I'm a bit stumped about my bottom

[Hardalee53]

I'm stumped about an upcoming bottom job and any thoughts/advice welcomed!

Last summer I bought a 2005 Tartan 3700 and sailed from Connecticut to my home in Freeport, Texas. She has proven to be a solid boat and I've completed several needed refits: bilge pump, windlass motor, winches, AGM batteries, cabin and nav lights, AIS, high-output alternator, fuel lines, running rigging, stanchions and lifelines, etc.)

But what about bottom paint? There's quite a build up of Awlgrip bottom paint (you can see the layers at the waterline) and the previous owner (who bought the boat new) told me that the boat has an epoxy hull and that there is no need to sand or blast down too far because of it. Apparently the epoxy has a wax that is not conducive to another primer base.

When he spoke of "an epoxy hull" (his term, not mine) I take it to mean that when Tartan built the hull they used a thermosetting resin epoxy as opposed to polyester resin.

Does this sound right? Anyone on the forum know how Tartan laid-up their hulls?

With the boat being 15 years old and with several layers of Awlgrip, do I just need to remove the topmost layers of Awlgrip and repaint and not worry about barrier coat removal and reapplication?

Thanks!

[psk125]

The Awlgrip Company makes an antifouling paint called Awlstar. Is this what you have on the bottom? People generally use the term Awlgrip to refer to on the shiny paint used for topsides, so your post is likely confusing many people. The Previous Owner seems to have read this from the builder: http://www.tartanyachts.com/wp-conte...ecs-090313.pdf Based on that, he’s right. DON’T sand off more than paint from the bottom. It and the keel seem to have good epoxy barrier coats in place - don’t breech them. You will need to look into what type of antifouling paint works best in Freeport TX. It may be the Awlstar brand, or it may be something else. Ask around. It may or may not be compatible with what you have on there now. That will determine how much of the old stuff has to come off - just a touch,( to give it some “tooth” for the new paint), or all of it, (so that the new paint doesn’t just slough off because it’s not compatible). The guys at your marina should be able to explain this in better detail.

[GordMay]

Tartan 3700 Specs:
Hull
• NPG Isophthalic gelcoat
• Infused epoxy modified vinylester hull
➥ http://www.tartanyachts.com/wp-conte...016.pdf?x16223

[Hardalee53]

I don't know what I have on the bottom but will find out. Thanks you for the clarification on Awlgrip vs Awlstar. That said, with an upcoming haul out I feel comfortable in just doing a light sand and applying the appropriate antifouling. I will inquire about Awlstar and other bottom paints to determine compatibility and to know exactly how much to take off. Thank you both!