Monday, August 15, 2011

Cooking with Otis

Okay, not really. The pictures make it look like I'm marinating a stick of wood in beer and roasting it, but don't worry: things haven't come to that pass here at the Farm House. No, I was just working on the right cap piece from the east window casing.

As I mentioned last time, it's in nearly as bad a condition as were the cap pieces on the west casing; that is, it's nearly unrestorable: so sun-damaged and eroded that huge valleys and canyons have opened up, and so light and brittle that there can be no moisture nor lignin left. Unlike the other pieces, however, it hasn't become irretrievably warped and twisted, so we can save it with the old LiquidWood/WoodEpox one-two punch. Today I'll show you how punch number one went.

As you will recall, my usual method of applying LiquidWood is to brush it on the piece until no more is absorbed, drilling small holes as needed to aid penetration. This piece is so shot through with voids, however, both obvious and hidden, that I decided to try something more radical: submerging the entire piece in LiquidWood to maximize penetration and absorption. Another motivation was to provide sufficient mass of epoxy to ensure proper curing; you will recall the difficulty I had with getting the apron pieces to cure.

I made a trough of heavy-duty foil lined with plastic wrap, the kind that is translucent and slightly sticky on one side. The plastic was there to prevent leaks, and the foil was there to provide sufficient rigidity to conform closely to the profile of the piece.

Then, I poured in enough epoxy, after letting it sit in a container wherein its volume was taller than it was wide for 15 minutes to induce the curing reaction, to contact the complete extent of the piece (six ounces of mix):

I folded the trough walls over the top of the piece and sealed it up as tightly as I could. A half-hour later, I opened the trough and saw this:

The epoxy had been almost entirely absorbed into the piece and had begun to thicken, so I took the piece out of the trough and set it up on blocks to let it finish curing; I didn't want the excess epoxy to harden on the outside of the piece and distort its shape. 

Just to make this process clear, here's a detail to show just how thoroughly the epoxy was absorbed:

The wood was so devoid of moisture, and so porous from sun damage, that it absorbed the epoxy quite literally like a sponge, without benefit of drilled holes. Moreover, virtually none of it drained back out. 

The next morning, the epoxy was still just the slightest bit sticky, despite the extended induction period, large mass, and low-70s ambient temperature. So I put the piece in the dryer on low for an hour.

Now the piece was dry, sound, and as heavy as a fresh piece of wood. It was now zombie wood, really just a piece of fiber-filled plastic. But we're not done with it yet.

As you can see, there are still large voids that need to be filled with punch number two, WoodEpox. I've got a whole mess o' puttyin' comin' up.

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"Nice blog, but too many cats."


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