ross 930 exterior repaint

[saltmonster 0]

Hi

I am looking at getting the outside of my ross 930 repainted. Due to hardstand prices I am looking at refitting in my backyard and getting all the prep work done my self and then getting a professional to paint. I have talked to the vinyl guy and says the paint has some kind of issue, where all the paint has to be removed? I feel the paint has done a brilliant job for 20 years plus but a tidy up is needed. 

I have refitted the inside, and learning from my mistakes. These jobs are harder than said to be done.

My real question is what kind of time and effort is required eg. 

- What paper grit do you go up to on the hull?

- What paper grit do you go up to on the deck?

- How many coats of primer and paint is required?

- How many much sanding is required between coats of paint?

- Whats the best filler to use ?

- What tools are needed to speed up the process?

- What technquies are best to speed up the process?

- or am i better to get a professional to do the prep work who are probably quicker and more efficient than me? (does anyone recommend any prep crews?)

Please any recommendations or hacks you have learnt over the years

[Y88 5241 25]

Looks like it might have had the latex primer which fails over time due to UV.

as someone who previously managed a boat painting company, a lot of your questions depend on your chosen paint system as can vary quite a bit. Do you have a system in mind?

[saltmonster 0]

nah, I don’t have a paint system in mind at the moment 

[K4309 259]

We did what you are describing on our own boat. Prep'ed it and got a pro in to do the top coat. Brush finished, which is good for 2-5m, as opposed to a spray finish which is good at 0.5-1m, but costs much more (if done within OSH rules).

Get a big random orbital sander. Start with 40 grit to strip everything back. Don't skimp on the sander. I've seen guys trying to use 'lady' sanders, it was hopeless. Loaned them ours and they were all smiles.

I can't remember the details on layers etc, as it was about 12 years ago, but follow the directions on the tin. Seriously, I'm not trying to be a smart arse. Read the tech spec's for what you are using, understand them, and follow it. We used the International system, so while I might have the names slightly wrong the products are still available and the same. All two pot. Some sort of undercoat, possibly Interprotect (we def used that below the water line) or possibly YRA 'number-number'.

We used a guide coat for sanding between layers, esp undercoat to to coat. It's like a blue stain. You sand it off till there is no blue, shows the dips and dings up super well.

We would have used the International top coat 2 pot. Possibly called toplack?

Sean Rowe was the boat painter we used. He is mobile and very good. That was 12 years ago now so no idea if what he is doing now. There was two of them, one brushing on, one tipping off. Looked mint.

PS I'm not saying the International products are best, it's just what we used and understand. And they have established track record. It sounds like there are some very good automotive paints at a fraction of the price that are just as good. There is of course the whole question of single pot or two pot, and I get mixed up but fancy new technologies around now too.

PPS a proper scaffolding set up is worth it's weight in gold too. Not just for osh ladeda (if you break your arse falling off a ladder, you will never finish your project), but it's loads faster being at the right height to do the job, elbows below shoulders is soo much easier, and you just walk along getting the job done.

[saltmonster 0]

Awesome thanks for the response. I’m now wondering when to rip out the long board and for  generally how long? (I understand every paint product  and boats requires different  amount of time and effort) 

[Frank 157]

All of what K4309 said and I would not apply 2K polyurethane  directly over epoxy undercoats on external surfaces, use the system undercoat as a barrier between the two.

International Perfection is a good system but also talk to these guys

https://www.protectivepaints.co.nz/contact-us

 

[K4309 259]

10 hours ago, saltmonster said:

Awesome thanks for the response. I’m now wondering when to rip out the long board and for  generally how long? (I understand every paint product  and boats requires different  amount of time and effort) 

Never used a long board.

I think they are for new builds when you need to get massive humps and hollows fair. If your boat is basically fair, and you sand it back, then you shouldn't need any longboarding.

Noting that when you use that blue guide coat you'll get a handle on it. I'd expect touch ups rather than bulk fairing.

[Psyche 633]

Definitely get a longboard and learn how to use it if you want a fair hull

 

[Psyche 633]

7 hours ago, Frank said:

All of what K4309 said and I would not apply 2K polyurethane  directly over epoxy undercoats on external surfaces, use the system undercoat as a barrier between the two.

International Perfection is a good system but also talk to these guys

https://www.protectivepaints.co.nz/contact-us

 

You can use 2k topcoat over epoxy undercoats no problems but you have to understand the materials and do things in the right order.  I usually do all the divots, dents and repairs first to the best standard I can then put on plenty of epoxy primer. If there are lots of uneven areas before sanding I put on a guide coat which can be either a bit thinners with a splash of dark paint put on with a rag or use the proper 3M charcoal tool. If it's a big area you can spray a contrasting colour as well but whichever method you decide to use, guide coating is the way to go for a fast fair job. This fill, fair, paint and sand process can take a few cycles to get it all done. For tiny imperfections or pinholes use 3M vinylester glazing putty to speed things up.

Epoxy primer goes hard and keeps getting harder until fully cured which may take weeks, the overcoating window is very short without sanding to get a mechanical grip, hot coating is for antifoul but you really want to get sanding as soon as its not clogging the paper to make the job easy. Leave it a few days and its like sanding concrete plus if you leave it for more than the recoat window (2 weeks??) then you must reapply it. All this info is on the data sheets. 

Experienced painters can mix and match but for amateurs select a system from one manufacturer and stick with it following their instructions carefully paying special attention to timeframes, humidity, temperature and using the right reducers. Paint is expensive but if you consider your time and how long it lasts, its pretty cheap to get the best. International is good, easy to apply and you get what you pay for.

 

[Frank 157]

Full disclosure I'm no paint expert, my comment about using 2K topcoat on an epoxy base coat are purely based on personal experience and observation of problems other club members had with this approach.

Essentially what I experienced was that the topcoat degraded over time by dulling  and becoming  somewhat chalky in the sun (after 3 seasons).  It was more a cosmetic failure than anything but still disheartening after the work and cost involved in a re-paint. It became a bit of a running narrative in the club as several boats suffered the same problem and needed repainting. Our tame professional painter at the time muttered that he had seen it before and did not understand why counter staff at various suppliers still promoted the system. I stress it was OK inside the boat but just not on external surfaces. My totally non-scientific take on it was that the epoxy was interacting somehow triggered by UV and/or heat. Others might have gotten away with it so you pays your money you take your chances I suppose but I would stick to what the manufacturer recommends  and at least you might have some comeback if there is an issue. if you need the epoxy base coat for other reasons then I would cover it with the 2K polyurethane primer first.

[raz88 96]

Consider phoning chains ropes and anchors, asking for grant, and saying you have a 930 you're putting in your backyard for refitting and painting.

He did the same with his 930 a few years ago and is normally quite generous with his advice and happy to talk 930s.

[saltmonster 0]

On 8/01/2024 at 9:17 PM, raz88 said:

Consider phoning chains ropes and anchors, asking for grant, and saying you have a 930 you're putting in your backyard for refitting and painting.

He did the same with his 930 a few years ago and is normally quite generous with his advice and happy to talk 930s.

Cheers for that, I’ll hit him up