I sacrificed my new carbon/kevlar Nordkapp to the rocks in the Grand River on Saturday. I knew the water was going to be low, but I could not get comfortable with using any other boat for that long of a distance. I think the majority of the scratches will clean up with rubbing compound, and a few will require a wet sand with 1500 first. There are two marks about three inches long that appear to be cloudy scars under the surface. One has chipped through to the weave in a few small BB sized areas, the other is smooth on the surface but cloudy below it. My question is this. Do I need to grind out these marks before laying in clear gelcoat? If I do will this make most of the cloudyness go away? There are no soft spots or structural issues from any of these marks, and as such I don’t want to put more gelcoat on if it won’t make a cosmetic improvement(except for the exposed weave). This is my first clear gel boat and I need some advice from those of you who have faced this before. Thanks, Bill
my guess…
…is with use of a automotive type rubbing/buffing compound, and buffer, all the superficial surface scratches will come out. The “cloudy” type damage, in my opinion, probably is subsurface separation of gelcoat and base layer, caused by the boat banging against the rocks and flexing too much. that will probably best be dealt with by grinding it out some( very carefully) and refilling the area. it would even be a good idea to contact your dealer and ask their advice or the company directly. I’ve had good luck sending and receiving emails replies from companies.
You need to sand out the damage
If you just pack gelcoat into the gouges, it will likely crack and come back out again. Sand the area and feather the edges, just make sure you don’t sand into the Kevlar, as it will turn to fuzz (you can use a scraper rather than sanding and avoid the potential fuzz issue). Once you have the area prepped, you can apply new gelcoat. Build it up until it’s a bit proud of the original surface, then wet sand it until it’s blended in. You’ll probably need to sand through 1200 or 1500 grit, then hit the area with rubbing and polishing compound to duplicate the original gloss.
Thank you. I figured this was the case.
I am a little nervous about hitting the weave. I will sand/grind slowly in hopes of avoiding it. Good news is the areas are still rock solid. Bill
more questions about gelcoat repair
Since this thread concerns gelcoat repair, I hope no one will mind if I ask a different gelcoat repair question:
I have a 30 year old kevlar canoe with clear gelcoat (Sawyer DY Special). It has the usual scratches that I would like to improve but the surface is more deteriorated, probably due to being stored in a shady but only partially covered location for several years. The best way to describe the problem is that it looks to me like the gel coat has simply “worn off”. I’d say this is the appearance of about half of the wetted surface area. As a result, there is substantially more surface drag and the boat is somewhat slow. most of the gel coat above the waterline seems fine.
I’d like to repair it but I am unsure about how to prepare the surface for a new gel coat. Sanding seems like a real risky maneuver as everyone warns about turning the kevlar into fuzz.
Have I ruined it beyond reasonable repair? It is stored in a shed/boathouse now but is it too late for any reasonable improvement? If it can be restored, what types of products are needed? If we’re talking about “replacing” more than half the gelcoat, about how much gelcoat product should I expect to buy?
Any advice or guidance to reference materials would be appreciated.
In the process
I have a wenonah kevlar boat where the “shine” is missing on most of the boat. I took a large scotch brite pad , red in color around 1000/1200 grit, from a wood working store and scrubbed the whole boat. The shiney spaces I hand sanded with 100 grit paper to rough those areas up. Shop vac’d the whole boat and cleaned boat with denatured alcohol. One coat of epoxy was applied. Varnish this week. The boat looks good with just the epoxy. Won’t be a show boat by any means but will look better then what it does and hopefully perserved the boat for years to come.
Brian
Perhaps this
Saw this in Savanah and thought it might be worth trying. No further data on it from me other than I took a picture of the package to remember the idea.
Ding All for surfboards.
http://www.jamestowndistributors.com/userportal/show_product.do?pid=12489
Just an idea.
See you on the water,
Marshall
The River Connection, Inc.
Hyde Park, NY
www.the-river-connection.com
The Fuzz
The problem I see is that if the gel coat is no longer well adhered to the fabric below, you will have to sand down to the fabric. or the new one will fall off is my guess. If you do sand down to the kevlar, you may get some fuzz. But, that’s not a big deal IMO since you are covering it. I found out that the fuzz does get removed just fine with something like 220 grit paper or a scraper.
I think there may be a misconseption about the “fuzz”. There are two kinds of problems with the kevlar. The first is the fuzz that sticks-up like tiny hairs. This I think is fairly easy removed if you have a sound foundation. You will have to carefully sand them down or otherwise remove them (carbide scraper may work). The problem that most are referring to, I think, is that sanding does not polish kevlar like it does say fiberglass or carbon. But sandind does get rid of the fibers in many cases, so your next coat will completely cover the sanded area. All you need is to sand that coat and not sand again through to the kevlar.
That tactic worked for me on my recent paddle making endeavor - the carbon/kevlar weave I worked with was similar to what’s in your Valley boat. Sanding down the fuzz was successful to a point where there was no fuzz - just the kevlar fabric level with the rest of the layup. A coat of epoxy in my case covered it nicely and that could be sanded to as much shine-ness as desired. In your case it will be the gel coat playing that role.
I’d be curious to hear other experiences - mine is based on just a single experiment so there might be other gotchas or exceptions …
YouTube.com
I found this set of videos that may help.
Necky Kayak Composite Gel Coat Repair Part 1
http://www.youtube.com/watch?v=THLDXU9rBBM
Necky Kayak Composite Gel Coat Repair Part 2
http://www.youtube.com/watch?v=i1DcJzH-9AI&feature=related
Hope this helps!
If you want to replace the gelcoat…
…I would suggest removing what’s left, cleaning the surface, then taking the boat to someone who can spray it. I guess it would be possible to do at home, if you have the equipment for it, but it’s probably a job best left to a professional. Bzeka’s suggestion of epoxy and varnish is certainly a viable alternative that would probably be easier for most people to maintain.