Yard shenanigans: watch how they block your keel (and questions)

[Patches]

When I hauled out on Thursday, I was anxious to see what kind of scrape I put on the bottom of the keel last fall when I did a very slow "touch and go" on a rock.  Right after it happened, I sent a diver down to assess things and he was largely dismissive. Well it was definitely a gouge that needed some filling and epoxy.

While pressure washing, the keel otherwise looked great. No cracks in the hull/keel joint.  Everything looked tight.

When they went to block the boat in the yard, I specifically said to the lift operator to make sure the keel wasn't supported/blocked too far aft.  I recall reading that this can lead to cracks developing in the hull/keel joint.  So I specifically asked if the placement of the blocking--aft of where the gouge was on the bottom leading edge--was sufficient to support the keel while allowing access for the repair.  "No problem."

30 minutes later I was taping up the waterline when I noticed 3 cracks:  (1) Forward/leading edge where the hull meets the keel (above the hull/keel joint (one inch), (2) at the forward end of the hull/keel joint (about 6 inches long), and (3) at the aft end of the keel where it meets the hull (one inch).

I immediately had them come over and re-block the boat.  By this time I had a pretty foul mouth.  To their credit, they owned it and said they would take take of it.  They put me in touch with a local keel repair guy who had the following recommendations:

1.  grind out the cracks

2.  check the keel bolts for tightness and applicable torque values

3.  apply West System or "G Flex" resin and biaxial cloth to the cracked areas, fair, sand, barrier coat and paint.

Anyone been through this and can comment?  He was ready to go today, but I told him to wait until I was able to educate myself a little but more on the long term performance of this proposed fix.  My call to another yard in the area essentially agreed with this proposed fix.

Would appreciate the input of any who have been down this road. I really don't want to haul out again in two and have new cracks--assuking no more "touch and gos."

Thanks in advance.

Patches

[Stu Jackson]

Patches, I'm sure you've seen this one from just this last week:

https://c34.org/bbs/index.php/topic,10577.0.html

[KWKloeber]

The method/materials are appropriate. Either biaxial glass (what I used in the '90s) or I might choose carbon now. But is he going to take down the fairing on all the joint and band it ( the proper way) or just where it's cracked (a lame job.)

Not saying that this is your situation — but on my 30 I had about the same amount of cracking/water leaking out the cracks. When I started grinding I found it way more extensive (in both length and depth) than I expected.  About 1/3 the bedding was toast - punky like wet gypsum drywall.  Water had made way down the bolt threads and attacked the bedding (polyester is hydrophilic, the characteristic that also leads to hull blisters.)

So, after excellent discussion with the folks at West Systems, I decided to drop the lead and rebed it all. Catalina (a/k/a Frank) was less than useless, in fact very detriment to the final outcome.)  Could I have gotten by grinding/fixing just the worst areas - sure. But I'm not sure how well I'd sleep and when I'd be back fixing other areas.  The remaining mung bedding was competent- like nuclear power plant concrete. I went through a dozen carbide cutting devices getting through it.  Per WS recommendation I rebed with 5200 (probably didn't need keel bolts) and banded w/biaxial.
Pics here:

https://groups.io/g/Catalina30/album?id=63662


The moral is that damage is oftentimes more than skin (or fairing) deep - so make sure you get the whole picture decide accordingly.

Good luck with it 👍🏻

[Patches]

Re "banding the whole joint."  This did not come up.  Again, there is one hairline crack, about 6 inches long on the leading edge of the joint.  So I gather it makes sense to explore the continuous nature of that crack by grinding it out and then decide whether to "lap" the joint.  Actually, he will be using a larger dremel-type tool with a cone shaped bit which, as he showed me on another boat, makes a pretty tidy "v" shaped opening of the crack.

The other two cracks are at the front and back edges of where the keel meets the hull (not on the keel/hull joint), and show as 1" hairline cracks.  I take it "lapping" is not appropriate here.  I am familiar with lapping of the hull/keel joint as I could see this was done by a prior owner of a prior boat of mine.  It would seem this is overkill, but I guess he needs to get into the crack to determine whether it is appropriate in this case.

Many thanks for your prompt responses as I've got to approve work today.

[Patches]

All is well.  It turns out the cracks caused by the improper blocking were actually superficial and confined to the outer fairing material on the keel.  These were ground back, filled with G flex epoxy, and a layer of fiberglass cloth added. Then fairing, sanding, barrier coat and bottom paint.  Results look very good.

Hung in the slings for about 2 hours before launch yesterday.  No new cracking and everything looks tight.

Patches