Treadmaster, small cracks in deck

[megalops]

Hey all,

At some point in her sort of recent life the decks on my 36' gulfstar trawler (insert powerboat insult here) were recored with some sort of foam, then covered in treadmaster. For the most part they have held up well, no evidence of rot, one place where the top sking has not ahered real well. But now, the treadmaster is pretty much shot and the decks look pretty rough.

I'm going to peel off the treadmaster and replace it with sea dek, http://www.seadek.com/, a product I use in a commercial way on my flats boat and have had good luck with. I plan to sand the decks under the treadmaster after it is off and then wipe them down with alcohol. I have a few questions though.

1. There are some hairline cracks in my decks, no water seems to be getting through them, but they don't look pretty. How should I repair them? Can I just open them up with my dremel and fill them with thickend epoxy?

2. Should I drill down into my deck core in a few places to see how it is holding up? I'll be recovering them, so all I would have to do is fill the holes with epoxy.

3. There is an unused deck fill that I would like to remove. There is no access to the underside of it. I can get it out, but how do i fill it without being able to tape up the backside? Again, it doesn't have to be pretty, the sea dek will cover it.

4. The sea dek goes on in pieces, you don't mate the edges but rather leave a gap of a couple of inches. I want to paint these gaps, Should I paint them before I lay down the sea dek and risk poor adhesion, or lay the sea dek and then tape it off and paint after it is down?

Thanks,
Doug

[mitiempo]

Hi
You're forgiven for having a powerboat.
As far as the hairline cracks, I would do as you suggest and grind them open and fill with thickened epoxy and sand flush as you're going to cover them anyway.
I would try and see if the deck core is compromised either by tapping the deck and listening for a dull thud as opposed to the solid sound you get when the deck is good, or alternatively you could buy or borrow a moisture meter and check it with that. Less messy than drilling holes. If you find a suspect section that could be drilled to confirm.
The unused deck fill hole can be repaired without bottom access. The West Fibreglass Repair Manual details this in section 4 & 5.
Here's the link to the full manual.
http://www.westsystem.com/ss/assets/How ... enance.pdf
It's now free - I had to buy mine but that was before the internet.
As far as painting the gaps between the new deck pieces, I was on the sea dek site and couldn't easily find an installation manual. If you have this it should detail surface prep. Does it adhere well to previously painted surfaces? If so, paint before application following their recommended procedure.
I hope this has been of some help.
Brian

[Tim]

At some point in her sort of recent life the decks on my 36' gulfstar trawler (insert powerboat insult here) were recored with some sort of foam, then covered in treadmaster. For the most part they have held up well, no evidence of rot, one place where the top sking has not ahered real well...

1. There are some hairline cracks in my decks, no water seems to be getting through them, but they don't look pretty. How should I repair them? Can I just open them up with my dremel and fill them with thickend epoxy?

2. Should I drill down into my deck core in a few places to see how it is holding up? I'll be recovering them, so all I would have to do is fill the holes with epoxy...

When the boat was recored previously, did the installer re-use the original top skin panels? If so, the cracks you are seeing are quite possibly left over from the flexing the decks must have done before the recore was completed, though if this is true one wonders why anyone would reuse the old skins for new work. How significant are these cracks? Will they transfer through the Sea-Dek product if left alone? The cracks could also point to poor bonding of the core to the top skin, and possibly other problems. More information is needed to determine the cause of these cracks.

If the cracks are widespread, and more significant than not, you might consider applying a single layer of lightweight (say, 10 oz) cloth over the entire deck surface before you repaint and apply the Sea-Dek. Grinding out cracks with a small tool will not only test your patience and waste your time, but is also of limited effectiveness in the long run, in anything by the smallest areas. Of course, installing the cloth is not an insignificant job, but if the cracking is widespread enough, it may be your best option to contain it and prevent it from reoccurring through your new top surface. I don't have enough information to know whether or not you need to consider this option or not.

I would absolutely take this opportunity to drill a number of holes through your top skin and into the core to inspect the core, and also the bonding of the skin with the core. Before doing so, sound the decks with a steel hammer. If you don't know what to listen for, then find someone who does, or hire a surveyor to look at the decks only. The sounding, to a knowledgeable ear, will help you locate any areas where you might want to inspect further by drilling. You've already intimated that the top skin isn't well-adhered in one or more places, and other things that point to a less-than-perfect job. It's easy to fill these inspection holes, and you might as well find out now whether the recore job is worthy or not. Any significant voids or improper bonding between top skin and core will lead to flexing and cracking over time, and possibly other problems, some of which may have already manifested themselves, from the sound of things.

[megalops]

OK, sorry for the long delay. Here are pics of the cracks that I want to repair. The one with my ugly foot in it is the worst one. The foot is to give perspective of size.

Thanks for any advice.

Doug

[megalops]

Sorry for attachments, just learning how to post pics to this site. Here is another one.

[megalops]

And the third.

[Rachel]

On the long, straight cracks - since you mentioned that the deck of your boat had been recored, I wonder if perhaps someone re-used the original deck panels but then didn't grind a relief and fiberglass tape the joints? It almost looks as though someone put the panels back on, faired, and then painted (?)

Rachel

[megalops]

Good possibilty Rachel, as there is no sag on that side deck and when the boat was surveyed the surveyer sounded that area and found no evidence of rot.

So you think the best thing to do would to be to grind a bevel into that crack and build it up with cloth? Then paint and put the new Sea Dek over it?

[Rachel]

I think I would want to sand/grind that area to see what is going on there for sure, and then proceed accordingly. If the joints aren't fiberglassed, then grinding/glassing sounds reasonable; just that since you have to grind anyway, let's see what you've got under there.

Rachel

[megalops]

OK, I have the old treadmaster sheets off, they were secured to the deck with some sort of caulk type adhesive. The adhesive is still gooey and a little sticky, but in bad shape. I can get most of it off using a heat gun and a scraper but not all of it, it was quite labor intensive and I have a lot of deck to do. Any suggestions on how to get the rest off?

I tried alcholol, then mineral spirts, with not much success, haven't tried acetone yet.

A dock neighbor suggested using a bronze brush on my angle grinder, but that seems really aggressive.

How about a large grit pad on my sander?

Thoughts?

[3wtk]

HD sells a product to clean up adhesive used for laying vinyl tile or laminate flooring. Might work.

[georgefmys]

For easy adhesive or sealant removal, try 3M adhesive cleaner-it comes in liquid or aerosol. For your use, the liquid,liberally brushed on with a cheap bristle brush is the way to go. If you saturate a couple sq. foot area at a time thenwork a sharp-edged drywall knife under it, the goo should come off really cleanly. This also seems to help dry out most adhesives, making it easier to sand off any residue without clogging the sandpaper.

[megalops]

OK, isn't it great when you stumble on a tool that makes a really hard job easier? That is what I did today.

Nothing has helped with the adhesive, I tried the 3M adhesive remover, and it had no effect, even undiluted.

I'm pretty sure now that the adhesive the PO used is Life Caulk, though in some areas it looks like 4200 or maybe 5200. Under some panels it is layed on as much as 1/4 inch thick. In the areas where it is really thick I'm having to cut the treadmaster sheets away with a razor knife, like filleting a fish. Quite tedious.

So I tried hitting the leftover adhesive with my sander and my last 80 grit disk, it worked OK, but gummed up quickly, so I headed for the local hardware store (only store there is in Carrabelle) and found this:

http://www.wagnerspraytech.com/portal/p ... 2C747.html

I just bought the disk, it screwed right onto my angle grinder. It chews right through the adhesive. Only problem is the disks, though long lasting are $17.00 each. Ouch.

[Rachel]

Nice find. I like the name, too: "PaintEater" Sounds hungry.