Sanding bottom paint off

[Ryban]

Note: This is not a discussion about the best way to remove bottom paint, it's a discussion about the least-painful way to remove bottom paint with vacuum sanders.

The boatyards around where we are only allow vacuum sanding for removing bottom paint. Soda blasting, chemical stripping, and even scraping are not allowed. I don't understand why scraping isn't allowed, given that you could put a tarp down and collect nearly 100% of all material removed from the boat, but it is what it is.

We're not interested in sailing elsewhere to haul out right now, so let's keep this on-topic.

If we plan on removing our bottom paint to prepare for a copper coat application, I'm going to need the most efficient way to sand the material off in a form that is compatible with vacuum sanding requirement. Belt sanders remove a lot of material quickly, but can they be contained with a vacuum attachment and a suitable high volume shop vac? A random orbit sander would be a slog.

The yard also says "commercial grade vacuum sander" , but it's not clear to me qhat qualifies as commercial grade.

[thomm225]

Our yard used to allow us to sand with a tarp under the boat to catch the dust, but that has now changed. Tarp photo from 2018. Completed Bottom Job photos from 2019 and 2024.

Normal vacuum orbital sanders are not allowed either.

The yard required a full vacuum set up.

What they did allow was an orbital sander attached to a Wet-Vac, and I was able to adapt my sander to this. New filters were required for the wet-vac to make it work well enough. They had to be replaced during the sanding process.

If they see dust flying, they will stop you. EPA does random checks of the yard's runoff.

As far as an orbital sander, I have used one to sand the bottom of my boat 4 times. I just left the yard on 29 February 2024 after the 4th time I did the bottom.

[HopCar]

I’d ask the yard what other people have used that worked well.

[thinwater]

Bosch 6" dual mode orbital. MUCH faster than standard RO sanders. It's what the yard here uses for stripping. Good vacuum set-up. Not too expensive.

It is not a sander I would use for regular sanding. It's a beast.

Not saying it's easy. I watched a guy take several days to strip a 40' boat. But the best option.