Blisters on Boot Stripe

[karista]

The Boat was hauled a few days ago for bottom painting and I noticed that I had about 5-6 dime size blisters on the port side only on the  lower Boot Stripe.
This is considerably above the water line so its somewhat of a mystery to me. The yard recommended grinding them down and filling and then paint on an entire new Boot Stripe, say the can't match the Gelcoat color. This seems overkill to me and is quite expensive.
Since they are avove the water line, I am inclined to just not do anything, or would it be advisable for me to use a Dremel tool and simply grind them out and fill with Marine Tex Epoxy? 

[Ron Hill]

Benrd : I got tired of cleaning the white width between the waterline narrow and wide boot stripes so here's what I did. 
I moved the new waterline up into half the width of the wide boot stripe.  That included epoxy barrier coat and bottom paint!!

A thought

[mregan]

When I bought my boat last year, the surveyor noticed small blisters on the boot stripe above the waterline.  He said they were caused by the shrink wrap laying against the hull during the winter.  Moisture got between the shrinkwrap and hull.  With the sun beating on the shrinkwrap, it caused the water to get absorbed and small blisters to form.  They aren't dime sized.  More pencil eraser and smaller. Maybe same thing happened to yours?

[Stu Jackson]

Bernd,

Marine Tex is not the product you should use.  Reason being is that after a year or so it yellows in the sun.  Your best bet, if you're gonna go to that trouble of drilling them out, is to use gelcoat, which is covered extensively in the C34 manual, on this site if you don't have one.  Look in Manuals in the C34 Tech wiki.

Matching a standard Catalina "white" should be a no brainer and if that yard can't do it, either DIY or find another yard that has any brains.

[karista]

Benrd : I got tired of cleaning the white width between the waterline narrow and wide boot stripes so here's what I did. 
I moved the new waterline up into half the width of the wide boot stripe.  That included epoxy barrier coat and bottom paint!!

A thought

Ron

My message was not clear, I had years ago raised the waterline, just like you did by covering the  entire 1" wide lower white stripe with barrier coating and bottom paint. The blisters I have now are on the wide lower colored Boot stripe, my striping is a gray color.

Stu!
I was thinking about using the gray color Marine Tex Epoxy as I have read that blisters should be filled with epoxy not Gelcoat, (The yard was going to fill with epoxy and then paint on a new Boot stripe)

[Stu Jackson]

Bernd,  I haven't used the gray, only the white.  Good luck, the gray might work for you since yoou're doing "on or under" the gray bootstripe.

[pablosgirl]

Hi Karista,

If you are not about to sell the boat, I would not go through the expense of repairing 5 dime size blisters.  This is purely cosmetic.  What if they come back by the next haul out. Repair and repaint again?  Save your boat bucks for when the refrigeration quits or for new sails.  I had a few between the waterline and the boot strip when we were repairing the boat and we just did what Ron suggested and moved the bottom paint edge up to the bottom of the boot stripe.

[karista]

Bernd,  I haven't used the gray, only the white.  Good luck, the gray might work for you since yoou're doing "on or under" the gray bootstripe.

Update
I went to Fiberglass Coatings Inc. they have their big store here and also supply Catalina with their resins etc  and talked to their fiberglass guru in great detail.
His advise was to only use gel coat for any repairs above the water line. Epoxy is not recommended as it will discolor and will also break down if not painted by UV. So, I removed the marine tex that I had applied (should have take your advise Stu) and applied gel coat. The blisters on the boot stripe were not deep and only cosmetic and were easily repaired with gel coat.
I also asked him why my epoxy repairs on my keel are not holding up and come off. He suggested that never to apply epoxy directly to the lead which I had done, but rather sand the lead clean and then within 30- 40 minutes apply a layer of fiber glass, let it cure and then fair in with epoxy fairing compound. So for many years I had done this wrong and the epoxy fairing always came off at the next haul out.

[Clay Greene]

I have about a dozen spots on my keel where water has gotten behind the fairing compound and it has either cracked or popped off.  I asked the Pettit representative about it at Strictly Sail.  His recommendation was to sand down to the lead and apply a metal primer.  While the metal primer is still tacky, apply an epoxy fairing compound and then barrier coat and finally bottom paint.  Going to try it this spring as soon as it warms up. 

[karista]

I have about a dozen spots on my keel where water has gotten behind the fairing compound and it has either cracked or popped off.  I asked the Pettit representative about it at Strictly Sail.  His recommendation was to sand down to the lead and apply a metal primer.  While the metal primer is still tacky, apply an epoxy fairing compound and then barrier coat and finally bottom paint.  Going to try it this spring as soon as it warms up. 

My boat is currently at the largest Boat yard in St. Petersburg, with the identical situation you describe. The yard will sand the affected areas down the bare lead, then within 30 minutes apply Interprotect 2000 epoxy primer on the bare lead only, they will do a second coat, then followed by priming the entire keel with Petitt TieBond primer, then apply the bottom paint. They did not see any need to apply fairing compound or barrier coat on a lead keel.

[TonyP]

some pics of our blisters a couple of years ago in replays 6,7 and 8.

http://c34.org/bbs/index.php/topic,6699.msg44200.html#msg44200
cheers
Tony