Protecting the bilges and what can I do to the hull??

[LeonR]

Hey all, 

I've just a spent a week clearing this space in the bow of my dutch barge. There were 2 x m2 water tanks that must have been leaking for years. 

 

I was given a plan for prepping the 'walls' (or hull) in this case, which involves removing rust, vactan, prime and then gloss. My question is 2 fold, plus a bonus one - 

 

1. the walls/hull sides are completely corrosion free and they were behind mountains of rockwool and crappy cladding. Do I really need to follow all those steps? If it hasn't corroded in a 120 years?

 

2. The bilges were another story - 90% of rust removed so far. I heard another boat owner mention using oil to protect them, is that suitable? Or should I follow all those steps above? 

 

3. This is the 3rd time I have asked this question because I struggle to believe the answer is yes... Can I cut small portholes in the walls/hull without compromising the structural integrity? They would have to be small enough to fit in between the joins anyway. 

 

Thanks guys

[Jen-in-Wellies]

1 hour ago, LeonR said:

This is the 3rd time I have asked this question because I struggle to believe the answer is yes... Can I cut small portholes in the walls/hull without compromising the structural integrity? They would have to be small enough to fit in between the joins anyway. 

Yes for the fourth time. Portholes are round because they are least likely to act as stress concentrators and risk cracks forming. A lot of work in WWII on Liberty ships around this. It is also why airliner windows and other openings in the hull now have rounded corners.

What type of porthole are you planning to use? Proper sea going ones, or narrowboat style pretend ones? 0How far off the nominal water surface are these portholes going to be? If close to the water, or if the boat is going to be on lumpy water, then the portholes need to be strong and waterproof enough to cope, including the glass type and thickness.

[Tracy D'arth]

Do not oil bilges. I does no good and it will stink for ever.

[Tonka]

2 minutes ago, Tracy D'arth said:

Do not oil bilges. I does no good and it will stink for ever.

What about llanoguard like they use on cars

[Jen-in-Wellies]

3 minutes ago, Tonka said:

What about llanoguard like they use on cars

There are a lot of oils. The OP needs to be specific. Everything from the crude oil that tanker captains dump on sea birds, to olive oil. I suspect something specific for protecting steel, like your suggestion, but we don't know what the OP is thinking.

[Bee]

You really need to check out the Dutch Barge Association, more specific knowledge there. I wouldn't worry too much about the internal surfaces above the waterline. The area below the waterline is the important bit, there is a very good chance that the hull has been overplated to a greater or lesser degree so the surface that you are looking at from inside might not be the bit that is keeping the water out so a good clean and some sort of hull grease slathered over the bottom is probably your best bet. As for portholes It should be OK but be careful, Is that boat a Tjalk? there might not be a lot of freeboard when fitted out. Underwater portholes are not a great idea!

Edited December 15, 2023 by Bee

[mrsmelly]

When I bought my  new shell to fit out I bought a few gallons of Waxoyl. I heated it to thin it a little then sprayed it on the entire shell from gunwhale down and base plate. It sets ish but creeps to cover gaps. Did a great job of my shell anyway and quick to do. Dont know if its still available these days?

 

 

[Bee]

5 minutes ago, mrsmelly said:

When I bought my  new shell to fit out I bought a few gallons of Waxoyl. I heated it to thin it a little then sprayed it on the entire shell from gunwhale down and base plate. It sets ish but creeps to cover gaps. Did a great job of my shell anyway and quick to do. Dont know if its still available these days?

 

 

Don't know but Morris's of Shrewsbury do their version -Ankor wax. I used it on my Allegro. Still fell apart though

[Lily Rose]

7 minutes ago, mrsmelly said:

When I bought my  new shell to fit out I bought a few gallons of Waxoyl. I heated it to thin it a little then sprayed it on the entire shell from gunwhale down and base plate. It sets ish but creeps to cover gaps. Did a great job of my shell anyway and quick to do. Dont know if its still available these days?

 

 

 

 

If it was good It's now probably either unavailable or 're-formulated" to be much less effective. But you never know.

[Alan de Enfield]

40 minutes ago, Bee said:

Underwater portholes are not a great idea!

 

My Catamaran has 'under water portholes' (escape hatches actually) which is (was) an RCD requirement to allow egress if the boat is inverted.

They are pretty much on the water line but when whizzing along, the water level is halfway up and occasionally you get fish swimming past.

 

Left hand side of the picture below the end of the bed.

 

 

 

Edited December 15, 2023 by Alan de Enfield

[Jen-in-Wellies]

1 hour ago, Alan de Enfield said:

My Catamaran has 'under water portholes' (escape hatches actually) which is (was) an RCD requirement to allow egress if the boat is inverted.

They are pretty much on the water line but when whizzing along, the water level is halfway up and occasionally you get fish swimming past.

A catamaran's got a spare hull though, so if one sinks, you can still use the other one. 😀

[Alan de Enfield]

50 minutes ago, Jen-in-Wellies said:

A catamaran's got a spare hull though, so if one sinks, you can still use the other one. 😀

 

Thats the problem with a cat - neither of the hulls sink and it just sits inverted with a 70 foot long keel stopping it rolling 'right side up'

[Dav and Pen]

The inside of the hull and bottom of my Dutch barge-was covered with what the Dutch called Bilge grease a black grease which they applied when it was converted to a pleasure boat, it was certainly still there when we did some alterations.

[truckcab79]

5 hours ago, Lily Rose said:

 

 

If it was good It's now probably either unavailable or 're-formulated" to be much less effective. But you never know.

Waxoyl is still widely available and widely used.  Having used it in car projects for years it had crossed my mind to use it in my bilge / underfloor as it happens.  
 

If you do use it then it needs to be warmed and personally I prefer to warm it and dilute it slightly with white spirit.  Get yourself a decent compressor and a shultz gun to spray it though even the tiniest compressor will spray it well enough if you warm / dilute it enough.  Avoid the pump sprayers that they sell for application.  They’re rubbish and squirt it rather than atomise it. 

[magnetman]

The best way to look after the Bilges is to make sure they are dry. 

 

Be happy if there are spiders in there. 

 

 

 

 

[Jen-in-Wellies]

24 minutes ago, magnetman said:

The best way to look after the Bilges is to make sure they are dry. 

 

Be happy if there are spiders in there. 

 

 

 

 

It should be on the check list for any boat build, or rebuild project to make sure the spiders are installed.

[blackrose]

7 hours ago, magnetman said:

The best way to look after the Bilges is to make sure they are dry. 

 

Agreed. An occasional small leak into the bilges will dry out by itself without causing an issue, but if you think you're going to have continuous leaks from above and you can't keep the bilges dry then your very best solution is a few coats of a good epoxy paint. However for that you'd need to make sure you can remove all the rust and prep the steel to the required standards and it needs to be completely grease and dirt free prior to painting. I epoxied the bottoms of my stern lockers and gas locker at the bow about 6 years ago as there's no way to keep the water out and they were badly corroded from standing water. The water is still in them but now it's just like a puddle on a plastic tray.

 

Personally I think any greases or waxes are a waste of time because if the bilges stay dry you won't need a load of grease down there and if they stay wet for long enough that water will eventually get under whatever grease you've coated the bilges with. Then that grease becomes a pain because it's all got to be cleaned out in order to do the job properly.

[LeonR]

On 15/12/2023 at 08:35, Jen-in-Wellies said:

Yes for the fourth time. Portholes are round because they are least likely to act as stress concentrators and risk cracks forming. A lot of work in WWII on Liberty ships around this. It is also why airliner windows and other openings in the hull now have rounded corners.

What type of porthole are you planning to use? Proper sea going ones, or narrowboat style pretend ones? 0How far off the nominal water surface are these portholes going to be? If close to the water, or if the boat is going to be on lumpy water, then the portholes need to be strong and waterproof enough to cope, including the glass type and thickness.

Hey, thanks for the response. They would have to be small enough to fit between the joins so probs only 6 inche accounting for the frames etc. Almost a metre from the waterline. 

Thanks

 

On 16/12/2023 at 04:24, blackrose said:

 

Agreed. An occasional small leak into the bilges will dry out by itself without causing an issue, but if you think you're going to have continuous leaks from above and you can't keep the bilges dry then your very best solution is a few coats of a good epoxy paint. However for that you'd need to make sure you can remove all the rust and prep the steel to the required standards and it needs to be completely grease and dirt free prior to painting. I epoxied the bottoms of my stern lockers and gas locker at the bow about 6 years ago as there's no way to keep the water out and they were badly corroded from standing water. The water is still in them but now it's just like a puddle on a plastic tray.

 

Personally I think any greases or waxes are a waste of time because if the bilges stay dry you won't need a load of grease down there and if they stay wet for long enough that water will eventually get under whatever grease you've coated the bilges with. Then that grease becomes a pain because it's all got to be cleaned out in order to do the job properly.

Yep, this is all making sense. §i'm going to stick to the original idea - vactan, red oxide etc