Protrusion on topsides

[Homer]

I would welcome advice from this august forum on a repair with which I have no experience. A protrusion (about 70 sq in) developed on Yankee's topsides a couple of feet down from the rail sometime after slamming into a piling during Hurricane Ike. I assume it is due to impact, but cannot be certain. I did not notice it until months later. The exterior skin is not fractured and there is no internal damage. The topsides are balsa cored. I have not drilled into the thing (pencil mark defines perimeter in the photo). Tapping reveals precious little difference in sound, not at all like delamination in the deck due to water infiltration. I know that sound. How shall I proceed to investigate and repair? I would not think that the prominently convex skin can be forced back down and reglued, but I could also be wrong about this. Would it be proper to simply cut out the protruding skin, taper the sound edges, and build up a typical patch with epoxy and cloth and then fair it out? Of course, patching would occur only after any invisible damage was repaired. This is not on my immediate "to do" list, but the thing is puzzling. Has anyone seen this sort of thing before? Thanks.

[One Way David]

I'm not an expert by any means, but that looks like a previous repair that was poorly faired and finished. If you say there is no evidence of damage to the inside I don't see how blunt force could cause that. If it wer twisting or racking I would ecpect it to look more linear, again wwith evidence of damage elsewhere. I hope some of the more knowlegable folks chime in. Dave.

[Rachel]

Is it just me, or is the image not able to be any larger than postage-stamp sized? I see it says something like "viewed 185 times," but it doesn't do anything when I click on it, and when I do a "view image" it opens up in a new window/tab but is still tiny.

I don't know that I would have anything to add to the discussion, but still -- I wonder if others are also only seeing it small; maybe that is a reason for the low response rate?

Rachel

[Homer]

I just attempted to take better photos. No luck. I put a larger original and a seriously darkened/contrasted one here: http://www.utdallas.edu/~mont/Yankee/
This bump showed up following Hurricane Ike. Yankee was slammed around a lot although the surface of the bump shows no particular abrasion.
Any advice about how to proceed would be welcomed.

[bcooke]

The exterior skin is not fractured and there is no internal damage.

How do you know that there is no internal damage? Obviously there is something going on. Either it is a manufacturing defect - in which case I think would would have noticed it before - or it is damaged. If you can't determine what it is with a tap test I would drill a test hole or two.

I would not think that the prominently convex skin can be forced back down and reglued, but I could also be wrong about this.

No, you are not wrong.

You may be setting yourself up for some serious time consuming cosmetic work if you cut into this thing. Leaving it alone and making sure it isn't getting worse might be the easiest solution.

[Rachel]

Thanks, Homer. Both of the photos at your link were larger than the one I could see in your first post.

I realize you say there is no damage on the inside, but could you post a photo of what is on the inside at that location? Someone here might see or think of something from that.

I wonder if it could be a previous repair that was faired with something like Bondo, that can soak up water. Not sure why it would "morph" just after a hurricane, but could that have been the last straw, and it finally soaked up enough water to bulge? Sounds far-fetched, but then I don't see any "near fetched" answer.

Rachel

[Homer]

Thanks for the thoughts. I will get back over to the boat the end of the week to take an interior photo. A repair of some sort will be necessary before painting the topsides. I expect drilling a small hole to investigate is the way to go - perhaps from the inside. I cannot imagine any cheap-o repair was ever attempted. Yankee was maintained by Hinckley for her first 28 years and the owner before me was intensely top flight with everything he did.

[Homer]

Yep, found the problem the second time around thanks to your suggestions for a closer look. I had missed the bump on the inside just aft (to the left) of the internal drain. Tapping defines the perimeter of what is visible in the photo - same size as the external bump. I guess I will enter from this side to investigate and repair. Thanks.

Photo: http://www.utdallas.edu/~mont/Yankee/Inside%20hull.jpg