2 2011-11-03 01:53:03 (edited by Ian Malcolm 2011-11-03 13:18:15)
Re: KEEL DAMAGE
When you are repairing impact damage in GRP, all shattered, crushed, splintered and cracked glass and resin *MUST* be cut away, back to sound GRP. Even small cracks must be ground out. After this, all edges must be bevelled by grinding back by at least a 10:1 ratio (e.g. 1/4" thick GRP needs to be ground back 2.5") before you can start building up replacement laminate layer by layer to the same thickness (and specification if it can be determined) as the original.
I think some of your keel damage when cleaned up will be over a foot across, and much of the front of the keel will need rebuilding.
Unless you can get expert assistance, IMHO this is not a good one to learn on.
For: no need to colour match Gelcoat repair and blend in and polish ;-)
Against: 1. Under water
2. Large
3. Structural.
:-(
Re: KEEL DAMAGE
Yes, ouch for sure!! I'm gonna hire a pro for this repair. Thanks for your input...
5 2011-11-03 15:51:56 (edited by Ian Malcolm 2011-11-03 16:02:27)
Re: KEEL DAMAGE
Probably just as well. Ask the pro if they mind you watching or even if they are willing to teach you the basics. ;-)
I found some similar but smaller damage that had been bodged many years ago (newer gelcoat on top of crushed GRP) and ground out about a 6"x8" area and fixed it last winter. I have done quite a few below the waterline GRP repairs and modifications on our CO26 (including refitting the stern tube, a new solid GRP depth transducer fairing block and removing all traces of the old transducer mounting hole) but might even call in a pro myself if I had as much damage as you do.
Re: KEEL DAMAGE
Was the boat taking on water? Judging by the depth of the damage in the picture with the barnacle - I'd even be leery of any "professional" who would only complete that repair from the outside. There would be access (although it sucks working in there) from the V berth lockers.
Although not specifically Co26 related, I had a late start this year as I took on a contract installing a bow thruster tunnel in a Beneteau 473. First job ever that I didn't have anybody walk over and tell me what I was doing wrong... Those were two pretty big holes to cut in a very nice boat..... I'll someday get a website going with some pictures...
Re: KEEL DAMAGE
The boat did not take on water thankfully, the damage does not seem to be deep enough that it would need work from the inside..hopefully...
Re: KEEL DAMAGE
I think it *MAY* be far enough down the keel to be backed by the encapsulated ballast. However the bond of the encapsulation to the hull at the front of the keel should be checked on the inside. I think it will be below the sole just aft of the V berth. If you have any built in tanks in the keel you may have a whole world of grief.
How old is your boat? I hope she's one of the newer JJ Taylor ones with lead ballast as you really dont want water getting to encapsulated cast iron ballast as it rusts and swells.
Re: KEEL DAMAGE
It's a 72 JJT. Don't have any tanks installed...now I'm starting to get worried. Will have a look from the inside for sure!!
10 2011-11-05 14:36:14 (edited by Ian Malcolm 2011-11-05 14:37:31)
Re: KEEL DAMAGE
So you have iron ballast. Not a problem as long as there is a good seal over it and no holes in the keel skin. Obviously its a good idea to get everything as dry as possible, but a little moisture wont cause significant rusting over the long term provided any cracks in the top of the encapsulation are made good so more oxygen cant get in.
Re: KEEL DAMAGE
thanks for this info! I was not 100% sure about the ballast. I'm grateful for this site.