Ferro-Cement Paint Removal

[Mike.P]

Hi we are wondering about painting our boat, she is a 42' ferro-cement ketch and her hull is needing a painting. There are a few bits of damage to patch up first. We want to get the old paint off first so I can see the bare concrete and I was wondering if anyone has any magical solution to remove the old stuff? I don't know what it is but it is solid as a rock. Is it necessary to take all of the old paint off first or are we making too much work for ourselves? Any input or advice is appreciated.

[svHyLyte]

Think sand or soda blasting. (Remember to close your through hulls!)

FWIW...

[smallyachts]

I believe I have read that sandblasting is not a good thing to do to Portland Cement. You may want to jump up on ferroboats and read up.

I know I saw some pretty bad results from someone who did that to a Ferro boat several years back. I saw exposed mesh and numerous spots that had to be later faired again.

Apparently sandblasting is very abrasive and Portland is not very resilient.

If you google "sandblasting concrete" all the articles talk removing ingrained dirt and debris. That sounds pretty agressive.

[Boracay]

If the old paint is sound why not sand it back to give a smooth surface and good grip and paint over the top?

You'd need to check with the paint manufacturer as to which paints might suit. Some two pack paints are too aggressive over single pack. Maybe try a small area first.