Anti-foul removal help/ ideas needed

[freespirit3]

Hello folks

I want to remove the anti foul on our rib, this had been painted onto our hull before we bought it and follows the water line, I managed to remove it last year from the transom as i fitted a new elephants trunk, now my next job is to remove it from the hull port and starboard.

I have been using the Interstrip A/F as it suggests but it doesn't seem to go along way and seems to transfer around the hull and make a mess.

It suggests you use thinners number 3 ?? to clean off any residue, does anyone know if this product is the same as normal thinners, I have a 5L of tolulene from when I have done tube repairs in the past, can I use this to clean off the anti foul residue or will it do damage to the grp.

Any ideas on a better process, we don't plan to add new antifoul, we plan to polish the hull back to original as the boat is never left in the water.

I did look at soda blasting but was worried that that would send the hull flat and matt, I have been applying the interstrip as it suggests with a brush onto the anti foul on the hull dry then leaving it to soak for ten minutes and then scraping it off with a plastic scraper, should I also use a pressure washer.

Any ideas on a better process and thanks for reading

[Iron Dials]

I used Interstrip last year. Rotten and slow but it worked.

Dont leave it for 10 mins, if you let it dry out its dreadful.
Maybe you've tried this already but I found that working it into an area and then removing while it was still a paste was way better.
I then used a cloth to wipe off the final layer to leave a clean hull.

Hope this helps.

[gtflash]

I used about 10 tns of interstrip and only got about half off. It was only really successful on flat surfaces where I could use a decent Stanley blade.

Promised ,yield next time I'd use ARC who come and blast hull. It would have cost less than interstrip.

[Iron Dials]

I forgot to mention that i used cheap plastic windscreen scrapers so that I wouldn't mark the hull. 3 in total.

When I got my boat all of the hull had been anti-fouled, looked awful.
1 can got almost all of above waterline area cleared. It needs to be scraped before it dries.

[Brian]

Hows about using shot-blasting?
Would this work?

[gtflash]

Originally Posted by Brian

Hows about using shot-blasting?
Would this work?

I tied some sort of blaster too. It was an attachment for my compressor with some sort of soft ish blasting medium. It did take anti foul off but a,so some gel. Left a great texture for re painting but No good if you wanted to buff it up after to look like new. I ant remember what the shot blast was though

[rnwright1969]

One of the jobs which I finally got round to in my 'well used' 5.4 sea-rider was the removal of 'many' layers of anti-foul. After various checks and enquiries I went with a company called 'enviroblasting.co.uk'.
They are based near Hexham and basically slurry spray the boat with a glass/water mix which is variable in the quantity and 'roughness' of the glass and the pressure at which it's applied, after fifteen minutes or so 'upping' the abrasiveness of the mix the guy did the entire hull in another half hour.
Top job and a nice finish too!

[freespirit3]

Thanks for all of your support and advice, have managed to get one full side done and now half way along the other. Only took two days grrrrrr..........

Decided on the inter strip AF, Iron dials comments work, brush it on and then scrape the residue off and if it is still wet wipe off, in my case the previous owner had someone re paint the hull with antifoul, however they had painted over the barnacles, this took more time to remove!

I want to remove all residue of the old blue on the white hull, what product would you recommend do get it clean and fresh ready to polish? can i use thinners?

Looks a 100 times better

[diver 1]

I had the same problem. I used Owatrol Marine Strip from Force 4. After reading lots of reviews and tips and trying for a while as you said I found the following worked better than the instructions.

Paint on thickly about 300 x 300 mm at a time then quickly cut a bit of cling film the same size and cover the wet gel. Keep repeating until the whole hull is covered 100% in gel overlaid with clingfilm. The clingfilm serves to prevent the gel from drying out.

I then left the boat for 12 hours 'soaking' in this gel.

Set up a high powered power washer so its all ready to go and put waterpoof suit, wellies, gloves and eye protection on (not being a namby but this stuff burns a bit especially if it goes in your eyes!)

Quickly remove all bits of cling film

Powerwash hull.

I found this method made it much easier to remove the anti foul

I still had to use fine wet and dry in some areas to remove residue.

Polish hull afterwards to restore GRP finish.

[freespirit3]

These are pictures of before and after

[freespirit3]

Just the blue residue to remove, is it best to wet and dry or use thinners to fully clean it off

[Iron Dials]

Glad to see it worked for you.
I re-visited the residue, with even more brushed Interstrip and a cloth.
Eventually it all came off.

[A1an]

Ive got the same issue at the moment. The soda blasted is booked for last week in March. Cant be arsed with the hassle.

[freespirit3]

I have to say I have been really pleased with how the product worked and no damage to the hull.

Could pretty much polish it up, I heard of a case of a boat that was soda blasted and it took a bodyshop guy 3 days to polish the boat and even then it was mediocre, worth checking it out first.

[Orwell boy]

I did the job on a 18ft sports boat once ,used a product called strippit from devon /cornwall if I remember rightly , that and a hot pressure washer ,worked fantastic , only trouble was the boat was antifouled by the boatyard from first delivery and they had roughed the surface with a disc sander to ensure good adhesion , I was starting with 200 grit ,then 500 then 1000 and 2000 . followed by g6 then g3 , I spent a whole winter at it , still got a bucket somewhere with every kind of sponge applicator and buffing wheel you could imagine not to mention remains of industrial packs of p1000 and p2000 , must confess I was well happy with the results which you could never tell it had been antifouled , I hope I never need that bucket again ha ha

[freespirit3]

Finally got it all off, all in all used 4.5 litres of the Interstrip and many hours of swearing and stiff necks from lying underneath it, all I need to do now is get a polishing mop and some polish and get it back up to shine, hoping all of the blue that you can see will polish out.

As said before would have been quicker if the previous people had removed the barnacles first before anti fouling over the top.

Hoping to see some small improvement in speed and fuel consumption, the hull was really rough and bumpy before, now at least it is smooth

[willk]

That's a really nice job - well done, I know what's involved

You will absolutely notice an improvement in speed. I would add the additional rider that weights play a big difference in top speed too. I sanded and carefully repainted AF on my previous RIB. At the same time I removed all her additional equipment prior to sale. That sort of gear would include tools, spares, many warps and spare anchor etc. It was quite a pile of stuff on the ground! I got about an extra 2 knots on a heavy 6.5m boat.

[willk]

Originally Posted by freespirit3

As said before would have been quicker if the previous people had removed the barnacles first before anti fouling over the top.

I see you're a glass half empty kinda guy...

Flip side is, had they given a damn, they would have also keyed the gelcoat with some 80 grit before painting - so maybe you lucked out!

[freespirit3]

Agreed, looks like they just gently buffed the hull prior to the anti-foul application, I was expecting worse but as I found the barnacles I started to get a warm feeling that the hull was in good fettle underneath and that the hull hadn't been keyed in as it could have been, as you can see from the pictures the hull is in good condition for what is a 2004 boat, the tube tapes also.