Jump to content

Rusty patch/paint repair


Featured Posts

A nasty case of localised rust has broken out on my other boat. 

How would the team advise going about repairing it, please?? Most of the paintwork is fine. Just two or free serious rust patches of which this is the worst.

Many thanks!

 

IMG_2135 (1).JPG

Link to comment
Share on other sites

I would sand the paint back until you have exposed all the rust and then treat with accustomed converter, prime and paint.  When I started that approach on our boat the problem I found was what appeared as a few inches of rust was much bigger once the paint was removed.  In the end I gave up and paid someone else for a full repaint.

Link to comment
Share on other sites

1 minute ago, mark99 said:

Needle gun, powerbrush off rust. Treat rust. You may be looking at filler to get smooth surface back. 

 

Thanks for answers so far. Vactan doesn't last more than a couple of years in my experience before rust breaks through again. Perhaps I should read the instructions again.

A needle gun sounds a good idea. A pneumatic needle gun? Or are electric ones around these days?

I'm reluctant to get a full repaint as the lettering is rather good and I don't want to loose it...

Link to comment
Share on other sites

I reckon if you dont have confidence in rust treaters its best to get right back to new bright metal with no rust showing and do away with treater. Harder to do cos of complex shapes but if/ once done prime / ucoat asap. Flapdisks, needle gun, power cup brush power wheel brush... I used sometimes the little mouse sanders for a fine flatish finish.

Me and my mooring neighbours are doing our roofs this year. One had good result with vactan the other it rerusted straight away.

 

 

 

Edited by mark99
Link to comment
Share on other sites

15 minutes ago, Mike the Boilerman said:

Vactan doesn't last more than a couple of years in my experience before rust breaks through again.

Yes, it needs to have a top coat if you want it to last for years. It's only a latex primer (as well as a rust converter of course). 

Link to comment
Share on other sites

I routinely treat spots of rust and cruising damage. The low gunwales on Vulpes seem to take quite a hammering and are routinely touched up but I have also done the front and rear decks, all of the cants and the roof. Every piece of steel that can be seen in plan on the boat has been treated and painted by me.

Whererever possible I strip back to bright metal. I often do this with just hand tools as I don't have power at my home mooring. It looks like this will end up as a big patch and being on the cabin side (I think) it will need some care with the tools.

Next I always treat with a commonly available rust treatment. I don't go overboard on the product because I think the benefit of treatment mostly comes from the prep work and not the treatment. I suspect those who think rust treatments don't work are expecting them to perform miracles instead of doing the hard graft themselves. Given the size and location here it might be wise to use a high spec product but may depend on how you get on removing the rust.

Then I prime followed by painting with at least one coat each of Interntional Prekote and Toplac.

The key for me is that the boat wears its history. To the eye it's made of metal and it's lived a bit. It's well presented but pristine it certainly isn't. Brushmarks are part of that although I do make efforts to lay off the paint as well as I can. I see new boats with smooth steel work and shiny black spray painted gunwales. To my eye they could be made of plastic.

The hardest thing will probably be to get a colour match to the paint as I suspect it will end up being a pretty large patch when the rust and flaking paint is fully removed.

JP

Edited by Captain Pegg
  • Greenie 1
Link to comment
Share on other sites

1 hour ago, WotEver said:

Yes, it needs to have a top coat if you want it to last for years. It's only a latex primer (as well as a rust converter of course). 

Yes I appreciate that. I meant after promptly painting over vactan in accordance with the instructions, rust seems to break through again in a couple of years. 

Link to comment
Share on other sites

2 minutes ago, Mike the Boilerman said:

Yes I appreciate that. I meant after promptly painting over vactan in accordance with the instructions, rust seems to break through again in a couple of years. 

Ohh... I've not had that. 

Link to comment
Share on other sites

9 minutes ago, WotEver said:

Ohh... I've not had that. 

 

I've probably expected too much from it, by actually believing it 'converts' rust into something else. I used it on the rusty base of my gas locker. Thoroughly sraped off all loose rust then applied it liberally.  Then danboline on top and now rust is breaking through all over. 

It wets the rust marvolously and dries black, so I thought it was doing something magical but you say it is just a latex layer?

Link to comment
Share on other sites

How I do it:

Remove the rust as far as possible with a dished (not cup)  twist knot wire brush in an angel grinder, getting to non-rusty bare metal all round the patch.   Feather the edges of the paint either by hand or with a DA and a 120 grit disc.

Apply Fertan iaw instructions.  ( Be sure to scrub  it off well before priming).   Fill any pits with P38 or similar.  Prime,  2 coats undercoat and 2 coats  gloss.  Feather the edges with 1200 grit wet and dry used wet or a maroon hand pad used wet .  Wash Off.  Polish up with Farecla G3 and G10 on a blue sponge mop  then finish with a good paste wax.

 

Looking at your picky I reckon that patch is going to be quite big by the time you get to the edges of the rust.  You might find yourself right down by the cream stripe. It also looks like it would benefit from at least 2 Fertan treatments, after the wire brush.  Several dry windless days required!

 

N

Link to comment
Share on other sites

6 minutes ago, Mike the Boilerman said:

 

I've probably expected too much from it, by actually believing it 'converts' rust into something else. I used it on the rusty base of my gas locker. Thoroughly sraped off all loose rust then applied it liberally.  Then danboline on top and now rust is breaking through all over. 

It wets the rust marvolously and dries black, so I thought it was doing something magical but you say it is just a latex layer?

It converts the Ferrous Oxide into Phosphoric Oxide but will not treat anything other than the surface layer. It's best to get back to almost bright metal and then treat the remaining rust. The latex is just a carrier for the Phosphoric Acid component and when dry prevents moisture attacking any bright steel plus it is very good at accepting a coat of paint

Phil

Link to comment
Share on other sites

4 hours ago, Mike the Boilerman said:

A nasty case of localised rust has broken out on my other boat. 

How would the team advise going about repairing it, please?? Most of the paintwork is fine. Just two or free serious rust patches of which this is the worst.

Many thanks!

 

IMG_2135 (1).JPG

I would just scrape the worst off and prime it with Owatrol but if memory serves you don't rate Owatrol..?

 

Link to comment
Share on other sites

I agree with BEngo that if you are to remove paint back far enough to get to metal with no rusting you are likely to find the area is a lot larger than you might assume just looking at how it looks before you disturb it..

Link to comment
Share on other sites

The trick we have found with vactan is to take back to almost-clean metal with just surface rust, apply the vactan, wait a couple of weeks and a handful of spots will rust through where the rust was too thick. Clean these spots up a bit further and repeat. Once nothing further comes through, prime and paint.

Link to comment
Share on other sites

3 hours ago, Phil Ambrose said:

It converts the Ferrous Oxide into Phosphoric Oxide but will not treat anything other than the surface layer. It's best to get back to almost bright metal and then treat the remaining rust. The latex is just a carrier for the Phosphoric Acid component and when dry prevents moisture attacking any bright steel plus it is very good at accepting a coat of paint

Phil

 

47 minutes ago, Giant said:

The trick we have found with vactan is to take back to almost-clean metal with just surface rust, apply the vactan, wait a couple of weeks and a handful of spots will rust through where the rust was too thick. Clean these spots up a bit further and repeat. Once nothing further comes through, prime and paint.

^^^^ These :)

You can't leave thick rust and expect any treatment to get it all - it simply can't get to it all. 

Link to comment
Share on other sites

Get back to shiny metal, but it will almost certainly be two or three times worse/bigger than it looks. Hand sanding with course grit paper might just work, but if not a wire cup brush will likely do it. A few deeper pits can be tackled with a little grinding stone in a Dremmel (speaking from much personal experience here). If there is serious pitting then a needle gun would be a really good investment (for that gas locker floor too). Electric ones are very expensive and as you have land based storage a proper compressed air system would be a better investment.  If you can remove all the rust then forget the rust converters and go directly to a couple of coats of Bondaprimer. Once primed evaluate the level of pitting and decide if some body filler is required after giving serious consideration to the philosophy of captain Pegg.

If you go for a full repaint take pictures of the sign writing a find a good sign writer to replicate it.

............Dave

Link to comment
Share on other sites

Most good signwriters would flinch at being asked to replicate someone else's work....I may be wrong, but I think that the livery on Mike's boat was painted by someone I taught for a weekend, years ago, on one of my lettering courses. Signwriting is akin to handwriting, we all have an individualistic take on letters, making everyone's work recognisable, as opposed to perfect but soul- less computer cut vinyl.

Cheers! 

 

Dave

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.