wingless
Active Member
The tools I use are a Festool RO150FEQ sander and a CT22 dust extractor.
My experience is that this is a "clean" process. I wear a dust mask and eye protection, but am clean at the end of the job.
The dust protector requires normal expected maintenance of changing the bag and cleaning the filters to keep it up to snuff. My 38' boat fills four bags to remove the bottom paint.
The best first step is to use a "real" pressure washer, not the "feel good" toys the marina uses. I have a 3.5 gpm / 4,000 PSI pressure washer that removed LOTS of stuff the marina's pressure washer only polished. That is all crud that didn't need to be sanded off.
What I found when sanding off the remaining paint and the factory barrier coat was that I needed a coarse grit to cut through the barrier coat, but that was too coarse for the gell coat. I found that sanding through most of the barrier coat w/ coarse worked well, then I switched to a more fine grit to get to bare gell coat.
The factory barrier coat on my boat was brown and was very tough. There was a thin black coating against the hull that was easy to remove. I would sand until the black just started to show.
Once all the paint was removed I used a fine grit, a block sander and long strokes to have a smooth flat hull.
My boat had factory gell coat defects that became visible only after the paint was removed. I repaired those w/ West System. Now it is perfect.
Here is an image showing the barrier coat mostly removed.
Here is an image after the sander was intentionally tilted, just to show all the layers, just for this picture.
My experience is that this is a "clean" process. I wear a dust mask and eye protection, but am clean at the end of the job.
The dust protector requires normal expected maintenance of changing the bag and cleaning the filters to keep it up to snuff. My 38' boat fills four bags to remove the bottom paint.
The best first step is to use a "real" pressure washer, not the "feel good" toys the marina uses. I have a 3.5 gpm / 4,000 PSI pressure washer that removed LOTS of stuff the marina's pressure washer only polished. That is all crud that didn't need to be sanded off.
What I found when sanding off the remaining paint and the factory barrier coat was that I needed a coarse grit to cut through the barrier coat, but that was too coarse for the gell coat. I found that sanding through most of the barrier coat w/ coarse worked well, then I switched to a more fine grit to get to bare gell coat.
The factory barrier coat on my boat was brown and was very tough. There was a thin black coating against the hull that was easy to remove. I would sand until the black just started to show.
Once all the paint was removed I used a fine grit, a block sander and long strokes to have a smooth flat hull.
My boat had factory gell coat defects that became visible only after the paint was removed. I repaired those w/ West System. Now it is perfect.
Here is an image showing the barrier coat mostly removed.
Here is an image after the sander was intentionally tilted, just to show all the layers, just for this picture.