What roller/brush for anti fouling?

Rivers & creeks

Rivers & creeks

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The hull is back to bare gelcoat (£300 for the slurry blasting - I was impressed!), we've lightly sanded and have to fill and fair some dings and then apply primer and antifoul. To be honest in the past we've just slapped it on but we've got the chance to do it properly this time! The primer is Flag metallic all substrate primer followed by 20L of vin de Seajet or something. What are the tips for putting it on because I've never used primer before - sheepskin or foam rollers? Roller or brush? Gaps between the coats? How many coats? Best weather conditions for applying? How thick for the primer coat?

Thanks. Simon
 
some foam rollers break down due to the adhesive used to affix the foam to the mandrill
Mohair will be ok or short hair roller for emulsion
i use a 7" roller on a pole

Lazy Kipper said:
The hull is back to bare gelcoat (£300 for the slurry blasting - I was impressed!), we've lightly sanded and have to fill and fair some dings and then apply primer and antifoul. To be honest in the past we've just slapped it on but we've got the chance to do it properly this time! The primer is Flag metallic all substrate primer followed by 20L of vin de Seajet or something. What are the tips for putting it on because I've never used primer before - sheepskin or foam rollers? Roller or brush? Gaps between the coats? How many coats? Best weather conditions for applying? How thick for the primer coat?

Thanks. Simon
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I think foam gives best finish but in some a/f e.g. Jotun they dissolve (yes even the ones marked solvent resistant).
Next best is very short pile/mohair.
Long pile leaves it textured! Maybe my technique.
Can't comment on Flag primer. I used Jotun Vinyguard.
 
I've always used a small ("radiator") roller, 4" length or thereabouts, with a short pile.

I've noticed that recently the rollers for these seem to have reduced in diameter considerably, they now seem like toys compared to a few years ago.
Older ones were about 50mm diameter, now they are more like 25mm.
The earlier type were much better, a good compromise between manouevrability and coverage, and one roller would just about last a coat before it was worn out.
Haven't used the smaller type yet, am still looking to see if I can get any of the old type, but I've only seen long pile versions in the new type so far.
 
Do not use hair based rollers they tend to leave hairs sticking out which attracts growth, use foam ones made for gloss paint.
 
Lazy Kipper said:
The hull is back to bare gelcoat (£300 for the slurry blasting - I was impressed!), we've lightly sanded and have to fill and fair some dings and then apply primer and antifoul. To be honest in the past we've just slapped it on but we've got the chance to do it properly this time! The primer is Flag metallic all substrate primer followed by 20L of vin de Seajet or something. What are the tips for putting it on because I've never used primer before - sheepskin or foam rollers? Roller or brush? Gaps between the coats? How many coats? Best weather conditions for applying? How thick for the primer coat?

Thanks. Simon
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Hi Simon

You got to be nuts to have had the hull blasted and you are just going to put a single pack primer and antifoul on.

You need to protect the hull now and apply a two pack epoxy (usually 4/5 coats of it), THEN apply the primer THEN apply the antifoul.

I did mine back in 2010 as I stay 'in' for two years at a time and applied the recommended 5 coats of International Gelshield 200 available in differant colours(grey/green), so you do not miss any when recoating, then one coat Primocon primer then 2 x International Micron Extra.

However we are re coating another CW next to me and this time we are using Jotun Penguard HB which is MUCH cheaper and you get more and it's just as good http://www.smlmarinepaints.co.uk/primers/two-pack/penguard-hb, after applying 4 coats of the Penguard HB we will prime with 1 x Jotun Vinyguard silvergrey88 primer then 2 x Jotun Seaqueen antifoul.

I always use the 100mm long foam rollers, you can get a pack of ten from B & Q for under £10, I also see no mention of cleaning down, before starting anything clean with thinners, we use International Paints No 7 thinners.

However do not apply anything until the tempreture is above 8 deg C min in the day and 5 deg C min in the night

No it's not cheap but you are protecting a large investment!

Drop me a line if you need any more info

Happy painting

Mike
 
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Hi Mike, thanks as ever for a thoughtful response. Lazy Kipper hasn't ever been epoxy coated and there's not a trace of osmosis; may as well put some epoxy on but I have heard of issues where older boats like mine have been epoxy coated and then very quickly started to get osmosis as they can't dry out in the traditional sense each winter, it locks the moisture in - but as the Kipper has been out since November and was out for two of the last three years surely the hull is dry enough now??? Going back in in four weeks so lots to get done.
 
Hello Lazy Kipper,

If it was me, I would spend a bit extra on the AF and go for the Coppercoat...

Just a thought as you have all the preparatory work done.

If you go for Coppercoat, get the CD from the supplier and DILUTE to the MAX recommended by the manufacturer. Apply one more thin coat than recommended if necessary. You wont regret it!

GL
 
Makes sense in some ways but even going for the Penguard, the standard primer then good quality antifouling costs me £380 all in and lasts 2 to 3 years, subsequent coats of antifouling costs £80. The quote for Coppercoat was £1200 DIY and if I get the application wrong that's £1200 down the drain plus a nightmare to get right again.
 
Just finished mine used 4 inch foam rollers bought two of these multi pack of 10 one from B&Q the other from Wickes. Now I don’t know why but the Wickes rollers lasted a good deal longer. The B&Q ones did disintegrate with pieces of foam coming off onto the hull surface. You do need to change rollers frequently.
 
Caer Urfa said:
we are re coating another CW next to me and this time we are using Jotun Penguard HB which is MUCH cheaper and you get more and it's just as good http://www.smlmarinepaints.co.uk/primers/two-pack/penguard-hb, after applying 4 coats of the Penguard HB we will prime with 1 x Jotun Vinyguard silvergrey88 primer then 2 x Jotun Seaqueen antifoul.
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What's the overcoating time with the Penguard at this time of year? Do you get more than one coat done in a day?
 
I've found that B & Q simulated mohair do the job well with a brush for the tricky bits. Don't use foam rollers as the solvents in the AF will disolve them before long. Use the largest size roller you can handle without excessive strain - you'll finish much quicker than if you pootle around with 4" radiator rollers. I find an 8" just about right. (Oooh Matron)
Put your overalls and hat on before you get paint splashes on you.
Drying time varies but probably by the time you've done one coat, the place where you started will be dry enough to re-coat.
Like someone has already said, I'd take the opportunity to put some epoxy on your nice smooth bottom.
 
ghostlymoron said:
I've found that B & Q simulated mohair do the job well with a brush for the tricky bits. Don't use foam rollers as the solvents in the AF will disolve them before long. Use the largest size roller you can handle without excessive strain - you'll finish much quicker than if you pootle around with 4" radiator rollers. I find an 8" just about right. (Oooh Matron)
Put your overalls and hat on before you get paint splashes on you.
Drying time varies but probably by the time you've done one coat, the place where you started will be dry enough to re-coat.
Like someone has already said, I'd take the opportunity to put some epoxy on your nice smooth bottom.
Click to expand...
I might get through 2-3 4 inch foam rollers on 34 ft boat, so I dont think they fall apart much. Wickes gloss was good;cheapo ones last seconds.
As regards the size of roller, I suspect the choice depends on temperature. When warm , maybe a larger one is ok, but with thick heavy a/foul (when cold) you'll need to be eating alot of spinach to use a larger roller.
 
Lazy Kipper said:
What's the overcoating time with the Penguard at this time of year? Do you get more than one coat done in a day?
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Penguard is about 55% solids i.e. 45% solvent.
Gelshield 200 is about 45% solids i.e. 55% solvent.
At this time of year you must give plenty of solvent drying time at least a day between coats.
Also you need to make sure the temp is enough for the epoxy to react at all. You can get a low temp additive for the Penguard. It's pushing it to the limit. I would take advice from Malcolm at SML, he's very helpful, phone him.
The Vinyguard primer and a/f are not a problem not being 2 part.
 
Lazy Kipper said:
What's the overcoating time with the Penguard at this time of year? Do you get more than one coat done in a day?
Click to expand...

The answer is at this time of the year is you don't apply it! (unless the tempretures increase in the next weeks)

They say it can be applied at about 8 deg C, BUT, what most people forget is the night tempreture, On the CW next to me we will not apply the Penguard HB until we have about at least 10 deg in the day and min 5 deg C in the night.

Coating times we work on is Min 24 hrs at min 10 deg C.

See here for coating times and application data http://www.smlmarinepaints.co.uk/fil...rd_HB_data.pdf

Also I see a comment about applying the Vinyguard primer, SML will tell you that it is very susceptible to moisture at the application stage, any signs of damp on the hull will possibly cause 'bubbles' when it dries.

We all want to get back 'in', but hurrying the job could prove expensive plus you have just wasted a lot of your time.

Mike
 
Caer Urfa said:
Also I see a comment about applying the Vinyguard primer, SML will tell you that it is very susceptible to moisture at the application stage, any signs of damp on the hull will possibly cause 'bubbles' when it dries.
Click to expand...

Yes I just meant low temp is not a problem but agree needs to be dry and also low humidity so you don't get condensation on it from evaporation.
 
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