes for the shell pieces, which will be torch cut from 1/8 thick steel plate.

Working with the individual pieces over a full scale drawing lets me generate a final paper template. These will be used as cutting layouts for the steel plate. You can see one change made in process here. I decided to take the top end of the spine (forged from 1/4 x 3 inch flat) and further forge that end. I will cut the bar back along the chalk line, then split and draw out the two sides into a kind of swimming fin on a tentacle.

I had originally intended on following this up with a short photo essay on what happened as I fitted the two shell pieces to the other elements - and what changes this imposed on the overall design. With CanIRON 8 looming, I just did not have time to record the work as I rushed to complete this major piece in time for exhibit:

The total length is roughly four feet! (And I know that is a horrible image!)

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

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