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Re: Cedar Strip/epoxy Mainenance
By:Paul G. Jacobson
Date: 9/18/2000, 5:44 pm
In Response To: Cedar Strip/epoxy Mainenance (Barry Santana)

: About 9 years ago I completed a cedar strip canoe. It was in Alaska and the
: only way to get it to my cabin was to fly it in on the floats of a float
: plane. After arriving at the lake (about 2 hours out of Anchorage) it
: looked fine. I launched it and everything seemed fine. The next day I
: noticed the appearance of "distress marks" on the hull at areas
: of steepest curvature. It appeared as if the fabric popped out of the
: resin. It wasn't too bad and it didn't really bother me too much. The
: epoxy was the West System and it was varnished with spar varnish. I am
: wondering if it was stress from the flight or thermal stress.

: I moved it out of state on top of a car about one year ago. It was covered
: with bubble wrap. Temperatures were pretty high in southern B.C. where it
: ended up. It now has more of this distress, even on the less curved parts
: of the hull. Does anybody have an explanation? Is there a preferred way to
: repair? I was going to strip the varnish, add more resin, sand and
: refinish. Is there anything that I need to know about prepping the surface
: of the old fiberglass? Any help or comments greatly appreciated. Thanks

: Barry Santana

sounds like thermal rather than impact stress. It could be from moisture in the wood condensing during the cold flight, and then evaporating from the heat of direct sunlight.

If it doesn't actually leak, and the boat is still holding together, then you probably don't have to do any repairs at all -- at least for a while. I suspect the problem is on the bottom of the resin, next to the wood, so putting additional resin on top of the existing surface would be a waste of time and money.

To maintain things you should lightly sand and varnish. This is just to prevent further damage from UV light.

If the epoxy and glass layer ever cracks enough to start leaking, or shows signs of separation from the underlying wood, you can make a temporary patch with duct tape. Hopefully that should last until you get the time to do a major repair job.

When you do repair this, you must sand through all layers of the affected glass and resin. Go all the way to the underlying wood, and start again.

From your description it sounds like you may have two to four large areas to patch. Feather the edges of the good glass that remains on the boat for at least 2 inches on all sides from the exposed wood area. Trim a piece of calss cloth that is an inch or two larger than the feathered area.

A sealing coat is not necessary as there should still be epoxy in the wood. Paint on a coat of resin, and while it is wet, lay on the pretimmed patch of glass cloth. Go over this with a squeegee or a brush loaded with more resin to wet out the glass, and let it rest until the resin has set. Then sand down the overlapping glass cloth, using your fairing board as necessary to get a smooth finish. Lightly sand the center of the patch, just to knock off any high spots from drips or runs, and apply two filler coats of resin to fill the weave of the patch. Then sand the whole canoe lightly and varnish the whole thing. The patched areas will probably be unnoticeable.

You might as well wait until the boat gets REALLY banged up. Evne if that takes a few more years (or decades). You can repair all the other damage that might have happened over the years at the same time. When you are done the boat will probably look like new.

Hope this helps

Paul G. Jacobson.

Messages In This Thread

Cedar Strip/epoxy Mainenance
Barry Santana -- 9/18/2000, 12:35 am
Re: Cedar Strip/epoxy Mainenance
Paul G. Jacobson -- 9/18/2000, 5:44 pm
Re: Cedar Strip/epoxy Mainenance
Barry Santana -- 9/19/2000, 12:56 am