How many coats of antifouling need to be applied? 

In standard conditions, two or three coats are sufficient. It is very important to apply the product undiluted. If absolutely necessary, up to a maximum of 5% of the diluent indicated in the technical data sheet may be added.
For optimum results, it is essential to apply the thickness of antifouling indicated in the data sheet.

Does a primer need to be applied before antifouling on a new fiberglass boat? 

Yes it does, usually antifouling does not have good adhesion on fiberglass. It is necessary to:

  1. remove the wax or release agents applied on mouldings using special dewaxing products
  2. sand the gelcoat with fine sandpaper
  3. apply Defender (two-component primer) or AnchorPrimer (single-component primer).

If old paints have been removed from the hull, a primer must be applied on gelcoat as recommended for new fiberglass hulls.

What type of antifouling should I use? 

It depends on the type of boat and its use. An hard matrix antifouling (e.g. Altura 619, Scirocco 622, etc.) is usually recommended for fast boats (speed greater than 25 knots) and boats which remain moored for long periods.
For slower boats (speed less than 25 knots), a self polishing product is recommended (e.g. Mistral 633, Corsaire 611).
For regatta boats, a hard type antifouling is recommended with the addition of Regaflon to improve performance. 

How can I verify the compatibility between old and new antifoulings? 

The type of the existing antifouling must first be determined. Hard matrix coatings can be overcoated both with the same type and with self-polishing products, whereas self-polishing coatings can be overcoated only with the same type of product. Prepare the hull by light wet sanding, wash with high pressure water and once dried apply the first coat of antifouling.
If the existing type of antifouling is unknown or it is desired to change from a self-polishing product to a hard matrix coating, a coat of Mistral Fondo undercoat must be applied. 

What is the osmosis prevention cycle? 

It is a barrier which protects fiberglass hulls from humidity.
The Boero YachtCoatings osmosis prevention cycle consists in the application of 300 microns (about 2/3 coats) of Defender epoxy primer on the hull over gelcoat previously treated.

What is pot life? 

This is the time within which the base and hardener mixture must be applied. After this period, the viscosity and other key characteristics of the mixture change.

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