Best tool for removing old hard bottom paint

[glenn.225]

Originally Posted by skipperpete

I did the bottom of my boat in a yard with very strict EPA rules.... no dust, no wet sanding, all debris to be captured..... but I was reluctant to shell out $1500 for a vacuum pump and R.O sander so I did the whole bottom with a Bahco tungsten carbide scraper. I caught ALL the removed antifoul on a big plastic sheet.... hard work but really efficient with the thick layers of ancient antifoul.

I did the bottom of my Vega using a similar scraper 12 years ago. Took two long days of very hard work, and I was in pretty good shape then. Don't know if I would want to do it again. But it produces great results. After that, I applied 2 or 3 layers of Interlux barrier coat and VC17 (since I'm in freshwater). Since then, I pressure wash when it comes out of the water in the fall. In spring before splash, I rub the bottom with a 3M green pad and roll on a coat of VC17, all done in a couple of hours.
There is no build-up and I have a smooth bottom [emoji41].

[Scubaseas]

Your phone to call someone to soda blast it.

If you really must random orbital sander (I like Bosch 5" or 6" but YMMV) with dust collection and 36 to 80 grit paper. Chemical Stripper works but largely depends on what paint is on there. Water based ablatives come off easy, epoxy hard coats not so much.

[Kd9truck]

I am with the soda blasting team on this one, sanding of any kind will create dust you will inhale regardless of the collection system, Including the feist tool system which is really the best out there.
The chemical load in those layers of paint is designed to kill life indiscriminately.

[Cpt Mark]

If you are going to sand it, full face mask respirator. Long sleeve cotton shirt(s) and long pants and gloves.

Last time I had to do mine I went to a yard that allows diy. They said they had to prep the boat for painting but I could paint it. Then we started talking rates for haul, set, launch, pressure was, lay days etc. In the end, they painted the hulls for an additional $600. (total $2200) and I supplied the paint. I chose this option because if they did the entire job, there were NO lay day charges. I had other stuff to do and my boat was out of the water for 2.5 months in part because they didn't have crew to work enough.

[JBsurfin]

Originally Posted by OldManMirage

Well, I was planning to haul out tomorrow but I have put it off for a little bit longer while I get a few more of my ducks in a row.

One task I may be doing myself is the bottom job.

I would like to know what tools - such as disc grinders/sanders or whatever - you have had personal success with and can recommend for taking the old paint off/down. I'm not sure if I'll go all the way to gelcoat. I want to get it smoother than it is now, but if I don't HAVE to go all the way I won't. I don't have blisters.

These should be things I can still get today through Amazon or retailers.

Thanks for any help in advance.

Having stripped the bottom of 3 boats, I just got an estimate to soda blast my current 37' Dickerson. For 1850.00, its not worth my time, health, or body to do it again. Its a dirty and long hot day(s) Let alone the Yard wanting proof of environmental coverage(which I have) If the yard does it, it their issue.

[Joli]

Best tool.

A check book.

[Icarus]

Originally Posted by OldManMirage

Well, I was planning to haul out tomorrow but I have put it off for a little bit longer while I get a few more of my ducks in a row.



One task I may be doing myself is the bottom job.



I would like to know what tools - such as disc grinders/sanders or whatever - you have had personal success with and can recommend for taking the old paint off/down. I'm not sure if I'll go all the way to gelcoat. I want to get it smoother than it is now, but if I don't HAVE to go all the way I won't. I don't have blisters.



These should be things I can still get today through Amazon or retailers.



Thanks for any help in advance.

Paint stripper works well and it's quick, I had the same problem of a rather heavy build up of antifouling. I did it in small sections, roll on some stripper, about a section of a m² or so, wait 20 minutes and easily scraped it off on to a drop sheet.
Wear gloves and good goggles
Wash down
Tried to sand it ( Festo 150) very slow and clogged sanding discs.
Good luck

[OldManMirage]

Originally Posted by Joli

Best tool.

A check book.

Lol, yeah you bet !

But it looks like I may not have to worry about it at this point, I have a signed contract on the boat. It's not sold yet but that's a good sign.

Of course, there's always the next one to start thinking about !

[Shaneesprit]

Originally Posted by JimsCAL

Removal down to gelcoat is a hard nasty job. Using a chemical stripper is probably the best DIY method, but still a lot of work. If just smoothing things out prior to adding a coat, a random orbital sander will work. Use a rough grit like 40 or 60. If you decide you want to remove everthing, hire a pro to come and do it.

Chemical Peel is the way to go, beyond me why anyone would choose to sand that off

[sailorboy1]

Originally Posted by OldManMirage

Well, I was planning to haul out tomorrow but I have put it off for a little bit longer while I get a few more of my ducks in a row.

One task I may be doing myself is the bottom job.

I would like to know what tools - such as disc grinders/sanders or whatever - you have had personal success with and can recommend for taking the old paint off/down. I'm not sure if I'll go all the way to gelcoat. I want to get it smoother than it is now, but if I don't HAVE to go all the way I won't. I don't have blisters.

These should be things I can still get today through Amazon or retailers.

Thanks for any help in advance.

the best thing is after haul out REALLY go at it with the pressure washer, even if you have to slip the guy an extra $20+. if you can not blast it off just rough it up and paint over it

that is cruiser answer not a racer answer

[bpappas]

Originally Posted by skipperpete

I did the bottom of my boat in a yard with very strict EPA rules.... no dust, no wet sanding, all debris to be captured..... but I was reluctant to shell out $1500 for a vacuum pump and R.O sander so I did the whole bottom with a Bahco tungsten carbide scraper. I caught ALL the removed antifoul on a big plastic sheet.... hard work but really efficient with the thick layers of ancient antifoul.

I second Bahco tools. I use them religiously.
-Bruce

[Greg K]

Just did the job on our Shannon 28. Scraped off 3 layers of hard paint with a Bahco two handed scraper and then sanded down the old barrier coat with a Bosch 125 mm Professional orbital sander down to gelcoat. Took 10 days.


Followed up with a proper cleaning and 5 coats of Gelshield 200 and 3 coats of Micron 350 bottom paint.
Excellent results but not a job I would ever want to do again.

[slugsgomoo]

Originally Posted by Don C L

I used an orbital sander last time and it worked, but the vacuum filter clogs up fast and you gotta wear a full body suit and a good respirator (at least I did.) I did not take all the paint off, that seems completely unnecessary to me. The previous owner put a layer of red paint on first when he did it and subsequent layers are blue. I just took it down to where I started to see red and called it good. I am going to try skipperpete's idea of a scraper the next time, which will be soon.

Make sure you use a bag in your vacuum, I wish I had started using them 10 years earlier. Not only do you get less fine particulate out the exhaust, the filters last 10-20x longer and the bags are cheap.

I take my bottom paint down until I can start seeing the barrier coat (it was always interlux interprotect, but this time we did Sea Hawk's tuff stuff (not the low VOC)), make sure everything looks good & we're still blister free, and then it's time to paint.

I also spent the extra $$ to have the boat re-blocked this time, because contrary to boatyard lore, painting the block/pad spots and then splashing because "the paint will cure in the water" is dumb, and every paint I've used says 24-48 hours curing before splash. Last time out it was super obvious where the "painted in the slings" sections were because they were miserably covered in hard growth. so far in the water things are looking good this time around, so I'm hopeful that the extra bit of money was worth it.