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bob winter
02-12-2009, 07:49 AM
Work on the boat has kind of ground to a halt, mainly because it is damned cold in the garage. However, I am anxious to get on with things since I would really like to get the boat in the water while I am still alive.

There is a crack in the starboard gar strake just ahead of the centre of the boat. It is not evident from the outside of the boat and it appears to me that the boat sustained some sort of blow that flexed the strake in and caused the crack. On the inside of the boat, the crack is maybe 1/8 wide at the middle closing off to virtually nothing where the strake is resting on the frames.

I think I can get epoxy injected into the crack and then force it closed while it cures, assuming I can get the temp. in the garage high enough. I assume the temp. of the wood is the important factor, not the overall garage. I am using something called Cold Cure that I picked up at Lee Valley. My question is whether or not I should depend on the epoxy by itself to hold things together or if I should add some sort of mechanical backup in the form of a piece of plywood or whatever attached to the inside of the planking. If I do need backup should I epoxy it to the planking or should I just screw it in place with bedding compound.

Any insights will be appreciated.

I took this picture but the quality is far from good. The crack is about 2/3 of way up the strake.

http://i433.photobucket.com/albums/qq58/wintek1/100_0531.jpg

Gary E
02-12-2009, 09:34 AM
I think I can get epoxy injected into the crack and then force it closed while it cures, assuming I can get the temp. in the garage high enough. I assume the temp. of the wood is the important factor, not the overall garage. I am using something called Cold Cure that I picked up at Lee Valley.
Your in Canada... when does it warm up?... July? August?? and that's not in your garage, so maybe Sept??

Cracks happen, and they close up when the wood returns to normal when the boat is back in the water.
Do NOTHING to the crack inside the boat. IF...again IF the crack opens when viewed from the outside, put some soft, never will harden compound in there to stop the water untill the plank swells and closes up the crack.

One other thing... make sure you have a BIG pump, it can take a week to swell up.

willmarsh3
02-12-2009, 10:23 AM
Some questions. Is the boat carvel planked? Is it currently upside down? Will it be dry sailed or left in the water? I think I'd avoid epoxy since as the wood swelled up it would want to fill the crack. With epoxy present it won't be allowed to swell up that way. Instead it will swell up elsewhere and cause more problems. I'm curious what others with more experience here say.

bob winter
02-12-2009, 10:52 AM
The boat is lapstrake and it is presently right side up. The plan is to finish the interior and then flip it over and do the exterior. The crack is the result of some sort of trauma to the hull, likely the same fall that caused the screws holding the planking to the transom to fracture. As I said above, the crack is not visible from the exterior so I think the planking is pushed in a bit.

This boat has been out of the water for years and it will leak like crazy until it takes up, if it ever does. I plan to take it to the cottage eventually and leave it in the water, with a proper cover to keep the rain out, for most of the cottage season.

I am attaching a shot of the transom after reinstallation:

http://i433.photobucket.com/albums/qq58/wintek1/boat/100_0485-1.jpg

Oops, that is before the reinstallation was completed, in place but the fastners yet to come.

Gary E
02-12-2009, 10:58 AM
I assumed a much larger boat, so the only change I'd make to my sugestion is...
skip the bilge pump, use a sponge.

Bob Smalser
02-12-2009, 11:37 AM
.... The crack is the result of some sort of trauma to the hull, likely the same fall that caused the screws holding the planking to the transom to fracture.....



Maybe. Maybe not. I don't see any cracking across the grain that would definitely indicate a collision. If the crack is in the widest area of the widest plank, then shrinkage as a result of too much drying is a more likely culprit. Seasonal movement has been fighting those tight rivets nearby for decades, and when the wood got dry enough, something had to give, and it gave at its weakest area neatly along a natural growth ring or ray.

http://i433.photobucket.com/albums/qq58/wintek1/100_0531.jpg

That means I wouldn't risk anything hard in there, or it will act as a wedge and split the plank completely when the wood swells. Finish your restoration and see what it does after the boat takes up. If you feel you must do something about it, use an ashesive sealant that'll remain soft like 3M 5200 or Vulkem 116 poly caulk.

bob winter
02-13-2009, 06:51 AM
Thanks for the advice. I will leave it alone for the moment and see what happens when the boat is in the water. Hopefully, all I will need is a spounge as opposed to a pump.

Eric Hvalsoe
02-13-2009, 11:00 AM
I noticed some cracks in a hull recently in the shop. For me doing nothing was unsatisfactory, although the do nothing option may be fine in a number of cases. I had about a two foot long grain line split through the middle of the garboard. It had not opened up, but the two surfaces had sprung apart vertically a little bit. The boat was upside down. I braced inside to get the surfaces even, then ran a laminate trimmer with half inch channel bit along the outside of the split with a guide strip attached to the hull. I went about 1/4" deep (3/8) plank, sure to run just beyond the ends of the split. The split was straight and it was situated such that there was room to run this small laminate trimmer. I epoxied in a bit of plank stock and faired off. The exterior of the hull is painted.

There were a couple other short splits where the router trick was not feasible or unwarrented. Here I slightly enlarged the exterior gap of the split by dragging my dental tool through to get bit of a V groove, then filled with epoxy.

Yeadon
02-13-2009, 11:23 AM
When I was riveting in frames on my lapstrake peapod, a friend of mine dropped a pretty heavy bucking iron about four feet into the boat and onto the starboard garboard. Sounded like a gunshot as the end of the iron cracked the plank up near the hood end at the stem. The crack was probably 15 inches long and you could see a bit of daylight through it.

After I got done throwing up ... we drilled each end of the crack to stop it from spreading, then I did what Eric described above ... I opened up the crack a bit with an awl ... warmed the plank with a pair of heat lamps ... then saturated the crack with warmed epoxy. Once it was saturated, I thickened up the epoxy with wood flour, and kept on pouring until the crack was full. I believe after a while I sealed up the outside with duct tape ... or some type of tape, and that allowed the crack to fully fill with epoxy. Later, I faired it out and went on my merry way.

Afterwards, I halfway considered naming my boat "Dragon Fill," short for "dragged and filled" with epoxy.