Hi, Does anyone know how to draw the static waterline on a Pocket Cruiser hull that has yet to see water? I have some ablative bottom paint and desire to keep the bottom paint where it should be and the "top" paint starting on the sides where IT should be. I don't know where to draw the lines? Was this in the plans, if so I missed it. :-[
Thanks, David
I asked the same question in another thread:
"I'd like to paint my Vacationer with two different hull colors: Black from the waterline to the lower rubrail, and red below the waterline, with a white stripe separating the two colors. Short of putting the boat in the water, how can I determine the location of the waterline, and what's the best way to mask the hull for painting?"
Paul, can you comment?
Dave
First off, you only need ablative (or any other anti fouling) bottom paint, if the boat is to stay in the water for extended periods of time. These paints have poison in them, to prevent marine growth, which takes several days of immersion, just to begin to form. Simply put, if your boat will be stored on a trailer and the most it will see, is a long weekend in the water, then you don't need traditional bottom paint. Any topside paint will do on a trailered boat.
As to the location of the boot stripe or waterline, well the plans should tell you where to put it, but this can often be off a little, because of the differing densities in the materials used (plus changes) in the build. For example, the race boat I just designed had it's water line painted where I told them to put it, but she was bow down a couple of inches on launch day. This is because they made a couple of changes to the design in regard to bulkhead placement and the engine was lighter then expected. They've blown up that engine and the one that I anticipated, will go back in, so she'll probably be on her "lines" the next time out.
Each build will be slightly different in regard to "trim". Some of the materials used may be lighter or heavier, even if just slightly, but enough to make her trim up or down a tad. The best advice is to launch the boat with a full load (crew, coolers full of beer, Fidel the wonder dog, etc.) and in calm water, mark the stem and transom corners with a can of spray primer. A dot of paint in these locations will easily wash off with thinner, but will show where she actually wants to float, given the materials and equipment decisions used in her build. Take her home and raise this line, established by the paint dots a couple of inches, then paint the line. A laser makes this easy, but a water level also works, though it's much more tedious to use.
It also helps to sweep the waterline up a tad at the bow and slightly at the stern too. This makes the line look "right" even if the trim changes a bit in use.
Hi,
Just want to say thanks to both of you for your sound thoughtful reply.
David
 I anticipate taking the pocket cruiser (when done)down the Chesapeake eventually for maybe a few days, maybe a week. Although I suspect I'll use it on lakes more. I'm considering using the ablative paint just in case(?) and also, I've had the paint two months now and am not sure I can still get a refund. But I will stay open to hearing others' points of measurement at stem and stern and maybe add an inch upwards at both measurement points myself just in case my boats a little heavier. I just applied two coats of inter(lux?) epoxy-type primer to the hull. It's set to paint. :-)
One year I left my boat in the water for most of the summer. When I took it out, some green slime had grown on it under the water. It was easy to wipe off, but I was lazy and didn't try to clean it off until the next spring, at which point it needed scrubbing with scotchbrite to get it off. If I had wanted to I guess I cold have used this to figure out where the waterline was!
Anti fouling paint is pretty ugly stuff. It's not very smooth, zero sheen and if left on a dry boat, becomes useless as an anti fouling paint, when you do place it in the water. Again, Anti fouling paints are for boats that are kept in the water most of the time, not trailer sailors. Anti fouling paint isn't cheap, so if you don't need the abilities of this product, spend the money on a high quality topside paint and get a better finish.
Keith, I can't count the number of times I've used a slime line to determine where to put the new boot stripe on a customer's boat. I usually mark them with a scribe or magic marker, so it's there for future reference.
Paul,
Thanks. I hear what you're saying about the ablative paint losing efficacy/value on a trailered boat(as mine probably would be). I bought the ablative two mos ago and had planned to use it sooner. Now I can't return it(ouch). I might try to sell it on Craigslist. Its Jamestown Distributors brand and sounded pretty good. But I think I'll pursue a porch paint or topside paint. I've already got two coats of interlux (epoxy-type) primer on the hull.
I completely agree with Paul: in my opinion, there's really no need for bottom paint on a trailer-sailer...Even a couple of weeks will only be a bit of scrubbing. I'd rather have a good, smooth, hard paint I could use a Scotchbrite on than bottom paint.
Mike
Mike,
Thanks. I hear the greater wisdom between you and Paul and have posted my ablative for sale on Craigslist! I'm keeping at it little by little(tortoise rather than hare). I won't be your poster child for a quick build on this pocket cruiser, but it's looking good.Â
David (6 years and counting)