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PostPosted: Wed Aug 08, 2012 2:03 pm 
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Joined: Sat Jun 02, 2012 10:09 am
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Location: Austin, TX
This will be my first venture into soft spot repair...Going to repair some delam in front of the cross bar (has been stepped on for 30 years by prev. owner). The area is not spongy or soft to the touch, but when when I knock on it you can hear kind of a "thud" sound instead of the "ping" sound that I get on the rest of the deck. If you press on it really, really hard it will flex and I would rather fix it now than later.

Reading up on the epoxy fill method, my question: how deep do I drill my holes as to not penetrate the second layer of glass?

What size drill bit is optimal for the job?

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PostPosted: Wed Aug 08, 2012 4:11 pm 
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83Turbo wrote:
Reading up on the epoxy fill method, my question: how deep do I drill my holes as to not penetrate the second layer of glass?

About 1/8". You don't have to drill all the way through the foam - just enough to get close. You can poke through the foam with the drill bit spun in your bare hands to get down to the second layer of glass.

Beware the point on the end of a standard twist drill. Don't trust yourself to hold the drill to the proper depth. Use a drill stop or a small piece of tubing around the drill bit to control the bit. It will have a tendency to lunge when it breaks through the first layer of glass.

If there is any sign of moisture in the material you're removing, after drilling all the holes, let the boat sit in the sun for several hours to dry out, or else all your work will be in vain.

83Turbo wrote:
What size drill bit is optimal for the job?
As small as possible, but still large enough for the nozzle of whatever you're using to inject the epoxy. Use blue painter's tape over everything! (drill through it). It will save you a lot of clean up later.

Bottom line: be patient, be careful, do it right and you'll forgo a lot of aggravation and re-work. The end result will be worth it.


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PostPosted: Thu Aug 09, 2012 11:39 am 
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Hi,
I am just finishing up on a delamination repair. A tree branch poked a 2" hole in the hull just forward of the front pylon. I had to repair the hole as well as the delamination it caused around the hole.
I used a 1/8" drill . I purchased a set of "drill stops" at Lowes, Home Depot did not stock. I was drilling holes about 3" apart in the area. After drilling I could insert a tooth pick and feel the bottom layer of fiberglass. I probably had 30 or so holes for the area I was working.;
I purchased a "West Systems"105-K repair kit" but quickly realized I did not have anywhere near enough resin as my holes were taking the full volume of the provided syringe. I went back and purchased a quart of resin and small container of hardner. Went really well, just finishing up now.
I used regular masking tape and it was a pain getting off. The blue painters tape would probably work better. When the resin is setting the temperature of the hull surface was 120 degrees vs ambient 81 degrees.
I was told since West Systems is an epoxy, not a poly-ester, Hobie gel coat repair is not compatible with epoxy. Still trying to figure if a one part polyurethane can be used to paint.


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PostPosted: Fri Aug 10, 2012 10:08 am 
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Location: Lake Eden, Vermont
I used a 1 part poly paint by interlux and it worked really great. It's very durable and the color is awesome. The paint is not intended as a deck paint though, it's meant to be a topside paint. Even though it is a high gloss paint I have not had any problems at all with traction. But it's tricky to apply. Have a buddy with you if you decide to go with the poly based paint. I am curious though to see what Mbounds suggests for the deck paint that guy is awesome, he knows everything.

I not a pro and I am not telling you how you should do it, I am simply telling you how I did it.

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PostPosted: Fri Aug 10, 2012 9:35 pm 
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Location: Detroit, MI
I'm not sure I would "fix" the epoxy dots left over from a delam repair.

(If done right - with lots of tape to protect the existing surface - that's all that should be left. If you've got epoxy blobs everywhere, you have bigger problems.)

On the one hand, a delam repair is just buying a bit of time - why throw more money at a cosmetic issue (and polyurethane paint isn't cheap) when the boat only has a few more years in it. This forum is littered with stories of gorgeous restorations that failed almost as soon as the boat hit the water because they paid more attention to the cosmetics than to the structural issues.

On the other hand, it's nice to have good looking stuff.

There are a couple of issues here - one is the poor adhesion of polyester to epoxy (making direct application of gel coat problematic) and the other is the difference in hardness between the epoxy and the existing gel (making getting a fair surface really difficult).

I'd probably take a Dremel tool and "divot" out each of the epoxy dots. Then, having removed the amine blush and roughened the surface in one operation, I would use some thickened gel to build up the surface, sand fair, polish and call it a day. If you wanted to paint, stop after sanding and then apply your choice of paint. Polyurethane (both one and two-part) works well, although unless you have the proper respirator (air supply, not face mask), don't be spraying the stuff. It's nasty.


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PostPosted: Sat Aug 11, 2012 8:05 am 
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In my case I had a 2" hole in the top of the deck which resulted in delamination around the hole, about 8" aft and forward of the hole. Not only do I have the small holes but also a 2" round area of epoxy sanded flush.


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