A couple of questions on osmosis and buying a boat

[boatpoker]

Osmosis Testing in Boats

Moisture Meter Mythology

[yeloya]

We did a lot of osmosis treatment. Of course if you can afford an epoxy boat (few can..) it's best. Almost all of boats are GRP and mostly isophtalic resins are used. I have never heard any osmosis on these boats. FP has used sometimes back orthophtalic resins which created a lot of problem. If treated properly, osmosis won't come back.
As one forumer said, if there is no sign of osmosis in 12 years, there won't be any. It's easy to detect the lamination with rubber hummer and moisture meter. If the boat remained very long time on hard, the readings should be very very low..


Cheers


Yeloya

[boatpoker]

Originally Posted by yeloya

We did a lot of osmosis treatment. Of course if you can afford an epoxy boat (few can..) it's best. Almost all of boats are GRP and mostly isophtalic resins are used. I have never heard any osmosis on these boats.

Iso resins did greatly reduce the issue, they did not eliminate it.

[pillars]

Originally Posted by Bean Counter

What brand model and year cat are you looking at?

It's a 12 year old Leopard.

[Bean Counter]

I don't recall Leopards having an osmosis issue. I think they also use Vinylester for the resin which if applied properly is apparently less prone to water absorption. This is from my memory of researching Leopards 4 years ago, but no personal hands on experience regarding Leopards.

[Cadence]

Originally Posted by boatpoker

Iso resins did greatly reduce the issue, they did not eliminate it.

As I recall, one of the advantages of Iso resin is that it does not leach out the MEK, suitable for tankage. I can see that working the other way and not leaching in water. I can't help but wonder if blistering is not related to inadequate resin in an effort to keep weight and cost down? I know, vacuum bagging and all that but are there still voids in total saturation at points?

[danielamartindm]

I'll pass on some advice from my grandfather: If you think there are a thousand and one ways to go crazy, there ARE.

[hellosailor]

Blistering and osmosis were a mystery solved in the late 80's or early 90's, so any professionally built boat that is now only 12 years old (built in 2006?) should not have osmosis issues. Check the reputation of the brand and builder, just in case, but it should not be an issue.

Going forward of course, you can always have a barrier coating and fresh bottom paint before you launch, if you want the extra "protection", regardless of any issues now.