I have a friend with a 38 ft Bavaria, last time it was anti fouled he was told that osmosis was appearing. He told me
he was considering getting the boat soda blasted and the osmosis dealt with. Should he do this at this early stage or
does he need to wait until a lot more blisters appear ??. If the job is done too early is there a risk of blisters appearing
at a later stage, or, once the job is done it stays done and no more trouble ??.

Ramona said..
Soda blasting is for delicate cleaning, things like aircraft undercarrages etc. Sand blasting or some other media would be required to open blisters. I would suggest your mate tries some other yard or does the job himself. Just repair the obvious blisters and repaint and get the boat back in the water. There are less sharks in the water.

boom !......tish !!!

MorningBird said..
I had MB soda blasted to remove the antifoul. It won't remove blisters, just expose them.
As it turned out there were no blisters but I ended up with a lovely smooth bum and a much faster boat. And the knowledge there wasn't a problem under 1/2" of antifoul.

Can I ask how long ago and how much it cost?
cheers

I soda blasted my 34ft a few years ago then used a dremel to bore out any osmosis. Dried out the hull for about 4 months then expoxied and finished off with a couple of barrier coats. Problem appears to have been solved, last two haulouts have no problems or issues. Main trick was to high pressure clean the hull weekly to remove any crap that had oozed out of the hull. Then sticky tape a few exposed spots to ensure the hull had dried. Once I stopped getting moisture appearing on the inside of the plastic I knew I had a dry hull.

I think the soda blasting cost around $1,000 and total cost was around $6k.

Ilenart

Cockpit said..

MorningBird said..
I had MB soda blasted to remove the antifoul. It won't remove blisters, just expose them.
As it turned out there were no blisters but I ended up with a lovely smooth bum and a much faster boat. And the knowledge there wasn't a problem under 1/2" of antifoul.

Can I ask how long ago and how much it cost?
cheers

About 5 years ago at Sirsi in Pittwater. It was done with other work but all up with an antifoul and prop speed about $5,000.

The soda blast only cleans it doesn't it. The actual treatment entails the gelcoat stripped off...what then ?. Does it
have to be out of the water for any length of time to dry out etc ...is it a slow process ?.

Hi Sam, It's not so much the drying but the flushing of the chemicals out of the laminate..... then drying. If you don't neutralise the chemicals then no amount of drying will get rid of the problem. They will come back.
Lots of flushing with fresh water.

samsturdy said..
Wow....I've just read the post about vinyl wrapping and wondered if that could be a way out for him.

A few small blisters are easily ground out, repaired and top coated. Unless it is extensive and serious just repair it as needed.