Hulls Discoloring 2002/2003

Thanks for all the ideas and input (please keep them coming)!

The various fixes sound promising. My plan is to lay a matrix of your ideas on one of the hulls and see which is most effective.

Bottom line, the puddle I sail in has many nice looking, white boats that have far more exposure to the "yuk" than mine, but do not exhibit this problem. If we rule out a manufactured gel coat flaw we are left with only a few things. In the end, I think this will be either 1.) a marine life-form or mineral, as wannahobie suggests, or 2.) my expert may have had a flaw in his process (I'll state for the record, I do not think he took short-cuts or did anything underhanded, but being human could he have missed / forgotten something, or could have delegated this mundane buffing task to someone in his shop who does not share his perfectionist manner. He's a great guy.)

Thanks,

Dan
03 H17 SE
Campbell, CA

This looks like sanding of the hulls and opening the pours of the gelcoat is the likely cause. Stock (sealed) gelcoat doesn't do it... makes sense. That may be why the other boats don't have the issue.

_________________
Matt Miller
Former - Director of Parts and Accessory Sales
Warranty and Technical Support
Hobie Cat USA
(Retired 11/7/2022)

Makes perfect sense to me. So, is there a permanent gel-coat seal that is applied on top of the gel coat at the factory when new? Or does the gel coat itself form a natural surface seal when applied, ( which is then breached when cut down later during a clean-up like mine? )

If a new permanent seal must be established, does anyone know what it is, and how it is applied?

Thanks,


Dan

It's technically known as a 'resin rich film' that floats to the surface in the mold when boats are built. Due to the fact that your boat sat in the sun for some years could contribute to the breakdown of this layer, it can also happen if a previous owner wetsanded the hulls for a 'racing bottom'. I get a check every month for my monohull from Duke Energy. It turns out that the acidic stuff that comes out of their stacks kills gelcoat. Was your boat stored by a power plant?

I wouldn't worry too much about a respray or or anything like that. As someone else said teflon wax usually will seal it up. In extreme cases, such as wet sanded bottoms, a hard type carnuba wax may be needed. What kind of wax did Elkhorn send you off with?

I looked into color restoring wax to see how, if one used it, it could 'wash off'. It can't. Usually they are a fine buffing compound on the line of a 'swirl mark remover' like 3m perfectit I.

I spoke with Elkhorn Composites today regarding your dilema and he said he buffed it like he does all of the other boats that come through his shop, and it left looking pristine. Buffing a boat cannot 'wash off'. It's either buffed or not, so there can't be any 'missed steps' in the process. After buffing a boat I generally don't even wax it. I leave it up to the owner, because some people prefer a non waxed boat. In your case I would wax it.

One quick question: Was there a bunch of extra junk in the water the day that you sailed?

Wax it and get back to us. I'm sure it will fix your problem.

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Thanks for the thoughtful post Jeremy.

I'll try waxing it, but first I'll need to cut the new staining. Note: I bought some West-Marine PTEF, and Elkhorn gave me some oxalic acid when I picked up the boat.

While I will try waxing, I am not optimistic, as Elkhorn delivered it waxed; I was clearly told that. (Also, when I spoke to Elkhorn about this problem he did not ask me if I had remembered to wax it, or how I waxed it.) He had obviously waxed it, and was totally puzzled as to what may be causing this.

He did send me home with a half a bottle of the wax he used, which was Scotchgard Marine Liquid Wax (3M part number 09061).

I do agree that failure to wax after cutting/buffing would probably explain the rapid return of the staining - but it's not Elkhorn's style to forget or skimp. We've got a mystery. Sail #1 after the clean-up was super low tide, dark and stinky. The SF bay can be really lame; but why only to my boat?

Regarding wet-sanding and sun damage: Compared to most Hobies out there, this one, an 03, is a baby - and I have kept it fully covered for the past two years. From what I have gathered, Hobies need more time than that to foul-out due to the sun. In addition, you know Rudy, the guy I bought it from; he took good care of it, kept it bone stock, funky plastic rudders and all; wet-sanding for speed is highly unlikely. However, Rudy was particular about his stuff and may have had it buffed too often or used harmful chemicals on areas that got chalky due to the sun. In further rebuttal to the sun-damage argument, he stored it in the same spot his entire ownership; the sun is unlikely to inflict such a uniform 360 degrees of damage. If the sun could do that, then the north side of trees would have no moss! My logic above says forget about sun damage, but why are the hulls so clean and nice under the trampoline???

I truly appreciate the help and thoughts in sleuthing this problem. I will be trying some of these solutions tomorrow.

Thanks,

Dan
Campbell, CA
03 HC17 SE

Wax is not the answer my friends. It will eventually wear off (sooner than you think!), and your brown stains will return.

Clean the boat with some sort of oxalic acid (Walmart's "Hull Cleaner" will do just fine). The oxalic acid will neutralize the tannins (aka bleach) and your hull will return to white.
Order some of Holmenkol's "hull polish," which will seal the gelcoat on your boat and prevent the stains from returning for a long time.
McLube will also have a similar (but much better) product out in the coming weeks.

Wax won't solve the problem for very long, but sealing the gelcoat will.

Right Dave Lennard?

_________________
Trey Brown
www.velocitysailing.com
2006 N20 1017
1998 H16 102698
www.sunjammers.com ftw!

What about 303 protectant?

Use over a teflon or carnuba product, or in place of?

_________________
Sheet In...Max Out
www.fleet297.org
sailflatlands at gmail dot com

Those of you (Trey & cw) who suggested that the staining would respond to oxalic acid were right on! It was a zero-effort, instantaneous affair! Mere contact with it removed the staining, where waxing over it just made it a shiny stain. And rubbing with a mild wax/cleaner had only a minor effect.

I created test and control zones on the hulls with combinations of oxalic acid, wax, ptfe etc... Now I've got to get out on the water a bunch of times to see the results. I'll keep you posted.

Trey, I am interested in the sealing products you mentioned. Any suggestions on where to buy it? And what is the detailed scoop on the Mclube product you alluded to?

Peace,

Danny
Campbell, CA
03 H17 SE

Call Mike @ Layline: 1800-542-5463 and he'll set you up with the Holmenkol product. It's very easy to apply and lasts a good long while. Be ready though, it's not cheap...

BUT

I'd personally wait until the beginning of May when McLube's new product will be available. Email me and I'll fill you on some details.

velocitytrey *at* gmail.com

_________________
Trey Brown
www.velocitysailing.com
2006 N20 1017
1998 H16 102698
www.sunjammers.com ftw!

Yes Trey you are so right. You have come such a long way and I am so proud.

Dave, I know you aren't much of a drinker, but that sounds like a drunk post. You'd better not try to hug me at the next regatta or Renee will think something's up with you...

_________________
Trey Brown
www.velocitysailing.com
2006 N20 1017
1998 H16 102698
www.sunjammers.com ftw!