Fairing in prep for paint.

Yes, it has been a while since this blog was updated, but I have been suffering through the hell of fairing the boat and didn't really want to talk about it. Now it's all shiny and the plastic tent is gone and my shop is no longer a dusty pit. I still have to paint the boat, but that seems like less of a chore than fairing.

Many parts of the boat had fairly even gelcoat application and the boat was quite fair to begin with, so it could have been much harder. Areas where gelcoat spraying was difficult, the gelcoat was applied with a brush. When it was removed, it left deep ridges and valleys that needed to be filled and sanded multiple times. The cockpit, both sides of the seat backs and aft crossarm were really a chore to fair. The tan and reddish colors in the photo below are areas filled with microlight or low-density fillers.

The fairing started with some careful selective filling along the waterline and where the gelcoat was left under the wing.  

The light shining under the batten edge shows how thick the gelcoat is.

The copper color in the lower part of the photo is the copper/epoxy bottom that was applied in the mold. The light shining through is where the gelcoat used to be. 

Both of these areas had to be carefully filled before applying a thickened coat of epoxy to the surfaces of the hulls.

The gelcoat was faired in with my long, strait, and sharp edged application tool.

This step was done before filling the uneven edge at the waterline.

The waterline (all 105 or so feet of it) was faired in using a wide putty knife, applying pressure only to the edges of the knife.

A heavy "fill coat" was applied to the lower topsides over the still-tacky waterline filler.


All surfaces that had had the gelcoat stripped were thoroughly sanded and fill coated with epoxy and 410 Microlight filler mixed in at almost 50 percent by volume.
The fill coat was applied with a short (1/4") nap roller.
The nap roller will spread the thick fill coat mix out evenly (with lots of rolling), something that a foam roller can't do.

I used good quality rollers for applying the fill coat. A 9" roller cut in half worked well and was more economical as the rollers soak up a large amount of epoxy.

The fairing process was not pretty and not at all photogenic, I used mostly longboards with 80 and 100 grit for fairing and smaller plywood sanding blocks of varying thickness and stiffness for fairing really curved areas.
The method of rolling on a thick fill coat worked beautifully. The 410 microlight filler combined with WEST 207 hardener made for a fill coat that was both thick and easy to sand. This combination of ingredients seems to somehow flow out fairly smooth, even though it is applied thickly with a nap roller.

When fairing, the low spots remain easily visible as they are semi-glossy (unlike when fairing high-build primer). Low spots were filled and the surfaces sanded again.
I used multiple different knifes for applying thickened epoxy to low areas, from a 12" wide drywall knife to a 3" wide thin putty knife. All knives had sharp & straight edges.

Early on I realized that for me to get the boat sailing, I needed to lower my standards. I skipped steps that really should have been done to make the surfaces more fair or more ready for paint. That being said, what I did was pretty efficient time-wise.

I rolled (and tipped with wide foam brushes) a coat of 105/207 over the entire boat after fairing and this coat will be lightly sanded before paint. No primer will be used.

A gloss coat of epoxy has many advantages over epoxy primer. It "flows out" to make a smoother membrane and because it is glossy, you can see imperfections that may need more work before painting. Most epoxy primers stink for days after application and, while primer is softer for sanding, one is sure to sand through it in places, so there is no solid color advantage to using primer. Primer is also softer that two-part paints, so using epoxy instead of primer may make for a tougher paint job.

Like sanding the fill coat, sanding the glossy epoxy coat is made easier because it is glossy. It's easy to sand just enough for the glossy spots to disappear, without sanding through the gloss coat.
I had some seams in the gloss coat (because I broke the surface into different sections for coating) and even though I tried to thin the coating at these taped edges, the seams were still difficult to sand flat.
I use a thin flexible fiberglass plate sanding block for areas like this, using 220 grit sandpaper, which is appropriate for 2-part paints (photo below).

Most finish sanding is done with  a random-orbit sander. For edges and corners, a hard rubber sanding block and a foam rubber sanding block, all with 220 grit. Remaining glossy spots are hit quickly with a 3-M abrasive pad.

I have finally started painting and it is going well, even with two large exhaust fans pulling dust through my shop. Better some dust in the paint than to absorb nasty fumes.

We are taking painting photos in order to update our book "Rolling perfection", an e-book we sell about using Interlux "Perfection", a two-part LP paint.

I built a honeycomb & fiberglass hatch for the cabin. It's compound curved to fit the cabin and has a gasket notch machined into the edge.

The hatch is made from honeycomb with fiberglass skins so that it can let light into the cabin.
My previous boat had a honeycomb and glass companionway drop board and the light it let in was not only welcome but quite beautiful as well. Hard to show in a photo...

The hinges were made in a long blank from G-10 plate and G-10 tubing that were glued together before bagging carbon over the length of the blank.
I took careful photos of building the hatch and hinges and may do a blog post about it if there's interest.

The molded in rudder gudgeons had carbon reinforcement (this was visible without the gelcoat), but I did some reinforcement and clean-up anyway.
The holes for the pin were a bit sloppy, but it was super easy to remedy that, thanks to aluminum's thermal expansion.
The holes were drilled out to a larger diameter and opened up a bit at the upper ends to allow epoxy to enter. 3/8" hardware store aluminum tubing was waxed and inserted. Vacuum bagging mastic was used to seal the lower ends of the holes as shown before heating both upper and lower gudgeons with drop lights.  Epoxy was syringed in and because of the temperature, quickly flowed in to fill the void around the tube.
The drop lights were kept aimed at the gudgeons until the epoxy had fully cured. After cooling, the aluminum tubes pulled out easily by hand.