How to Paint rusty piles

[DPH]

I've got 4 steel posts/piles on my drying mooring, the piles are in good condition but have got quite rusty.

Should I apply a rust convertor first, or can I get away with a direct to metal paint.

Would appreciate advice on the best way to go about this.

Thanks

 

[Daydream believer]

Would you not be better just leaving them as most decorative products would be just that. Decorative

 

[Bouba]

What ever you choose…use fast drying

 

[rogerthebodger]

I would grind any loose rust then paint with epoxy tar

Are the piles hollow or filled with something like concrete

 

[andsarkit]

Whatever you do, don't be tempted to use this paint. Absolute rubbish as I found out.

It is water based and when you put water on bare steel it rusts and the rust bleeds through. It might just work on a hot day when it dries very quickly but in winter it causes significant rusting before it dries.

 

[Praxinoscope]

Not sure I would go to the extent of painting them, whatever you use the rust will come back, just live with it.

 

[WoodyP]

https://www.ultrimaxstore.com/paint/maintenance-coatings/black-bitumen-paint.bit005

 

[AntarcticPilot]

Anything you apply has to resist the friction where the pontoon slides up and down the pile; there are usually rollers. I can't imagine any paint lasting more than a few months at most under those circumstances. The piles on every marina I've been in are simply allowed to get a nice rusty patina!

 

[DPH]

I would grind any loose rust then paint with epoxy tar

Are the piles hollow or filled with something like concrete

The piles are hollow.

 

[FinesseChris]

The piles are hollow.

...then beware.

One of the hollow piles I tied up to for 21 years snapped in half. After I'd left the mooring, thank goodness: the idea of 6 feet of 10-inch pipe dropping on my deck is not fun to contemplate. Luckily for the new tenant, it fell outwards, causing a pretty big splash.

Looked solid on the outside, but clearly not....

 

[Bouba]

https://www.ultrimaxstore.com/paint/maintenance-coatings/black-bitumen-paint.bit005

Will the bitumen get messy when the pylon is in use ?

 

[rogerthebodger]

If its hollow I would put some rebar down inside then fill it with concrete

If the pile is not sealed it will rust from the inside and snat at the water level as it will fill with salt water

Filling it with concrete will prevent this for quite fome time

 

[Stemar]

Now why did I think of Preparation H?

TBH, it'd probably be as effective as any treatment other than regerthebodger's suggestion.

 

[DPH]

If its hollow I would put some rebar down inside then fill it with concrete

If the pile is not sealed it will rust from the inside and snat at the water level as it will fill with salt water

Filling it with concrete will prevent this for quite fome time

The tops are sealed so no way of filling with concrete.
...but as they are sealed then there can't be any/much air(oxygen) inside so they shouldn't rust internally.

 

[rogerthebodger]

The tops are sealed so no way of filling with concrete.
...but as they are sealed then there can't be any/much air(oxygen) inside so they shouldn't rust internally.

True as long as the bottom is also sealed and no change of air can take place

The hollow steel rudder of my steel boat is sealed and filled with oud engine oil so it there is any leak I can see it straight away

I would do a pressure test to ensure it is sealed

 

[AntarcticPilot]

True as long as the botton is also sealed and no change of air can take place

If the pile is totally sealed, it will experience high buoyancy forces and would be liable to be dislodged easily.

 

[rogerthebodger]

If the pile is totally sealed, it will experience high buoyancy forces and would be liable to be dislodged easily.

True

That is another reason why I filled my rudder with oil to educe the buoyancy

My self steering servo rubber is Foam filled GRP and floats if not lacked down

 

[WoodyP]

Will the bitumen get messy when the pylon is in use ?

No idea, but it's the sort of stuff that I have used, but not in a marine setting. It was good stuff. I saw a woman in a dry suit painting the piles at Fairlie . She was covered in the stuff and so were the piles when she finished.

 

[FinesseChris]

If its hollow I would put some rebar down inside then fill it with concrete

If the pile is not sealed it will rust from the inside and snat at the water level as it will fill with salt water

Filling it with concrete will prevent this for quite fome time

"snap at the water level as it will fill with salt water"

exactly what happened to me! See 10 above

 

[rogerthebodger]

"snap at the water level as it will fill with salt water"

exactly what happened to me! See 10 above

As AntarcticPilot said

If its sealed it would tend to experience high buoyancy forces and would be liable to be dislodged easily.

I would investigate this to ensure long life