kink in keel

[dannyb9]

my lovely, newly acquired 68 ds1 has a kink in the keel (hogged) about 18"behind the centerboard case. looks like it sat on a trailer with a lot of weight on a roller there. i am wondering if i can push it down into its original shape. i am thinking about a 2x4 crossbeam over the kink and under the side decks, using a scissors jack to force the keel back down into its original shape. anybody tried this? are there any remedies?
dan in port royal

[dannyb9]

my lovely, newly acquired 68 ds1 has a kink in the keel (hogged) about 18"behind the centerboard case. looks like it sat on a trailer with a lot of weight on a roller there. i am wondering if i can push it down into its original shape. i am thinking about a 2x4 crossbeam over the kink and under the side decks, using a scissors jack to force the keel back down into its original shape. anybody tried this? are there any remedies?
dan in port royal

ok i did it. the bottom keel actually has a couple of small cracks. i have the 2x4's, pads, etc in place and working. the keel line is now fair. i kept adding a little pressure at a time until i got it bent back into shape. if the dent is recalcritant i may consider an inner keel (keelson) and a skeg to hold the bottom shape. has this been tried? i imagine this is a common problem. now i will wait till my dg mast hinge arrives. until then i will admire the beauty of my newest family member.

[GreenLake]

I would be worried that your laminate is damaged/weak at that point, so adding a keelson would provide some strength. I would also be worried that your cracks allow further weakening of the laminate by letting water get in, so grinding and patching that area from the outside would also be advisable.

[seandwyer]

what is the keelson? I looked it up and saw some pictures - but in regards to the DS I just don't understand what it is or looks like or how it works in a DS. Maybe this is in a DS2 and that's why I can't comprehend?

I agree with Greenlake about cracking. the hull is flexible, but not that flexible and it would better to be safe about the stress points by grinding and patching.

[GreenLake]

Keelson would be the board (or stirnger) that rests on the keel. In the DS1 the mast is stepped on it. It ends forward of the CB trunk. If the area being the CB is dented, the idea was to add a similar central support there (epoxy saturated wood or hollow).

[dannyb9]

Keelson would be the board (or stirnger) that rests on the keel. In the DS1 the mast is stepped on it. It ends forward of the CB trunk. If the area being the CB is dented, the idea was to add a similar central support there (epoxy saturated wood or hollow).

yes, green lake and i are on the same page here. i am considering a stiff shaped stringer (keelson in this case because it rests on th e centerline from the cb case to the stern) to force the bottom into shape. i imagine it will be screwed and glued into place.

[GreenLake]

I would imagine that if you take a U channel, invert it, and tab it onto a well prepared floor (all paint etc. ground off) then you would not need any screws. Screws have the disadvantage that they disturb the existing laminate and that they are potential stress points.

You've used your special method to force the keel back into alignment. If it retains the new shape or if you can make it retain the old shape while the new fiberglass cures (I assume you'd use epoxy) then you don't need any temporary fasteners.

I would make the stringer hollow (with 3/4" holes in a few places to allow water to drain freely) and I would aim for a having it at least as tall as its wide, as the height is what gives it the strength.

For aesthetic reasons, matching it to the keelson that's in front of the CB would be an obvious choice. That one is about as wide as the CB. As you go aft, you could reduce the height of the stringer (letting it gradually disappear into the floor, so to speak). That's what I'd do in my boat, because there's a drain plug in the bottom center of the transom.

It should be possible to pre-fabricate a bit of channel, then grind the edges for a tight fit, fair the corner where the edges meet the floor into a gentle curve by adding fairing compound and finally glass it onto the floor. With that approach, you could use a few dabs of 5 minute epoxy to "fix" the stringer in place.

If you build the stringer in place you need some kind of form, and unless you make a hollow form out of epoxy saturated cardboard, you're going to end up with a filled stringer - that always has the disadvantage of providing a secret place where hidden water can accumulate unseen.

I'm probably just writing down all the things you have thought of already

[K.C. Walker]

I think that you are right about it being a common problem. I think it's interesting how the hull seems to take a set from being on a trailer. I'm not sure that pushing it back into shape would be enough to keep it from springing back. However, it seems like pushing it into shape and waiting a bit to find out how much pressure it would take to keep it straight would be a good idea.

If it does not take a lot of pressure to keep it in shape, it seems to me the easiest solution would be to use a wood stringer and epoxy it in to place using the same method that you are using to press your 2 x 4s. If you were to totally enclosed it with epoxy and put some glass over the top I think you would have little chance of problems.

I had the same hog in my boat and I know others who had similar hogging where the trailer bunks contacted the hull. My boat already had a stringer put in that location to try to solve the problem. However, I think they actually cemented the problem into place. Once I removed that stringer and the other stringers I was able to get most of the hog out (I wish I thought of trying to push it all out). I reinforced mine with half-inch structural foam covering the bilge area, an extreme measure for sure.

KC