Finishing Off Fiberglassed Decks

[Tim Ford]

I think there is a little on this subject dispersed throughout other threads, but I thought we could get an authoritative, comprehensive discussion going under its own title. (okay, authoritative and comprehensive may be a lot to ask for, but in lieu of that.... )

I'm getting close to having my decks done and was looking for some ideas on what to use from glass to final paint stage.

Chad, I saw on your blog the bit about phenolic microballoons and it looks like you've used the MAS balloons (from the color). Did you mix them with West105/205? I don't know why West would make any difference but that's what I'm using. Only if one is denser than the other. I like the thick consistency of the stuff you laid down, though.

Once you sand down the microballoon coat, what are you thinking about for your next layer? I was going to finish up the quart of Interlux PrimeKote and then see how that worked before ordering anything else.

[Chad]

I don't mind using the West Microlight under the glass- it isn't any softer than the wood that it is covering. I think it is too soft to go over the glass though, where it will be subject to direct impact and abuse.

I've started using Raka epoxy ($168 for a 3 gallon kit) for these large-dose glassing and filling steps. Their slow stuff gives one to two hours of open time, depending on the shop temp. The epoxy is runnier, which means it accepts a much higher loading of filler to reach the desired consistency, compared to West resin. Less resin, more filler is more economical and sands faster, too. And the stuff doesn't blush, despite what _Vegas_ and epoxymoron say on SA. I think I bought those phenolic balloons from Raka as well- the color is partially because I've added a little tint to to the epoxy, to differentiate it from the next layer(s).

I still have my cans of West System for jobs that I want to cure more quickly. I have also used Gougeon's Proset for some carbon projects, and that stuff is around 25% more than West, and lots runnier which is nice for laminating. It has some unique curing properties which make it useful in niche situations, but the cheaper stuff has met my needs lately.

I'm a firm believer in using as much filler as the application permits- for trowelling on I go a ways beyond "stiff peaks" until the stuff starts breaking my stir sticks! For the skim coat, I used something like mayonnaise, so that a chip brush could spread it around sorta evenly (I cut the bristles to half-lenght first). Then sand off (with a longboard- no palm sanders or DA's) as much of the stuff as you can, until you're just getting into the glass (cutting halfway or so through the overlaps), or turning the filler translucent. Then spot spackle with a very thick mixture, and sand, and repeat...

I have some of Interlux's Primekote (the 2-part stuff that kills ya unless you use a respirator, not the one-part "Pre-Kote"). I've used it for the keel, another boat's rudder, and some other boat projects- it's really good stuff. It's what I'll use, once I have my deck sorted, right before I flip the boat. If you plan to use 2-part paint eventually (Awlgrip/craft or Perfection), you'd be silly to use the one part primer.

Not authoritative or comprehensive, but that's my take...

[Kevin]

I did the following and it worked ok for me.

Filled the weave of the cloth with a 2nd coat of epoxy. Still not smooth but didn't worry cause there was more to add.
Used micro balloons in a pretty think mix (probably not as thick as Chad described but I did break my fair share of stir sticks) to finish filling the weave and create a base coat for fairing.
Sand until you hit glass.
Rough up low areas.
Apply more micro balloons, sand, rinse and repeat.

Once fair and happy I used interlux e2000 2 part primer. This is an epoxy based primer and it requires a respirator (just buy one and use it). The e2000 filled the tiny pin holes left by the balloons that were cut in 1/2 during sanding very nicely. I applied 3 coats and I tinted the last 2 so I could see that I wasn't going through the base coat.

I bought balloons and "fairing compound", which contains balloons and other stuff, from US Composites in Florida.

IMHO, the hardest part is roughing up those lame low spots. Just the feel and the sound of that 60 grit just killed me. Like finger nails on a chalk board to me.

Kevin.

[jray]

I did the deck almost the same as Kevin, after glassing I applied two flow coats of epoxy then sanded and followed up with micro balloons and epoxy mix for those pesky lows. I did spend lots of time fairing before laying the glass so fairing afterward was minimal. As with every part of this build there are lots of ways to get things done. I agree, use the best primer whichever companies product you decide to go with. I primered several coats sanding between before flipping to the bottom. I finished the topcoat on the deck and cockpit after the hull was complete.

[ryderp]

I'm planning on priming the bottom this weekend. I'm working to fill in the divots and low spots, but I assume that there will be some spots that I just didn't see before applying the paint. What is the best filler to use on top of the primer?

Phil

[Chad]

The same stuff as used under the primer is fine- Microlight or phenolic balloons and epoxy.

[micah202]

The same stuff as used under the primer is fine- Microlight or phenolic balloons and epoxy.

..or use a simple bondo mix for pinholes,,there's a specific fine formulation for pin-hole filling available at autobody supply shops......this has the benefit of setting quick so you can get-on with sanding.

..interestingly,,bondo products actually do cure against epoxy products,,where other polyester products don't.
...the bond is mechanical ,not molecular,,,so this practice is recommended for pinholes and small stuff only

...in 'industrial' settings an automotive pinhole filler 'mirroglaze' is used,,but it's sooo soft that you have to take care what solvent wash you use before spray,,or the mirroglaze can be dissolved

...with an epoxy-based filler,as hard or harder than the primer when cured,it's likely in sanding the surface you'll take down the surrounding area more than optimal

[Kevin]

I'd recommend against using bondo on a boat. For pin holes the primer should have filled them nicely. That was my experience anyway. I'm assuming we are talking about those pesky 1/2 balloons that my sand paper opened up and the like. Bigger than that and it's not a "pin" hole (imho of course).

If you used a 2 part epoxy type primer you can just use more epoxy with filler. I would rough sand with 60 grit (for the mechanical bond you need), fill, sand and then prime over it as a way to get the best end result.

Kevin.

p.s. Keep in mind that this is the deck that you are just going to screw up as soon as you start sailing the boat and moving/tweaking things. Especially true if you plan to put non-skid down in the specific area.

[micah202]

I'd recommend against using bondo on a boat. .

..yeh,,it may seem strange,,but as a pinhole filler,it's quite acceptable in the marine industry

[slowpoke]

They recommend you don't use bondo below the water line on a boat that will stay in the water for long periods. The filler in bondo is talc, and it will absorb water. That said, I used bondo on the bow of my old cal 27 about 8 inches above the waterline, and the repair has lasted since 1998, with the boat in the water year round. I did use a good quality spray paint (rustoleum) to seal it though, so maybe that was what saved it.

Ignorance really is bliss!!!

[Tim Ford]

Persistence pays off...but that's a whole lot of persistence. Ran out of 407 unfortunately, or I'd be close to flippin'.

[jray]

Looking great Tim! Just a warning, the boat gets much bigger after you get her flipped.

[Tim Ford]

Yah, I was sorta figuring it would, but (and maybe I'm being naive, here) I think the worst is over. The decks and cockpit of #87 have so many complex curves and radius bends that I figure the bottom & topsides are going to be a walk in the park. Big flat areas I can deal with...it's these curvy corners and stuff that is eating up the time. Why oh why did I ever depart from that simple, easy, building plan? Woe is me, oh, wooooooeeee is me.

[Chad]

Looking great Tim! Just a warning, the boat gets much bigger after you get her flipped.

Yup! Ain't that the truth. Can't easily reach the middle, gotta climb on top, wore holes in my knees sanding while kneeling, little spots of blood all over! Taking the weekend off while the glass cures...

[M&S]

Beautiful job Tim.

[Shazza 273]

Yah, I was sorta figuring it would, but (and maybe I'm being naive, here) I think the worst is over. The decks and cockpit of #87 have so many complex curves and radius bends that I figure the bottom & topsides are going to be a walk in the park. Big flat areas I can deal with...it's these curvy corners and stuff that is eating up the time. Why oh why did I ever depart from that simple, easy, building plan? Woe is me, oh, wooooooeeee is me.

Well worth the effort by the looks of it to me Tim, looks fantastic and it's all down hill from here

[slowpoke]

I knew that if I looked in here somewhere I'd find a thread that covered the area I needed help in, and sure enough, here it is!

[admin]

Glad to hear you are there! I'm getting close to the re-flip, so hopefully there will be more content coming! Just needs to warm up a bit...like 30 - 40 degrees.

[slowpoke]

I know what you mean, I've been having to wait 2 or 3 days for my fairing compound to get hard enough to sand! not enough time during the day over 50 Degrees F to get a continuous cure. I plan on doing like Chad did and wrapping in black plastic to cook the boat soon!

[micah202]

I know what you mean, I've been having to wait 2 or 3 days for my fairing compound to get hard enough to sand! not enough time during the day over 50 Degrees F to get a continuous cure. I plan on doing like Chad did and wrapping in black plastic to cook the boat soon!

...not t'mention all the moisture that flows through TJ this time of year!

[admin]

bit of a hijack here, but nice "fix" on the SA forum! Thanks for that!!

[Tim Ford]

ALright, next question:

I have two coasts of Prime-Kote down on the decks and cockpit sole and bensons. I want to use Kiwi-grip in areas (a lot of areas) much like Jerome did on hull 270 (see: http://i550-hull270.blogspot.com/ - scroll down to Sept 20, 2011). Should I paint the entire thing in Perfection® (which would be easier) and then tape and scuff the Perfection in preparation for the KIwi? Or should I mask (tape out and cover) the areas I want to Kiwi, apply the Perfection® around these areas, and then remove the masked areas and apply the Kiwi DIRECTLY to the Prime-Kote (instead of painting the Kiwi on top of the Perfection®) ???

[micah202]

ALright, next question:

I have two coasts of Prime-Kote down on the decks and cockpit sole and bensons. I want to use Kiwi-grip in areas (a lot of areas) much like Jerome did on hull 270 (see: http://i550-hull270.blogspot.com/ - scroll down to Sept 20, 2011). Should I paint the entire thing in Perfection® (which would be easier) and then tape and scuff the Perfection in preparation for the KIwi? Or should I mask (tape out and cover) the areas I want to Kiwi, apply the Perfection® around these areas, and then remove the masked areas and apply the Kiwi DIRECTLY to the Prime-Kote (instead of painting the Kiwi on top of the Perfection®) ???

...I'm not familiar with the 2 products,,but if kiwigrip is a 2part paint,,and Perfection is a non-catalised enamel,as I think they are(?),,you should definitely NOT try to paint 2 part over enamel. ....if it's 1part on 1 part,,,or 2 on 2,,,I'd do a test patch,,,but yer should be okay

[Chad]

Perfection is 2-part, Kiwigrip is 1-part.

Kiwi will go over both the primer and the paint. Draw some rough non-skid shapes on the deck with pencil, and apply your paint so it slightly (1-2") overlaps your planned non-skid areas. This leaves you spots to stand in the boat while applying the paint. Afterword, clean those spots and prep per Kiwi recs.

(Or use Hydroturf, and keep your knee skin)

[micah202]

...thanks for the correction Chad,,,I wouldn't worry about a 1 part over a 2 part