Should I epoxy coat or not?

Rivers & creeks

Rivers & creeks

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The antifoul is being slurry blasted off in a couple of weeks so before priming the hull we have the opportunity to epoxy coat it - but should we?

I think I remember seeing the opinion that epoxy coating an old hull can do more harm than good. The boat is 1977 and hasn't the slightest visible sign of osmosis, and none observed by the surveyor 18 months ago. It has been wintered ashore most years since new and will be wintered ashore alternate years with us.

What are your opinions? And if it really is a good idea what's the likely quantity needed for a 32ft waterline long keeler?

Thanks. Simon
 
If the hull has no osmosis or porosity, there is no real need to apply epoxy coating. The epoxy will no cause harm; the only problem is that the epoxy coating will lock inside the hull any moisture; this in turn may cause problems. Hence the hull must be bone dry.

Personally, I can not see any real benefit unless there is a specific reason to overcome porosity or for cosmetic reason . If you apply epoxy you may as well apply combine epoxy and copper to give you a long term antifouling solution.
 
Similarly, been thinking about coppercoating my 40 year old hull for a while, this thread will be of interest, particularly this summary below from post #4:


"Moisture high, no bubbles, intend to keep boat for more than a couple of years - CopperCoat.
Moisture high, no bubbles, intend to sell soon - antifoul and enjoy sailing till she sells.
Moisture high, some bubbles, intend to keep boat - local repair and coppercoat.
Moisture high, extensive bubbles, intend to keep boat - full repair and coppercoat.
Moisture high, Bubbles and intend to sell boat soon - sell it now."

(substitute epoxy for coppercoat(which is an epoxy))...

Don't know how much it would cost to epoxy coat but have you/would you consider coppercoat?
 
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Lazy Kipper said:
The antifoul is being slurry blasted off in a couple of weeks so before priming the hull we have the opportunity to epoxy coat it - but should we?

What are your opinions? And if it really is a good idea what's the likely quantity needed for a 32ft waterline long keeler?

Thanks. Simon
Click to expand...

Hi Simon

If you are going to the expense of having the hull blasted then you have to be nuts not to have it epoxy coated after.

I used 5 coats of Gelshield 200 , then 1 x primocon primer, then 2 x Micron Extra, but we have recently found that Penguard HB epoxy primer is 'half the cost' and 'technically just as good' and we are doing two other CW 's with it this winter.

http://www.paintmarine.co.uk/penguard-hb-epoxy-primer-5ltr-46-p.asp

Just lifted 'out' after over two years 'in' and pleased with results. below is after just jet washing hull off.

Note: Do not epoxy the skeg (any steel),use 5 x primocon then 2 x antifoul.

If you want more advice drop a line.

Mike

DSCN4499.jpg

aft19122012.jpg
 
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Thanks Mike - it is an ideal opportunity but I was wondering about that whole business of locking in whatever moisture the hull has - or is 'drying out' a myth?
 
Where is the boat located? my recollection is that epoxy needs a reasonable ambient temperature to cure, and that does not sound like January unless the boat is under cover. Note it is only a recollection - suggest you check the product literature
 
RivalRedwing said:
Where is the boat located? my recollection is that epoxy needs a reasonable ambient temperature to cure, and that does not sound like January unless the boat is under cover. Note it is only a recollection - suggest you check the product literature
Click to expand...

East Coast - yes I'd have to wait until the weather warms up.
 
Gelshield has a minimum temperature requirement of 5deg C. It is possible to work fast as the product dries quickly. We did our five coats of Gelshield and two of Seajet over one Easter weekend.
 
Lazy Kipper said:
Thanks Mike - it is an ideal opportunity but I was wondering about that whole business of locking in whatever moisture the hull has - or is 'drying out' a myth?
Click to expand...

Hi Simon

The twp pack epoxy paint can says you need 5 deg C min, BUT, what is forgotten is the night tempreture, I would get your blasting done and let the hull dry out until spring and wait for 5 deg C at night min with say 10 C in the day.

Before you start applying epoxy however clean the hull down with thinners and then jet wash clean and allow to dry, DO NOT mix all the epoxy two pack all at once, mix only enough that you can put on in say 20 minutes.

Also after each mix let it stand for 5 minutes with the occatioanal stir, this gets rid of any trapped air bubbles in the coating.

Have a read here from the CWOG site that might also be of some help
http://f1.grp.yahoofs.com/v1/YD3kUG...chnical Information/Removing Old Antifoul.pdf


Mike
 
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Mine was blast cleaned by the previous owner (£475) in October 2011 after the boat had been out for a while only to get years of anti-foul off and then Gel Shielded with 2-3 coats in March once the hull had dried. Once in my possession I then put on another 2-3 coats this September just for extra protection. The boat didn't go in the water in the interim!

Get the different colours of Gelshield, usually grey/green, so that you can see where you have been for subsequent coats - easy stuff to use and quick with a small roller. I mixed 2.5 litres altogether no probs or bubbles, as always make sure you get a quality roller that won't leave bits or break up - it can ruin the job and all that preparation!

Kind of wished I had used Coppercoat now but many at the time said not to! Not sure how good it would be for keeping in over two seasons and it needs abrading/cleaning anyway, certainly doesn't stop the worms etc by going what you see in the yards this time of year.
 
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