Boat Parts Info

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Fall is the perfect time to consider refreshing the old Bottom Paint  The weather in most places is just about perfect for an outdoor application of paint, the yards are coming off their rush-rush, do-it-now season and now have more patience to do it correctly. There is generally less demand to have the boat out on the water. Also, you will probably get a discount at the haul-out yard because you are doing the work off-peak season.

Fall is the perfect time to consider refreshing the old Bottom Paint 

If now is the time, here are a few important things you can do to make your work pay-off is to follow these simple steps:

  • Purchase the desired bottom paint in advance of your haul-out and then take the time to read the can and its application instructions. Go2marine offers many top brands and types of bottom paint to meet the needs of many. Make sure to match the paint to the boat and the intended use of the boat. Special consideration should be given if paint type is being changed from the previous brand and type.
    • Contact the manufacturer if you have any questions. The process of painting the bottom of a boat is time consuming and expensive so make the most of it by being as prepared as possible. Manufacturers are standing by ready to help.
    • Arrange for the haul out and tell them that you are planning on doing a bottom paint job. Ask if they have any special considerations for the bottom or the boat (take down the furler, tenting, electrical needs, extra blue tarp, allowed sanders, haz-mat considerations, etc). Try to plan on dry, weather, if possible
    • Be there in advance of your scheduled time and haul out the boat. The yard will instruct you all the way into the sling at which time you can assist by providing knowledge of where best to position the slings. Stay with (not aboard) your boat all the way until it is secured in the stands. If something happens or if they have questions, you will be there.
    • Clean the bottom paint that is there when the boat comes out of the water. Many yards include a “free” power wash as the boat is lifted out but before it is put on the jack stands. Either tell the yard you would like the deluxe, pre-paint job power wash and are willing to pay for it or slip the person doing the job a $20 or two to give it extra attention. This will save hours later and it is generally more environmentally friendly than sanding as for the most part yards capture and pre-process the run off waste water.
    • You will know it is an ideal time to reapply bottom paint if, following the pressure washing the remaining bottom paint appears to be consistently thin, possibly even mottled with the undercoat barely peeking through.
    • Inspect the hull for loose or degraded bottom paint that remains and remove it properly. If there is a lot or it is coming off in big flakes, consider stripping the entire bottom. This may also be required if the type of bottom paint is changing and there is concern (see above about checking with the paint manufacturer) that adhesion may be a concern.
    • Do a once over for damage to the hull that may have occurred since the last haul out. Now is a good time to pay attention to everything that lurks below the water line, including inspecting and possibly rebedding thru hulls transducers and instruments.
    • Tape a rain and or dew gutter above the bottom line so that in the event of precipitation, it doesn’t roll down onto the intended work area.
    • If all of the previous bottom paint is missing, consider applying a new barrier coat before the bottom paint is applied. If so, consideration should be given to using a barrier coat to two part epoxy that is of contrasting color to the new bottom paint so that future wear-though is apparent.
    • Sand and scuff the now clean bottom paint, taking special precaution for yourself and the environment. Most bottom paint still on boats is toxic by design.
    • Wash it so that the new paint is adhering to a clean bottom, not a dusty one where adhesion will certainly fail.
    • Consider a base coat that is different to the final coat color so that you have an excellent progress indicator for future wear.
    • Take time to mix the paint thoroughly. If the new paint contains copper, it takes time to mix it into the paint evenly.
    • Using painters tape, tape the waterline well so that when you strip the tape the new line is crisp and even. Also consider protecting underwater thru-hulls and transducers with tape so that they are not accidentally coated with fresh paint.
    • Apply several thin coats rolling consistently from top to bottom, keeping a single wet edge. This work is benefited by a second painter tipping and touching up as the line of wet paint moves down the hull. We have seen warranty claims against paint manufacturers go nowhere good because the paint was applied too thickly with too few coats.
    • When going for those little 12 inch squares under the jack stands, don’t move them without involving the yard. This should be a no-brainer but many a boat has tipped during painting because shortcuts were taken here.
    • If using copper based-based paint, take care to avoid coating any underwater aluminum parts as it is incompatible and may cause permanent damage.
    • Let the new paint dry a couple of days, especially if the weather is cool and damp.
    • Don’t forget the prop. A prematurely fouled prop is a bad thing. We recommend a good coating or two of Pettit Barnacle Barrier. If properly applied, it will last about a year. Another product group that is new to the US market is Prop Speed. Propspeed system is best used on propellers, shafts, struts, rudders, trim tabs, keel coolers, bow and stern thrusters, pod drives, sail drives and other underwater metal. Propspeed is specially formulated to prevent marine growth from bonding to metal surfaces below the waterline.
    • Peel the tape and Install new anodes. We have those too and while you are at it, buy a couple of spares because they have a way of disappearing over time.
    • Record the date, and conditions and type of paint used. Consider referencing the paint batch numbers as well.
    • Take plenty of photos below the water line, especially of the locations of specific hardware. A side profile is great to have that you can provide to the yard the next time the boat is hauled. Print the photos out and place them aboard in the maintenance log for future reference.
    • Splash it and enjoy.

Though dealing with yards is a topic unto itself, it is always advisable that any time the boat moves from the water to jack stands and back that the owner be there to witness it from start to finish. If something goes wrong and it occasionally does, it is best that it be witnessed and discussed immediately between the yard manager and the boat owner.