Crack front of centerboard, nearly through hull

[BaltimoreChess]

I’m fixing some cracks around the front of the center board, on the hall. I read through a bunch of the other forum notes. My plan is to use fiberglass mesh, and vinyl resin to build up and fill in the gaps where I ground down. If you zoom in on the spot towards the front, you can that it looks like I am almost through the resin entirely. You folks think I should go all the way down to the mesh, or should I stop where I am at and do the glass and resin work? I’m open to any suggestions about how to build up around the plate screws as well.

Bonus question is about the antifouling paint. We are going to repaint bottom of the boat antifouling and the free board as well later the anti-paint seems to be pretty solid on the hull. My plan presently is to do a light sanding and then repaint with antifouling. Or, maybe I need to sand, prime, antifoul?

Hope folks find the surgical gown on the boat as amusing as I do.

Geoff
Baltimore, MD

[BaltimoreChess]

Providing an update! I kept grinding away at the cracks near centerboard trunk on bottom of hull. I found that most of them went all the way through hull. To resolve I used glass cloth with west system 105 epoxy/502 hardener.

For front of centerboard trunk area - small spider cracks were ground out this included going down into slot. I put multiple layers glass/epoxy for strength. (2 sessions of glassing, each session had 3 layers glass)

For side areas around CB slot - couple of spots near the CB plate had cracks which made me nervous, so I ground out and glassed instead of just epoxy.

Next step is to fill and fair. I’m still working on improving my skill in optimal mix epoxy/fill/hardener to be able to shape these non-flat areas. I’m probably overkill I’d assume, but would love to hear others thoughts.

I’ll give more updates as I go.
Geoff

[GreenLake]

Nice update!

[BaltimoreChess]

Memorial Day Update!
Spent the weekend doing the below:
- some epoxy/fill work on the keel - still needs sanding
- epoxy/fill work to cover fiberglass crack repairs made at front end of centerboard trunk
- grinding out loose hull/deck sealer - there were holes/loose spots intermittently. used angle grinder and skinny cutting blades and fatter wheels (there were some "oops" along the way which I'll fix
- transom work included deck/hull seam and grinding off screw heads that were either rusted in place or were spinning in their holes. The ones loose in holes were below water-line - not great.

Pics included:
- deck/hull seam work
- epoxy and hull work/sanding overall (west system 105 epoxy/205 hardener, orbital sander 50 grit)
- transom with same deck/seam issues (ground out, using 3m 5200 to seal), and gap deck/hull lip for rudder post made by prev owners

Upcoming work:
- prime the bottom side before fresh anti-fouling - new anti-fouling will be West Marine/Petit CPP Ablative Antifouling "blue". ?? Working out now what kind of primer needed under this on epoxy spots.
- I correctly assumed there was some transom rot where there were loose screws below water-line. Current plan is to use some kind of hardener in the holes, then epoxy/fill to close them up, then I'll bore new holes in solid. ?Any recommendations on type of hardener to use? Interior was dark/mushy...
- lastly - Will repaint topside same sea-foam green. ?My plan is to prime first but maybe this is overkill?

More updates to come!
Geoff

[GreenLake]

This is a DSII. Therefore the transom should be a sandwich with plywood across the whole width. If I remember correctly what other DSII owners have posted here or elsewhere. The radical repair was to cut off the whole transom and rebuild. A localized "hardening" will most likely leave you with a hidden section of weak damaged plywood in the bottom half of your transom.

But I understand the appeal of avoidiing the most radical repair.

The quick and minimal fix would be to try to dig out a limited section. Just enough to support the screws for the lower gudgeons. You could use a bent nail in a drill to clear out some of the wood and replace it with a mix of epoxy and short strands of fiberglass, cut off from the edge of some cloth.

That would form into a plug that you can then drill for the screws. Or wax the screws and insert with epoxy still soft.

You can look into products like System Three RotFix to treat the surrounding wood before doing those plugs.

A slightly more thorough repair would be to slice off a strip of the existing transom between the drains. That would expose a larger area of damaged wood and allow you access to scrape out more of it beyond the opening. With some luck, you would reach a good fraction of damaged wood that way. That level repair is better at strengthening the transom to take the loads from the rudder, over just holding the individual screws. Even having a dozen square inches at full strength would be like having a big backing plate rather than relying on the strength of the outer skin of the transom.

A boat or wave that hits your boat from the side will put enough force on your rudder that it can break in the worst case. Happened to me. You don't want the transom to be the weak spot in that scenario. Taking on water is the obvious risk. So the task is to do more than just seat the screws.

Again, treat any wood you can't reach with the RotFix system. Then replace the wood you took out with some fresh plywood. Probably in sections and embedded in thickened epoxy. Overdrill the screw holes but don't fill yet. And then laminate to close the outer skin. For best result and strength the edges of the old laminate should be beveled. Finally, drill the screw holes. Fill with thickened epoxy through the holes and before it cures insert waxed screws.

You will be casting threads in place. Better than drilling.

Hope this gives you enough to plan your preferred approach.

[GreenLake]

I've most recently used Pettit EasyPoxy. They sell a high build primer that you can sand down for an even smoother suport. I genuinely like that paint. It wants a warm day or two to cure though and full cure is a week. Looks great and is super tough when cured. Do try it on something small first. To get the feel for it and how much to thin.

I've been brushing it on with tipping with a super high quality brush to help it level. For a full hull, you may want to roll and tip instead. Good luck.

[BaltimoreChess]

I did end up using the interprotect 2000e epoxy primer, did a great job but oof does it stink. Kids in attic could smell it, I’m sure my sense of smell will return someday . I did 3 coats of the ablative CPP anti-fouling. All in all very much worth the steps because the waterline/paint line on the boat had gotten inconsistent (not "one consistent" over previous years.

For the transom work, for this season I’m going to take the path of least resistance and gut/harden the internal transom elements around the screw holes, then epoxy/glass bits into the holes as much as I can get in there. The full tear out makes a lot of sense in long haul, I just don’t have the mental wherewithal and afraid that once I dig into that well lose the sailing season. I’m definitely keeping a pin in that for future work. Thanks Greenlake!

I’ll add pics once I get home. System is fighting me on that with the phone. Next up, Petit one part topside paint. I’ll have to remove old pinstripe first, which hopefully won’t damage paint enough to require priming.

[GreenLake]

Your phone also does some interesting autocorrect. Some of your statements, I'm not sure what you meant.

[BaltimoreChess]

Sharing updated pics of the hull now that sanding/painting complete on the topside. During the process I used a 3M "eraser" wheel to remove all the old/damaged pinstripe and "Oday" label, then light sand and used the Ezy Poxy Topside paint Sea Foam to match previous paint. I also added 3M 5200 sealant at deck/hull seam where there were some gaps as well. The gaps were especially bad at middle/top of transom. It appeared someone had either intentionally ground out a piece of the transom edge to make it easier install/remove rudder - either that or years of rudder post smashing transom on way up did the damage. I sealed this gap internally with a ton of 3m5200 and will try to gelcoat or glass on top of this to protect. (**that's my approach anyway - open to suggestions!)


Pending/next steps:
- Replace the centerboard uphaul/downhaul assembly (wire, rope, shockcord in cuddy - pulling board down/up) - wire seems to be in decent condition but might as well update since we're doing work.
- Insert pipe/PVC in hole from cabin/centerboard trunk that wire goes through - lots of folks on forum have indicated this is a common water-entry point. Question: Are folks using PVC glue or something to hold this pipe in place? I'll revisit forums for details tho...
- Flip boat back over onto upgraded trailer with 5-6 buddies...
- Do some light gelcoat repair on transom - previous outboards being used must have moved around and damaged down to the glass. Question: Do any folks put some kind of protective material on top edge of transom under outboard? I could see this being helpful in minimizing transom damage. Maybe thin marine plywood or white acrylic..

Thursday night/Friday morn - if we're lucky:
- Set up all the rigging and check for what else we missed!

[GreenLake]

Very nice!

Normally, 3M 5200 is one of those materials that's overused, sometimes in inappropriate places. But the deck-hull joint isn't one of them. That's a joint that never gets undone, and both the adhesive and sealant properties are required. Whether that also applies to the gaps at the transom is something impossible to judge remotely, so I won't be making unhelpful suggestions. But I will suggest that you don't apply gelcoat without some laminate backing.

There's a claim that gelcoat never goes over epoxy, but it seems that's not universally true. I'm sure you'll find pointers on the web on what to pay attention to to make that possible. Also, some epoxies work better. System Three used to market one for that purpose, but their newer ones may also work. If in doubt a small test patch is better than having to scrape off a failed repair.

If I understand the DSII we'll enough, that pipe helps seal the opening from the bilge and also helps with issues that some people have with the wire sawing into the fiberglass. For the latter, I wouldn't have thought of PVC pipe. Some people, I seem to recall, have replaced the wire by dyneema. In that case you want something like PVC to reduce chafe on the rope.

That replacement is a natural upgrade because dyneema is easily as strong and long lasting. I've seen it used on the CB uphaul on an O'Day Mariner, which is a bit larger and has a weighted CB so no need for a downhaul. However, there the weight provides tension, so the line can't float free and get wedged in the CB trunk. Read the old posts, many in the DSII section, to see if someone has something helpful and first hand.