Anti-fouling removal started.

[brett62]

I have had on my long list of items to complete on the boat before I put it back in the water THE REMOVAL OF ANTI FOUL.

I have been putting it off for some time but now I am nearly completed the trailer I have to get to work. I did a lot of research on what would be the easiest way to remove from the bottom as sanding upside down was not something I was wanting to do. Guess what, that's what I am doing. I looked at soda blasting and was nearly ready to go that way until a friend had his 10m cat blasted and some of the glass lifted and cost him a considerable amount to repair before he could re-anti foul his boat.


I tried the stripper idea and had some success with a product called Peel away which removed the anti fouling with no problem with a high pressure blaster. The undercoat was a different story and didn't even look like it would ever remove the undercoat in a million years. So I tried a few different types of strippers to see what would get it off and one I found removed the undercoat and also the gelcoat which was not good. Now I have a repair also but I only tried a small area so no big deal.


So out with the compressor and the sander for some fun times. I am doing the sanding with wet & dry so I don't have dust and crap all over the place. I start with 80 grit to get the bulk off and then 240 grit and then 400 grit. By this stage your back to the gelcoat and then starts the process of getting the gelcoat back to a nice finish which I use 1200 grit and then cut and buff back. I have only cut and buff a small area to see how it comes up and very happy with the finish. I am lucky that the boat had only seen one coat of anti-foul and whoever sprayed on didn't sand the gelcoat back before they placed the undercoat. I have gone back to glass on a couple of the strakes towards the bow which I will fix with gelcoat.


It would be something that you do once and I have read many post on here about the fun people have had with the removal. When I sit back and look at what I have done so far I am happy to see it gone. The only problem is looking at what I still have to remove!!!!!!!!!!!!!!!!!!!

For those of you that have had the pleasure of doing the same as me did you find a easier way or am I dreaming and just need to harden up and get on with it.

Some before and after shots.

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[Snapperscott]

Yeah I've done the same but I am stuck now because the areas left the trailer gets in the way. I like the idea of making a cradle but how did you get the boat off the trailer onto the cradle?

[brett62]

Yeah I've done the same but I am stuck now because the areas left the trailer gets in the way. I like the idea of making a cradle but how did you get the boat off the trailer onto the cradle?

Mate I just ran chain from the transom cleats and anchored to a car then you just jack up the keel at the transom to take some of the weight and have the tow vehicle slowly move the trailer forward about 2 feet and then slip 2 of the frames under. I then use tapered timber wedges on the first frame under the transom and then move the trailer forward again and position the 2nd frame and wedge in place. I then move the jack up towards the bow under the keel and jack the bow up adjusting the wedges on the second frame as I go up. By this time you will have no weight on the trailer and can just drive it away. I then place the 3rd frame and wedge in place. I would not even attempt to try and sand on a trailer as that would be a pain in the ass. As I sand and buff the hull I will jack up and move the frames forward/aft so I can get some room.

I will be keeping the cradles as when the time comes to work on the trailer it only takes about 2 hours to get it off the trailer and onto the cradle and putting the boat back on is quicker.

[fisho64]

I have done it.
Oven cleaner, the caustic one not the non caustic.
PM me if you want more detail?

[Fed]

I got the guys at work to do mine dry with paint scrapers.
Ground the sharp corners off the scrapers and only copped 1 or 2 very small marks.
Simply shifted it back on the trailer to get the hidden bits.
It's quite possible mine wasn't applied very well but it was very old & thick, sanding would have been a nightmare.

[brett62]

I got the guys at work to do mine dry with paint scrapers.
Ground the sharp corners off the scrapers and only copped 1 or 2 very small marks.
Simply shifted it back on the trailer to get the hidden bits.
It's quite possible mine wasn't applied very well but it was very old & thick, sanding would have been a nightmare.

Yep I am not that lucky as the undercoat is well and truly attached to the gelcoat. The actual anti foul coat is easy to remove with the Peel Away. The older the easier it is to remove I have been told. The system on my boat is only 12 months old so is still attached pretty well.

[stockhorse]

"I looked at soda blasting and was nearly ready to go that way until a friend had his 10m cat blasted and some of the glass lifted and cost him a considerable amount to repair before he could re-anti foul his boat."

Could you expand on this at all ?

[fisho64]

soda blasting often leaves pitting in the gelcoat.
And if the operator hasnt done it on glass before, dont be the guineapig!

[brett62]

"I looked at soda blasting and was nearly ready to go that way until a friend had his 10m cat blasted and some of the glass lifted and cost him a considerable amount to repair before he could re-anti foul his boat."

Could you expand on this at all ?

From what he told me it seems that some of the glass layers separated from the blasting and in some areas it exposed bubbling. He also had pitting in other areas that he also had to seal. The boat had many layers of anti foul over each other which would have been a real pig to remove. I don't know if the blasting caused the problem or it just exposed the defects. I have heard of others using the soda blasting method and had no problems. I think you would still need to cut and buff the gelcoat after blasting if you wanted a shiny smooth finish. My boat is only 7m and decided sanding off would be better for me.

[brett62]

Couple of questions with regards the best way to do some repairs on the gelcoat where I have sanded through to the glass. I have also found a section on the keel at the bow where I think would have been damaged from previous owner hitting the first roller when he was driving the boat on the trailer. Has a little impression in the area. I am sure I will find other repairs as I remove the anti fouling or sand down to far on the strakes. I have completed the first 2.5m on both sides and the plan is to complete any repairs and buff before I move the stands and continue with the next section.

I want to do a good job so the repairs are not noticeable and any advice on what materials and equipment to achieve this will help. Colour matching advice will help also.

[brett62]

I am about 75% completed with the removal now at last and should have it all off next work break. I will then be repairing a few areas and buffing up. I have purchased gel coat and some filling materials for the repairs. I was thinking of spraying the areas I am repairing with a standard type spray gun as they are not big areas. Would I be better using flow coat as it's thinner? also where I have gone back to the glass (but not into the glass) would I need to sand down further or just feather back when spraying over a larger area.

Is tinting the gel coat a good idea as I would like it to look the same as the rest of the boat or will it be to hard. Someone told me that the new gel coat will fade in a short time to the same colour. Not sure if that is correct or not.

[Moejoes]

I am about 75% completed with the removal now at last and should have it all off next work break. I will then be repairing a few areas and buffing up. I have purchased gel coat and some filling materials for the repairs. I was thinking of spraying the areas I am repairing with a standard type spray gun as they are not big areas. Would I be better using flow coat as it's thinner? also where I have gone back to the glass (but not into the glass) would I need to sand down further or just feather back when spraying over a larger area.

Is tinting the gel coat a good idea as I would like it to look the same as the rest of the boat or will it be to hard. Someone told me that the new gel coat will fade in a short time to the same colour. Not sure if that is correct or not.

Hi Brett,
Glad it's you, been there done that and hated every minute of removing that antifoul on one of my last boats.
She's looking good tho.
Your fuel economy should be better as well.
Cheers Rob.

[brett62]

Hi Brett,
Glad it's you, been there done that and hated every minute of removing that antifoul on one of my last boats.
She's looking good tho.
Your fuel economy should be better as well.
Cheers Rob.

Yep not something I will ever do again. Worst pain in the ass I have had to do on a boat yet. I looked at it for so long and dicked around every now and then with it. I finally finished the trailer so I had to take some action and get moving so I could get it on the trailer. Certainly should slide through the water a little easier and only good thinks can come from that. I am glad I did remove as I have found a few spots that they just painted over with the anti foul that should have been repaired first. On the whole the hull was pretty good and only cosmetic type damage from beaching and trailer mishaps. They should have still fixed them instead of sealing off with paint.

[Moejoes]

I was the same.
I'd chip away at it every now and then.
At least you know exactly what's hidden under it now.
Looks good in the pics.

[Snapperscott]

Times three still only 3/4 of the way through

[brett62]

Times three still only 3/4 of the way through

Mate now you are member of the silly people that have done this. It's a club I never wanted to join LOL.

[toddo1]

Anyone tried the blasting with glass and water, heard there's 2 blokes that do it and heard good things! No heat or dust because of the water but still have the benefit of knocking it off quick

[brett62]

Before and after photos. Only have the stern to complete which will be nice and easy after working upside down for days. I completed any gelcoat repairs which was a first for me. I ended up going down to bunnings and getting some colour cards and then asked them for the pigment and mixed it up. I sprayed on with a standard gun with no problems. Well I should say I did stuff up one mix as I mixed with 2% hardener on a hot day and the gelcoat went off in 5 mins and it was a mad rush to clean the gun before it went hard. Never going to do it again ever but I am happy I did as the results are good. I did sand with wet and dry all the way and used 200 disc and then cut it back with P200 and P500 cutting compound. It will slide through the water much better than before. The anti foul was I think put on with a roller and was very rough. I was lucky it had only had the one application and they did not sand the bottom before applying.

I read a few post on here before starting this and can now confirm that all the negative post from people who have done this are correct and if you are thinking of doing this I would suggest you take it some where and pick it up all completed. It really is a pain in the ass. http://www.ausfish.com.au/vforum/images/icons/icon7.png

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