Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 30-07-2021, 22:17   #1
Registered User

Join Date: Apr 2017
Location: Auckland, NZ
Boat: Cavalier 39 Mk1
Posts: 63
Removing old anti-foul bottom paint. Thread?

I can't find the thread I'm looking for, it must be here somewhere...

What's the quickest way of removing old, thick, patchy bottom paint? I have the boat at home and there are no issues with dust or noise, etc. I've tried an abrasive flexible disc on a grinder, but this seems to be too uneven and before you know where you are you are through the gelcoat. I've tried a belt sander, but this didn't seem very effective on the old antifoul, but very effective on the gelcoat again, unfortunately. I've tried a wood chisel by hand, but this will take forever and will still need sanding afterwards. I've already waterblasted with a good high pressure washer - some little amount of the looser stuff came off. I haven't used a soda-blaster as I was hoping for something that I could do myself (money is not a non-issue, to say the least). I am hoping to give a couple of 2 part barrier coats prior to applying the antifoul.
Cheers!
JeremyFowler is offline   Reply With Quote
Old 30-07-2021, 23:03   #2
Registered User
 
gamayun's Avatar

Join Date: Aug 2013
Location: Oakland, CA
Boat: Freedom 38
Posts: 2,503
Re: Removing old anti-foul bottom paint. Thread?

I spent about 5 days with a young hired hand and a circular sander removing 30 years of built up bottom paint on a 38-foot monohull. It was not the most efficient but it also didn't dig into the gelcoat like a bad blasting job that I had tried on a 20-footer once.
gamayun is offline   Reply With Quote
Old 30-07-2021, 23:26   #3
Registered User

Join Date: Oct 2017
Posts: 5
Re: Removing old anti-foul bottom paint. Thread?

Try using some paint stripper to soften the antifoul and just scrape it into a bucket for disposal. You might use quite a few litres of stripper and several coats. But the method is way more friendly than using noisy, dusty power tools. Turn on the radio and enjoy the results.
johnzo is offline   Reply With Quote
Old 30-07-2021, 23:31   #4
Moderator
 
Pete7's Avatar

Cruisers Forum Supporter

Join Date: Aug 2009
Location: Solent, England
Boat: Moody 31
Posts: 18,423
Images: 22
Re: Removing old anti-foul bottom paint. Thread?

I watched this recently and wondered if it was worth a go for a one off job. Dewalt also do a similar attachment widget:

Pete7 is offline   Reply With Quote
Old 30-07-2021, 23:44   #5
Moderator
 
Pete7's Avatar

Cruisers Forum Supporter

Join Date: Aug 2009
Location: Solent, England
Boat: Moody 31
Posts: 18,423
Images: 22
Re: Removing old anti-foul bottom paint. Thread?

How about one of these for the keel, its a Tercoo rotary blaster:

Pete7 is offline   Reply With Quote
Old 30-07-2021, 23:50   #6
Registered User
 
Fore and Aft's Avatar

Join Date: Jan 2015
Location: Gympie
Boat: Volkscruiser
Posts: 2,667
Re: Removing old anti-foul bottom paint. Thread?

Jeremy if your not going to pay for soda blasting or a light sand blast then you just have to suck it up and do it manually. These Sandvik scrapers work pretty well and produce good results.
I have also used an antifoul paint stripper that you put wax paper on top after you have spread the gel. The results were ok.
Cheers
Attached Thumbnails
Click image for larger version

Name:	Scraper.jpg
Views:	78
Size:	15.2 KB
ID:	243029  
Fore and Aft is offline   Reply With Quote
Old 31-07-2021, 00:56   #7
Registered User

Join Date: May 2014
Boat: Shuttleworth Advantage
Posts: 2,246
Images: 2
Re: Removing old anti-foul bottom paint. Thread?

Wet sanding with an compressed air rotary sanders. It is a truly horrible job.
Tupaia is offline   Reply With Quote
Old 31-07-2021, 01:09   #8
Registered User
 
wolfgal's Avatar

Join Date: Jan 2015
Boat: been sitting it out
Posts: 821
Images: 1
Re: Removing old anti-foul bottom paint. Thread?

following...

i spent about ten days with a circular sander on the belly of a 47' monohull a few summers ago... and it was a very tough, not-so-satisfying job. and, even though i wore a mask(s), ended up coughing for three weeks.


whatever you chose, chose high-quality protective gear too
__________________
“Though we travel the world over to find the beautiful, we must carry it with us, or we find it not.” Ralph Waldo Emerson
wolfgal is offline   Reply With Quote
Old 31-07-2021, 10:58   #9
Registered User
 
dadster3's Avatar

Join Date: May 2019
Location: Fredericksburg, VA
Boat: Nonsuch 354
Posts: 159
Images: 1
Re: Removing old anti-foul bottom paint. Thread?

I am doing my boat now, and it is perhaps the nastiest job I have ever done. Summer heat in 90s doesn't help.



Blasting is one way to shorten the task, but keep in mind that it is not cheap. The blasting and all the dust/mess mitigation put the price for my 33' at close to $2000. After that you will need several epoxy barrier coats, then 2-5 new topcoats of a high quality bottom paint. For me that would be prohibitively expensive -- I estimate $5 - $7K.


So I have opted to scrape the loose paint, sand and feather the edges, prime the bare spots with some left over paint from the last time, then roll on 2 new topcoats.



Unless you can pay someone to do it, you will have to just suck it up and take your ass-whipping.
__________________
You miss 100% of the shots you never take. (Wayne Gretzky)
dadster3 is offline   Reply With Quote
Old 31-07-2021, 11:15   #10
Senior Cruiser

Cruisers Forum Supporter

Join Date: May 2013
Location: Oregon to Alaska
Boat: Wheeler Shipyard 83' ex USCG
Posts: 3,499
Re: Removing old anti-foul bottom paint. Thread?

Sea Hawk stripper works really good. Depending on how thick you put it on the stripper can remove all layers at once. It removes all types of marine coatings, not just bottom paint. Usually you can buy it on Amazon or ebay for a lot less than a marine store.
Attached Files
File Type: pdf Sea Hawk TDS-1280-Paint-Stripper.pdf (803.0 KB, 72 views)
Lepke is offline   Reply With Quote
Old 31-07-2021, 19:35   #11
Registered User

Join Date: Jul 2007
Location: Grant, Fl
Boat: Gemini 105M, 34
Posts: 94
Re: Removing old anti-foul bottom paint. Thread?

Several years ago I removed gummy vinyl bottom paint from a trimatan using a seven inch air powered grinder with 26 grit fiber discs. I wore a mask and maybe snorkel and kept a hose aimed on where I was grinding to cool it off. If you use discs (and holder) with large holes in it, you can easily see when you are thru the paint. The high volume of water kept it cool and one disc lasts for ever.
captnknopf is offline   Reply With Quote
Old 12-08-2021, 02:30   #12
Registered User

Join Date: Apr 2017
Location: Auckland, NZ
Boat: Cavalier 39 Mk1
Posts: 63
Re: Removing old anti-foul bottom paint. Thread?

A bit of report back.... I've had a fair bit of assistance from an electric wood planer. You have to resharpen the blades regularly though. And it kicks up the same amount of dust as a sander. After planing the worst off, then an orbital sander. Not sure if it's the best way yet, as I have still got 70% to do.
JeremyFowler is offline   Reply With Quote
Reply

Tags
bottom paint, paint

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Price of SeaSpeed V10X in the US - the anti-stick anti-foul Dave_S Construction, Maintenance & Refit 3 08-08-2020 00:38
Anti foul, bottom paint, soft, medium or hard? gunnado Construction, Maintenance & Refit 108 28-04-2017 18:09
Quantity anti-foul paint for 36' mono? MondayNever Construction, Maintenance & Refit 22 13-10-2015 15:00
Bottom cleaning without rubbing away anti-foul simonpickard Construction, Maintenance & Refit 21 08-04-2015 11:58
Anti-Foul Paint Question - Important! Panamajames Construction, Maintenance & Refit 7 07-01-2010 05:35

Advertise Here


All times are GMT -7. The time now is 01:57.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.