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Bending a new stem

The past few weeks have not been great in terms of boat restoration. Every project has its highs and lows, and last weekend saw the project in a state of despair. Lighting a match under the boat seemed like a viable option.

Keel in the jigBefore I get into details, I purchased some quarter-sawn white oak for the keel, stem and ribs. With my Dad’s help we cut the 11′ section for the keel, and made up two blanks for the stem. The keel worked out well, and after drilling out the holes for the ribs, it is ready for installation. Here’s a picture of the keel with my drilling jig.

The despair part of the project came when attempting to bend the stem. The stem is 5′ long and  1.75″ x 1.75″, that’s a lot of wood to bend. I put together a steam box of PVC pipe, wrapped it in blankets to keep it warm, and with this ugly rig managed to keep the temperature at around 95C at the end. The stem was cooked for two hours, and we then attempted to bend it over the form. Unfortunately both blanks broke during the attempt.

Steam box

In hindsight, the mistake I made was to attempt to bend a thick piece of kiln-dried wood. The kiln-drying process damages the cell structure of the wood, which is fine for almost all applications except for steam bending. It’s an expensive lesson to learn, but learn it I have.

IMG_20140217_115813What now? Finding air dried or green quarter sawn white oak is very difficult. Instead with the advice of my local wood supplier I’ve decided to laminate the stem instead, with 1/4″ pieces. They are cut, just need a good sanding and epoxying. I may steam the pieces just to make them a bit more flexible, but I can almost bend them over the form without steaming, so hopefully this will work better. To the left is a picture of the form with the old rotten stem over it. The form has large holes drilled into it for clamping purposes, which were drilled after the picture was taken.

Once the stem is laminated it needs a lot of shaping (my favourite activity, turning wood into shaving) and the installation of both stem and keel. And the move onto the ribs. I’ve decided to replace all the ribs, as there are only ten or so of the fifty that are not in rough shape, so while I’m at it I may as well replace them all.

 

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