Soft Core and Mast Step Repair

[Peter T]

All good mate. Here if you need me mate. Cheers

[Watto]

Some good toilet reading

https://www.westsystem.com/wp-content/u ... ritish.pdf

[Peter T]

Brilliant Luke, everything you could want to know. Thanks

[Andrew]

Thanks all,

[Andrew]

Just came across this informative lone epoxy post, from Pete via ozzie, mentions a deck repair and epoxy usage methods

viewtopic.php?p=8619&hilit=forums#p8619

[Andrew]

An update, it took awhile, bought WEST system epoxy ready to use as in Peters deck repair method.

Then bought an Air compressor (from "Supercheap Auto", a BR3000, 25%off) with beginners 5-pack of Ozito tools and 30m of ozito airhoses (preparing for the "drying out" phase). It's running well, 190 litres per minute, direct drive, 40L tank.

However it's a very wet wet season now. The new tarp is working well keeping her bone dry, however it's not high enough to work on deck. (slowly working on that issue, have 100m coil of 50mm HDuty poly pipe - arch shelter in mind) oh for a decent cyclone-proof shed.

This year i've looked into all other possible repair methods online. However reckon Peters is the best/"easy" method, it surely will last for decades. (most other permanent WEST epoxy methods are more complex, require one side of deck to be cut off, brand new ply core laid in then biaxial glass skin recovering..allot of work/cost)

Expanding Foaming with Australian available products was looked into. But suitable high density 2 pack injectable foams are hard to get up here. Mitre 10 had Soudal products. I online ordered Soudal "Fill and Fix" foam (36kg/m3) for fastening window and door frames, harder stuff but they sent ordinary "Gap filling and expanding foam" (25kg/m3) the stuff for around pipes through wall openings, which was on the shelves already. Both were one part, moisture curing types (ok if its a wet space to fill) It's the expanding foam found in most hardware stores. It's partially open celled, so can take up sea water (bad).

Sikaflex has "Sika156 2C" a 2-part in one-can product which could be better. But can't obtain any of this stuff, or get spec's on it online. It might be ok for repairing lower stress areas of decks? Only some of the 2 part epoxy expanding foams are closed cell and can be rigid enough, but their delivery is to just pour the cup pre-mix into a large hole, (only Injectadeck has developed a dual-syringe & mix delivery, its expensive)

My guess is that building codes must be stricter overseas, so the top shelf foams like Sika156 2C aren't used downunder much, if at all? A "structural foam" is what is required, maybe some aircraft engineers etc who use these specialist materials out there? There must be tons of glass old boats around requiring rotten core repairs.

[Peter T]

Hi Andrew. Just been having a read. If there is anything I can help you with mate just say.
Cheers

[Andrew]

Thanks Peter, I will do that when time comes (April?). It's a bit too hot, humid, wet and unpleasant outside for a few months up here in Townsville, probable not good for epoxy or old guy. So just keeping the boat as dry and mould free as possible under a snug tarp. Doing a bit of inside house painting in aircon now, (Have accumulated the epoxy etc to do it though, and its high on "the do list")

[Andrew]

Sunny April, and change of the seasons. Got a good run of dry weather again, so began the deck repairs.

Removed the tarp and mast from the boat, bit the bullet and drilled quite a few 6.5mm holes in the deck (the syringe end fits this size), on the cabin top and foredeck. Holes about 6" apart. There's no turning back now.. !

Blew out the holes with my air compressor. It was mostly empty void under the springy areas, a dry brown dust came out, some flakes indicate that it could once have been foam core but it was mostly pulverized to dust, gone. The core didn't get wet, things must have been sealed ok ( i had sealed the old 12v electric plug hole with sikaflex). The mast step always seemed solid, and the dry core implies that any wood strengtheners should be intact?

Did a re-read of this thread to refresh memory, learning. appreciate the input.
It's been drying over 24 hours,

Next steps,
Remove some deck fitting bolts..
Then tape up deck..
Make up dowel plugs..
probably start epoxy injection at lowest holes adjacent to mast step..do the strongest loads area (around mast step) first..

[Andrew]

All good mate. Here if you need me mate. Cheers

G'day Peter, Ozzie (and others who may have done this type of job before..or just interested in doing it) just a progress update on Teria's deck-core repairing.

I'm removing deck fittings and bolts in the areas that epoxy may flow into (don't want to glue the bolts in forever). Amazing how stuborn some of these deck through-bolts can be, after decades in place. So far have the mast tabernacle and the forward hatch off. Lots of labelled plastic containers for each fittings nuts n bolts.

The tabernacle looks fairly good (A previous owner aluminium welded a 4mm Aluminium plate to the bottom of fitting, as a few hairline cracks were on top base-plate near the front - boom vang attachment area). The fiberglass base of tabernacle looks intact as well, just a few gel coat cracks around bolt holes. The forehatch's hinge bolts had crushed a bit of the cabin top front as well (despite having Aluminium backing plates inside). Removed an old defunct poptop latch base. Taping up all holes underneath on deck heads.

Sometime ago I watched a utube video of a yachtie strengthening his cored deck with epoxy injection. His trick was to spray silicone on each bolt before bolting fitting back on, then the epoxy wouldn't bond to the bolt threads and they could be removed easily forever after. I might try this method. Because the holes won't need re-drilling again (avoid drill alignment problem). Has anyone tried this?

I'm planning to flow epoxy under and around the mast tabernacle, and also under the hatch hinge seat, and some staunchion bases, to beef them up for good. Might also remove forward bolts from side grabrails and try silicone spray trick before Epoxy. It's like painting, most of the work is in the prep.