Painting the bottom of your own boat is doable, but there is a lot to learn in doing it effectively. For starters; you need to know that different types of paint will affect the chemical compound of the boat’s materials depending upon the chemicals that are in the paint. Bottom paint is quite toxic, so knowing just what paint works best with the type of boat you’ve got is important. There are two types of bottom paints; Hard and Ablative. Hard boat bottom paints are meant to be applied solely to metal bottoms and must be set in the water within three days of application, or they lose their effectiveness. Hard or (metal) bottom paints will adhere themselves to a metal bottom permanently without rubbing off.
Copper paints, or Ablative paints are made of softer chemicals that will react each time the boat is set in water. Ablative paints are meant for softer surfaces such as fiberglass, or normal boat bottoms. Ablative paints will rub off when touched, even when dry. The metal or hard paints should only be used on drives, while Ablatives may be used on hulls. You can always apply an Ablative paint over a Hard paint, but never a Hard over an Ablative paint. During preparation to painting, be sure you place the tape along the top edge of the waterline evenly. Use a 60 grit sand paper scuff to ready the surface of your boat bottom for painting, then apply a barrier coat. This will protect the surface of what ever material the boat is made from of the chemicals in the paint, like primer on a car.
Be sure to wear gloves and safety eyewear when painting. As mentioned above, boat bottom paint has very harsh chemicals in it and you wouldn’t want to put yourself at risk for a bad chemical reaction. Application of the paint can be done with any type of applicator, be it a brush or paint roller. For best results however; it is better to have the boat elevated at a good level for easier application. As a helpful tip: If you’d like to keep the finish of your new paint job free of scum and other water build-up, then add some Cayenne pepper to the paint.
A good finish on the bottom of your boat is important and as you can read, there is a lot to do from prepping the surface of the boat bottom, to the actual application of the paint. In theory, this really isn’t that much of a challenge, just a lot of work, so if you’re up to it then go for it. However, if you aren’t sure of where to begin really, then calling on a bottom boat painting professional isn’t a bad idea either. After all, they have the experience and might be better equipped to handle the job. Since boat bottom paints are expensive, it might also be wise to ask a pro about some less costly alternatives in either the color or the type of paint you are using.