Topside and Bottom Side Paint

[JimyZ123]

I am in the process of getting my boat ready to paint. I have seen Topside paint, and Bottom Paint. My question is, what's the difference. I know bottom paint has chemicals in it to keep things from growing on the bottom. Topside paint seems to be less advanced. I am painting a trihull and the part that is inside the boat, and the top rim are what I want to paint the most, however below the rim is a medal strip and then below that is the side of the boat, half of whick will be in the water. Can I paint that part with topside paint or should it be bottom paint?

 

[Chris1956]

Re: Topside and Bottom Side Paint

Jim, Bottom paint is only used to keep marine growth (grass, barnacles) off boats that are kept in the water. It is soft and unsuitable for ny other job, not to mention toxic. It is known as anti-fouling paint.<br /><br />Topside paint is intended to be used above the waterline, but can be used on interiors and exteriors of boats. It is usually polyurethane and can be one part or two part(paint and catalyst) paint. It gives a shiny, tough good-looking finish.<br /><br />There is also polyurethane paint(usually two part) that is suitable for usage below the waterline, as well as above.<br /><br />I have been told that high-priced yachts are always painted, rather than have a gelcoat finish. This is to give them the "million-dollar" finish. They are ususally painted with Imron or Awlgrip two-part polyurethane paints. These paints are usually best applied by professional painters. I live on the coast of NJ. There are some automobile painters, who also paint boats. I was able to do the prep work, and then take the hull to one of these, who sprayed it with Awlgrip. It was a nice finish.<br /><br />In your particular case, I would paint the entier boat with a polyurethane paint suitable for below the waterline. If you are keeping the boat in the water, you will need anti-fouling paint for the "wet" part of the boat, as well. Some choices are : Interlux Perfection(two part), Interlux Interthane Plus (2 part, if still avail), Sterling 2 part Linear Polyurethane, Awlgrip (2 part).

 

[JimyZ123]

Re: Topside and Bottom Side Paint

You answered my questions and I think now I can move forward with what I was planning on doing. Thanks man this information has saved me a lot of time.<br /><br />Thanks,<br />JimmyZ

 

[DJ]

Re: Topside and Bottom Side Paint

Jimmy,<br /><br />Topside paints are fine for the bottom too, if your boat does not sit in the water for more than 72 hours at a time.

 

[MrBill]

Re: Topside and Bottom Side Paint

Jimmy...there are a number of bottom paints without anti-fouling additives, their purpose is for th ebottom of your boat. I tried top side paint at the advise of others, including a marine retailer...what a mistake. Fortunately it all peeled ooff by itself and I did not have to remove it myself. For hulls use bottom paint or a two-part epoxy that will bond not "skin" your hull so that you only do it once. Get some expert advice at a boat yard and not at the local boat accessory retailer.

 

[hdck]

Re: Topside and Bottom Side Paint

I need to repaint the bottom of my wood hull sometime soon and from what I understand from this post is that if I am going to take my boat out of the water after each use, I only need to use a "polyurethane paint suitable for below the waterline". Please let me know if this isn't correct. Thanks

 

[DJ]

Re: Topside and Bottom Side Paint

hdck,<br /><br />You are correct. Surface preperation is the key. You cannot scrimp there.

 

[geekomatic]

Re: Topside and Bottom Side Paint

I've done a gob of reading and asking around on this subject.Even went so far as to call the Interlux folks.Here's what I've gathered so far:<br />If you have a boat that's going to be exposed to fresh water as opposed to salt,the 2-part topside paint, such as Interlux Perfection, will work just fine for the bottom, provided the boat does not stay in the water any longer that 3-4 days at a time.DJ is "mucho Correcto"! The surface preperation is the key to a long lasting,good looking job, regardless of top or bottom.You must sand the existing surface with 60-80 grit to give the surface a good "tooth" for the primer to hang on to,then sand the whole thing again with 120.Apply The SAME BRAND PRIMER as the paint if possible.Sand after the primer with 120 or finer.Make sure the surface is cleaned after sanding, and I mean CLEAN.Once you paint,use very thin coats and sand with extremely fine sandpaper between them.The Interlux Perfection stuff looks absolutely wonderful, but you must follow the instructions EXACTLY! I've just helped a buddy of mine paint his little sailboat with it (top and bottom), and I plan to use it on my runabout when it's completed.The only drawback to using this particular paint is that the gloss is so nice it shows every single little wavy imperfection in the hull if repairs were done.Expensive, but worth every penny. Of course, If your boats gonna be in salt water, that's a whole different story.....

 

[JimyZ123]

Re: Topside and Bottom Side Paint

I got more information from this than I expected. That is what is so nice about this web site.<br /><br />So do I understand that you sanded, Primed, sanded, Primed, painted, sanded lightly, and painted again? I just wanted to be sure of the steps that you took.

 

[DJ]

Re: Topside and Bottom Side Paint

Jimmy,<br /><br />Go to the West Marine website.<br /><br />www.westmarine.com<br /><br />They have an extensive section on painting and preperation.<br /><br />Also, both Pettit and Interlux will happily send you brochures on their products and the prep needed for each.<br /><br /> http://www.pettitpaint.com/help/about.asp <br /><br />Here's a link to my last project. Painting instructions included.<br /><br /> http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=26;t=000270#000000

 

[geekomatic]

Re: Topside and Bottom Side Paint

Jimmy, The steps I took were:<br />Sanded,cleaned,sanded,cleaned,primed,sanded,<br />cleaned,primed,sanded,cleaned VERY WELL,Painted,sanded lighly,cleaned,painted again,had a beer.It's a very time consuming process,but well worth it.Interlux has a great instructional manual in Adobe PDF form that you can download from their site.We followed it strictly,and it works like a charm.6 weekends of hard labor.Don't take any short cuts, you'll be fine.I'll post photos of the latest project soon.

 

[JimyZ123]

Re: Topside and Bottom Side Paint

Man after reading all these posts I am so jazzed to get started. I'd like to see the photos of the project.