Touching Up Chipped Ablative Paint (Micron CSC)

[pdo333]

I have about 20 spots where last season's Micron CSC has chipped off a little and I'd like to touch these up and go another season. ~98% of the paint is in good condition. What kind of precautions do I need to take? Respirator? Full suit? Hazmat? The boatyard does not allow wet sanding.

The process I'm imagining is something like this:

1. Chip away all the loose pieces of paint with a putty knife
2. Sand chipped edges lightly with ~100 grit
3. Roll some new paint over the affected area

Any recommendations? Thanks!

[T37Chef]

You definitely want to wear some protective gear including a good respirator, eye protection, and suit before you start scraping and sanding.

You can pick most of it up at Home Depot or Lowe's, except maybe the full face mask. Heres one by 3M Amazon.com: 3M 50051138541465 6800 Med Full Face 3m Respirator: Home Improvement You could get away with a pair of protective eye wear and just a respirator such as 5000 Series Half Facepiece Respirators - Medium

Coveralls Amazon.com: DuPont TY127S Disposable Elastic Wrist, Ankle & Hood White Tyvek Coverall Suit 1428, Size Large, Sold by the Each: Home Improvement

Chipping away the paint with a putty knife or paint scraper is fine, but you will probably wanna sand after with a 60 or 80 grit using an orbital type sander with a vacuum attachment. PLEASE DO NOT sand without a vacuum attachment, your dust will settle on your boats deck as well as any others nearby and after the morning dew, will be a PITA to remove, its rude and unfriendly to your neighbors and the environment IMO. After sanding I like to power wash everything and let it dry before painting.

If your changing paints, you would want to check its compatibility with the CSC before application. I used CSC once, never again...I just doesn't ablate on my boat therefore I have been sanding it away this spring. I am hoping Pettits SR40 will do better.

If you have a lot of paint build up, you may consider sanding everything or worst case having it soda blasted to remove all and reapply, and consider a barrier coat before that

[RichH]

Originally Posted by pdo333

I have about 20 spots where last season's Micron CSC has chipped off a little and I'd like to touch these up and go another season. ~98% of the paint is in good condition. What kind of precautions do I need to take? Respirator? Full suit? Hazmat? The boatyard does not allow wet sanding.

The process I'm imagining is something like this:

1. Chip away all the loose pieces of paint with a putty knife
2. Sand chipped edges lightly with ~100 grit
3. Roll some new paint over the affected area

Any recommendations? Thanks!

4. Use a large polyethylene plastic trowel and 'wipe' over the where you rolled on the new Micron. This will wipe the fresh paint from the old surface and help to fill in the 'spots'. Let dry a bit before you roll on the 2nd, 3rd. etc.

You can add some micro-baloons to the first few 'fill coats', with stright paint for the final 'fill'.

Once you see how such a surface quickly 'levels', you'll want to do the whole hull this way .... for a super smooth surface that is exceptionally fast in light wind conditions.

In my experience when Micron CSC begins to flake off, its time to aggressively power wash the bottom to remove 'most' of the Micron ... and then start all over from 'new'. It means that youre applying the Micron TOO THICK and its then losing its adhesion before it abrades away.

All you need to sand Micron is an efficient dust mask, as there are no "volatiles" present in 'cured' paint.

[pdqaltair]

Originally Posted by T37Chef

You definitely want to wear some protective gear including a good respirator, eye protection, and suit before you start scraping and sanding.

You can pick most of it up at Home Depot or Lowe's, except maybe the full face mask. Heres one by 3M Amazon.com: 3M 50051138541465 6800 Med Full Face 3m Respirator: Home Improvement You could get away with a pair of protective eye wear and just a respirator such as 5000 Series Half Facepiece Respirators - Medium

Coveralls Amazon.com: DuPont TY127S Disposable Elastic Wrist, Ankle & Hood White Tyvek Coverall Suit 1428, Size Large, Sold by the Each: Home Improvement

Chipping away the paint with a putty knife or paint scraper is fine, but you will probably wanna sand after with a 60 or 80 grit using an orbital type sander with a vacuum attachment. PLEASE DO NOT sand without a vacuum attachment, your dust will settle on your boats deck as well as any others nearby and after the morning dew, will be a PITA to remove, its rude and unfriendly to your neighbors and the environment IMO. After sanding I like to power wash everything and let it dry before painting.

If your changing paints, you would want to check its compatibility with the CSC before application. I used CSC once, never again...I just doesn't ablate on my boat therefore I have been sanding it away this spring. I am hoping Pettits SR40 will do better.

If you have a lot of paint build up, you may consider sanding everything or worst case having it soda blasted to remove all and reapply, and consider a barrier coat before that

For a small amount of sanding on soft paint like that, an orbital sander with vacuum attachment, using drywall sanding mesh works very well; the dust goes right through and the mesh resists fouling.

PPE is always a good idea, but if everything is connected right, there should be very, very little dust. If some dust is coming out of the shop vac, consider putting a hose on a discharge, venting into an old pillow case.

However, just a little scraping should get 90% of it. I did this many times.