Steel boat, rust what paint primer converter?

[Travellingwithtoby]

Hi guys

Have got a lot of scale and rust to clean up, I have more time than money....

I can Tig, mig, and am learning stick and sending the bits away for checking until I am proficient enough to safely do my own structural repairs.

Best rust converter? (After loose stuff removed and possibly new bits welded on if need be)

I have 10 L of 2 pack enamel direct to metal paint from a friend, said was used for coating industrial machinery ? in tile red none the less!

I would like to know what have used, and how it has lasted/ stood up to the test of time!

I intend on getting her out of the water and cleaning below waterline to steel, repairing anything that needs doing and then copper coating. Again any advice appreciated!

Please please can this be a pretty argument free thread thank you!

 

[ryanroberts]

Vatcan is common on narrwboats Vactan - Performance Chemicals Ltd . Does the job, but it does is a lot quicker in warm weather.

 

[rogerthebodger]

Hi guys

Have got a lot of scale and rust to clean up, I have more time than money....

I can Tig, mig, and am learning stick and sending the bits away for checking until I am proficient enough to safely do my own structural repairs.

Best rust converter? (After loose stuff removed and possibly new bits welded on if need be)

I have 10 L of 2 pack enamel direct to metal paint from a friend, said was used for coating industrial machinery ? in tile red none the less!

I would like to know what have used, and how it has lasted/ stood up to the test of time!

I intend on getting her out of the water and cleaning below waterline to steel, repairing anything that needs doing and then copper coating. Again any advice appreciated!

Please please can this be a pretty argument free thread thank you!

The key to prevent rust coming back is to get the steel clear of ALL rust.

Rust converters only work on surface rust and you cannot ensure that all the rust as been converted.

Best is to grit blast (grit not sand which is too soft)

What I do is needle descale then paint with Hydrochloric acid until the surface is a uniform grey colour. Any black patches means Iron Oxide still exist.

Once you have a uniform grey paint with phosphoric acid which will give some protection and slow down flash rusting.

Then paint with whatever metal paint you wish. I use high build epoxy and if below the waterline I use epoxy tar for th best protection.

Some pic of my boat and rust repairs on the site in my signature.

Do remember rust never sleeps.

 

[vyv_cox]

Offshore oilfield structures are grit blasted, needle gunned where this is impractical. Paint systems are all epoxy, primer, mid coat, top coat. At least two coats of each, usually more.

This may be OTT for a boat but it gives an idea of the best solution. Definitely not just direct to metal top coat.

 

[Travellingwithtoby]

The key to prevent rust coming back is to get the steel clear of ALL rust.

Rust converters only work on surface rust and you cannot ensure that all the rust as been converted.

Best is to grit blast (grit not sand which is too soft)

What I do is needle descale then paint with Hydrochloric acid until the surface is a uniform grey colour. Any black patches means Iron Oxide still exist.

Once you have a uniform grey paint with phosphoric acid which will give some protection and slow down flash rusting.

Then paint with whatever metal paint you wish. I use high build epoxy and if below the waterline I use epoxy tar for th best protection.

Some pic of my boat and rust repairs on the site in my signature.

Do remember rust never sleeps.

So golden nuggets there! Thank you!

Whereas the cheapest place to buy hydrochloric acid and phosphorus acid?

What are the fumes like from them? (Do I need the air fed mask inside)

Obviously will look up safety sheets but it cant hurt to ask!

Will have a look ?

Offshore oilfield structures are grit blasted, needle gunned where this is impractical. Paint systems are all epoxy, primer, mid coat, top coat. At least two coats of each, usually more.

This may be OTT for a boat but it gives an idea of the best solution. Definitely not just direct to metal top coat.

Well OTT and me get along well Haha

So all epoxy based primer mid and top coats, after a good needle gun (I got no hope of grit blasting while living aboard!

Dont suppose you know any brands? Assuming one epoxy isn't the same as the next!

 

[Travellingwithtoby]

Vatcan is common on narrwboats Vactan - Performance Chemicals Ltd . Does the job, but it does is a lot quicker in warm weather.

These guys do loads of stuff! I feel like a total nerd now hahaha

 

[Travellingwithtoby]

The key to prevent rust coming back is to get the steel clear of ALL rust.

Rust converters only work on surface rust and you cannot ensure that all the rust as been converted.

Best is to grit blast (grit not sand which is too soft)

What I do is needle descale then paint with Hydrochloric acid until the surface is a uniform grey colour. Any black patches means Iron Oxide still exist.

Once you have a uniform grey paint with phosphoric acid which will give some protection and slow down flash rusting.

Then paint with whatever metal paint you wish. I use high build epoxy and if below the waterline I use epoxy tar for th best protection.

Some pic of my boat and rust repairs on the site in my signature.

Do remember rust never sleeps.

That is one heck of a boat!

 

[GHA]

Book for you... Metal boat maintenance-A do it yourself guide eBook: Fratcher, Scott: Amazon.co.uk: Kindle Store

Rogers method probably as good as any, and similar to one outlined in the book above when gritblasting not an option, which is often... . Wickes used to do phosphoric acid as 'grout film remover' or maybe ebay/amazon. I liked ameron sealer paint as first tie coat primer as it was designed for less than perfect preparation but haven't seen it in Europe for a while. I've not had great success with the one coat miracle cures, get clean as you can, phosphoric acid for tye rust still in the pores and lots coats epoxy. Then wait 10 years to see if it worked

 

[Adrian62]

We used to use Vactan on the offshore barges which worked well , fertan is also good and is used by a lot of landrover Owners which get a lot of abuse ,
The best paint that i have used is rust bullit but it is expensive ,we have painted many things with this including old classic cars and we live by the sea and everything is covered in salt water and after nearly 10 years no rust has reappeared .

 

[Neil]

I had a very rusty cast iron keel that I needed to deal with before I copper coated it. I used a rust converting epoxy EM121 from rust.co.uk. After the first year I was quite happy with it.; I had a few tiny specks of rust come through, presumably from pinholes. My problem was that I had a very short weather window to treat the keel and copper coat the hull before lift in, so I only gave it one coat. If I was doing it again I would scrape a thin layer of unthinned epoxy to fill in the depressions, then put on preferably two coats of thinned EM121.

"EM121 is a two component Epoxy paint composed of nanoscale corrosion protective pigments in short chain molecules with very low surface tension.
This allows the paint to flow into all of the pits and troughs on the steel's surface, ensuring a tough penetrating primary bond.
This is the best kind of bond you can get with a paint finish. The high build epoxy forms a super strong protective barrier over the corrosion inhibiting pigments that hug the steels surface Excellent penetration and adhesion within a high build coating equals exceptional mechanical strength.

EM121 Epoxy can be applied successfully over wire brush cleaned steel and still offers the same exceptional performance as coatings applied over blast cleaned steel. Its finish is as hard as iron but flexes with the steel."

EM121 EPOXY - Rust Proofing Paint

 

[SlowlyButSurely]

Hi guys

Have got a lot of scale and rust to clean up, I have more time than money....

I can Tig, mig, and am learning stick and sending the bits away for checking until I am proficient enough to safely do my own structural repairs.

Best rust converter? (After loose stuff removed and possibly new bits welded on if need be)

I have 10 L of 2 pack enamel direct to metal paint from a friend, said was used for coating industrial machinery ? in tile red none the less!

I would like to know what have used, and how it has lasted/ stood up to the test of time!

I intend on getting her out of the water and cleaning below waterline to steel, repairing anything that needs doing and then copper coating. Again any advice appreciated!

Please please can this be a pretty argument free thread thank you!

We use Jotun Jotamastic 90 epoxy and Jotun Pioner topcoat on our steel boat. We have found rust converters to be a complete waste of time in our experience. Give the guys at SML a ring, they will give sound advice.

SML Marine Paints - Marine Paint | Boat Paint | Antifouling | Accessories

Definitely read Scott Fratcher's book mentioned above.

D

 

[Travellingwithtoby]

We use Jotun Jotamastic 90 epoxy and Jotun Pioner topcoat on our steel boat. We have found rust converters to be a complete waste of time in our experience. Give the guys at SML a ring, they will give sound advice.

SML Marine Paints - Marine Paint | Boat Paint | Antifouling | Accessories

Definitely read Scott Fratcher's book mentioned above.

D

That's the 3rd person to tell me his book is good, pity as the amazon reviews make it sound bad! Will buy one now

Will give them a ring

Have just been looking at cheaper metal thickness gauges.... as most of my internal corrosion work will be done on the water it would be nice to get a reading as I work, even if its 5% off better than putting a needle gun through the hull when in a confined space?

 

[Travellingwithtoby]

Book for you... Metal boat maintenance-A do it yourself guide eBook: Fratcher, Scott: Amazon.co.uk: Kindle Store

Rogers method probably as good as any, and similar to one outlined in the book above when gritblasting not an option, which is often... . Wickes used to do phosphoric acid as 'grout film remover' or maybe ebay/amazon. I liked ameron sealer paint as first tie coat primer as it was designed for less than perfect preparation but haven't seen it in Europe for a while. I've not had great success with the one coat miracle cures, get clean as you can, phosphoric acid for tye rust still in the pores and lots coats epoxy. Then wait 10 years to see if it worked

Awesome thank you for all the info! Going to get a fresh notebook I think ?

We used to use Vactan on the offshore barges which worked well , fertan is also good and is used by a lot of landrover Owners which get a lot of abuse ,
The best paint that i have used is rust bullit but it is expensive ,we have painted many things with this including old classic cars and we live by the sea and everything is covered in salt water and after nearly 10 years no rust has reappeared .

Yes I'm looking to find something that will last as long as possible and survive the harshest conditions, have a dream when I'm more experienced of heading to the arctic ?

So I suppose the worst case is I do my best on a budget with coatings get away for the winter, work and save, sell my last big things and then put her in a boat yard that's agreeable with my doing all the work while I live aboard!

I had a very rusty cast iron keel that I needed to deal with before I copper coated it. I used a rust converting epoxy EM121 from rust.co.uk. After the first year I was quite happy with it.; I had a few tiny specks of rust come through, presumably from pinholes. My problem was that I had a very short weather window to treat the keel and copper coat the hull before lift in, so I only gave it one coat. If I was doing it again I would scrape a thin layer of unthinned epoxy to fill in the depressions, then put on preferably two coats of thinned EM121.

"EM121 is a two component Epoxy paint composed of nanoscale corrosion protective pigments in short chain molecules with very low surface tension.
This allows the paint to flow into all of the pits and troughs on the steel's surface, ensuring a tough penetrating primary bond.
This is the best kind of bond you can get with a paint finish. The high build epoxy forms a super strong protective barrier over the corrosion inhibiting pigments that hug the steels surface Excellent penetration and adhesion within a high build coating equals exceptional mechanical strength.

EM121 Epoxy can be applied successfully over wire brush cleaned steel and still offers the same exceptional performance as coatings applied over blast cleaned steel. Its finish is as hard as iron but flexes with the steel."

EM121 EPOXY - Rust Proofing Paint

Their are so many options it's almost mind boggling!

Did you mix your own coppercoat or purchase?

I'm wondering about using my airless sprayers to do the coats, I know that have been used for antifoul with great success!


I think the first thing I need is a compressor man enough for needle gun and air fed mask being in that confined space with goggle and a respirator will be horrible, my mask is a close fit.... hmm

Or a full face scuba mask if cheap enough!

Thanks so far guys loads of good advice!

 

[GHA]

Have just been looking at cheaper metal thickness gauges.... as most of my internal corrosion work will be done on the water it would be nice to get a reading as I work, even if its 5% off better than putting a needle gun through the hull when in a confined space?

A good ultra sound gauge is certainly nice to have if you have the cash, not sure about the cheaper ones though. As for inside - if it's dodgy, you'll know!! I go high end technical with the punch test - if it looks nasty, centre punch and give it a good wack with the big hammer. No hole then OK for a little while anyway
There was a mostly bickering thread not so long ago with some good bits hidden away - very briefly , want a steel boat to last then... nothing bolted to the hull, everything welded on with lots epoxy paint. No wood touching metal anywhere, it will rust. Inside easily taken apart so you can keep an eye on the bilges, which should be bone dry always. I've been paying the price recently for not following that advice

 

[vyv_cox]

This is a section copied from the Coppercoat preparation instructions. Note that they do not mention any rust conversion, SA2.5 surface finish means uniformly metallic grey, no black patches whatsoever.

Iron/Steel/Lead: Bare metal must be first coated with an appropriate two-pack epoxy primer prior to an application of Coppercoat. As is common with all epoxy coatings, it is important that the substrate to be coated is well prepared. All surfaces should be clean and free from oils, bacteria or algal growth and any previously applied single-pack paints or coating. For optimum performance, and where possible, surfaces should be blast cleaned to a minimum of Swedish Standard SA 2.5. Where blast cleaning is not possible, mechanical wire brushing and grinding should be used to achieve a similar standard of preparation. We would recommend applying approximately 500 microns of our 100% solids, solvent-free epoxy, Hycote 152 or the anti-corrosive epoxy GP120. This is normally achieved with 4 coats when applied by roller.

 

[Neil]

Awesome thank you for all the info! Going to get a fresh notebook I think ?


Yes I'm looking to find something that will last as long as possible and survive the harshest conditions, have a dream when I'm more experienced of heading to the arctic ?

So I suppose the worst case is I do my best on a budget with coatings get away for the winter, work and save, sell my last big things and then put her in a boat yard that's agreeable with my doing all the work while I live aboard!





Their are so many options it's almost mind boggling!

Did you mix your own coppercoat or purchase?

I'm wondering about using my airless sprayers to do the coats, I know that have been used for antifoul with great success!


I think the first thing I need is a compressor man enough for needle gun and air fed mask being in that confined space with goggle and a respirator will be horrible, my mask is a close fit.... hmm

Or a full face scuba mask if cheap enough!

Thanks so far guys loads of good advice!

I bought from Coppercoat to do myself

 

[Neil]

This is a section copied from the Coppercoat preparation instructions. Note that they do not mention any rust conversion, SA2.5 surface finish means uniformly metallic grey, no black patches whatsoever.

Iron/Steel/Lead: Bare metal must be first coated with an appropriate two-pack epoxy primer prior to an application of Coppercoat. As is common with all epoxy coatings, it is important that the substrate to be coated is well prepared. All surfaces should be clean and free from oils, bacteria or algal growth and any previously applied single-pack paints or coating. For optimum performance, and where possible, surfaces should be blast cleaned to a minimum of Swedish Standard SA 2.5. Where blast cleaning is not possible, mechanical wire brushing and grinding should be used to achieve a similar standard of preparation. We would recommend applying approximately 500 microns of our 100% solids, solvent-free epoxy, Hycote 152 or the anti-corrosive epoxy GP120. This is normally achieved with 4 coats when applied by roller.

In my conversations with Rust.co.uk and Coppercoat, rust conversion was a definite no-no; it wouldn't be a sound surface for the epoxy. The EM121 that I used has rust inhibitors in it and since it is a two part epoxy, is a suitable substrate for Coppercoat. If I'd had a long enough spell of warm dry weather, it would have been perfect. As it is, I've used a drill and HSS bit to drill out the pinholes and paint over with EM121 and then new copper coat over the top. We'll see next year (if we can get our boats off the hard and into the water, Covid-19 permitting )

 

[Vicarage]

That's the 3rd person to tell me his book is good, pity as the amazon reviews make it sound bad! Will buy one now

Will give them a ring

Have just been looking at cheaper metal thickness gauges.... as most of my internal corrosion work will be done on the water it would be nice to get a reading as I work, even if its 5% off better than putting a needle gun through the hull when in a confined space?

+1000 for SML. They're the only supplier I've dealt with for a long time who has actively talked me out of buying an expensive product and steered us to something cheaper and actually better suited to our needs. Before now I've just rung them up with a vague problem and they've been able to save me loads of time by succinctly recommending a coating schedule and in one case emailing over specific instructions for how to mix two products together in such a way as to give us the characteristics we needed.

I was trained to use "Fertan" after needle gunning and before paint, though I guess because I've never not used Fertan then I've no way of know exactly how much difference it makes..!

 

[Travellingwithtoby]

In my conversations with Rust.co.uk and Coppercoat, rust conversion was a definite no-no; it wouldn't be a sound surface for the epoxy. The EM121 that I used has rust inhibitors in it and since it is a two part epoxy, is a suitable substrate for Coppercoat. If I'd had a long enough spell of warm dry weather, it would have been perfect. As it is, I've used a drill and HSS bit to drill out the pinholes and paint over with EM121 and then new copper coat over the top. We'll see next year (if we can get our boats off the hard and into the water, Covid-19 permitting )

Well it looks like I may have to find somewhere to lift me out sooner than later, have got multiple patches that look like the paint just "fell"off just above and below the waterline there have been a good few logs going past so I think they have " broken off" a few rusty patches.

+1000 for SML. They're the only supplier I've dealt with for a long time who has actively talked me out of buying an expensive product and steered us to something cheaper and actually better suited to our needs. Before now I've just rung them up with a vague problem and they've been able to save me loads of time by succinctly recommending a coating schedule and in one case emailing over specific instructions for how to mix two products together in such a way as to give us the characteristics we needed.

I was trained to use "Fertan" after needle gunning and before paint, though I guess because I've never not used Fertan then I've no way of know exactly how much difference it makes..!

Yes it seems to be one name that pops up a lot more than others!

Have started writing down all the variations used to try and help guide me!

Thanks guys!