Under deck mast support broken

Thread starter #1
Just picked up a nice Capri last week, third time out in light winds with the jib up I hear a cracking/ tearing noise. Much to my dismay the deck was cracking around the mast mount. We got back to shore with the jib and I removed the cuddy. The mast support glued to the underside of the deck had separated.

I'm on vacation and away from my tools... Any ideas? A marine epoxy to glue it all back together?

Thanks for any insights
Aw geez, I hate to be the bearer of bad tidings, but I think there might be something seriously wrong with the deck underneath your maststep for this to happen, especially in light winds. So, no, I doubt simply gluing stuff back is going to be safe for you. Some young captain posted here in the last few months about having the mast come down and the bottom end with step and screws swinging past his face, so this is very unsafe.

I've never had the displeasure of cracking it open there, and usually we hear about damage to that area after a stay gives way, but I'm wondering if the wood core "sandwich" beneath has rotted. Just guessing, but the boat is well built and that means over-engineered, so a failure like that could mean some serious structural problem.

Any chance the screws holding the maststep were very loose?? That's about all I can think of that wouldn't mean covert weakness, and with shock loading might cause cracking.

Sorry. We've got several good, in-depth threads about maststep failures with pics. Hit us back with some pics and I bet you can get some good advice here. :(
How loose are your shrouds? I do not think that the mast step is designed to hold the mast up, just hold it in place. In theory, the only real load on the mast step should be vertical.

Sorry, no real advice on what to do next without your tools handy.
If there is still time, maybe with a clear photo of the under deck, we may be able to help you determine the extent of the damage and whether it is repairable :confused:
If it is an upper deck failure, I remember someone posted, with pictures, how they repaired/replaced that area on their boat.

I found it, title is "cracks at mast bracket" date may 2010.
C14 mast support repair

I repaired one per the attached pdf. (It adds about 5 lbs.)
I forced & restored the damaged support to its original position and provided smooth, surfaces to attach the new parts. I used bolt & West epoxy, the bolts provide the clamping for the glue up). Make sure that the failed part is epoxied to provide solid base for the mast step. If too much damage, you may need to remove and replace
the broken part dircetly under the steel mast step.
I used white Marinetex to solidify the base and also provide the cosmetic fix to the deck around the mast step.
If you want to try this and wish to discuss (or if my pdf fails to attach) call:
Ross 805 371 4851
C14 Mast Step Repair

Unable to open this pdf file on my MacBook,
had a tough time deleting it too. Had to
force-delete it.
Hope it wasn't laced with a virus.
mast step fix pdf

I was able to attach the pdf drawing file but it does not open from the forum for me either.
I must have a bad procedure or maybe my Acrobat version is too old?
The file opens fine from my folder.
If you would like a personal email, let me know at rrera@roadrunner.com
I dont understand everything I know about this stuff!
I just went through this - again. The last time I tried to fix this, I removed the mast step bracket; drilled holes into the fiber glass and injected epoxy; and then will the cracks and leveled the surface with MarineTex. ...what a disaster. This only kept everything solid for a while, but then the mast step broke again and this time the mast nearly punched completely through the deck.

The correct fix, which I just ended up completing, was to get inside the boat; cutting the back of the fiberglass cloth (very thin) holding in the board under the mast step (very easy); getting a new board (I used white oak); sliding the new board in place; and fiberglassing the board back into the slot.

This should have gone easily - if I would have done it right the first time. Instead, because of all that epoxy I injected, I had to use a grinder to cut out the old board and cut away part of the the fiberglass under the maststep (since it was bonded to the board). After I got my previous handy-work removed, I was able to insert a new board; build up the fiberglass for the mast step; fair and smooth the new glass out to match the old glass; and then apply the topcoat to match. Ugh.

It pays to do it right in the long run. If you have the old-style capri with the splash rails, which is what I had, they are a source of water leakage if not sealed really well. If you leave them on (I removed mine), seal them and perhaps give that board a good coat of epoxy or waterproof sealer. I actually glassed my board before inserting it. It will be a bear to remove if needed, but water cannot get to it now - so I should never need to replace it again. (I hope)