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Painting the Hull
This page was last updated on 14 November 2008.

Hull Preparation  |  Priming  |  Topcoats  |  Boottop  |  Bottom

Safety Considerations  |  Awlgrip Tips

Primer

The first step before painting was to tape off the outside of the mahogany toerail; I didn't bother taping off the bottom of the topsides at the scribed waterlines, since this area will eventually be sanded and covered with bottom paint, and since I was using expensive tape I chose not to waste it there.

I primed the hull in the same operation as priming the decks, but did the topcoats in separate operations.  However, priming was a very nice thing to get out of the way.  On the large surfaces of the hull, I used a 3/16" nap Glasskoter roller to spread the primer, then tipped it off with a brush.  This left brush marks that did not level out, but I was prepared for this since I had used the product before.  (More description on the product on the deck painting page.)  I started at the stern on one side and worked my way forward, rolling about a 1-2' longitudinal area from rail to waterline, then tipping it off and moving on.  I only painted just past the top scribed line, which used to indicate the top of the boottop, since I plan on raising the bottom paint to this line and striking a new boottop above.  I moved quickly to avoid serious lap marks, since the primer dries very quickly.  However, significant sanding will be necessary anyway, so I wasn't too worried, and there was nothing I could do about it anyway.  I was also at a disadvantage since the staging was set up for deck work, meaning I had to sit on the staging to be at the proper height to work on the hull; when the decks are done, I will lower the staging to make application of the Awlgrip on the hull much easier.  This will be done in a separate operation from the deck topcoat painting.

The primer on the hull came out really poorly.  The brush marks were very difficult to sand out, and were so deep that I ended up sanding through the primer over much of the hull, probably 50% or more.  This was unsatisfactory!  Tipping just does not work well with this particular product. (Awl-Quik epoxy primer, # D-8003; Converter # D-9001) 

I spent several difficult hours sanding the hull primer, at first attempting to maintain a decent coating by sanding with 220 grit and then, after about 1/3 of one side, I decided that there was no point--the brush marks were just too deep, and there was no avoiding sanding through.  This was very discouraging and, to top things off, the primer apparently becomes more difficult to sand the longer it cures.  When sanding the deck, the day after priming, I was able to easily hand sand.  The next day, however, it was next to impossible to easily sand the hull!  I ended up switching to 120 grit for the bulk of the sanding, then finishing with 220.  All in all, a very aggravating day.

I decided to reprime, although this time I would not tip off the primer after rolling it on.  I rolled on two coats, allowing about four hours between coats, and the initial results appear to be much better.  There is roller stipple, of course, but the 1/8" nap mohair rollers leave a fairly smooth surface, and it looks like it should sand smooth without too much trouble.  


Update:  2008
I chose the Awl-Quik primer for this job originally because the information source I had at the time indicated that this was the choice for brushable primer within the Awl-Grip system.  Clearly, this source left something to be desired, and perhaps even more clearly I learned much from this experience and others throughout the years following this job, which led me to an improved understanding of these paint systems and their application.

Here are the hard facts regarding high-build primers like Awl-Quik:  they simply do not self-level the way that the much thinner finish primers so (Awl-grip 545, for example, or Alexseal 442 finish primer).  Even when applied with spray equipment and substantially thinned, the very nature of high-build primers is to be heavy and thick; it helps to think of high-build more as a sprayable fine filler than as a primer.  I believe that high-build primers are useful and virtually required on older boats when attempting to achieve a fine finish.

Additionally, high-build primers are not meant, nor ideal, for use as the final primer before applying LPU topcoats (Awl-Grip or Alexseal).  They are intended to be covered with finish primer in order to provide the smoothest and optimal base for the thin, glossy topcoats.

This combination of factors led to some less-than-ideal characteristics in my final paint job, which I originally applied in September 2000.  While I was extremely pleased with the quality of the job overall, particularly when compared with how the boat looked to begin with, it was a learning experience, and the finish was not as good as it could have been.  I blame this largely on the primer because using the application techniques I had at the time, it was simply not possible (lacking a potentially ridiculous buildup of coats for which I had neither time, inclination, nor material) to perfectly sand the Awl-Quik to the surface required for topcoat substrate. 

In trying to avoid sanding through the primer whilst smoothing it, I erred on the side of caution and sanded less, rather than more.  While this approach would have been sufficient for normal paints, high-quality, super high-gloss LPU paint simply requires something better.  As a result, there was some stipple remaining from the roller primer application--as well as brush marks from the failed roll-and-tip primer application before--that ended up transferring through the topcoats.  This texture was so minor as to be nearly unnoticeable when I completed the primer sanding, but the unforgiving nature of the topcoat simply couldn't and didn't hide it.

Admittedly, I am being very critical of my earlier work in this update.  In general, my original paint job was better than fair, and perhaps even approaching very good.  Experience gained in the years hence simply caused me to turn a more critical eye on the paint as time went by.

All these factors, combined with a desire to do better, refresh the appearance of the boat, and to finally repair, in a proper manner, some earlier hull damage (at the bow) and the usual collection of minor docking scars, led me to the decision to repaint the hull during the fall of 2008. 

You can read more about the hull preparations and new paint in the 2008 winter refit logs.


Topcoats

The next day, following the multiple rolled-only application of Awl-Quik primer, I spent about three hours sanding the hull with 220 grit.  The coverage was much better than it had been before, although still not perfect; I believe that four coats or more of the primer, applied with the roller and thinned appropriately, may be desirable to ensure a thick enough coat.  However, I has a thin, constant coat over the hull at this point, with only a few breaks, and I intended to call it good.  The primer was difficult and messy (dusty!) to sand, and, having done the entire hull twice (four coats) I was not about to do it again.  Overall, it looked good and was a sufficient base for the Awlgrip.  Please note the observations in my 2008 update just above.

With the Awlgrip on the deck done, I lowered my rickety staging several feet to give me a better position for painting the hull.  Then I applied the first coat of Flag Blue Awlgrip, # 5002.  I mixed it the same way I did with the deck paint, but my application was different.  On the large hull surfaces, I used a Corona Glasskoter 3/16" nap  mohair roller on a 7" frame to spread the paint evenly, then tipped it off with a 3" West Marine Flagship badger brush.  On this coat, I tipped the paint in a vertical direction--that is, brushing from the toerail to the boottop.  This is generally the recommended method, but I thought I might try horizontal brushing on the next coat--not for any particular reason, but the very top, beneath the toerail (with my non-standard mahogany rail, that is) needs to he horizontally brushed to properly smooth the paint and avoid runs.  It might make a better, smoother job if the whole area was brushed in the same direction...time will tell, maybe.

Anyway, the first coat went on pretty well--it's only the first coat, after all, so it doesn't have to be perfect.  The dark blue did not cover the off white primer particularly well, so plenty of white still showed through.  However, the blue transformed the boat, and it is going to look great when three coats have been applied!  Even though it is the first coat, there is still good gloss (see the yellow top step of the ladder reflected?) and looks better than the boat ever has since we have owned her.

The next day, I was able to sand the first coat.  I used 320 grit sandpaper to lightly scuff the entire area, taking extra time to sand away any bugs or runs that were in the first coat.  I sanded entirely by hand, since an attempt to use my palm sander removed entirely too much paint.  The surface sanded easily by hand and took about 2 hours to sand the entire hull in this manner.


I applied the second coat much like the first (after vacuuming, solvent washing and tacking off the surface), although this one was much more satisfying.  Immediately, the true color came out, since it covered so much better over an existing coat.  I ended up tipping the paint off in a vertical direction once again, as this seemed to work the best--despite my thoughts above.  I started by painting the transom, rolling on an even coat over half at a time and tipping vertically.  I also painted the corners of the transom so that when I painted the last corner of the hull later I wouldn't have to worry about slopping any paint onto the by-then-tacky transom.  Next, I moved on to the port side, beginning at the counter and painting up to the ridge in the centerline.  This is the perfect place to begin, since, with the ridge, there will be no lap marks here when I paint the other side an hour or two after beginning the other side.  Even if there were to be a lap, this is a very inconspicuous place.  I painted the entire hard-to-reach area beneath the counter and partway up the hull before moving up onto the staging to continue.

I moved forward on the port side, painting about 2-3 linear feet from gunwale to waterline, then tipping off before moving on.  This effectively maintains a wet edge.  I was very careful at the transom corner not to create a drip or otherwise compromise the paint already on the transom.  It is also important to be careful of starting a drip at the gunwale.  After bushing each area, first from the waterline upwards, then finishing from the gunwale downwards, I brushed a horizontal brush width immediately beneath my overhanging toerail to finish off the area.

Working around the bow required some quick movement and careful brushing, to maintain the wet edge, cover all surfaces and avoid messing up the nearby paint, but soon I was past the bow and working back down the starboard side towards the stern again.  I had to add more reducer to the paint several times as I went along, as it became slightly more difficult to brush; the extra thinner made things much easier again, ensuring that the paint would flow out properly.  I finished up where I started beneath the counter.  Total time:  about 1 1/2 - 2 hours.

After the second coat, the hull looked great, but there were still a few areas where the white beneath showed through, especially in direct sunlight.  Therefore, I applied a third--and final--coat a day after the second, following the same procedure.
 

I was pleased with the painting results.  The hull looked great, and was extremely glossy and smooth--it looked like the paint was still wet even when it is dry.  I don't think this sort of lasting gloss can be obtained with anything but a high quality liner polyurethane paint system like Awlgrip, and it should last for 10 years or more with little appreciable deterioration--barring some unforeseen circumstance.  I think the extra cost is worth it.

Flaws?  Ok, there are some.  Are they noticeable to anyone but me?  No.  There are one or two small drips that will be impossible to see once the boat is in the water, and a few areas where bugs got into the wet paint; removing them after the paint dried left only very small marks that will be invisible to anyone.  Who knows, I may even lose track of where these flaws are--and believe me, right now I know where they all are!  Despite a part of me that is tempted to sand and repaint one more time, I think I have gotten the best finish I realistically could under the conditions--that is to say, it is about  95%, and equally as good as many professionally sprayed boats I have seen.  Of course, I have seen flawless pro jobs, but I can't complain at my own results.  As far as being able to tell is was brushed instead of sprayed, you can't--except for the lack of orange peel that you might see in a spray job.
 

In the photos, the blue paint is brought to the top scribed boottop line; the bottom paint will be brought up to this line, and the new boottop will be struck above, covering over the bottom portion of the blue.

 

 

 

 

My reflection in the hull as I take a photo from a few feet away...

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Boottop

The day after the final coat went on the topsides, I removed the remaining tape from the toerail and the tape I ended up putting at the top scribe mark.  The next step is to strike a new  line for the top of the boottop.  This will be done mostly by eye, since it is important to ensure that the line looks straight when viewed from the side.  You cannot just measure a set distance from the first line and tape; this will result in a boottop that looks like it droops at the bow and stern, a problem created by the curvature of the hull.

I first attempted to lay out the rough location of the new boottop by measuring the height of the old boottop (from bottom line to top) and transferring these measurements upwards.  however, the curvature of the hull is significantly different in the new location, and this technique did not help.  The new line was struck pretty much entirely by eye, adjusted till it looked right.  The trick is to get your eye right at the same level as the new line, and to see if it looks straight and level.  This is particularly important beneath the counter, where the strong curve of the hull requires a much wider stripe with some interesting curves to it.  I just kept moving the tape, standing back as far as possible (with my shed, this was not as far as I would have liked, but it was far enough) to see how the line looked.  I did the same thing at the bow, although here it was possible to stretch the tape from a point near the chainplates all the way to the stem, thus creating a fair line that looked appropriate.  The stripe as it ended up is about 2" high at amidships, approximately 3" at the stem, and about 6-7" beneath the counter.

With the first side taped, I was able to transfer measurements to the opposite side to make laying out that stripe easier.  There was still the "eye factor", however, to make sure the lines were fair and true.  The molded scribe lines were a little off here and there, resulting in bumps and dips in the line, which had to be corrected.

When I was sure the lines were in the right place, I checked them again, and again, and again, and again...well, you get the point!  I didn't want to end up with the boottop being wrong, so I made sure before going ahead and sanding the area with 320 grit.  After the light sanding, I cleaned with Awl Prep and tacked off.  I then applied the first coat of Snow White Awl Grip to the boottop, directly over the hull color.  I used the same quality brush as before and just brushed the paint on, carefully brushing it out and making sure if flowed properly.  The coverage was pretty good, considering it was going on over the dark blue of the hull.

After letting the paint cure for 24 hours, I sanded it lightly with 320 and repainted as before.  The second coat came out great--it covered well, leveled beautifully, and I am very happy with it.  After removing the tape, the boat really began to look finished--the bright white offsetting the dark blue is very elegant indeed.  I am also happy with the line I struck--it looks straight and even.  It's a little hard to tell where the boottop is in the photo, but if you look closely the distinction between the white Awlgrip and the old white gelcoat on the bottom is obvious.

UPDATE:  After two seasons, I decided I had to modify the location of the waterline and boottop.  Careful study while the boat was heavily loaded during our 2002 summer cruise indicated that not only was the waterline too low, effectively, for our load level, but the boottop was also sagged in the middle, the result of following the original scribe marks.  Please read more about this project here.

Bottom

After sanding off any Awlgrip that dripped and ran down over the tape onto the bottom, I rolled on a couple coats of green West Marine CPP Ablative paint.  I am doing this now only because I want to see the finished product, and do not want to spend the winter looking at the stripped white gelcoat and epoxy patches.  I will apply a third coat in the spring before launching, taking the time then to paint behind the jackstands and in a few places that I left unpainted because of pending repairs.

                              

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The hull painting is done!

 


Glissando, Pearson  Triton #381
www.triton381.com 

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