Removed teak on GRP/bals sandwich, what next?

[Scotty_Tradewind]

Removed teak on GRP/balsa sandwich, what next?

I'm in the process of removing the very tired teak deck from my Tradewind.This has always been planned and was part of the budget when making an offer for the boat last year.

In some places where never open to any elements we can see she was laid originally with 9mm. In some places this has worn to 3-4mm, in other areas the teak has lifted slightly and has fine dark grey silt underneath.
It appears to have been laid on an epoxy mix and that which was bonded well has as expected, been incredibly difficult to remove. Once the top planking has been chisseled off, we have used an electric hand planer, belt sander, orbital sander and scraper to finally get through to the gel.
The GRP/balsa/GRP deck is fairly stong and we are still pondering as to how best proceed with making good. We have a few places to fill and tidy and want to add a little back to the strength as a precaution.
Teak is far too dear especially with the Tradewinds large deck area. The 'plastic' decking is still very expensive.

We've been toying with the idea of laying down epoxy or polyester with a glass cloth to help maintain the strength. If the deck was in fact weak we were also considering laying a 10mm sheet of GRP honeycomb directly onto the deck with epoxy and then a glass cloth to finish off.

Are there any other ideas?

 

[aluijten]

You could consider this:
http://www.marinedeck.net/

It's cork granulate bedded in some kind of resin. What I've seen from it, it's kinda nice but no personal experience.

Are you sure you need to add a layer for strength? Most teak decks on GRP boats are only cosmetic and serve no load-bearing function .

Arno

 

[Scotty_Tradewind]

Hi Arno,
as expected removing the epoxy has been patchy and in some small areas some of the gel will need making good. Therefore to add anything to make good might as well be stronger whilst we're at it.
One thing that had been mentioned and I'm not sure whether to believe, is that if we stiffen the deck too much then something else may take up the stressess and we may get cracking around the deck openings and edges because of it. Not sure if that's a feasable theory or not?
Many of the additional teak appearance coverings are fairly attractive but add no strength and would take me over my budget at present. I could consider finishing off the deck to a standard where that could be done in the future, if funds allow and if I feel the urge.

 

[Tranona]

Fill the craters and a skim coat of glass cloth set in epoxy, with peel ply to get a smooth surface. Apply a non slip coating - I have seen a couple of boats done with Kiwigrip that look really good. Might be worth talking to Wessex Resins (West people) for advice on the epoxy bit.

 

[snowleopard]

You could Artex it! No, not with the stuff they put on ceilings in the 70s but a stippled gelcoat. Mix gelcoat resin with thixotropic paste and 'wax in styrene' to give stiff mix. Brush on generously then stipple it with a sponge wrapped in polythene. It may form sharp peaks when cured and will then need to be lightly sanded to take the sharp bits off.

Practice with a few bits first!

 

[Scotty_Tradewind]

Thanks, interesting stuff that peel ply, where you can in fact get a non slip surface by using a coarser weave. It looks excellent for getting that flat surface. I found some good videos on 'how to' on youtube.
Gelcoat resin with thixotropic paste etc is a thought too... more research required I can see. I wish I had tme to go on a West Systems course.

 

[late-night-lochin]

Hi scotty

I doubt if the teak ever added any stregnth to your deck - only weight and worries.

If the teak was originally bonded on with epoxy then the old epoxy is probably stronger and better than the gel-coat below it.

If where you have sanded through the epoxy you have only danaged the gel-coat rather than sanded into the laminate it won't be a problem.

One problen is that whilst epoxy will bond to practically anything, polyester gelcoat wont bond well to epoxy.

I would suggest getting the old epoxy reasonably flat i.e. get rid of any lumps then paint it with an epoxy primer.

Then, fair in any dips with watertight epoxy filler, rub down and apply another coat of primer.

The deck should now be better than it was when the boat was new.

Finally finish with non-slip paint over an undercoat to the paint manufacturer's recommendations.

Keep the non slip colour as light as possible if you don't want to roast inside!

 

[rickym]

Scotty Tradewind,

PM Chippysmith of this parish. He did something very similar to his yacht last year. Removed the teak, then a glass/epoxy non slip finish applied. Looks very good.

 

[Scotty_Tradewind]

teak off what replaces etc?

Hi Rick
Many thanks PM sent.
If you know him any chance of giving him a call on my behalf?
ta
S.

 

[Blueboatman]

Re Late Night Lochin. Wot he says,hi-build epoxy primer is amazing stuff, why mess around with gelcoat, IMO ?
Unless the deck feels spongy in places( water ingress),or deflects worryingly ( some usually solid grp decks did from new but not I suspect, a Tradewind), then don't conplicate the issue by trying to add more cloth and resin !

Well done BTW, you've done the hardest part.

 

[Tradewinds]

Re Late Night Lochin. Wot he says,hi-build epoxy primer is amazing stuff, why mess around with gelcoat, IMO ?
Unless the deck feels spongy in places( water ingress),or deflects worryingly ( some usually solid grp decks did from new but not I suspect, a Tradewind), then don't conplicate the issue by trying to add more cloth and resin !

Well done BTW, you've done the hardest part.

What's the best Hi-build epoxy to use? I've used Jotun Penguard HB on my hull but it seems pretty 'soft' to me - sands away in the blink of an eye. Perhaps that's as it should be?

I'm interested because I will be doing the same to my deck in the next season or two.

 

[Scotty_Tradewind]

What's the best Hi-build epoxy to use? I've used Jotun Penguard HB on my hull but it seems pretty 'soft' to me - sands away in the blink of an eye. Perhaps that's as it should be?

I'm interested because I will be doing the same to my deck in the next season or two.

Hi Nigel
if you'r accross my way drop in and see the project.
I've just been given details of a chap on the Sussex east coast who has stripped off the teak and epoxied his Tradewind 33 deck.
I'll talk to him 2moro for the first time I hope, I'll ask him if it's o.k. to pass on his details.
cheers
S.

 

[Norman_E]

Be careful about using epoxy as a top surface, as some epoxies are not resistant to UV light, and a polyester resin may be better for that reason.

 

[Pleiades]

Removed Teak Deck

Hi Scotty,
why not just fill any holes then slap down Treadmaster? It can hide any imperfections and is very long lasting. The majority of the Tradewinds that did not have teak probably had full Treadmaster cover from new. There is no way a deck covering could usefully add any strength - the original build was usually far more than adequate and the Teak was only cosmetic. At least one earlier Tradewind did have signs of localised deck lifting at the chain plates where the outer stays come down on to the deck - this may be the case where the hull was home completed. So I would check carefully for any signs of that and instead of spending money on pointless expoxy covering I would if necessary add internal reinforcing support under the side decks.

Cheers,
Robin
Pleiades of Birdham
MXWQ5

 

[chippysmith]

Hi.. I'm away on boat at present, will get pm to you on my return.. My teak was structural so had to replace it with another layer of ply.. Was a good time to replace sub-deck so did that to.

Sheathed all ply pieces with slightly thinned epoxy, including bearers, bonded ply layers and screwed then layed it up with 300gm bi-ax then peel ply, then faired and two pack poly painted... Lovely job, stiffer than a stiff thing.. Painting was the hardest part!

 

[Tranona]

Hi Scotty,
why not just fill any holes then slap down Treadmaster? It can hide any imperfections and is very long lasting.

Trouble is, Treadmaster is neither cheap, nor easy to apply properly. "Slapping down" is not a good way of describing what is a laborious and time consuming job for DIY - although by the end you will have learned how to do it - and learned never to do it again. Bit like block paving your driveway.

Guess who has done both, and only once!

 

[Scotty_Tradewind]

When Treadmaster is brand new and well fitted it seems to work extremely well. My feelings are that within a few years it looks a bit tired and when old becomes tatty and appears DIY.
It is also not a cheap option. Although we all have our budgets I'm more intent on structural qualities of the deck first and foremost, closely followed by quality of finish.
One of the phrases used when I was teaching CDT/Design was that the finished article should 'look like a bought one'. If the deck is finished and yet is not noticed by others for its DIY appearance then I'll be pleased.

We've still to remove teak from side decks back to the stern deck with hammer and chisel and to remove the genoa tracks... a job I'm not looking forward to as the screws didn't want to turn even with an impact driver last weekend.

The large front deck is now clear of all its through deck fittings, hatches and teak. The chainplates came off o.k. with just two of them requiring a very large hammer to force up havong a nut to protect the end of thread, with my son having a jemmy topsides to lever as well.

Just some epoxy left in the runs where it adhered exceptionally well to the gel and teak. At very close inspection with a magnifying glass, the gel shows fine cracking down the lines of the caulking in places so that really reinforces my thoughts that an epoxy or polyester with glass cloth may be prudent to guarantee strength long term.

Tools/machines used so far..... Claw hammers, chisels with steel topped handles, mallets, 3 & 4"electric hand planers, 4 & 5" belt sanders using-60grit down to 120grit, 6" orbital sander- 60grit to 120grit, vacuums, scrapers, various ring and o/e spanners, box spanners with ratchet.

Luckily my yard, Wicormarne, has a huge lean-to shed where I have tenure 'til end of Aug, so even the rain cannot put things off until Sept..... but I'm off sailing in Turkey 23rd Aug for 10 days........ no pressure then!

What thoughts on deck so far?

S.

 

[late-night-lochin]

Not sure form your post but was the teak screwed down (and potentially breaching the balsa sandwich deck) or just bonded down with epoxy?

 

[Scotty_Tradewind]

Not sure form your post but was the teak screwed down (and potentially breaching the balsa sandwich deck) or just bonded down with epoxy?

Hi, it was in a few places only, mostly epoxied - and where it stuck it is very sound. Problem is it's also extremely thin in the places where most action has taken place on it. Screwing seems to have been done in recent years as a stop-gap repair.
The boat has spent most of her life in Greece and has been dry and well protested. There it had a lightwweight all over cover so water ingress has only been slight in the last couple of winters in the U.K. where it had other tarpaulins to keep out the worst of the rain.
There is a little water ingress into the balsa sandwich around the heads hatch but we think it only goes back a few cm's and we're going to enlarge that hatch space to fit a larger new hatch anyway.
The king plank down the centre of the foredeck had the most splits and screws and water ingress. From there water ran back under under the teak and not through the balsa and dripped through the inner forestay fitting. That was sealed during the winter as was a serious leak following a cable run from the front nav light cable. The cable ran through the pullpit tubing and straight through the deck where water simply followed the cable which had no deck gland. Luckily it seems to have just poured in and the balsa sealing was not effected and seems dry and sound there.
When surveyed we paid a lot of attention to structural strenth of the grp/balsa sandwich and so far we've not been disappointed.

 

[late-night-lochin]

If your balsa sandwich is sound your'e probably safe.

The deck should be strong enough as it. I'd be inclined to countersink any screw holes then fill them with fibreglass paste.

If the stress cracks are that fine, I wouldn't worry about these either - just continue as I recommended in my first post.

By the way, I wasn't necessarilly thinking of "high build" epoxy, just something with the consistancy of Gel Shield.

I know exactly what you are saying about "looking like a bought one" - just as long as it looks like it was bought from Thomas Chippendale and not Wickes!