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Trying Hard
02-14-2015, 03:21 PM
Hi, I am a first time user, but have been a “Lurker” for quite a while but need some advice on below water line resin.


I am renovating a 16 metre jarrah yacht. Jarrah is an Australian hardwood. The short story is that white ants (termites) established themselves in the yacht. It was only after the yacht was hauled out and the interior was investigated that the true extent of the infestation was realised. The yacht was gutted, leaving an egg shell of 20mm jarrah external skin (it was the only wood the termites could not attack) and about 50% of the ribbing. A nests were found under each of the two sullage tanks. The boat yard instructed their employees not to touch the yacht, it was so fragile L


That was almost 4 years ago and the yacht is now ready to be put back in the water. Still needs cabin and galley fit outs, but everything is new, as in electrical, plumbing and hydraulics. The yacht has a hydraulic keel, jib and mainsail furlers. With keel up, she draws 1.2 metre, which is great for exploring river inlets.


Above the water line I have applied four coats of epoxy resin and the jarrah certainly comes up great. It still needs several coats of U.V. varnish prior to launching, but it looks exactly what it is, a wooden yacht.


My question is below the water line, with an area of approximately 80 sq. meters. The jarrah needs to be coated with at least 3 or 4 coats of resin, then fibreglassed prior to anti fouling. Epoxy resin is about 3 times more expensive than polyester. I understand that polyester breaks down in sunlight, is not structurally as strong or water resistant as epoxy resin, neither does it adhere to epoxy, where as epoxy bonds with polyester. I am thinking, to save on cost, and apply 3-4 coats of polyester resin to the jarrah, then use epoxy resin when applying the fibre glass matting? The anti fouling should block out the sunlight and the epoxy coated fibre glass should protect from water penetration.

Does anyone have any suggestions or past experience, on using polyester below the water line?

I am trying to upload photos of the "egg shell".

http://s1066.photobucket.com/user/nwmckay/media/Yacth_Oct2013_resize_zpsnbxifm5t.jpg.

SNAPMAN
02-14-2015, 03:26 PM
Hmmm, you have no doubt spent a great sum of money and time on your boat to this point, why try to save a few dollars this close to the finish line when you know polyester isn't as good as epoxy?

Alan
https://sites.google.com/site/helium12sofsailboat/

Phil Y
02-14-2015, 03:42 PM
Definitely epoxy, if anything. But I am worried. She'd have been caulked originally. If she's now to be finished bright, what have you done with the seams?

kc8pql
02-14-2015, 03:50 PM
I am thinking, to save on cost, and apply 3-4 coats of polyester resin to the jarrah, then use epoxy resin when applying the fibre glass matting?
A very bad idea. The adhesion of the whole layup will depend on the polyester, which has little to no adhesive properties. Use epoxy for all of it if you're going to
do this.

capefox
02-14-2015, 04:17 PM
All things considered in this case, polyester will cost you more in the end.

jackster
02-14-2015, 06:28 PM
Trying Hard,
Phil Y brings up a good point.
Assuming that that element has been addressed and that below the waterline has been faired and prepped, I don't see the need for 3-4 coats of anything prior to 'glassing the bottom.
The procedure is to coat the bottom with epoxy, apply the cloth while still at least tacky, and top while wet to fill the weave.
Should be less material intensive then your plan.
And, congratulations on putting so much hard work into an older wooden boat.
Any pictures available?
just my 2 cents. Cheers.

slug
02-14-2015, 10:58 PM
Polyester is really second class, go epoxy .

Fiberglass "Mat ". Is only used with polyester resin. If you use epoxy dont use mat, use fiberglass " cloth "

MN Dave
02-15-2015, 02:08 AM
Why on earth would you want to fiberglass the bottom of a good boat? Fiberglass coatings on wooden boat bottoms are used to extend the life of older boats that are too far gone for a cost effective 'proper' rebuild. All you have to do to start an argument on the forum is to announce that you want to glass a wood boat.

Wood tends to inhibit the cure of polyester resins, so they can't fully solidify right at the interface where...never mind, polyester will peel.

Trying Hard
02-15-2015, 09:39 AM
Hmmm, you have no doubt spent a great sum of money and time on your boat to this point, why try to save a few dollars this close to the finish line when you know polyester isn't as good as epoxy?

Alan
https://sites.google.com/site/helium12sofsailboat/

SnapMan you are correct. I think the saying is why spoil the boat for a halfpennyworth of tar. I think my deep pockets and very short arms were clouding my judgement. I have made the decision to go with epoxy.

Trying Hard
02-15-2015, 10:13 AM
[QUOTE=Phil Y;4449351]Definitely epoxy, if anything. But I am worried. She'd have been caulked originally. If she's now to be finished bright, what have you done with the seams?[/QUOT

Phil, Correct she is a carvel hull. The Jarrah planks are quite narrow and edge glued together there is no caulking. The planking runs at an angle of apporximatley 45 deg from deck to the keel . The rebuild of the hull was from the inside. With all the original wooden hull removed, and replaced except for the Jarrah skin. the Jarrah is bonded to the new "inner" hull with epoxy primer. The new "inner" hull is now 4 latice (crisscrossing) layers of 1/2" marine ply strips about 3" wide. Each strip has been coated with resin to further protect The reason for coating the outside of the hull with resin is to add strength to the Jarrah, and fill in the cracks and voids of the jarrah planking. Any small sections of jarrah planking showing obvious stress were removed and replaced. the Wooden Boat Restoration & Repair published by Gougeon Bros. - West System has been my constant companion and honestly I would have given up a long time back if not for that guide.

Sorry if this goes on a little and some terms are not correct, but I am a complete novice. I took the repair on as a challenge as the alternative was to strip her of all salvage gear, tow her out to sea and burn her. Her former beauty could not allow me to do this. Forgot to say this was supposed to be my retirement hobby. But still not quite ready to retire :-)

i will try an upload some photos.

Trying Hard
02-15-2015, 10:17 AM
A very bad idea. The adhesion of the whole layup will depend on the polyester, which has little to no adhesive properties. Use epoxy for all of it if you're going to
do this.

Thanks to the comments received I have decided to go epoxy. I needed some input. but nothing like a challenge :-(

Trying Hard
02-15-2015, 10:25 AM
Trying Hard,
Phil Y brings up a good point.
Assuming that that element has been addressed and that below the waterline has been faired and prepped, I don't see the need for 3-4 coats of anything prior to 'glassing the bottom.
The procedure is to coat the bottom with epoxy, apply the cloth while still at least tacky, and top while wet to fill the weave.
Should be less material intensive then your plan.
And, congratulations on putting so much hard work into an older wooden boat.
Any pictures available?
just my 2 cents. Cheers.

thanks Jackster. As mentioned in my reply to Phil Y. The reason for the epoxy resin is to fill int he small voids and cracks in the Jarrah that time has created (she is 20 years old). Really to make the Jarrah as strong as possible (if that is achievable - to work with Jarrah needs very sharp and quality tools - to the best of my knowledge it is Australia's king of iron wood.

When I coated the top side, it took 3 coats of expoxy as the wood was so dry. It simply sucked the epoxy in. In fact, next week, I am giving the top side another coat of epoxy before UV Varnish.

I will ask my wife what I am doing wrong when trying to upload photos.

Thanks for all the comments, I am really happy with the response.

Trying Hard
02-15-2015, 10:38 AM
Why on earth would you want to fiberglass the bottom of a good boat? Fiberglass coatings on wooden boat bottoms are used to extend the life of older boats that are too far gone for a cost effective 'proper' rebuild. All you have to do to start an argument on the forum is to announce that you want to glass a wood boat.

Wood tends to inhibit the cure of polyester resins, so they can't fully solidify right at the interface where...never mind, polyester will peel.

thanks MN Dave. Looks like I may have started a discussion on fiberglass coasting on wooden boat bottoms. I have not heard any comment before regarding not fiberglassing. I take Slug's comment about mat - cloth.

The reason to fiberglass, is exactly what you said MN Dave, I am/was trying to extend the life of the hull and assumed fiberglass was a reasonable idea? With a water line of 14 metres she's not exactly cheap to haul out.

jackster
02-15-2015, 11:31 AM
Trying Hard,
I cannot understand why one coat of West 105/205 wouldn't seal your Jarrah. From what I find, at 52 lbs/cu.ft., it is denser than White Oak at 47 lbs./cu.ft.,
unless it is totally devoid of any cell structure. In which case you would not be able to handle it enough to apply.
Also, I am confused (not an unusual state of mind for me) about how you repaired the hull. You say it was repaired "...from the inside..." with 1/2" ply layers!? Except for the ..."Jarrah skin..."
How did you do THAT!? How thick is this "skin" how is it fastened on?
The method you SEEM to describe I would consider cold mo(u)lded.
But, I must be missing something and you apparently are doing very well so far.
Keep up the good work.

Trying Hard
02-15-2015, 12:12 PM
Why on earth would you want to fiberglass the bottom of a good boat? Fiberglass coatings on wooden boat bottoms are used to extend the life of older boats that are too far gone for a cost effective 'proper' rebuild. All you have to do to start an argument on the forum is to announce that you want to glass a wood boat.

Wood tends to inhibit the cure of polyester resins, so they can't fully solidify right at the interface where...never mind, polyester will peel.

thanks MN Dave. Looks like I may have started a discussion on fiberglass coasting on wooden boat bottoms. I have not heard any comment before regarding not fiberglassing. I take Slug's comment about mat - cloth.

The reason to fiberglass, is exactly what you said MN Dave, I am/was trying to extend the life of the hull and assumed fiberglass was a reasonable idea? With a water line of 14 metres she's not exactly cheap to haul out.

Trying Hard
02-15-2015, 12:52 PM
Hopefully, here are some photos.http://s1066.photobucket.com/user/nwmckay/slideshow/Wooden%20Boat

Todd Bradshaw
02-15-2015, 01:00 PM
I cannot understand why one coat of West 105/205 wouldn't seal your Jarrah.

One coat of 105/205 doesn't seal anything. If you read and follow the instructions from Gougeon, they always suggest a minimum of two coats of epoxy, three coats if it will be sanded smooth, and if you want maximum water protection for something like barrier coating, you need about ten mils. Depending on conditions and application methods, that may take as many as six coats if you intend to sand it smooth before painting.

kc8pql
02-15-2015, 01:12 PM
Is this a cold molded hull? It seems to be from these photos from the OP's link above.
The answers will be different if it is.

http://i1066.photobucket.com/albums/u407/nwmckay/Wooden%20Boat/Yacht_18Aug_003_zpsuyualedr.jpg?186

http://i1066.photobucket.com/albums/u407/nwmckay/Wooden%20Boat/DSC00678_zpsrs78yyvb.jpg?206

http://i1066.photobucket.com/albums/u407/nwmckay/Wooden%20Boat/Yacth_Oct2013_resize_zpshejlbflc.jpg?190

jackster
02-15-2015, 02:06 PM
One coat of 105/205 doesn't seal anything. If you read and follow the instructions from Gougeon, they always suggest a minimum of two coats of epoxy, three coats if it will be sanded smooth, and if you want maximum water protection for something like barrier coating, you need about ten mils. Depending on conditions and application methods, that may take as many as six coats if you intend to sand it smooth before painting.

Granted that for a paint or varnish base with no 'glass to bind and thicken, multiple coats are needed, especially for some soft(er) wood planking. Say cedar, pine or mahogany.
I just seemed odd to me that, on a hardwood planking that is to be sheathed with some sort of synthetic cloth, any more than one neat coat before the coat to bond the cloth was unnecessary.
And the barrier coating in this case would be a paint product(s) over the 'glass layer. No?
I also think it is better to put that glass coat on the topsides to help reduce cracking and checking, especially with such a large surface area as this boat has, but that would compromise the varnished look.
That, at least has been my experience.

Phil Y
02-15-2015, 02:30 PM
Thanks for the pics. Wow, nice boat! Much work still to do too! Definitely epoxy and glass, but you know that now. Good luck maintaining clear coat in our climate. It can be done, but personally I'd rather be sailing:)

Trying Hard
02-16-2015, 08:34 AM
One coat of 105/205 doesn't seal anything. If you read and follow the instructions from Gougeon, they always suggest a minimum of two coats of epoxy, three coats if it will be sanded smooth, and if you want maximum water protection for something like barrier coating, you need about ten mils. Depending on conditions and application methods, that may take as many as six coats if you intend to sand it smooth before painting.

Todd. Above the water line Already has 3 coats of epoxy applied. By end of this week, after a light sand, she will have another two, giving a total of 5. Then UV varnish, most probably 2 coats.

Trying Hard
02-16-2015, 08:43 AM
kcs8pql

Yes, it is a cold mold hull. As mentioned before, the new internal hull is 4 layers of strip 1/2" marine plywood, laid at a basket weave design - best way I can describe, Each strip has been coated with resin to further protect from water penetration. I am hoping this will lighten her somewhat form the original estimate of 20 tonnes.

Trying Hard
02-16-2015, 08:59 AM
Granted that for a paint or varnish base with no 'glass to bind and thicken, multiple coats are needed, especially for some soft(er) wood planking. Say cedar, pine or mahogany.
I just seemed odd to me that, on a hardwood planking that is to be sheathed with some sort of synthetic cloth, any more than one neat coat before the coat to bond the cloth was unnecessary.
And the barrier coating in this case would be a paint product(s) over the 'glass layer. No?
I also think it is better to put that glass coat on the topsides to help reduce cracking and checking, especially with such a large surface area as this boat has, but that would compromise the varnished look.
That, at least has been my experience.

Todd, thank you for your reply. The barrier coating below the water line (mat or cloth) would be the anti fouling. I saw no reason to paint over the glass layer with e.g. a bonding primer. Now I am thinking of not glassing below the water line, in which case, may be i should use bonding primer ??

I seriously thought of glassing the topside, but as you say, it would compromise the varnish look. I did a small trial area with glass and it simply did not look right. As for cracks. The original Jarrah (about 20 years old) was sanded back - hence the light look in the photos. That took a lot of the surface cracks out, but not all. However, the epoxy has nicely filled in those. As I think I said before, the first two coats were very quickly "sucked" into the wood. I believe that 5 layers of epoxy resin and then 2 layers of UV varnish should be OK. It is my understanding that epoxy resin provides a bond stronger than the wood itself ? But again, I confess to be a novice and always willing to learn.

Trying Hard
02-16-2015, 09:04 AM
Thanks for the pics. Wow, nice boat! Much work still to do too! Definitely epoxy and glass, but you know that now. Good luck maintaining clear coat in our climate. It can be done, but personally I'd rather be sailing:)

Yup, I know now :-)

Tassie is on my list.

Just wear sunglasses when I let you know I am arriving. I bought the replacement engine from a Volvo agent close to Hobart.

StevenBauer
02-16-2015, 09:28 AM
I'm not sure two layers of varnish will protect the epoxy from UV damage. Maybe check with the varnish manufactures technical staff.


Steven

Trying Hard
02-16-2015, 11:07 AM
Trying Hard,
I cannot understand why one coat of West 105/205 wouldn't seal your Jarrah. From what I find, at 52 lbs/cu.ft., it is denser than White Oak at 47 lbs./cu.ft.,
unless it is totally devoid of any cell structure. In which case you would not be able to handle it enough to apply.
Also, I am confused (not an unusual state of mind for me) about how you repaired the hull. You say it was repaired "...from the inside..." with 1/2" ply layers!? Except for the ..."Jarrah skin..."
How did you do THAT!? How thick is this "skin" how is it fastened on?
The method you SEEM to describe I would consider cold mo(u)lded.
But, I must be missing something and you apparently are doing very well so far.
Keep up the good work.

Not sure if I answered all your questions. The response has overwhelmed me, and like you, confusion sometimes sets in http://forum.woodenboat.com/images/icons/icon11.pngI do not have a technical background but can understand the comparison you make between Jarrah and White Oak. If it is one thing I have learned from my introduction into Wooden Boats it is how much more I have to learn, but every journey starts with a single step.

I honestly never thought of the term, but yes it is a cold mold. This yacht is so full of resin that smoking is a complete no no.

I think I may have answered the Jarrah question. The first two coats of epoxy were "sucked in", very much like blotting paper. The Jarrah was obviously extremely dry. However, I am now confident of the number of epoxy resin coats the hull is to get - 5 in total. That it will be extremely strong. Geee, I am almost so confident of that statement that I could - almost ha ha - try and prove the theory with a good size sledge hammer - may be not a good idea.

As for building from the inside. The inside of the yacht was completely gutted http://forum.woodenboat.com/images/icons/icon9.png to bring it back to ribs and hull. About 50% of the ribs were taken out. Mostly on the port side as the two sullage tanks under each head were on the port side. The white ant/termites appeared to like the warmth of the sullage tanks and built nests under each. When demolishing the interior wood (I will get back to you what type of wood this was) from the hull, two distinct "highways" could be seen where they commuted back and forward with each other. Walking into the hull was, one step,very carefully at a time, on the metal beams attached either side of to the keelston?? As mentioned the yacht has a swing keel, which when retracted sits inside, for want of a better description, something that looks like the mouth of a an extremely sturdy metal mail box. This two sided "mailbox slit" protrudes through the hull and then a fair way up into the bilge area. Not sure the photos show it clearly, but the below hull metal protrusion is what the yacht sits on in its cradle.

Anyway. I now have an "egg shell" (the hull) into which I can walk, with great care, and push the remaining 20 mm Jarrah planking so day light can be seen either side of the bow.

Next step is to support the outside of the hull with lumber so it cannot be pushed outwards from the inside. Then the next step is to lay the first layer of 1/2" plywood strip, from the inside, and epoxy to the Jarrah. Keep the shape by internal lumber pressing the plywood latterly
onto the jarrah, which as i say, in turn has lumber on the outside stopping it from being pushed
out. 2nd, 3rd and 4th layer do the same except after 2nd layer of 1/2 marine ply there is now enough depth to the hull where the 3rd and 4th layer can be temporarily nailed to keep the shape. After that remove all nails.

After that, replace all ribs previously taken out ribs with a laminate of 6 x 3/4" marine ply

When that is done, install bulkheads (1" marine ply, resin and 2 pack undercoat) except bow bulk head which is 2" laminate marine ply from hull to deck.

End result is the hull is 2 cm = Jarrah + approx 5 cm marine ply = 7 cm. approx. 2 3/4 " and glued together with epoxy resin, Jarrah to 1st marine ply, and then resin 2nd to 3rd to 4th. With laminated ribs 4.5 " (11cm) every 650 cm. and 5 bulkheads. No nails or screws. For additional strength above the 1 " marine ply sole,(also resin coated) the yacht has 4 walls?? - excluding the bow "legal" watertight bulkhead - that tie into the new deck (that's another story) .

Then get some sunshine and start sanding/repairing outside of hull and coming up to 4 years later http://forum.woodenboat.com/images/icons/icon9.png

Phil Y
02-16-2015, 03:38 PM
Oh, somehow I got the impression that you had already replaced the inner laminations. Maybe you have. You are writing in future tense, but maybe you are describing what you have already done? If not, maybe this is a good time to have a good chat to a boat builder before you get in too deep. You have a heck of a lot of work and expense in front of you, and I am not at all sure you know what you are doing. Hope that statement doesn't offend. Good on you for your commitment. Epoxy degrades very quickly in sunlight, particularly in Perth. Even UV protected clear coat is really not much good. I think it might be Norglass, a good local product, who say even of their own clear product, Forget it. Certainly 2 coats will not take you anywhere. Seriously, you want to paint the hull. The planks go the wrong way anyhow:)

Why use marine ply for the inner laminations? It's probably the most expensive form of timber you can get. And if you are doing laminations set at 90 Degrees to each other, you end up with the directional strength of ply anyway. Just use ordinary timber planks, set at 90 degrees to each other. The New Zealanders do this very well.

I dunno, don't want to throw cold water on a huge project, but it's sad when these things run aground for lack of a bit of proper research and understanding.

Anyway, good luck with it!

Larks
02-16-2015, 06:13 PM
Good on you for taking this on, she's quite a boat and a big project for a first foray into boat restoration. But it's all about the journey and it seems that you're well and truly open to learning and open to advice so I've no doubt you'll find plenty of people on the forum here happy to provide it.

Just remember that all the advice in the world is only advice and it's coming from people who have no real investment in your project and no real first hand knowledge of the boat or problems that you are facing. So ultimately the decision on what you do will be entirely up to you - you just have to filter everything as best you can and decide which best suits your situation, budget, capability and expected outcomes.

My two bob's worth then - for what it's worth: I see she originally had bright finished topsides so I can understand your interest in returning her to the same, but in all honesty I'd have to support the concept of properly glassing and fairing the whole hull and giving her a white painted finish.

Not only is the epoxy going to eventually degrade in the sun regardless of what varnish you use, with the varnish also degrading and requiring constant maintenance (you'll never be able to park her somewhere and leave her alone if you go cruising and want to fly home for a while), the very dark colour of the jarrah will absorb a lot of heat and not only accelerate the degradation of the varnish and epoxy, but will also cause quite a bit of movement in the timber in expanding and contracting causing the epoxy to crack and possible delimitation from your inner skin.

Also have a think about your internal skin a little more, as Phil said the ply is already multidirectional in its layup so think about what you are trying to achieve with how you do your inner skin and what may be the easiest and least wasteful way of laying it down. The more important aspect will be to overlap joins.

The shell that you create could create quite a strong monocoque construction so it may pay to have a chat to a Naval Architect to see just what way to best lay the inner skin to achieve the best bang for your buck, and also to see what framing you really need to reinstate as you may be able to save some time and money there with somewhat lighter frames than original, whilst still having a potentially stronger hull than original.

Sourcing timber in WA is certainly a challenge so I can understand why marine ply would appeal, but it will need to be good AS standard marine ply for this sort of job with no stinting on the cheaper stuff imported from Asia which is potentially falsely stamped with the BS standard (it seems that no one outside of Britain actually checks the BS graded ply so the stamp is applied as a bit of a bluff and potentially a false claim - OK for dinghy but not for a yacht of this size and potential value). The other option may be to price up cedar strip through Cedar Sales who have a distribution in Perth. I'm not sure how it will compare in price but it would be worth the exercise of checking - it would be a lighter finish (weight wise) and the bonus would be that you could bright finish (varnish or oil) the interior. You'd probably do one layer in the opposite diagonal to the jarrah and the final intrernal layer horizontal.

MN Dave
02-17-2015, 01:50 AM
in post #9 I asked why you would want to glass a wooden boat. You are not fiberglassing a traditionally constructed wooden boat. You are talking about sheathing a cold molded boat that is not currently a good boat, but may well be a very good boat in the end. Glass might make a lot of sense, and the question might be why not glass the entire outside? 60" wide cloth (http://thayercraft.com/7781.htm)might keep the overlap between strips of cloth well below the waterline, and the 8h satin is easier to fill and finish. The weave will not be visible from more than a few feet away with one or two layers of glass and a total weight of glass of 10 oz or less. I don't know where to draw the line, 6 oz is almost invisible, 12 oz looks decent, but a third layer of 6 oz is getting murky. Two coats of good UV resistant PU varnish should protect the epoxy for as long as the varnish is in good condition. Maintenance is always the key to preservation.

You have an interesting problem keeping the hull fair while you get the inner laminations in place. The skin should be reasonably stiff, but you weight will distort the hull and the laminations will tend to lock in that distortion, so you need to avoid putting unsupported weight on the hull as you work on it. Some sort of scaffolding? It sounds like you do have a plan to support the outside. Glass on the outside could help stabilize the hull considerably as you work and subsequently make fairing more difficult. Lots to think of before you start.

You don't want any gaps between the layers of strips, so plenty of lightweight filler would be a good idea. On a project this size you will do better with bulk materials than the brand name packages. I the states, there are places like this (http://douglasandsturgess.com/mm5/merchant.mvc?Screen=CTGY&Store_Code=DAS&Category_Code=FILLERSTHICK-LIGHTWEIGHT), and in the UK this (http://www.ecfibreglasssupplies.co.uk/p-765-glass-bubbles.aspx) and this (http://www.cfsnet.co.uk/acatalog/CFS_Catalogue__Glass_Bubbles_403.html), but I don't have a link for Australia.

Trying Hard
02-17-2015, 10:01 AM
Oh, somehow I got the impression that you had already replaced the inner laminations. Maybe you have. You are writing in future tense, but maybe you are describing what you have already done? If not, maybe this is a good time to have a good chat to a boat builder before you get in too deep. You have a heck of a lot of work and expense in front of you, and I am not at all sure you know what you are doing. Hope that statement doesn't offend. Good on you for your commitment. Epoxy degrades very quickly in sunlight, particularly in Perth. Even UV protected clear coat is really not much good. I think it might be Norglass, a good local product, who say even of their own clear product, Forget it. Certainly 2 coats will not take you anywhere. Seriously, you want to paint the hull. The planks go the wrong way anyhow:)

Why use marine ply for the inner laminations? It's probably the most expensive form of timber you can get. And if you are doing laminations set at 90 Degrees to each other, you end up with the directional strength of ply anyway. Just use ordinary timber planks, set at 90 degrees to each other. The New Zealanders do this very well.

I dunno, don't want to throw cold water on a huge project, but it's sad when these things run aground for lack of a bit of proper research and understanding.

Anyway, good luck with it!

Phil Y. I have completed the lamination. Sorry if I confused the issue. The yacht will be going into the water once the external hull is epoxy coated and that was the reason for my initial post to sound out what external coating I should use. I will seriously take on board your suggestion about painting. I have also read with interest all you have written and thank you so much. I am cetainly not offended.

Trying Hard
02-17-2015, 10:28 AM
Good on you for taking this on, she's quite a boat and a big project for a first foray into boat restoration. But it's all about the journey and it seems that you're well and truly open to learning and open to advice so I've no doubt you'll find plenty of people on the forum here happy to provide it.

Just remember that all the advice in the world is only advice and it's coming from people who have no real investment in your project and no real first hand knowledge of the boat or problems that you are facing. So ultimately the decision on what you do will be entirely up to you - you just have to filter everything as best you can and decide which best suits your situation, budget, capability and expected outcomes.

My two bob's worth then - for what it's worth: I see she originally had bright finished topsides so I can understand your interest in returning her to the same, but in all honesty I'd have to support the concept of properly glassing and fairing the whole hull and giving her a white painted finish.

Not only is the epoxy going to eventually degrade in the sun regardless of what varnish you use, with the varnish also degrading and requiring constant maintenance (you'll never be able to park her somewhere and leave her alone if you go cruising and want to fly home for a while), the very dark colour of the jarrah will absorb a lot of heat and not only accelerate the degradation of the varnish and epoxy, but will also cause quite a bit of movement in the timber in expanding and contracting causing the epoxy to crack and possible delimitation from your inner skin.

Also have a think about your internal skin a little more, as Phil said the ply is already multidirectional in its layup so think about what you are trying to achieve with how you do your inner skin and what may be the easiest and least wasteful way of laying it down. The more important aspect will be to overlap joins.

The shell that you create could create quite a strong monocoque construction so it may pay to have a chat to a Naval Architect to see just what way to best lay the inner skin to achieve the best bang for your buck, and also to see what framing you really need to reinstate as you may be able to save some time and money there with somewhat lighter frames than original, whilst still having a potentially stronger hull than original.

Sourcing timber in WA is certainly a challenge so I can understand why marine ply would appeal, but it will need to be good AS standard marine ply for this sort of job with no stinting on the cheaper stuff imported from Asia which is potentially falsely stamped with the BS standard (it seems that no one outside of Britain actually checks the BS graded ply so the stamp is applied as a bit of a bluff and potentially a false claim - OK for dinghy but not for a yacht of this size and potential value). The other option may be to price up cedar strip through Cedar Sales who have a distribution in Perth. I'm not sure how it will compare in price but it would be worth the exercise of checking - it would be a lighter finish (weight wise) and the bonus would be that you could bright finish (varnish or oil) the interior. You'd probably do one layer in the opposite diagonal to the jarrah and the final intrernal layer horizontal.

Larks. Thanks for the input. It's looking like the majority go with glassing and painting the whole of the hull. May be I was being too romantic rather than praticle wanting to keep the Jarrah exposed. As mentioned to Phil Y, the marine ply internal skin is already installed as are those ribs that were removed because of the white ants/termites. So not much I can do there but I am confident of the integrity of the new hull. As per the original hull she still has 20 ribs spaced at 650 mm. The 5 bulk heads are also installed where the previous one were installed. In fact all I have really done is copy and replace not try and change. or modify from the original.

Trying Hard
02-17-2015, 10:34 AM
MN Dave. Looks like I really confused everyone. The hull is complete. You are correct, I did use scaffolding to keep the hull fair while repairing and must say, it worked OK. Glassing should not be a problem as the hull is now sound.

Trying Hard
02-17-2015, 10:50 AM
Guys thank you so much for the valuable advice you have given me. I will now seriously consider glassing the whole of the hull and paint. In summary, I should have sought your advice earlier, but that's hindsight. I do believe the hull is sound as all I have really done is replace old with new and not tried to modify the original design. I apolgise for the confusion I caused if the past tense was mixed with the current. I will keep this post open and upload photos as I go along - especially the launching which I hope will be May this year |:)

Phil Y
02-17-2015, 03:11 PM
All good. I don't see any problems with the marine ply internal skins, I'm sure she's tough as. Next question. I think you said you plan to launch soon, then complete the interior fit out. Might be best to keep her out of the water until finished for a whole lot of reasons. I guess a lot depends on where she is now, where she will be moored, where you are etc etc. but all other things being equal, you are probably better off on dry land with your truck or whatever parked right alongside.

Trying Hard
02-18-2015, 11:58 AM
Phil Y

I get a pretty good deal on use of the "hard" (it's an industrial bit of land by the water) but have been there much longer than intended. The owner has been understanding but wants the area to do his own thing.

Everything below the water line (skin fittings, transducers etc) are installed. Although waiting for two cutless bearings for the P bracket and through stern fitting (got the ice and liquid soap ready for that). Everything below the cabin sole is also complete. All 12v and 240 v. cable is installed above the water line (just in case) and in separate conduit and 240 V GFCI?? circuit protection.

The only thing left is carpentry of the cabins, saloon and galley and installing lighting to already in place 12v wiring. The heads are installed and all above water line skin fittings completed. Ah, wheel house instrument panel needs display screens and switches attached to already installed 12v wiring/circuit breakers/fuses.

With help (finishing carpentry is beyond me, as was electrical, plumbing and climbing the mast). Paying bills seem to be what I am best athttp://forum.woodenboat.com/images/icons/icon6.png I think a lot of the carpentry can be all but done before launching. Which leaves the external preparation of the hull and the reason for starting this thread and for which, again, I thank everyone who took the time to reply :-)

Of course, we have not yet touched on anti-fouling but may be I can start a different thread on that http://forum.woodenboat.com/images/icons/icon7.png But before doing so will scour the site as I am sure that topic has been well and truly debated.

Phil Y
02-18-2015, 03:02 PM
Dont worry, you will get pretty good at antifouling.