Cover

Joe · Oct 18, 2019

Interlux micron is an ablative or sloughing paint. Petit Trinidad is a modified epoxy or hard shell paint. I'll leave it to you to research the difference between the two. I can save you some time by telling you that hard shell paints are most effective for boats that stay in the water year round. Ablative paints are preferred for those that don't, such as trailered and seasonally stored boats. So.... don't use the Trinidad... it's way too expensive anyway.

It is pretty easy to repaint your trailered boat every season with an ablative paint so it really doesn't make a lot of sense to buy the expensive paint. Sanding every year to remove paint is unnecessary most sailors will change paint colors after the first coat so they'll know when it's time to paint again. Us a 9" roller to apply and discard after use... don't try to clean the roller. Use a handle extension to save your back, put extra coats on the leading edges of the keel and rudder.
But most importantly: I highly recommend following the manufacturer's instructions as close as possible for best result. These are always found on the paint can label and the manufacturer's website. Most vendors post them also. Here's info for Micron

Richard Gresham · Oct 21, 2019

I agree with Joe, except I prefer the Petit Hard Bottom epoxy. For the money it goes the furthest. Just touch up your leading edges and just below the waterline before you splash and it should go many years before you have to repaint the entire bottom.

captcoho · Oct 21, 2019

mll said:
I'm first time owner 1986 Catalina 22, and I'm in the process of refurbishing.
1. There numerous hole openings in the cabin flooring, I have measured them including the curving, does catalina sell the covers for them, and what are they called?
2. I am planning to sling lift the boat off the trailer and redo the bottom, any suggestions on sanding and repainting with Interlux Micron or Trinindad, any suggestion on size of sanding grit?

Being that you are in fresh water and on a trailer, you want to consider either VC-17, by Interlux, or Petit's version that offers SR21 percent copper versus the Interlux 17%, and West Marine has their own FW21.
These paints are much easier to maintain season after season, and do not require yearly sanding. As well as being the racers choice.
My first trailer boat did not have bottom paint due to being on a trailer when not in use. My next trailer boat had VC-17.
If your boat has no bottom paint and may be in the water for the entire season, you will need to consider an Epoxy Barrier Coat to prevent Osmotic blistering. There are threads in SBO that suggest your 1986 hull's Gel-coat will not have any osmotic protection.
Either way, West Marine offers quite a bit of information under the Advice and How To tab of their websiteI
Be sure to check the State you use your boat because areas are now banning the use of cuprous oxide biocides

captcoho · Oct 21, 2019

Are Brand Name Builders using Epoxy now?

I know this might be a silly question, but I couldn't find a straight answer anywhere else. Have the major brand name boat builders shifted from Polyester Resin to Epoxy Resin for assembly line GRP construction? Vinyl Ester Resin maybe? (Not talking about custom boats, just the big name...

forums.sailboatowners.com

Meriachee · Oct 21, 2019

It also depends where the boat is. Up north, way up north, there is a discussion about the need for anything beyond a good barrier coat. The boats are not in the water long enough, and stuff is easily washed off the hull.