Coelan Options

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narcer

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Having recently purchased a tin of Coelan clear gloss, I am wondering about the options on what is compatable to go underneath? Has anybody experimented with anything else other than of course the recomended Coelan Primer which will cost my other arm and leg. From what I have read about Coelan high gloss topcoat, you can use this product to cover almost any material - including plastics and aluminium? Maybe you could just use a normal varnish first or a stain (I will be using this on mainly teak trims - outside the vessel). Would much appreciate any advice/experiences with this product.
 
You really need to use the primer, that is the UV barrier, the top gloss, is just that, gloss. It offers no UV protection. You can put it on over other coatings, but why? Destroys the purpose of the stuff, it breaths, so will let moisture through to destroy the coating underneath, IMHO use the primer, it is only half a leg!
 
Absolutely agree with that. You must use the primer, and use it on clear, bare, wood.

I've used the gloss to stop a drip from a deck prism - very effective but needs renewing every couple of years, whilst some of the stuff applied over wood with the right primer is now up to 12 years old on my boat and still OK.
 
It is definitely good stuff, been on my masts now for 6 years, still excellent! I kept putting the primer on, until it wouldnt soak in anymore!!!
 
Presumably as with other products the quality of the finish is only as good as the initial preparation and subsequent rubbing down between coats, or is this less labour-intensive?
 
This is what I now reckon:

1. Get all woodwork clean, dry and well sanded. Coelan goes on very well over other polyurethanes like Sikaflex, and over epoxy, but, whilst it will go on over other finishes its bond to the wood will only be as good as the underlying substrate – it bonds better than most finishes itself.
2. For some reason the makers are obsessed with 80 grit sandpaper – this is definitely on the coarse side for yacht brightwork. Finer grits are OK.
3. Be very sure about the moisture content of the wood before applying the primer. Low is good. If it is at all high you are wasting a fortune.
4. Apply the right primer – yellow for teak and softwoods – red for mahogany, brown for oak. Be careful picking out the tins – they look almost identical.
5. Always thin the Coelan. Generously! Use el cheapo brushes as it flats out and loses brushmarks better than varnish, and you will spend a fortune on the thinners if you try to clean a decent varnish brush after using it on Coelan.
6. DO rub dowm between coats – the makers say “no need” but you will get orange peel if you don’t.
7. 10 coats.
8. That’s about it – after a few years the surface will be less glossy, due to minor abrasions, and a rub down and recoat will brighten it up again. Any small holes should be patched, at least annually or moisture will start to creep under the coating.
 
I dont rub down between coats, but do before the last couple, seems to do for me. 80 grit is to make sure the dust is a little larger, making it easier to remove/blow away, therefore not blocking the pores/grain of the timber, allowing the primer to penetrate and bond better. Thats according to the makers, I asked them, because as you Mirelle I thought it a bit coarse.
 
Is that one coat of primer and then ten of the final varnish? Is the primer thinned generously, or both the primer and final varnish? When you say 'generously', what is the final ratio, approximately, product to thinner? Which thinner should I use? Sorry for all the detailed Qs which would probably be obvious from the tins but I don't have any product available so don't know what to order. Many thanks.
 
Thinners is for top coat only, primer is very thin to begin with two or three coats of primer is enough, not sure what mirelle uses, but they reccomend no more than 10% but I've used 25%.
 
Many thanks, both of you. I really want to bring our rails up, it'll make a huge difference to the boat.
 
Some great tips there guys, thanks to you all. Just thinking...80 really is coarse but I can understand this only for the surface of the timber initially and then of course after this as long as the surface is kept flattened back with a fine key I would imagine you´re on a winner!
Thanks!
 
I am refitting my boat and not being very sucessful using epoxy to seal internal wood, (its like painting with treakle) so would this coelan be suitable as an alternative, and how does the cost compare with epoxy?
 
I will probably be shot down in flames for daring to suggest this, but I find that epoxy seems to work OK for an initial sealing coat on to timber, and especially plywood, if it is diluted down a bit with acetone. It then spreads much more easily, and soaks into the outer layer of plywood very nicely. Although I am sure it is not advisable to do this if you if you are bonding or laminating sections of timber together......
 
Well I had meant to do my teak decks during the summer....where did it go?? is there still time this year, assuming a few dry days would my decks be dry enough?
Will coelan fill or bridge fine gaps? I'm thinking of where the caulking is not adhering well to the side of the teak groove, I dont mean a ruddy big gap full of muck but those which you cant really see but still seem to leak!!
 
I re-did all the "iffy" seams in the teak decks before applying Coelan. It does not take long, and seems to have been worth while. I used Sikaflex DC and its primer.

Coelan is not a gap filler - it's a vapour permeable, flexible, membrane, so I would think it would bridge the gap rather than get into it.
 
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