New to forum and bottom paint question

[GK1]

Hello, I just bought my first aluminum boat, and am new to the forum. It's a custom build from a guy in interior BC in 2005. It's a pretty unique hull design as far as I can tell, and from the small amount I have used it so far it cuts through the water pretty nicely and is pretty stable to fish out of. I bought it off the first owner and he had never kept it in saltwater overnight, so it has no bottom paint. I'll be keeping it in the water most the time year round so want to have a proper bottom paint job done pretty soon. I have looked through some of the previous threads and there is some great info on here, I think I know generally what to watch out for and that I don't want to try it myself without the proper shop and equipment.

I am wondering if anyone has any advice on good options for having this done in the Victoria/Sooke BC area? Any one want to venture a ballpark guess at what I might have to pay?

One other question, the hull (unfortunately I expect) was lacquered originally, so I suspect this will have to be removed completely before the bottom gets epoxied and painted? I'm thinking maybe I should try to remove this myself to help with cost. I guess I would need to sand down to bare aluminum? I'm wondering if a heat gun and scraper would do it as well. Any advice/comment on removing the lacquer? The lacquer is bubbling in spots, in the attached pictures, it looks like corrosion in spots but that is just the lacquer bubbling as far as I can tell.
Thanks, looking forward to learning a lot from this forum.

[Chaps]

Sleek looking rig, welcome to the site. There are a few members here that live in that area that can likely advise you on where you can take your boat for bottom painting. Ideally you want to have the bottom sandblasted, then epoxy primer then anti-foul paint. Due to Canadian enviro regs the paint choices you have available up there are very limited. If sandblasting is not available a thorough machine sanding of the hull with coarse abrasive is your next best choice. Obviously either prep method will quickly remove any coatings that are on the bottom so don't waste your time attempting to remove them prior to the job. Good luck with it, looks like a fun boat.

[kmorin]

GK1, welcome to the foremost forum on fantastic, fun and functional welded aluminum boats.

Nice design, the very raked bow stem combine with the narrow sections forward seem to mean she'd run well into a head chop and remain mostly dry without pulling any 'veers' of the helm we see in some designs with more spoon forward.

Not talking just about bottom paint, here, but simply a few reminders (these remarks are else where, using the search function here can be as useful as a decade of rumors and misconceptions that get posted and not examined on some other sites.) about coating aluminum.

Chaps did not say, but will probably agree (?) that any paint film on aluminum has to ways to bond, the best is to have both- not just one. First, is mechanical that is an 'anchor pattern' resulting from high speed particles (very closely tune in size and velocity) cutting and forming the surface into the anchor pattern. Think micro hook and loop for plastic paint films to 'grab' and hold onto. Sand blasting is the best to provide this but like the best in most cases; it ain't easy - so it's not free unless you work somewhere they blast all the time and have some stroke.

Next way to bond to aluminum is chemical and that needs a quickie review- too. Chemical bonding to aluminum oxide, the naturally forming 0.002-0.003 thickness film is weak at this time. Don't get me wrong about the oxide-to-aluminum bond... that's a good bond but soft film (takes lots of heat to melt but the material is soft) and bonding to AlOx is a "pain in the stern". (note anytime anyone in the boating world says pain in the stern add three zeroes, 1$ becomes $1,000.00, to the imagined cost- immediately.)

So etching or acid coating to remove the aluminum oxide film is good practice and then a replacement oxide with a much tougher chemical bond is often used... . various oxides (chrome is common) can be formed and then an epoxy primer that bonds to the new non-aluminum oxide is the best practice for painting aluminum above or below the waterline.

But as I said, and think everyone will agree, the best chance of paint sticking to aluminum is to use both methods... that is why, in regard bottom paint Chaps told you the best you could do is a blasted anchor pattern and the next best is a circular buffed in roughness. (Quick note: Michelangelo Grinding is not for the faint of heart and should be avoided for anyone who's not used a grinder before)

Now to the topsides. Its looks in some places but not in others.... (?) that the mill scale was removed from the topsides? The uneven coloration seems to have patterns but I can't tell from the images? If a lacquer/Nayalac (sp?) /Shark hide type of clear coating was used to attempt to retain the boat's coloration then.... #1 that usually promotes crevice corrosion once the film is breached. #2 If the film's UV break down (not sure of product but they all have a life) were to allow the cracking and water to get behind the film, then re-coating is about the only cure. #3 A simple acid rinse once or twice a year is a valid alternative to coating but the look of the look will not be that of shiny film coated metal.

To remove all films from boats there are paint removing chemicals that will solvent and lift the purely chemical only bond to them metal. They could strip your boat in a day and once rinsed it would be ready for acid etching, and then re-coating in a day's work.

My general take on all clear coat products is they are short sighted. They're for a look that gets damaged fairly quickly, I prefer the 'real thing' and just to see the metal, but here in Alaska the overall looks factor is low compared to other areas of the country so I'm not a very good reference in that department.

Again, Welcome to AAB.com Forum, we always like to hear what you've decided and more importantly I'd say we'd like to understand why you made a given decision? Either way, looks like a nice ride and I hope my remarks are helpful in some regard in your decision tree? IT should be noted that I am the site gnat-zee in regard mill scale removal with acid or buffers and harp endless about that aspect of welded metal boats- so a grain or block of salt is well served with my remarks.

Cheers,
Kevin Morin
Kenai, AK

[GK1]

Wow that is a lot of information to process, thanks for that. Although I need to read through that 5 or 6 more times...I did call several places in the area and I got the best feeling from blackline marine in sydney. To make long story short, several places I called suggested between 2 and 5 coats of inter protect then 2 to 3 coats of trilux 2 (some said trilux 3?). Blackwater were the only ones to suggest that intercoat epoxy needed to be applied soon after sanding/preparing the bottom otherwise oxidation would require re-preping the hull, so any work I did before hand might help a bit but maybe not worth it in the long run like you suggested Chaps. They were the only ones to quote three coats of trilux 2 over 5 coats of inter protect, with the first coat blue and the last 2 coats black to watch for wear on the bottom paint. They said they would mechanically sand and if it seemed to require it (the lacquer) they have sandblasting capabilities there.

If anyone has any words for or against Blackline I'd be interested to hear? Or still open to other suggestions.

I appreciate your thorough reply kmorin. From what I am gathering so far the best I am going to get is a good mechanical bond from any of the painting joints I spoke with today, no one mentioned chemical bonding (nor acid etching for that matter). As for the clear coat, I don't know what it is or whether the mill scale was removed. I'm not even entirely sure i know what mill scale is but I googled it and found one of your previous answers on this forum so I think I get it. I could try to contact the builder if it was important enough? There is indeed a bit of different coloration, mostly on the stern, where the change in colour seems to be under the unbreached clear coat there - some of the metal has a bit more of a yellow tinge. Elsewhere here are spots where the clear coat is breached and bubbling, and there is actually a worm like pattern in some of those spots? I just closed my truck door on my phone so it is now mangled, otherwise I would post a close up. I have no interest in a clear coat to preserve a certain look, I would prefer a bare aluminium hull or whatever will last the longest and require the least maintenance (I might fit in in AK). I am not sure if I understand you correctly, is there a solvent product that will remove the clear coat? I'd consider getting it all off the hull once and for all if it is likely to cause problems in the future as I don't want to maintain it and worry it might cause problems unmaintained? I was hoping to reduce maintenance by buying an aluminum boat!

Thanks again

[Chaps]

It sounds like the Blackline folks know how to do the job correctly which is a good start, yes it is recommended that the first coat of epoxy goes on quickly after the aluminum is abraded. They might have also mentioned (should have anyway) that the first coat of bottom paint needs to be applied to the last coat of epoxy while the epoxy still has a slight tackiness to it. Five coats of epoxy is a bit of an overkill if they are applying it heavily, that amount is more typical on a glass boat that needs blister protection but take it if included. If they have sandblast capability I'd ask what the upcharge would be to prep the hull that way instead of the power sanding. Power sanding will typically yield good results on the broad flat areas of the hull but any tight spots on the transom, bottom strakes, welds, other sharp bends, etc. usually don't get the attention they require from a disc sand operator. To bad Trilux is your only paint choice, that Canadian approved version doesn't work very well so expect to recoat frequently.

If you want to tackle the clear coat (if it is Sharkhide or similar) try a liberal application of lacquer thinner via spray gun, keep the surface wet for several minutes to allow it to work then wipe off with rags.

[Shark Bait]

GK1

I agree with Chaps assessment of Canadian Trilux. When I had my boat built by Daigle Welding in Campbell River BC I had bottom paint put on. Steve Daigle has been building aluminum boats for a long time so I did not do any research on the bottom paint. If I had it to do over again I don't think I would waste the time and money having bottom paint put on in Canada, mostly because your environmental regulations do no allow for an effective bottom paint.

My boat was delivered with the Canadian approved Trilux and is used in south central Alaska. At the end of the first season, about 5 months in salt water, I had a ton of slime on the bottom but no hard growth. It was cleaned before it was stored for the winter. The slime always came back. I finally replaced it with a Pettitt product, don't have time to look up the exact produce right now, but I selected one with good anti-slime properties as hard grown is not much of a problem in our cold waters. The Pettitt produce had dramatically reduced the slime build up each season.

I would recommend doing a lot of research into what bottom paint is available and legal in Canada before going to the work and expensive of putting it on - it may not be worth it.

[Gypseas]

Took mine to Jenkins marine and so far pretty happy with workmanship and price. They have a set price per foot can't remember what it was but I walked out of there just shy of $2k lighter than when I walked in LOL
I did take it in based mainly on word of mouth from people I know all of which were also happy with the services provided.
cheers

[GK1]

Thanks Chaps, whoever I get to do it I'll ensure they know about putting the bottom paint on while the epoxy is still tacky.

Sharkbait, every place I have called so far has indicated they use trilux so I suspect there is not much for other paint options but I'll look into it as you suggest.

Interesting that you mentioned Jenkins Gypsies and glad to hear you are happy with the results. How long ago did you have it done there? I have a friend with a fibreglass boat that was just done at Jenkins, he is happy with it so far but it's only been half a year or so I think.

Jenkins were the lowest quote, by a fair amount actually, I think they said ~$1200 for a 21' boat. I was hesitant though because they said their quote was for only 2 coats of interproect and 2 coats of bottom paint. Everyone else said at least 3 coats of inter protect. I also got a quote on sandblasting from a nearby place in Sooke for ~$600 - I'm wondering if the best plan would be to go that route, and line it up so it gets blasted than goes straight to Jenkins, who I will ask for 3 coats of inter protect instead of 2. This would be convenient as I am in Sooke and given the prices quoted this would still cost about the same (or even less) as everywhere else although I'll have the benefit of sandblasting. Jenkins mentioned they pressure wash using some sort of sand infusion end on the pressure washer, but I'm not sure that will be enough to get rid of the lacquer properly.

Thanks for your input everyone, I will let you know what I do and how it goes...and how bad it dings my bank account.

[Chaps]

A pressure washer with a sand sucker nozzle on it can do a reasonably decent prep job if they have it dialed in and a good operator doing the blasting. They make a huge mess and waste a lot of blast media but that's their problem. On evaluating the number of coats of epoxy, its often a meaningless number because the quality of the job ultimately depends on how much epoxy finally ends up on the boat. Some shops will put on two heavy coats while others might claim to put on 5 coats but chances are they were thinned with reducer so its likely that final coating thickness at both shops is the same. Better to get a shop to commit to applying a specific amount of epoxy (1 gallon for instance) and let them decide how they want to apply it as far as number of coats. On paints you might check into the availability of a product called Flexdel Armor. Its made by the same people that make Aquaguard water based coatings which I believe are approved up there. The Armor is a solvent based non-copper bottom paint that I've started applying down here and so far its working pretty good. I have not found that waterbased bottom paints adhere very well to epoxy primers however so take that for what its worth if you start to consider any of those.

[GK1]

OK good to know thanks Chaps. I have written flexdel and asked if that paint is available in Canada.

[kmorin]

GK1, I'm not familiar with the relative regulatory agencies, your inspections North of the Border, or much detail involved. However.... reading the thread it strikes me that there could be a cost advantage to hauling the boat to the States side of the border, have the work done once with a longer expected life to the job, then going to home waters to use the boat?

If the products used North are very much shorter life expectancy than south, about the second re-coat I think the initial trip and higher performing 'southern product' regulatory climate may be more cost effective?

I have no idea if this is true I'm just reading the two or three back and forth exchanges and this thought came to me as a consideration I'd make. If I were knowingly putting on a less long life product, and knew I was going to need to do it regularly at a short interval, I'd conclude that the trip might pay for itself?

just speculating.

Cheers,
Kevin Morin
Kenai AK

[Shark Bait]

Good thoughts Kevin but in addition to longer life the US approved bottom paint yields much better performance. With the original Canadian approved bottom paint on my boat it was difficult to see any protection, especially with the build up of slime.

[Chaps]

GK1, I'm not familiar with the relative regulatory agencies, your inspections North of the Border, or much detail involved. However.... reading the thread it strikes me that there could be a cost advantage to hauling the boat to the States side of the border, have the work done once with a longer expected life to the job, then going to home waters to use the boat?

If the products used North are very much shorter life expectancy than south, about the second re-coat I think the initial trip and higher performing 'southern product' regulatory climate may be more cost effective?

I have no idea if this is true I'm just reading the two or three back and forth exchanges and this thought came to me as a consideration I'd make. If I were knowingly putting on a less long life product, and knew I was going to need to do it regularly at a short interval, I'd conclude that the trip might pay for itself?

just speculating.

Cheers,
Kevin Morin
Kenai AK

I have heard that Canadian Customs watches for its citizens bringing freshly painted boats into the country . . . and we thought we were living in a police state down here?

[kmorin]

Chaps, not a surprise I guess. Liberty and freedom are things of the past, I'll just stay in the trees and hope to avoid as much as possible...

Cheers,
Kevin Morin
Kenai, AK

[GK1]

Yes, with the government we have in place here now freedom and liberty are not a high priority (see the soon to be in place bill C-51). The rest of the world progresses and Canada regresses. I digress though this is about bottom paint. I thought of looking south of the border kmorin but think I'll stick it out here, I have some faint hope that our regulations are in place because there are some ecosystem benefits to the regulation of certain products....even though what we are left with apparently sucks.

[Chaps]

What part of the world is progressing? All we get down here is more and more regulation, I guess the lefty's call that "progressive"