Mast Collapse

justsomeguy · Jun 10, 2014

suvh8er said:
Hello everyone, bad news on my Mac's second trip out. While at the dock I was tugging on the bow line which unbeknownst to me was pulling horizontally on the turnbuckle securing the forestay. The brass turnbuckle snapped and my mast collapsed to the starboard/stern right on top of the raised pop-top. I was able to lower the pop-top and free the mast with some help but the damage was done. The first pic is looking aft from the front of the step, the second pic shows where the bolts tore out (circled in green).

The mast step partially ripped out of the deck and was also bent. I think I can hammer the step back into service on an anvil but I'm not sure about the best way to go for the fiberglass repair to the deck.

Should I carve out a bunch of the old glass/ wood and lay in some fresh glass/resin (I am concerned about possible delamination)? Should I just repair the damaged areas? Can the mast step be relocated a few inches fore or aft?

Brass turnbuckle?

My Mac 25 mast step had probably experienced something similar, although not a forestay failure. Likely a mast raising/lowering that got away from the PO.
I had to replace the step.

Not too difficult a repair, as fiberglass can just be ground down and replaced. The toughest part was matching the existing gel coat.

This repair will also give you the opportunity to install a mast plate, instead of those deck-mounted stand-up blocks, to turn your halyards and reefing line(s) back to the cockpit.

I'd try to keep the mast in the same position. How is the mast, by the way?

Doc_holiday · Jun 10, 2014

I'm really sorry about that! I was putting mine up solo once and lost the forestay I ran back to catch the mast and I did but I could have been seriously hurt. Fortunately I reduced the energy enough that no damage (other than ego) occurred.

I hope your mast is OK. You may want to bite the bullet and have a local fiberglass guy do the repairs since this involved the wood core.

crpdm · Jun 10, 2014

I am not familiar with the 25, but it looks as though the mast compression post is removable. If so, you could fabricate a stainless steel backing plate to mount beneath the mast step bracket. Then re-install/re-bed the mast step. Seal any cracks in the gel coat with gel coat paste. Digging into the wood cored fiberglass seems like over kill to me.

MrBill_FLL · Jun 10, 2014

can we see some pic's of the mast?

That's the only thing that could be hard ( and costly) to fix. glass work is not too tricky.
see finding41's thread... lots of nice work there.

count your blessings, it could have been worse...

justsomeguy · Jun 10, 2014

suvh8er said:
Justsomeguy, how is the mast plate setup you described different from my setup ( besides moving the blocks)?

The previous owner installed the brass turnbuckle! Obviously it was a pos! I have a SS one now to replace it. I will have to check on the mast when I get home but as long as its straight I should be good to right?

Doc Holiday I am pretty experienced with glass/resin repair. I was thinking about ripping out the affected wood and laying several layers of thick glass and expoxy...

Here are a few photos. The mast plate minimizes deck penetrations.

MrBill_FLL · Jun 10, 2014

Glad to hear the mast is straight!!!

as you plan your repair you might want to browse the treads on gas strut for the poptop, and the mast plate. -while you are in there...

do you keep it in the water or on the trailer?

set up properly these boat sail pretty nicely....

topcat0399 · Jun 10, 2014

suvh8er said:
Hello everyone, bad news on my Mac's second trip out. While at the dock I was tugging on the bow line which unbeknownst to me was pulling horizontally on the turnbuckle securing the forestay. The brass turnbuckle snapped and my mast collapsed to the starboard/stern right on top of the raised pop-top. I was able to lower the pop-top and free the mast with some help but the damage was done. The first pic is looking aft from the front of the step, the second pic shows where the bolts tore out (circled in green).

The mast step partially ripped out of the deck and was also bent. I think I can hammer the step back into service on an anvil but I'm not sure about the best way to go for the fiberglass repair to the deck.

Should I carve out a bunch of the old glass/ wood and lay in some fresh glass/resin (I am concerned about possible delamination)? Should I just repair the damaged areas? Can the mast step be relocated a few inches fore or aft?

That's some pretty minor damage if you ask me. Glad you are ok.

If it was mine I would just pot those holes up (to seal the core), redrill, countersink, and reinstall with bedding, new bolts, large thick fender washers and the rattle plate "justsomeguy" describes. The damage would hardly be noticeable if at all.

Many folks have a tabernacle that's a little benty. Most of the force on the step is in compression so a tabernacle with benty sides is really a cosmetic issue.

I wasn't so lucky, when the mast step bolts rotted out on ours in a previous life all kinds of water got in that core and I had to replace the entire cabin top
core and glass area under the mast step and pop top stanchion seats.

ymmv

trainmanjess · Jun 10, 2014

hello all

glad your ok.... and your mast too.... last year about mid summer, I was sailing with my son and a friend, and the shroud wire end fitting broke.... we were in the middle of a tack, when the mast came down into the cockpit between my son and me... scared the crap out of my son.... he was angry for over an hour... my mast bent in half, and then when we were hauling it back up on the boat, it flexed and broke into 2 pieces and tore into the main sail... needless to say, we were lucky no one was hurt...

it ended my sailing last year....

I could not find a replacement mast, unless I ordered a new one... couldn't afford a new mast at the time... luckily I found another sailboat, and bought it.... I decommissioned my Mac25, stripped it down, and it is now a kids pirate treehouse....

I know own a 1967 Kittiwake 23, and a 1971 Morgan 35.... both are wonderful full keel boats... hope you get back out on the water soon.... happy sailing

sincerely
Jess

Tsatzsue · Jun 11, 2014

The deck under the plate looks fine. I would just remove the plate and give the deck a good inspection. From the pics it looks solid. Just smooth out the surface, recess router out the holes so that the wood core is hollowed out between the fiberglass. Tape the bottom and fill with West Marine Epoxy. Once set drill out the new holes. Use an aluminum plate on the inside. You may have to shorten the mast support to accommodate the plate but well worth it. You were lucky there was no plate or you would have a lot more damage.

That is always a fear of mine. Good save!!

justsomeguy · Jun 13, 2014

suvh8er said:
Just Some Guy- is that the mast plate that is securing your halyard blocks? I wonder if I could make something like that out of an old aluminum road-sign...
.

Yes, it's a good solid place to mount the halyard, reefing and topping lift blocks, and boom vang.

http://garhauermarine.com/catalog_process.cfm?cid=68

Not too expensive.

MrBill_FLL · Jun 13, 2014

pretty sure that plate is SS.
I wouldn't trust a alum sign to hold halyard working loads. (vang, outhaul, reef, etc) -ymmv

if you kept it in the water you might want to do things differently than if you launch each time. - like a roller furling.

justsomeguy · Jun 13, 2014

suvh8er said:
Just some guy,
Which one of those plates did you use on your Mac? Looks like a few different sizes.

Another thought I had while I was sanding away at my patch, was why not just rivet some eye-straps directly to to the tabernacle and shackling the halyard blocks to that?

If you measure the ODs of your tabernacle, you'll be able to figure the size plate you want.

Rivets? No, I don't think so.

justsomeguy · Jun 13, 2014

suvh8er said:
Just Some Guy,
You don't think stainless rivets would be strong enough to hold those blocks? Most the hardware on my hobie cat is secured via stainless rivets.

No, I don't.

But, I could just be too cautious. What's the worst that could happen?

Sock Puppet · Jun 15, 2014

Don't know if it matters to you, but this may be a good opportunity to buy the updated mast step from Blue Water Yachts that will allow the use of a mast raising system. They aren't terribly expensive, and you're going to be into it anyway.

Mast Collapse

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