Crack repair

[rade0041]

Me again...

I have this damage to the bottom of the transom on my boat (26' water ballast Hunter). It was done by the PO, of course. It doesn't appear to be a structural problem and doesn't leak. My question is what is the pink stuff? Is it the core material or is it some type of bondo repair that someone attempted? My plan was to grind out what I can and build up again with fiberglass and polyester resin and gelcoat. I'm just wondering if I need to do anything with this pink stuff besides grind away any that is loose or cracked before I repair. Any ideas?
Thanks again.

 

[Regular Guy]

That is a well known issue. You will find threads regarding how to repair this joint crack. The old material has to be deeply carved out and resealed. I believe Crazy Dave has explained how to do it in great detail.

 

[rade0041]

I was able to find a little info on this by searching the forums. It seems that I have to dig out the pink material until I get back to solid fiberglass and then fill it in and gelcoat. Would polyester resin and strips of fiberglass mat be acceptable for filling in the area or is there something better I should use?

 

[centerline]

The pink stuff is polyester resin with fillers in it to thicken it... commonly known as bondo... it is ok to use it as a filler where stuctural strenght is NOT needed, or where a rough surface needs to be faired, but it is not a structural product itself...

 

[Crazy Dave Condon]

Ok guys I will tell you that is marine putty between the hull to deck joint covered by gel coat. If you a dremel, dremel out the putty but make sure you clean the fiberglass where it adhered to. Do not go into cutting the fiberglass out so be careful, Clean off with Alcohol or acetone. Then use a good two part epoxy which may take several times to rebuild. I forked the money down but used the best two part epoxy which worked well for me as a dealer over the years called Water Tite. THis is an area I did not screw around with other epoxies and forget the putty sticks gents. Sand off smooth and apply gel coat. Ok guys I did use Krylon white for plastics as in a sense gel coat is a plastic of sorts.

 

[John23883]

This will leak through into the boat if you don't get all the material out that is not tightly attached. I had to remove about 4 feet until I got to the fully adhered material. Then I filled it with bondoglass which has fiberglass in it to give it strength and flexibility. Then topped with gelcoat. As stated you have to carefully remove the bonding material without damaging the fiberglass top and bottom. I used a chisel so I could control it and not damage the fiberglass.

 

[Sailorjohnca]

Just a comment re resin, polyester does not stick any where near as well as epoxy based resins. I would use epoxy for the filler material to, so no comparability issues. Note crazy Dave's comment.

 

[CloudDiver]

The old wisdom was that gelcoat will not adhere to epoxy repairs... West System has debunked that theory with actual testing, go to their website and you can find an article about it. So you can in fact do the required repair with epoxy and then after sanding a fresh application of gelcoat will adhere to it just fine.
As recommended above, grind out the pink filler where it is cracked. I doubt that you will have to grind out as much as John23883 had to, but like he said anything that is cracked or loose must come out... so you may or may not end up removing as much as he did. Interlux Water-Tite (as mentioned by Crazy Dave) is a great (easy 1 to 1 mix) epoxy filler to use. It comes in two sizes right from the SBO store here. Get the smaller size... If you find yourself grinding out as much as John23883 did, I'd get some foam core material and cut strips that will fit the area and glue them in with thickened epoxy rather than gobs and gobs of (expensive) Water-Tite filler. You can use a few layers of 6 oz figberglass tape if you want to cap it, but that may not be totally necessary... I'm a perfectionist so I probably would. For finishing, use Spectrum Gel-Paste. I comes in 2oz jars that are color matched to your year/make. Its basically thickened gelcoat that is very forgiving to work with. A 2oz jar is $25, I think you might need two jars total to cover that area of repair. When you are finished with the epoxy repairs, just sand and fair everything smooth and be sure that the top surface is 1/32" to 1/16" BELOW what the finished gelcoat surface should be so you can apply the gelpaste pretty thick with a putty knife. Once you sand the cured gelpaste flush with the rest of the lip at 120 grit, then sand 220, 320, wet 400, wet 600, and cut/buff with polishing compound; ta-dah.
http://www.spectrumcolor.com/Items.aspx?key=cat&code=K&manu=HUNTER&incl_m=T

 

[Crazy Dave Condon]

Folks, I spenrt many hours repairing many boats with these cracks and what I suggested above worked rhe best over other methods and materials as a former and the largest trailerable dealer for Hunter very much involved with these boats. water tite is the strongest I found over the years in way of epoxy. If you want, you can take fiberglass cloth strands and include that with the water tite. however the last coat should only be water tite. then sand aand apply gel coat or krylon white plastic paint but mask off the area first. I am the one who told Hunter about Water Tite.

 

[Doug J]

Is this crack condition common? Is it due to an impact? Or does it just happen for no apparent reason. I have a 94' H26, I'm gonna look closely to see if mine is developing a crack.

 

[Crazy Dave Condon]

It was marine putty back there and yes it will crack over time. Not really an issue as it was easily fixed. However the bonding of hull to deck is very secure except for the back which is just a filler situation.

 

[Doug J]

I took a real close look at my 94' H26, there appears to be no sign of a developing crack. I sure hope it stays that way. Considering the boat is 22 years old and it didn't happen yet, maybe I got a good one. Fingers crossed...