Is it safe to use ON OFF on Awlgrip. I have a very dirty waterline with algae and scum and scale.
Last year I scrubbed scraped and sweated trying bleach and vinegar. Finally in desperation I tried ON OFF which shifted it like magic. Brush on wash off job done.
Now I read that it damages Awlgrip but how bad is the damage? Can it be any worse than the mechanical damage I would do by rubbing and scrubbing and scraping?
I use ON/OFF Gel on our AwlCraft paint. I find it to be a tad milder than regular ON/OFF but still effective. They key with anything is to be smart about it. Yes, acids can etch Awlgrip & Awlcraft and harm the finish. However if you do small 2' sections at a time and IMMEDIATELY rinse and neutralize that section before moving on you will be okay.
Awlgrip/Akzo specifically says to not use acids but their tech support will admit that if you use it smartly you can be okay.
*Use the acid on a warmer day 80+ is best. This helps the acid work faster and this means less time on the hull.
*NEVER work on the sunny side of the hull only work the acid in the shade.
*Once the tannin staining is gone rinse IMMEDIATELY with a hose then neutralize the acid and move onto the next small section.
*Do not let it drip into the bottom paint
*Be smart about it.....
I have seen Awlgrip ruined by dumb use of acids. It looks very dull and etched. If you work fast and rinse often and neutralize you will be okay... recommended by the manufacturer, NO. can it be done? Yes, if done carefully...