Please select your home edition
Edition
Hyde Sails 2024 - One Design

Altex specialises in the formulation, manufacture, and specification of marine coatings

by Abbie Clark 26 Dec 2021 23:46 PST 27 December 2021
Altex Hydrocoat antifoul © Altex

Altex Coatings Ltd specialises in the formulation, manufacture, and specification of high performance marine protective coatings throughout Australasia and the South Pacific. Professional and knowledgeable service, enduring customer relationships, providing world-class products backed by world-class technology for hard wearing marine environments we have the coating system for your asset.

This summer we are giving one lucky boat owner the chance to win back the value of their antifoul! To help you this summer we have some top tips!

For new anti-fouling to adhere to old anti-fouling - and work - there is one major prerequisite, COMPATIBILITY.

To be compatible for recoating, the surface must be known to meet the following criteria:

  • 1. Be Clean - free of all slime, shell, and other foreign matter (including sanding dust, if applicable).
  • 2. Be Sound - no cracking, spalling, laminating or “over-thickness” areas.
  • 3. Be Chemically Compatible - there should be no adverse reaction between new and old coatings, either at the time of application or whilst in service.

Items 1 and 2 above are within the control of the boat owner/applicator/contractor. Item 3 – please consult with the FREE AY&B Technical Services Dept or via our website if you cannot determine what has previously been used, then it is advisable to either full seal it off with PrimaShield Antifouling Sealer or fully remove.

  • Be Clean: Excellent results will be achieved by employing one of the two cleaning processes below:

  • Either: waterblast immediately after slipping with 5,000 psi to remove ALL growth, slime and hydrolysed (spent) antifouling
  • Or: waterblast immediately after slipping with 2 -3,000 psi to remove MOST growth, slime and hydrolysed (spent) antifouling AND then thoroughly wet sand all surfaces with 80 grit, and plenty of fresh water to remove the last residues of slime, salts, shell growth and hydrolysed antifouling.

The surface, once dry, will be free of any antifouling dust – wipe the surface with your hand, if your hand comes away clean, then the surface is generally well prepared.

Be Sound: A sound surface is one free of cracks, lumps, spalls etc. that requires no further preparation before recoating. Beware of excess season to season build-up of anti-fouling as this can lead to cracking and spalling, even though the surface appears sound. As a rule-of-thumb, it is advisable to strip back every three or four slippings to prevent build-up of old coatings.

Cracking often does not show up for several days after slipping, even though it can occur within hours. Cracking is induced by several factors such as excessive thickness of the total installed anti-fouling, excessive thickness of any one application, less than perfect adhesion of the anti-fouling system to the substrate and/or contamination between coats of anti-fouling.

This tendency to crack is a dynamic situation which once started will continue to its final undesirable conclusion. Such dynamic failures often show up as a total cracking and spalling of the entire anti-fouling the first slipping after a previous “perfect” slipping, cleaning and recoat. Hence the need for attention to detail and the recommendation to strip the anti-fouling system from time to time to prevent build-up.

Altex No.5 and Sea~Zone 60 Antifouling may be applied over most properly prepared antifouling’s, but with notable exceptions. All acrylic tin copolymer antifouling’s should ideally be stripped, however it is possible to prevent tin-leaching and stabilise the surface for re-coating by applying two roller coats of AY&B PrimaShield Antifouling Sealer. “Singapore” and soluble matrix types will need to be thoroughly sanded to remove spent matrix skeleton and may also require sealing with AY&B PrimaShield Antifouling Sealer.

Pettit Vivid Antifouling can be applied over most properly prepared aluminium safe antifouling’s using the surface preparation outlined above.

Sea~Zone 60 may be applied over most properly prepared cuprous oxide based antifouling’s using the surface preparation outlined above, however, we recommend that greater attention to detail be employed to ensure a very stable substrate prior to overcoating.

When in doubt, strip the existing anti-fouling back to the bare hull or sound primer barrier system and treat as for new work.

A variety of cleaners and primers are available from your Altex Yacht & Boat Paint Distributor, as well as the AY&B Antifouling brochure which lists the products available, the coating system to use.

Please note that No.5 / HydroCoat / Sea~Zone 60 Antifouling’s are not suitable for use on aluminium alloy surfaces. Please refer to Vivid Aluminium Safe Antifouling.

We recommend to refer to individual datasheets (available on our web site) for specific application, as no two antifouling are the same. Our Technical team can assist your product selection and let you know your closest reseller. Available form all leading chandleries, marinas and retailers across Australia.

Don’t forget to check out the summer promo! altexboatpaint.com

Related Articles

Gran Canaria Gloria Windsurf World Cup Day 2
Philip Köster triumphs again in Pozo Izquierdo The 37th edition of the Gran Canaria Gloria Windsurf World Cup delivered a thrilling second day this Sunday, once again marked by strong winds and the talent of the world's best windsurfers. Posted on 6 Jul
A perfect start to the 5th annual AEGEAN 600
Cloudless blue skies, crystal clear waters and perfect 12-15 knots of northerly wind At the very southern end of the Greek mainland at Cape Sounion in Attica, today's start to the 5th edition of the AEGEAN 600 was perfect: cloudless blue skies, crystal clear waters and perfect 12-15 knots of northerly wind. Posted on 6 Jul
29er Europeans at Lake Garda day 4
One race, one storm, and one big lay day vibe With qualification wrapped and the fleet now split into six groups—Gold, Silver, Bronze, Emerald, Purple, and White—Day 4 of the 29er Europeans kicked off with early optimism and an earlier-than-usual launch in pursuit of the morning breeze. Posted on 6 Jul
iQFOiL Worlds a Aarhus day 1
Full foiling conditions launch the World Championship with four high-intensity races for both fleets The iQFOiL World Championship kicked off today in Aarhus with dynamic and demanding conditions that truly tested the world's top foiling windsurfers. The wind was anything but steady, shifting in both direction and intensity throughout the day. Posted on 6 Jul
Rolex TP52 Worlds in Cascais overall
American Magic Quantum Racing win Rolex TP52 Worlds after breezy week in Cascais. Doug DeVos' American Magic Quantum Racing crew were crowned 2025 Rolex TP52 World Champions today in Cascais, Portugal. Posted on 6 Jul
Red Bull Sailing Academy Opens
A new hub for current and future superstars to reach the top of their sport Marina Monfalcone, North Italy, made waves yesterday, as sports superstars gathered to open the Red Bull Sailing Academy, marking the beginning of a new era in the sport. Posted on 6 Jul
Gran Canaria Gloria Windsurf World Cup Day 1
Philip Köster edges out Marcilio Browne in one of the closest finals ever Philip Köster edges out Marcilio Browne in one of the closest finals ever as Pozo delivers 50 knot winds and waves. Posted on 6 Jul
America's Cup: French give the Brits the "Hurry-up
Frustration builds between Cup factions over lack of progress with Protocol. Last weekend's missive from the French America's Cup challenge team is further evidence over the building frustration with progress towards the 2027 America's Cup in Naples. Posted on 6 Jul
The oldest video footage of Moth sailing
A look back into our video archive, to when the name of this class first settled down We delve into our video archive to find the oldest possible videos that show Moth racing. Are these International Moths, British Moths... or was the name still Olive, Inverloch 11ft, National Moth or Brent One-Design?! Posted on 6 Jul
GKSS Match Cup & Nordea Women's Trophy overall
It is the first time the Match Cup Sweden title has been won by a Danish Skipper Denmark's Jeppe Borch/ Team Borch Match Race, and France's Pauline Courtois/ Match in Pink by Normandy crowned the new champions of Marstrand in a day of fierce weather for the final of 2025 GKSS Match Cup Sweden and Nordea Women's Trophy in Marstrand. Posted on 6 Jul
Switch One DesignPalm Beach Motor YachtsAllen Dynamic 40 Footer