Restoring Double Ended Duck Hunting Boat

[cshire]

Looking for the advice of the wooden boat experts here.

I have built a couple of stitch and glue plywood boats and have restored a plywood on frame drift boat (dory) so I have some decent experience, however my question relates to more traditional construction techniques for my newest project.

Last winter I picked up a traditional double ended duck hunting sneak boat. This boat was likely built in the ‘30’s or 40’s and was stored in a barn for at least 20 years. At some point the boat had been fiberglassed with what I assume was polyester resin on the hull exterior. This fiberglass was badly delaminated in many areas.

I am in the process of stripping the boat down and removing the glass cloth and remaining adhered resin as part of the restoration process. My goal is to restore the boat to a sound condition and get it back out on the Detroit River and Lake Erie as a working hunting boat.

The hull is constructed with a 14” wide (widest point) bottom plank/keel and then strip planked up to the sheer. Ribs were bent and set in on 6” centers for structural rigidity and both strips and bottom plank are nail (iron) fastened to these ribs.

The seam between the bottom plank/keel and the strip planked portion of the hull was traditionally caulked with cotton wicking and sealant. This joint was in poor condition and I am removing all caulking and sealing material. Gaps between first strip plank and bottom plank are up to ¼” (at the ends) now that this seam has been cleaned out. The first strip (garboard?) shows some rot damage on caulk face that will need to be addressed. The bottom plank is a single plank and has some warping and distortion at this time. The strip planked portion of hull shows a glue line between strips and these joints appears to be mostly sound. The nailed fastenings are in good shape but strips are showing discoloration where moisture has wicked through wood grain at nail holes.

So where do I go from here?

The bottom plank needs to be replaced. Possibilities include finding a suitably clear and straight pine or cedar plank to cut and fit in or using a plank cut from marine plywood. I am leaning toward the marine ply option as this will be easier to find and get cut into place, and ply should also remain more dimensionally stable and warp free if properly sealed. I would even consider fiberglassing both sides and the edges of the plank to ensure it’s stability and longevity.

I need to address the rot on first strip and how to seal joint between bottom plank and this strip. One option would be to fully replace the strip and stay with a traditionally caulked seam. An option I think may work would be to trim the first strip by about ¼” to get back to sound wood and then using a glued spline between bottom plank and strip planked section. I have read of this construction technique and seen some photos but don’t know many specifics on materials for spline and glues (epoxy or 5200?) or specifics of the techniques. Would this be a viable solution?

The rest of the hull work seems pretty straightforward – get a good sealant on all nailheads, replace sheer strip, prep and a couple of good coats of paint.

Is the glued spline option outlined above a good option? Where can I find a good write up of how to do this? Anything else that you guys think I need to address based on the photos and description I have given?

"Before" photos from last winter:

http://i4.photobucket.com/albums/y145/cshire/before1.jpg

http://i4.photobucket.com/albums/y145/cshire/sternendview-1.jpg

Current photos showing condition of hull:

http://i4.photobucket.com/albums/y145/cshire/Seam2.jpg

http://i4.photobucket.com/albums/y145/cshire/Stem.jpg

http://i4.photobucket.com/albums/y145/cshire/StripPlanking.jpg

http://i4.photobucket.com/albums/y145/cshire/Seam1.jpg

http://i4.photobucket.com/albums/y145/cshire/Overall2.jpg

http://i4.photobucket.com/albums/y145/cshire/Overall1.jpg

Interior Framing:

http://i4.photobucket.com/albums/y145/cshire/frontunderdeck.jpg

http://i4.photobucket.com/albums/y145/cshire/framing2-1.jpg


Thanks in advance for any advice.

[Bob Smalser]

Nice find. Well worth a good restoration.

From here I don't see the need to replace the bottom unless it is rotten. As the boat is easily moved, you might finish grinding off all that glass and sink her in the water for a week or two to see if that bottom plank will straighten out some, which I suspect it will. Your end result is usually better original than perfect, and I'd leave plywood a distant last resort.

Then it's just a matter of cutting out strip rot and replacing it with epoxy or resorcinol-glued splines, glued to the strips and not the bottom plank. Leave the caulking seam intact....spline it to close it to an 8th or less atop and touching below if you have to, but you'll definitely need a cotton-caulked seam there to avoid cracking, as the glued strips above and the solid bottom below mean all seasonal movement is taken up by that seam.

Then tightening loose and replacing deteriorated fasteners, sanding and fairing compound, red lead primer and paint. You've likely some steel nail sickness in those nailed strips, but there's not much you can do except keep it well-painted and replace strips when they get soft....dark iron stains alone aren't much of a concern.

[Peter Eikenberry]

A link you might be interested in. http://www.duckboats.net/duckboat.htm

[nedL]

I agree with what Bob recommends. Also. if the bottom plank is cupped so that it is concave on the outside (dryer outside than in) a simple cure may be to just let it sit on some wet rags / blankets on the lawn on a sunny day. That will add moisture to the exterior side while keeping the interior side dry. Its really amazing how a couple of hours of this treatment can change the shape of a piece of wood.
Nice looking boat & a fun project, well worth the time of a proper restoration.

[cshire]

Thanks for the advice guys. The bottom plank looked like a lost cause to me. I will definitely try to save the bottom plank if possible.

I've been working on this piecemeal all spring and summer, but now that September is only a month away I'm getting more motivated to get this ready for the season. I am on vacation all next week and plan to get the remaing glass and resin off and begin plank repairs as needed then on to the repairs.

Peter - I am a regular lurker (if there is such a thing) on the duckboats forum. Lou Tisch, who is a regular there posted a good write up on sneak boats and sneak boat hunting techniques last winter when I first picked up the boat. I just asked the question here based on the traditional construction vs. the stitch & glue that seems the more preferred method over there.

After this boat is complete I would like to build a tradtional barnegat box and a scull boat - so many boats, so little time.