How to Remove Several Coats of Bottom Paint?

[SDSeville]

I bought a 1989 Bayliner Trophy 2560 and need to repaint the bottom (in addition to a long list of other things). However, there are what looks like many coats of bottom paint on there from the previous owner. To make matters worse, it looks like he just hosed it off prior to repainting. Upon closer inspection, it even looks like he painted over pieces of tape in some places.

What is the best way to remove this? I was thinking many hours with an orbital sander, but wanted to check with you all to see if there is a paint stripper that might help get the majority of this stuff off.

Thanks!

 

[FunInDuhSun]

Pay someone to soda blast it if you can. Chemical strippers do the job but they are expensive, messy and SLOW, not to mention chemical burns to any exposed skin!
When I refurbished my 30 year old Silverton 34C, I tried chemicals but gave up after 1-1/2 days. I discovered the many layers of bottom paint would come off if I used a 4” razor scraper, but it was so sharp the ends could easily dig into the fiberglass. I discovered that using a USED blade worked very well and minimized gouging the hull. Don’t get me wrong- it was a ton of work but it did the job. In my case, it looked like the hull wasn’t sanded before the first layer of paint was applied all those years ago. After getting 95% off, I sanded the entire hull before applying the barrier coats and bottom paint.

 

[Chris1956]

I have had the same experience as Fun. A 36 grit grinding wheel on a grinder on a windy day works, but you can easily gouge the hull. If you gouge the hull, make sure to seal it with epoxy barrier paint.

 

[lprizman]

Find a local responsible mobile blaster....pay to have it done properly and ethically....then let it breath

 

[tpenfield]

Media blasting as suggested or as a DIY, you could try a product called "Peel Away" which will soften the paint and make it easier to remove with a putty knife / scraper.

I would avoid any significant sanding as that approach could result in damage to the gelcoat.

Expect it to take a fairly long time to get the paint off if you DIY.

 

[alldodge]

I paid to have mine removed, then took it back to apply epoxy coating. If your going back with bottom paint only take off the bottom paint and leave any barrier coat that remains well attached.

Have to have good respirator to DIY

 

[SDSeville]

Will products like Peel Away or Petit's Bio-Blast leave the gel coat in good enough shape to not need a barrier coat?

 

[alldodge]

Will products like Peel Away or Petit's Bio-Blast leave the gel coat in good enough shape to not need a barrier coat?

It will not effect the Gel coat

 

[Chris1956]

Gel coats on boats are either porous or waterproof. The stripper you use has no effect. If you don't know if your gelcoat is waterproof, barrier coat it.

 

[SDSeville]

Thanks for all the replies. It is looks like $1000 to blast it. I guess I will just bite the bullet.

 

[lprizman]

Thanks for all the replies. It is looks like $1000 to blast it. I guess I will just bite the bullet.

Good deal... pics???
Before and after...
Need to let er breath before new coat

 

[SDSeville]

Good deal... pics???
Before and after...
Need to let er breath before new coat

How long does she need to breathe before new bottom paint?

 

[alldodge]

How long does she need to breathe before new bottom paint?

Look at what your using. The manufacture will indicate what is required and when. Stuff I used required no breathing room, and sequential coats had a time frame

 

[Scott Danforth]

What I did on the Rogue. 2 rolls of 40 grit and a DA.

Then 2 rolls of 80 grit.

Then sprayed gel.


What my budy did every year on his sailboat. 40 grit on a 8" grinder. A fast pull and grind. Use VE putty to fix divits. Use 80 grit in the DA to smoot the hull

2 coats of barrior coat, 4 coats of bottom paint

 

[lprizman]

How long does she need to breathe before new bottom paint?

As stated the manufacturer has its own suggestion.....my opinion as long as possible.
I grew up a blow boater....we would pull the boat day after Thanksgiving.....sand and remove that weekend.....2nd week of March providing temp is ok...new paint....dunk 1st week of April

 

[SDSeville]

Should I have the drive blasted also or just sand it?

 

[lprizman]

They can do the drive also....less psi...just scraped our outboard down...fresh paint this spring...so a quick power wash and done

 

[SDSeville]

They can do the drive also....less psi...just scraped our outboard down...fresh paint this spring...so a quick power wash and done

Thanks. I assume they tape off the bellows? Just put a new one on and don't want it damaged.

 

[lprizman]

They damn well better properly prep everything.....
They get there and start blasting....shut it down.....
Request before and after pictures from previous projects

 

[lvluck]

Peel Away is a good option to remove the multiple layers of old paint, That's much safer than many paint strippers. After that, you can process painting and waterproof works to prevent corrosion of seawater, and reduce barnacles which slow the speed.