Bottom Repairs

[Tqxin]

I have a 1975 Rhodes 22, that will stay in the water (salt water) all of the time when finished.
Bottom paint is chipping off down to the fiberglass; I can see a few spots that have been patched in the past. No leaks that I am aware of (it holds water quite well after some rain ) what would be the best methods to refurbish the bottom of this boat. Of course some sanding will need to be done, but should I sand it all down to the glass or just get the loose stuff off (most of it is chipping off). After sanded should I cover the bottom with epoxy followed by gelcoat and then anti fouling paint? Should I do it in that order? Give me a rundown of what you would do and how you would do it please.

[T37Chef]

The spring after we purchased our boat, there was a lot of paint build up and was flaking off, etc. So I had the bottom blasted only to find these... Mostly little blisters, not deep, with the exception of about 10 that I ground out.




Here I am sanding ALL the remaining bottom paint off...wear proper safety protection!!!





Still going...all day long...





After sanding down to white gelcoat, I washed it about once a week for about 4 weeks to remove bad stuff, acids, reisdues, etc. then let it dry for another 6 weeks or so

Then I started to fill and fair the bottom. I used West System with filler which has the brown color you see below. I also tried a vinylester product (forgetting the name at the moment) which you see in blue.

Remember...epoxy over the vinylester okay, but not the other way around







more filling & fairing...





Finally...the barrier coat application (gray)...starting to see progress, I put 5 coats on the hull with 3 more or 8 total on the bottom and forward part of the keel & rudder...









Before the last coat of barrier coat cured, about 3 hours in 90 degree Maryland weather, I applied the first coat of bottom paint. Doing this should help form a good bond between the two. I used an ablative paint in black, of which I applied two coats.







Here I start to apply the third bottom paint coat, but in blue, so I can see when its time to re-coat...








Finally done painting...yea right...






Here you can see where I removed the PO's try at a boot strip, I just took the bottom paint up another 1 1/2"...





Finally this spring I painted a new boot stripe... I need to do some repairs to the stripe due to the sling when we splashed her but I'm pretty happy overall.

Its been three years now since I have barrier coated the bottom, leaving the boat in year round. This spring there were no signs of blistering.





Total cost to blast, sand (ended up renting a sander from the yard), fillers, barrier coat and three coats of paint, if I remember correctly was just over $2000.00 and about 60 hours of time give or take.

Good luck, theres lot here that you can search for on the topic...

[camaraderie]

Nicely documented Chef!

[Tqxin]

Thank you Chef.

[L02314564]

Very informative Chef! Written so that even I can understand. Thank You!

[sailingdog]

Nicely done.

[T37Chef]

[sailingdog]

Maybe, a bit biased there.

Originally Posted by T37Chef

[cutterorient]

T37 Chef, nice. I am doing the same thing right now on a 1983 Mason. After soda blasting - which uncovers all defects/impacts/etc - I too noticed what I call irregularities in the gelcoat. Bumps in places that held no water (visually or with the moisture meter ) and their counterpart the crater. The craters are only the gelcoat. I sanded the entire bottom, am now filling with MAS FLAG epoxy / micro baloon mix. The number of the little 'imperfections' are likely more than 10,000. I am also doing a rudder repair and repairing and fairing the substantial area on the underside of the keel. When she is sanded again to fair ( all excess faring mix off ) I will barrier coat with the same epoxy, unthickened of course. I will tint the epoxy grey and let it to a full cure, slap some paint on and then, of course, sail it. I chose to barrier coat with MAS for the following; have used in the past with great results for other projects, VOC free, blush free, excellent customer service when I called with loads of questions, cost effective, you can vary pot life/ mix and match resin hardeners, and there is no 'window' to paint with antifouling. Just let it cure fully and then paint when you want.