Supplies for 40' cat bottom paint?

[karenmccraw]

We're going to do our own bottom paint while our boat is on the hard for engine replacement.



We'll get a dustless sander to comply with the yard's requirement.



I've already bought 5 gallons of Petit paint.



The yard is a long way from any reasonable store, so want to go as prepared as possible.



Having never done this before, just wondering if any of you could list the supplies we'll need, in general?

[mikedefieslife]

Most will say you should be wet sanding, so that means using air tools (unless you want to do it by hand), as wet sanding with an electrical item could be dangerous. That being said in Greece I saw the yards just using regular bosh electric sanders.

A good shopvac will help limit dust, and Abranet style discs. When sanding my boat, I managed to break 3 sanding pads, as it isn't alway easy to limit the pressure due to the shape or the hull and angles the sander was held at.

Obviously you need to make sure that the paint you will be applying is compatible with what you have on already, or you'll need some sort of primer. But that goes without saying really.

If it's hard antifouling, or coppercoat, it might be better to have it blasted. After a week removing a coppercoat style product, I realised that I should have just paid to have it done and used my time more wisely.

p.s don't forget your protective overalls (go larger than need), gloves, a good dust mask and eye protection. Do not sand without them life is too short.

[karenmccraw]

Thanks. Yes, we're going back with the same Petit Ultima paint that was previously painted, so no worries there.

[karenmccraw]

Also, how many paint rollers did you end up needing? Just one or two, or do I need multiples?



Once you're ready to paint, with 2 people, can you finish in one day? (I assume we're getting 2 coats out of the 5 gallons)



And what masking tape do you like?

[Debgen]

I have a 41 cat and 3 gallons covers 2 coats nicely I stopped using the 9 inch rollers and went with 6 inch foam rollers from Home Depot/Lowes. usually bought a 10 pack of covers. The foam rollers put on a smooth finish and doesn't weight your arm down and my wife and I put on 2 coats in 3 hours.

[stormalong]

Since you are using the same paint all you have to do with the sander is to clean the surface and fair any rough spots. Don't take off any more of the old paint than necessary.


One roller should do it if you paint without stopping. Buy two and save one for next time.


I always tell people to buy extra supplies and return unopened packages. Far easier than running out for supplies in the middle of a job.

[Defeverboat]

Just finished bottom paint on Bluemoon.sticky back sandpaper is the best .went through two bases of hook and loop and the sanders are done. Portacable sander the best with sticky back! Lots of Foam rollers for primer three coats interlux 2000 and paint the props and all metal. For bottompaint fuzzy rollers. We had delamination on the bottom after Harvey. We were at Rockport Texas .

NEVER AGAIN GOOD LUCK

[donradcliffe]

Go with #80 grit sanding discs for the general bottom--buy a 10 pack if you are using a 5" sander, 6 pack if you are using 6" Fesstool. If you have to feather out flaking paint, a few #60 discs will make that job go faster.

Roll of 1 to 2 inch blue masking tape for the waterline

1.2-2" chip (throw away) brushes--get 4, use 2

Mechanical paint stirrer and cordless drill motor to drive it.

Needless to say, bring PPE--dust masks, googles, and disposable gloves at a minimum, , tyvek suits if you're snowflakes. Old clothes and shoes.

Avoid cheap rollers that dissolve in the paint solvent and leave you with clumps of roller nap/foam all over the bottom.

Have fun, and don't forget to hydrate if its hot.

[Cheechako]

-Green tape. DO NOT try anything else! I know it's expensive, but try removing paint that hardened up and you wont think so. In hot places the blues goes hard real fast. You dont need it too wide, depending on your roller skill!
-You bought too much paint, but I guess it will save.
-Unless you have any issues you only need to scuff up the existing paint . If you do sand it all off by all means epoxy coat the bottom.
-After all sanding is complete spray wash the bottom with water and let it dry over night. That removes all the dust well.
-Have you considered drilling a hole in each rudder to see if they are water logged? If you do, get some epoxy filler for the hole. At 6 years old one of the two rudders on my Lagoon was waterlogged.

[karenmccraw]

Thanks to all for the advice. I've got a large "cart" at Amazon now!

[Excalibur5]

After just doing this on my 37' cat I'd also recommend some sound deadening ear muffs. Possibly put ear buds in your ears first to listen to something else to save the monotony. I also wished I had a seat on rollers to save sitting for hours while sanding. We did have some adhesion issues so the sanding took 3 days for two of us while concurrently doing some minor repairs.

[JasonS]

Hi Karen,

We always have the yard paint our Manta, but 4 gallons will yield 2 full coats plus enough for a 3rd coat at the waterline on our Manta 40's and you'll likely have enough left over for some touchups at the stern steps which tend to wear quicker - as you know, with low fuel and water they come out of the water pretty nicely.

Also, you might want to consider having the yard acid wash and do the sanding and you guys just paint. Bottom paint is nasty stuff - if you're going to do the sanding make sure you have tyvek suits, hoods, masks and really good respirators. Not worth the potential time and health risks IMHO. Painting is the "fun" part!

Don't forget that your bottom paint is not safe to paint on the saildrives. Get paint specifically recommended for aluminum saildrives. After spending $$$ on prop paint, I've found it's just not worth it. I scrape the folding props when necessary diving the bottom and apply a coat of lanacote underwater. It helps... Good luck! Jason

[Milko Berben]

Take the masking tape of directly after the paint job is done other wise you might crack/lift the paint the paint on the border line.