It's hogged

[MGC]

I'm working on a canoe that is hogged. It looks like the classic saw horse set.
Has anyone ever successfully and permanently corrected a hogged hull? I saw those pictures of a Huron bathing in an aluminum canoe... It looks like that one was corrected a bit....but what happens to it when it gets good and wet?
I'm guessing the one I have has about a half inch dip from the end of one stem to the other. The lines are pretty good...except she's hogged!
All suggestions (except gasoline and matches, thank you Andre) will be given the deepest possible consideration.

 

[Dan Lindberg]

I was storing a Thompson some years back that my wife's cousin managed to hog very nicely. He stored it out under the eaves with a small sail boat sitting on it.

Anyway, I rigged up a 2x on the floor and another held/supported by the rails, that short sticks were wedged in to push the bottom down.
I let it sit like this for several years, soaking it every so often.
When the canoe was parted with, it wasn't hogged as much, but still not flat or convex.

Dan

 

[MGC]

Anyway, I rigged up a 2x on the floor and another held/supported by the rails, that short sticks were wedged in to push the bottom down.
I let it sit like this for several years, soaking it every so often.
When the canoe was parted with, it wasn't hogged as much, but still not flat or convex.Dan

 

[MGC]

I was thinking about something similar, wetting the hull regularly until as soaked as possible, pressure from the inside of the rails to the bottom but flipping it bottom side up and then covering with plastic before steaming from inside...I'd have to make a crapload of steam. I figured I'd put a 2x on the outside between the stems to limit how far I pushed it.
This is what I'm thinking about when I should be sleeping? Good grief.
You gave me hope.

 

[davelanthier]

I have successfully removed the hogging on many canvased canoes using 3 pieces of 2"x 2" lumber and an electric steam kettle. Place one piece inside the hull lengthwise on the hog. Place the next piece across the beam under the inwales like a thwart. The 3rd piece or upright is forced between the other two pieces. Wooden wedges can also be used to increase this force as you progress. Turn the canoe upside down on saw horses. If the canoe is not canvased I would place some poly on the hull exterior. Mount the steam kettle on what ever you have so that it is inside the canoe and about 3" below the center of the hog. Steam away. Some blankets on top of the hull will help to hold in the heat. After a kettle full of steam has been applied let the canoe rest for at least a week . Leave the 3 lumber pieces in during this time or longer if you wish.

 

[MGC]

I have successfully removed the hogging on many canvased canoes using 3 pieces of 2"x 2" lumber and an electric steam kettle. Place one piece inside the hull lengthwise on the hog. Place the next piece across the beam under the inwales like a thwart. The 3rd piece or upright is forced between the other two pieces. Wooden wedges can also be used to increase this force as you progress. Turn the canoe upside down on saw horses. If the canoe is not canvased I would place some poly on the hull exterior. Mount the steam kettle on what ever you have so that it is inside the canoe and about 3" below the center of the hog. Steam away. Some blankets on top of the hull will help to hold in the heat. After a kettle full of steam has been applied let the canoe rest for at least a week . Leave the 3 lumber pieces in during this time or longer if you wish.

Brilliant! Hearing that my crackpot idea has been fleshed out and is a proven process is all the encouragement I need.
How long do you steam it? Good advice to let it sit for at least a week.
Mike

 

[MGC]

I've been struck by an epiphany. It's amazing what weed whacking a half mile of trail in 90 degree heat can coax out of your brain.
Here's the plan...a spin on my original thought and a bit of a departure from the way that Dave has done this...
The canoe was built with a keel so it has holes drilled through every other rib where the keel screws were fitted.
What I will do is build a bit of a strong back to mount on the outside of the hull between the stems. I will screw into it from inside the canoe and use the pressure from the screws (more likely small lag screws with hex heads so that I can pull apply lot's of force) to pull the hog up to the strongback. I'll use plywood inside the canoe to spread the load across the ribs and so that I don't pull the screws through the ribs as I crank down to pull the hog up to the strong back. Using this approach I can make sure that I evenly push the hog out and I can avoid applying pressure on the underside of the rails that might distort the tumblehome.
I'll cover the entire contraption with some plastic (and blankets as suggested by Dave) and then run my steamer inside the hull as it sits on saw horses. After it's steamed and the hog is pulled to the strongback I'll let it sit for a week or so. I'll take some before and after pictures in case it actually works.
If I remove the screws and see that it hasn't completely been restored I can space the strongback up and repeat the process, this time pulling it a bit farther.

 

[Dan Miller]

Sounds a lot like the way I removed hog from a Thompson Hiawatha some years ago. The short term results were very good - no idea how it fared in the long run.

 

[davelanthier]

MGC, one kettle of steam. Your over thinking this. I wouldn't use an exterior strong back as you want too reverse and extend the hog somewhat while steaming with tension. There will be some reverse come back after the pressure is later released. If your old keel is also deformed replace it with a new one which will help to improve and maintain your desired hull shape.

 

[MGC]

Dave, yes...I do think I need to push it out past where it looks right and expect some springback when I let it go... I'm just concerned about moving it too far but I suppose that is unlikely. Absolutely agree about the old keel...I'm making a new one along with new outside stems....Dan's hanger is the salient point....what will it look like 5 years from now (assuming I succeed)...
Mike

 

[davelanthier]

Your over thinking it Mike. If for some unknown reason the hog comes back in the distant future, which it unlikely if the canoe is stored properly, that’s ok. What other choice do you have right now ? For peace of mind you can always re-instal the tension pieces when the canoe is stored. Remember, you or someone else can easily re-steam it 5 years or 25 years from now, even with the canvas on, if the need arises.

 

[MGC]

I'm not big on wasting a good crackpot idea. My friends have often commented on my fertile mind ("Mike you are full of s**t") so over-thinking it or not, we are off to the races.
I had a few nice straight pieces of 2x4 around so I made a quasi "strong back" and screwed it to the canoe from stem to stem. I used the keel holes to run screws from inside the canoe to the 2x4 contraption.

You can see how badly hogged the boat is in this shot taken before I pulled the screws tight.

I filled the canoe with wet towels and let it sit overnight before flipping it and laying wet towels on the outside.

Tonight I plan to cover it with plastic and start up the steamer under it. I'll allow it to sit for at least a week before I loosen the screws and see how it ended. If it did not move enough I'll do it again but pull the hog out more.

 

[Andre Cloutier]

Mike please take note that I’ve evolved beyond the childish response of matches and gasoline. Bad for the environment and far too time consuming

 

[Howie]

Well... I was going to make a joke about getting rid of the hog by using an aluminum 'I' beam for the keel.
Then I started to think about plywood 'I' beams used nowadays for joists in homes and how they're more rigid than solid wood. At least, I think they are, right? Anyway, you could mill up 8 15' long x 1/8" strips of oak or ash - taking care to cut them with the grain - then gluing them together to form a 1" by 1". Yeah, I know... tough to glue up. But mightn't it be less flexible than a non-laminated piece?

 

[Fitz]

I tried the 2x4 strongback idea once on a big Honking 20 foot Huron. I bolted it down good and periodically poured hot water into the hull. I left it for a month. After I took the strongback off, it slowly creeped into a hog again.

This canoe probably should have been built with a keel and a keelson and that would have helped. You will likely have better luck.

Cheers,

Fitz.

 

[MGC]

Andre has stepped up his game! Reminds me of an upsized version of the torch I used on my first pair of nice racing ski's...the lignastone edges were a bit charred after I applied the first coats of Baltimore Oriole pine tar. I got pretty good with the torch after that first event.
Fitz, my expectations are aligned to your experience....I don't think there will be lasting salvation. We'll see.
The canoe did have a keel and outside stems that I will eventually replace. The keel might help a bit.
Howie....I ain't gonna be making any carbon fibre/graphite composite beams for this bugger. If I can get a canvas on it it's done.

 

[Dan Lindberg]

Mike,
I suspect the thing missing in your plan is time.
I suspect that after a good soak multiple times with water, and the with the hull physically held in an "over bend"
it needs to sit at least 6 months and maybe more to have any long term success.
Dan

 

[MGC]

Time is not a problem. I plan to let it sit most of the winter while I do odds and ends and work on another boat. It will get varnished sometime this winter but it won't get canvased until next year...after the snow is gone so probably no sooner than May.
Right now it's drying...I steamed it for quite a while today. I kept the wet towels in place on the outside and covered the whole thing with plastic and a blanket. It held heat/steam surprisingly well.
Hopefully I can get the towels dried and back in place before my wife figures out what I've been up to.

 

[davelanthier]

Mike, I know my method works. Sceptical about your method plus it may leave your ribs with water marks. Good luck.

 

[MGC]

Mike, I know my method works. Sceptical about your method plus it may leave your ribs with water marks. Good luck.

I don't know if what I'm doing will work but except for how we applied the force to remove the hog they are nearly identical....I'm pulling towards a known location, you are pushing...both methods exert a force from inside the hull, mine using existing screw holes and yours using braces from the inside rails. Your method provides more opportunity to push well outside of the hulls lines, mine is a bit more controlled. I was worried about rounding the hull by pushing too hard from the rails...I'm not keen on the way Peternut hulls lose shape and end up with rounded bottoms. I tried to contain the pressure to the areas were it was the most hogged. My hull was close to correct in the middle and towards the stems but saggy near the seats.
So far so good. It's dry to the touch and since I had the hull super clean before I tried this, no staining or water marks. It's ready for sanding once it's sat for a while. The towels are in the drier and the blankets are back where I found them. I might get away with this.