My 25d sits on lake grapevine in north Texas, fresh water. Last bottom job was 11/16 and the on lake marine service has retired. Had a scuba cleaning/inspection in May 2020 and reported good condition of bottom paint, but I am concerned about blistering if left much longer.
Off lake bottom job with hauling is $3000. Should I be concerned about bottom or let it ride for a couple of years with the scuba cleaning? any re ports of blistering cd gel coat ?
All previous bottom jobs at 3 year intervals, no blistering, boat in water year round.
Cape dory blisters
Moderator: Jim Walsh
-
frankfurder
- Posts: 125
- Joined: Feb 11th, '06, 11:47
- Location: Cape Dory 25dLake Grapevine, Texas
Re: Cape dory blisters
To the first order, blisters are unaffected by bottom paint. Bottom paint contains various biocides to kill or retard the growth of marine life. It is not impermeable. Blisters are caused by pinholes in the gel coat which allow water to seep into the glass layup, expand, and create the blister. To seal the pinhole, you need to use an epoxy barrier coat which is water tight and applied beneath the anti fouling paint.
Thus, if you never bothered to anti foul, your boat might look like a self contained marine ecosystem and sail about as well as bed mattress, but the blisters would not be any worse. Either you have them or you don't.
I note that to "first order", because I have heard (but cannot confirm and am skeptical) that some types of weed which attach to bottom have a tap root with which it tries to anchor itself. These weeds can worsen blisters as they enlarge smaller holes which might have been partially thru the gel coat into larger holes which can penetrate the gel coat.
Steve
Thus, if you never bothered to anti foul, your boat might look like a self contained marine ecosystem and sail about as well as bed mattress, but the blisters would not be any worse. Either you have them or you don't.
I note that to "first order", because I have heard (but cannot confirm and am skeptical) that some types of weed which attach to bottom have a tap root with which it tries to anchor itself. These weeds can worsen blisters as they enlarge smaller holes which might have been partially thru the gel coat into larger holes which can penetrate the gel coat.
Steve