To epoxy or not to epoxy ...

06/04/2010 23:52:16
Robin Szemeti
Hi .. been away for a number of weeks due to massive work overload .. but, got my eye back on boats and sailign again now :)

So ... if you remember (I'm sure you don't though ;) I had ripped the step plate out of my Merlin, so .. that has (eventually) been repaired after much thinking and careful cutting and gluing ..

before; http://picasaweb.google.com/robin.szemeti/Merlin3239Blitz#5438570652457964034

after: http://picasaweb.google.com/robin.szemeti/Merlin3239Blitz#5456049132761137362

So, .. now I have stripped the entire deck back to bare wood, re-glued a rubbing strake that had become detached (clumsy helming at the pontoon by me) re-glued numerous bits of trim .. and its almost varnish time.

I've gone for International Perfection Plus 2-pack as it seems to be tough and durable and has numerous good reviews .. the only real question is whether to apply it to the wood ... or put a couple of coats of epoxy on first. I would think a good quality 2 pack polyurethane over an epoxy sealed deck would be pretty durable ... but what about depth of colour and gloss? will it have that "look" that you get from several coats of varnish on a nice bit of stripey sapele or will it look a little more dull? I presume it will be totally durable for many years ... but I also know that once epoxied its not a simple case of pouring a bit of paint stripper on it if its "not right" ..

So .. whats the general opinion for a first class job ... epoxy and then varnish or just varnish?

07/04/2010 07:19:01
Richard Battey
Hi Robin,

Personally if it were me I would apply a couple of coats of epoxy, either SP320 or 106 followed by the international 2 pack or single pack Epifanes. This will provide a quick high build finish plus provide durability. Make sure though if using epoxy that you apply in the correct conditions, i.e. dry, dust free and a warm environment . As for depth and colour, basically the more coats you put on the greater the depth and finish.

07/04/2010 07:40:52
John A
I would have said (but i'm no expert) three coats of Blakes woodseal (UCP no longer available) as it really penetrates, leave for a week then epifaines, that was suggested to me by an ex merlin man who now builds the most beautiful wooden boats, the Spirit range.

07/04/2010 07:58:17
Chris M
Woodseal is good actually, but has no adhesive properties at all. SP Eposeal is the same. On a boat of this age you want two or three coats of SP 106 or 320. Put it on with a roller and heat it with a hair dryer as you go for maximum penetration.

Epoxy has structural properties as well as being a good primer and on a boat this age the deck may well be starting to have veneer problems you can't yet see. Better to glue them up now than have to strip it all off again next winter!

07/04/2010 09:30:20
Robin Szemeti
Thats convinced me then SP 106/320 it is.  I'll make extra extra sure I really have got a perfect sanded finish .. theres no second chances with epoxy.  At some point in its life it had been "professionally refinished" .. by a guy whose final finishing was done with a rotary sander (no, not an orbital .. a rotary, as in angle grinder with a sanding disc) ... I'm busily removing some extremely visible semi-circular marks, and it already looks a lot better, even just wetted out with white spirit it looks oodles better than before.  

As for conditions, I am not lucky enough to have the obligatory heated garage, but the boat has been sitting with a low-power electric fn heater in it for a couple of weeks, its as dry as a bone. I have a 10' x 20' pop-up tent/gazebo thing coming that should make a wind and dust free enviroment ... I'll just wait for a warm day and turn the fan heater well up :)

07/04/2010 09:37:14
Robin Szemeti
So .. for a Merlin, roughly, how much 106 should I buy for 3 coats? this will be deck, side decks and transom, but probably not the hull internals this year, thats next winters project!

07/04/2010 09:41:44
Richard Battey
spray water on the floor when varnishing as this will keep the dust to an absolute bare minimum. I tend to use SP106 only becuase it is a lot cheaper than 320 i.e. 1kg tin of 106 about £23 compared to 320 £38 and does the same job. Be very careful using white spirit as the epoxy could very easily react!! Must use thinners or acetone when cleaning the surface.

07/04/2010 09:49:09
Robin Szemeti
yep, it will be degreased with acetone,  the white spirit is just to wash out the paint stripper (methylene chloride).

07/04/2010 11:31:58
Jeremy kahn
Hi Robin... I have just coated my Spetember Girl in 2 coats of West Epoxy using the coating 207 Hardener (quite expensive)... I did all of hull and all of inside apart from under deck and on top of tank.... I started with a 6kg can and did a few repairs as well and still have about 1kg left so a 6kg seemed the best way to go and is significantly cheaper to buy in those quantities.... the best price I found was East Coat Fibre Glass Supplies up in Newcastle.... they were very helpful and supplied quickly.... she looks very pretty now!! Hope tht helps...

07/04/2010 22:29:44
Chris M
106 is cheaper, but remember it is not clear and nowhere near as UV resistant as 320. It's fine to use 106 for coating though, as the very slight colour change will be nothing compared with 25 years of sun bleaching just make sure it gets 5 coats of (Preferably) two pack varnish to protect it.

07/04/2010 23:34:44
Garry R
No one has mentioned sealing with G4 pond sealer before using Blakes Dura Gloss which is the route I have gone down for a number of boats and have found it to have worked well without it costing a fortune.  CVRDA have discussed this at length.

http://www.cvrda.org
07/04/2010 23:57:36
john
My advice, go for a 3Kg pack of SP320 (dont buy it from a chandlery), degrease thoroughly with Solvent A, its not much more and doesnt leave any residue (acetone will if you believe SP tech support, they're quite helpful). Before coating go over with a hoover then a tack rag. Tiny bits of dust/grease will leave craters and ruin your day.

08/04/2010 08:28:12
Chris M
The ther trick with both is to wash the area being treated with hot, soapy water. This gets rid of the wax that the resin exudes (320 is particularly bad for this, especially if applied in less than ideal conditions). Acetone won't touch it, nor will the "proper" solvent unless you use gallons.

12/04/2010 21:20:58
Robin Szemeti
So, I managed to get two coats of SP on today, wet on tacky, and  I measure it as roughly 600 microns, so theres enough of a coating to do the job. 

The only slightly worrying thing is .. its not what I would call "flat" .. it has a sort of orange-peel texture, not bad, but noticeable. I tried tip'ing off with a brush at 45 degrees, but it was determined to have the texture it wanted ... no matter how flat I made it with the brush, it happily re-textured itself within a few minutes.

Is this normal? Should I just flat it off with wet and dry and a bit of soapy water and give it a 3rd coat .. or just flat it off and apply the 2 pack varnish? I figure the varnish will have MUCH better self leveling properties anyway.

12/04/2010 21:36:32
Robin Szemeti
i should add, this is not full-on fish eyes .. where the coating has avoided something in the surface .. just a sort of unevenness, like what you might expect from a paint roller

12/04/2010 22:55:43
john
The resin was probably just starting to kick. When this happens it starts to go a bit like hair gel and ceases to level out properly. At 20 degrees C I would guess for fast hardener, mixed in something like a half pint plastic glass which has low surface area, that this starts to happen in less than 15 mins. If you have a fairly big area to do, its worth having someone else to mix for you in small batches. The quicker you get a freshly mixed pot down the better the finish. 

If your after a perfect mirror finish you will probably need to sand this lumpiness back to fair, if you go through the resin back to wood in any places whilst sanding you will in all likeliness need another resin coat.

The good news is that when you get round to varnish it is easier to get the finish you want.

Incidentally, if you using a 2 pack PU such as Epihfanes you need to work fast and always progress from the wet edge. What I mean here is that if you leave a bit you have varnished for for 5 mins or so, to do a bit somewhere else, then try go back and try to join the bit you did earlier with the bit you just did, you wont get a neat self levelled finish, you'll get orange peel at the join. This applies to small holidays too, if you miss a bit somewhere and have to go back, and you want a mirror finish, its going to be another coat and probably some sanding too.

I've probably done 7 coats in some places (but with lots of sanding in between!)

12/04/2010 23:31:11
Robin Szemeti
Well, I dont fancy trying to do it again anytime soon, so, I'll flat it off with 240/320 grit wet and dry. I doubt I'll go through to the wood, its not deep, its just sort of mottled, and I have enough SP left to do another coat if I have to.

Thanks for the advice, it seems I have lots of sanding to look forward to :)

22/04/2010 21:21:51
Robin Szemeti
progress:

http://picasaweb.google.com/robin.szemeti/Merlin3239Blitz#5463056647101596786

The epoxy was 'orrible to work with ... maybe its just a bit cold, but I kept getting 'fish eyes' no matter how much I degreased and scrubbed and sanded ... after 4 coats I gave up and flatted it off as best I could and went for the 2 pack PU

Now .. that is a delight to work with ... self-levelling, pulls itself flat nicely, sticks like well, sticky thing to the epoxy ... shineeeee .. I think 3 or 4 coats will sort it out, its already almost removed the last hint of fish-eye ripple, the next coat shoud solve it ..

http://picasaweb.google.com/robin.szemeti/Merlin3239Blitz#5463056647101596786
22/04/2010 21:25:05
Chris M
If you've used SP 106 you will want 5 coats for full UV protection. 106 is not as UV resistant as 320 and skimping on the varnish is a bad idea.

23/04/2010 08:40:29
johna
looks lovelly i'm about to start finishing 2717 decks having let the woodseal harden for 2 weeks, as i've got some 2pack blakes left from another job i thought 2 coats of that followed by 3 coats of ephaines one pot to build up the film

23/04/2010 17:47:40
Andrew M
Lovely job Robin.

The boat has to be from Laurie Smart, will be well worth the effort when you are back on the water.

23/04/2010 21:48:48
Robin Szemeti
Thanks, its going better and better .. got a second coat of 2 pack PU on, looks great now :)

Actually, she's Rowsell built (3239, Blitz), and Spud did a lovely job on it too.

Of course, I keep finding more bits to do ... water has got in to the err, flat bit that sit on top of the centreboard case, through the fittings at the mast foot ... and it has delaminated slightly (made from 2x 1/4" planks of mahognay, in a lovely curve) .. so thats got to be sorted out, or there will be tears when I pull some kicker tension on ... so thats all going to be stripped, epoxy filleted onto the front bulkhead and then epoxy sheathed and varnished.

24/04/2010 08:26:53
John
Robin, your fish eyes may have been dust contamination. After sanding I hoover extensively, then, just before coating go over the area with a tack rag (its a slightly sticky rag, I like the 3M tack pads best), this gets rid of the last few bits of dust.

I also tend to wear latex gloves for the final grit of sanding, to try and make absolutely sure that I dont transfer any grease.

If my epoxy is really lumpy, and I've lost the will or finance to sand back flat, wire wool works quite well for taking the shine off the epoxy in the pits that sand paper doesnt reach, prior to varnishing.

On the delamination front, sometimes drilling a hole the size of the end of a syringe , and an exit hole for air, and pumping epoxy in works quite well without being too invasive.

24/04/2010 14:19:32
Robin Szemeti
Hmm, it was all wiped down with solvent, I dont think i was dust, but there again, what do I know, it wasnt working for me and it obviously does for other people.

So ... the mast base/centebaord cast top ... water got in through the mast base fittings ...

http://picasaweb.google.com/robin.szemeti/Merlin3239Blitz#5463691240954203202
(scroll on for the next 3 pics)

Where should I drill the hole to inject the epoxy? ;)

I also found several blocks with split sheaves, so time for a bit of eBay shopping.

Just to be clear, I still think I got an absolute bargain on this boat, from a very nice chap at Cookham, and these repairs are just part of the fun of having a wooden boat and I'm still enjoying all the fun of working on it. I've got a Wayfarer to sail as well, so I'm not stuck without water based fun at the moment either.

http://picasaweb.google.com/robin.szemeti/Merlin3239Blitz#5463691240954203202
24/04/2010 15:02:44
John
Its always worth going over with a tack rag. You be surprised how much dust how much is on it. One spec of dust removed , one imperfection less. You can get oakey ones from b&q.

On the delamination front, you may need to get a bit creative. What I would do, and I'm not a pro, is:
clean out all the crap and old glue with whatever you can get in there
Hoover
Degrease with acetone on a brush
Put a fillet of epoxy with microballoons all along the gap and let it cure. this is so you can get epoxy to flow along the void.
Drill a hole at either end of the fillet, where you know there is a void behind, with a drill which will give a tight fit on a syringe
Mix up some epoxy and pump it in until it comes out of the other hole. Take not, epoxy goes off quick in a syringe held in you hand!

Good luck

24/04/2010 15:09:07
John
oh, and get some clamps on too.

25/04/2010 00:05:42
Robin Szemeti
I'll assume you meant microfibres insead of microballoons.

Anyway, what I intend to do is first re-glue the the lower laminate to the centreboard case and then re-glues the upper to lower laminate. Its not a complex gluing job compared to some of the others on here, theres no way I could have left it like it is though ... would have just snapped at some point during the year.

06/05/2010 18:21:25
Robin Szemeti
At last .. the final (almost) gluing operation on the centre board case ... just a couple of minor glue fills to do a little further back and an epoxy fillet along the front and its done ...

http://picasaweb.google.com/robin.szemeti/Merlin3239Blitz#5468205781879355346

The I can varnish that bit, another coat on the decks and .. *hopefully* its back on the water.

I also want to move the rear buoancy cushions a bit deeper ... at the moment, when it gets wet it floats with transom about 50mm below the water .. .which makes bailing a little difficult, and thats with us stood as far forward as possible ... so I recon the buoancy cushions need to be moved at least 100mm deeper into the boat to encourage it to float a little higher.

http://picasaweb.google.com/robin.szemeti/Merlin3239Blitz#5468205781879355346
06/05/2010 20:00:41
KM
Hi Robin,
It might be worth a little caution moving the bouncy cushions lower in the boat. The priority in that area may want to be the access to the rearmost toe straps. The low transom makes getting in easier and the excellent Rutland training taught us to get in and get going as quick as possible once the boat is up and bear away to sail it dry - no messing around with bailing. I've rolled out a few times due to missing the rear toe straps and I'm told the cushions do make a comfy seat on spinny legs. There's bound to be more opinions on the matter.

06/05/2010 21:29:59
Robin Szemeti
heh, OK .. I'll wait for further opinion on that one then.  Bailing was never actually attempted, mostyl due to lack of a bucket.  Transom flaps open bear away just resulted in a very slow progress.

the couple or 5 times we have gone over, we have never yet managed to get going again, the thing has remained firmly full of water and made as much progress as a slug in a tray of treacle, maybe I just need to try harder.

06/05/2010 21:46:16
KM
Suppose it depends on how much wind there is - maybe keep your capsizes for a 3 and above haha. We tried bailing out (the boat)once and realised a steady flow coming from the CB case was gaining on us, but not till after about 5 minutes - how we laughed! After loosing a couple of b+q buckets in subsequent capsizes we stopped taking them and haven't missed having them.
you made a wise choice glueing those delaminated pieces rather than sailing at the weekend - wouldn't want to dry that lot out again. it's looking great.

06/05/2010 22:01:12
Mags
Underwater transom is all very well if there is enough wind for you to speed away and use the flaps. But what if you capsize on a gentler day? It will happen!

06/05/2010 22:10:06
Smokin
It happens to us at Redditch all the time, you have no option other than to head for the beach!!

06/05/2010 22:36:54
KM
I think I remember someone having a 'sausage' shaped thing they put in the CB slot to slow the flow,  but the low transom is an issue - we've had to get back to the shallows with the boat completely full more than once on light days.

07/05/2010 08:57:43
Garry R
I had the "overflowing centreboard scenario" in a Proctor IXb and found that a piece of small diameter pipe lagging stuffed in the top of the CB case stemmed the flow enough to let you bale out faster than the water coming in.  I had it wrapped round the handle of the bucket.

07/05/2010 18:27:27
Mags
You stemmed the flow in the CB case with your crotch once, Garry! 

I think it best if the transom is a little above water, as the beach may not always be as near as it is at Redditch. If you have trouble climbing in, fit a loop of rope that can be flipped over as a 'step' to aid climbing in?

07/05/2010 18:46:34
Pat2121
Have the same problem with Half Cut and found that we have to block the ingress through the centreboard case with something - a piece of pipe lagging or just the crew sitting with thigh jammed along it. Then you have to back the jib to sail anywhere and keep it backed to compensate for the extra weight and turning moment behind the mast. We managed to finish a race at Roadford once like this, mainly because the safety boat didn't come out to us so we had to cope by ourselves. They got a right slagging off when we got in!

08/05/2010 09:16:25
Colin
When I started sailing it was usually the crew's T shirt that got stuffed into the centreboard slot....
Remember - a crew without a T shirt needs to bail harder to keep warm.

Colin

08/05/2010 09:43:00
david Henshall
back to the issue of epoxy - this return to winter is a complete nightmare as there is not enough warmth (even down on the sunny climes of the Hamble)to get the resin to cure properly. The boat is in the shed  but that is not heated and therein lies the problem - for good epoxy work, control of the temperature is important.

Good luck getting your work done Robert - looking forwards to seeing the pictures. I'll be taking shots of the work on 3025 (when the spring sunshine returns).

D

REPLY

Your Name
YouTube Clip
Paste the link provided by youtube under the "Share" button, looks like this "http://www.youtube.com/embed/XEsrho3jqbo"
REPLY
Type a Number under 35: