Bubbling paintwork around portholes

[kryspduck]

Got a bit of maintenance to do around a couple of portholes.

 

Have some paint bubbling around the frame of the portholes which I assume means that there's rust lurking underneath.

 

It it recommended to remove the portholes remove old paint, remove rust and repaint?

 

I've got two left feet for hands and I'm a tad worried that I'll make a complete mess of things and make an undesirable situation far, far worse. The portholes have rivets, don't know what size, how to remove, how to re-fit, how to seal portholes so they don't leak etc.

 

Is it ever recommended to 'do a quick fix' by removing bubbling paint, remove worst of rust and repaint whilst portholes are still insitu?

 

ANY advice would be much appreciated.

[bottle]

 

Is it ever recommended to 'do a quick fix' by removing bubbling paint, remove worst of rust and repaint whilst portholes are still insitu?

 

No, not really it will be OK possibly for a year, the best way is as you detailed remove, treat, and paint.

[Rickent]

Ther will be water getting behind the frame , hence the rust so will need re sealing as well.

[Bloomsberry]

If you want information on any DIY job then have a search on youtube.

 

There's usually loads of videos that will show you how to do most things.

 

I painted my boat last year based on some videos on youtube and very good they were too.

[Mike Tee]

And after removing, prep and before painting, tap the holes so they will be easier to remove in the future

[Sea Dog]

I painted my boat last year based on some videos on youtube and very good they were too.

You did read the OP's statement that he has "2 left feet for hands", didn't you?

[dmr]

Is it ever recommended to 'do a quick fix' by removing bubbling paint, remove worst of rust and repaint whilst portholes are still insitu?

 

ANY advice would be much appreciated.

 

Yes, that's much better than doing nothing at all, but not nearly as good as doing the job properly. It will significantly slow down the spreading of the rust, but most likely will not stop the rusting from slowly getting deeper behind the port-hole. A small grinding stone in a Dremmel will allow you to remove the visible rust right back to bare metal, then carefully prime and paint. Can you trust yourself with a Dremmel? much less potential for big diy disasters than an angle grinder!!!!

 

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

[kryspduck]

Have multi-tool 'Dremmel' type device, will investigate possibility of bodge job until next Spring/ Summer or at least until I find the type of rivets used in the windows and a weather window long enough to do the job properly.

[nicknorman]

Have multi-tool 'Dremmel' type device, will investigate possibility of bodge job until next Spring/ Summer or at least until I find the type of rivets used in the windows and a weather window long enough to do the job properly.

If you haven't used rivets before they can perhaps seem a bit daunting but they are in fact easy to use. The way to find out what rivets are used at the moment is to drill the heads off them and then remove the window and push the headless rivets through. If you aren't planning to remove the window trim I guess they will fall inside the boat but I don't suppose it matters. Then you can measure the hole diameter and the thickness (frame thickness + sealant + cabin side thickness) - but of course the actual new rivet has to be considerably longer than that to allow it to grip. Rivets normally mention a max and min grip thickness which be quite a bit less than the rivet length - in other words you need rivets quite a bit longer than the thickness sum above. For example a 4.8mm dia 14mm pop rivet has a grip range of perhaps 8 to 10mm. Rivet diameters seem a bit funny (decimals of a mm) but that is a hang-up from imperial sizes.

 

You would probably be best to get sealed rivets that won't allow any water through the mandrel hole.

 

Or you could switch to screws as mentioned, they have the advantage that you can tighten them a bit as the sealant beds in.

Edited August 4, 2016 by nicknorman

[Guest]

If you haven't used rivets before they can perhaps seem a bit daunting but they are in fact easy to use. The way to find out what rivets are used at the moment is to drill the heads off them and then remove the window and push the headless rivets through. If you aren't planning to remove the window trim I guess they will fall inside the boat but I don't suppose it matters. Then you can measure the hole diameter and the thickness (frame thickness + sealant + cabin side thickness) - but of course the actual new rivet has to be considerably longer than that to allow it to grip. Rivets normally mention a max and min grip thickness which be quite a bit less than the rivet length - in other words you need rivets quite a bit longer than the thickness sum above. For example a 4.8mm dia 14mm pop rivet has a grip range of perhaps 8 to 10mm. Rivet diameters seem a bit funny (decimals of a mm) but that is a hang-up from imperial sizes.

 

You would probably be best to get sealed rivets that won't allow any water through the mandrel hole.

 

Or you could switch to screws as mentioned, they have the advantage that you can tighten them a bit as the sealant beds in.

I like screws best since the tightening torque is controllable. It is possible to over tighten on some window types, which can lead to further leaks. Pop rivets are not as controllable, and a PITA at further maintenance tasks.

[Odana]

Slightly off-topic (though it may help the OP if he decides not to remove porthole...

 

We have the same problem but really can't remove frames easily as we have the kind that have no screws on outside - I think they have clips to the inside of the hull but of course someone built woodwork over, so they can only be removed by removing all internal frames first. And the internal frames are not designed to be removed...

 

So what is the best way of rust-sealing and painting to minimise spread of further rust from underneath? I was thinking sand right back, attack as far under frame as possible with thin wire brush, then vactan or owatrol into crack, then loads of sealant or Captain Tolleys. Then paint.

[kryspduck]

Thanks for all the advice peeps, going to remove the windows over the next month or so, remove rust properly and repaint.

[WotEver]

Slightly off-topic (though it may help the OP if he decides not to remove porthole...

 

We have the same problem but really can't remove frames easily as we have the kind that have no screws on outside - I think they have clips to the inside of the hull but of course someone built woodwork over, so they can only be removed by removing all internal frames first. And the internal frames are not designed to be removed...

 

So what is the best way of rust-sealing and painting to minimise spread of further rust from underneath? I was thinking sand right back, attack as far under frame as possible with thin wire brush, then vactan or owatrol into crack, then loads of sealant or Captain Tolleys. Then paint.

What you describe sounds good to me. I'd really flood the gap behind the frames with Owatrol and keep adding it until you can't get any more to soak in. Then seal the gap with Marineflex. Hopefully this would keep moisture out for a substantial time.

 

Tony

 

Edited to remove autocorrect of Marineflex.

Edited August 5, 2016 by WotEver