Replating the bottom

[chris63]

i know this is a long way off but what are your thoughts on treating the floor (inside) i was thinking on the lines of a acid based rust eater then waxoil.

[bottle]

Water leaks.

 

and all the space under my floor is taken up with ballast.

[cereal tiller]

i know this is a long way off but what are your thoughts on treating the floor (inside) i was thinking on the lines of a acid based rust eater then waxoil.

My Boat had a Waxoyl coating on the base plate

 

It was not effective.

 

CT

[Alan de Enfield]

That could be positive then didn't realise that that much rust would create such a thin layer of actual steel, not going to start prodding though until it's out of the water!!

 

.......... that that much rust would be created by so little steel loss...............

[RLWP]

i know this is a long way off but what are your thoughts on treating the floor (inside) i was thinking on the lines of a acid based rust eater then waxoil.

 

I would use a rust treatment then paint

 

Richard

[Paul G2]

Check thickness thoroughly before you decide to replate.

 

Am currently replacing flooring in my boat and Sprayfoaming the Baseplate

 

When this boat was constructed no insulation was placed on the baseplate as I was led to believe that it was common practise to omit it.

 

Considerable rusting has occurred and the thickness of removable material looked alarming!

 

A Phosphoric acid solution has been applied after thorough preparation,followed shortly after by 25 MM of expanding 2 component Foam

 

I estimate that the original 10 MM plating is still over 9.6 MM thick,and that is after 18 years live aboard use.

 

The Welder on this job was myself and as an extra confirmation I studied the profiles of the welds in this area,their shape is hardly altered.

 

A competent Fabricator would likely give any suspicious areas a good Resounding blow from a Ball Pein hammer and if there is still doubt a pilot drill would confirm actual remaining steel thickness.

 

Only another 60 feet to go!

 

E.T.A. the distance between the top of the transverse 80 MM Angle stiffeners was measured with a Vernier Caliper which confirmed the 0.4 MM loss of material.

CT

If your bilge rusted it is because your bilge got wet. Apparently you are assuming the moisture was all condensation. What if it was not?

 

I've never heard of anyone putting spray foam in the bilge before. That sounds like it is just asking for trouble and that you will end up with a bilge full of smelly, waterlogged spray foam.

 

Judging from your posts you seem like a pretty competent and conscientious fellow, but I really wonder if you have thought this particular decision all the way through. Paint is by far the most common product that is applied to bilges.

 

At the rate your steel is rusting, after 100 years the boat will still have 7.78mm left, and you'll be too dead to care if it doesn't, so it seems like the sprayfoam is kind of an over reaction to a non-existent problem.

[cereal tiller]

If your bilge rusted it is because your bilge got wet. Apparently you are assuming the moisture was all condensation. What if it was not?

 

I've never heard of anyone putting spray foam in the bilge before. That sounds like it is just asking for trouble and that you will end up with a bilge full of smelly, waterlogged spray foam.

 

Judging from your posts you seem like a pretty competent and conscientious fellow, but I really wonder if you have thought this particular decision all the way through. Paint is by far the most common product that is applied to bilges.

 

At the rate your steel is rusting, after 100 years the boat will still have 7.78mm left, and you'll be too dead to care if it doesn't, so it seems like the sprayfoam is kind of an over reaction to a non-existent problem.

Good observation Paul

 

The moisture was down to condensation

 

Have worked in boat construction/design repair for several decades,primarily as an Engineer,am not well seasoned with canalboats

 

I do consider that standard methods of narrowboat construction do not allow sufficient access to bilges.

 

As the new ply flooring is laid it will have inspection hatches Everywhere as is common practice in high standard boat builds.

 

Adequate and positive ventilation will be incorporated into the underfloor area also.

 

As other posters have already mentioned,2 pack foam is for water proofing.

 

after foaming the first section under the Bow deck I deliberately left a small section bare to see what would occur.

 

A substantial amount of water dripped off it!

 

Another major factor is loss of heat from the acomodationhave monitored temperature and humidity levels in original and renewed areas.

 

The improvement is impressive,to say the least!

 

CT

[Southern Star]

Of course all in surfers have their own requirements but don't believe MTB's bullshit either.

Totally uncalled for. I don't always agree with him, but MtB has been a source of help ever since I joined this forum.

 

You have six posts to your name. Who TF are you?

[Paul G2]

Good observation Paul

 

The moisture was down to condensation

 

Have worked in boat construction/design repair for several decades,primarily as an Engineer,am not well seasoned with canalboats

 

I do consider that standard methods of narrowboat construction do not allow sufficient access to bilges.

 

As the new ply flooring is laid it will have inspection hatches Everywhere as is common practice in high standard boat builds.

 

Adequate and positive ventilation will be incorporated into the underfloor area also.

 

As other posters have already mentioned,2 pack foam is for water proofing.

 

after foaming the first section under the Bow deck I deliberately left a small section bare to see what would occur.

 

A substantial amount of water dripped off it!

 

Another major factor is loss of heat from the acomodationhave monitored temperature and humidity levels in original and renewed areas.

 

The improvement is impressive,to say the least!

 

CT

 

I didn't know 2-pack foam was waterproof.

 

As I said originally, you have always seemed competent and conscientious, and it does appear you have thought this through. It will be interesting to see how the application holds up over time. Good luck!

[cereal tiller]

 

I didn't know 2-pack foam was waterproof.

 

As I said originally, you have always seemed competent and conscientious, and it does appear you have thought this through. It will be interesting to see how the application holds up over time. Good luck!

i spoke to a chap that uses class 1 foam commercially,he informed me that it is used as a lining for boat water tanks,so it is safe to assume that it is a suitable material for aquatic environments in general.

 

CT

[magnetman]

Totally uncalled for. I don't always agree with him, but MtB has been a source of help ever since I joined this forum.

 

You have six posts to your name. Who TF are you?

A surveyor?

 

I now want to see the text of a canal boat insurance policy requiring minimum thickness where the policyholder has -never- been asked for a hull survey/bottom report by the insurance company.

 

I know 4mm is seen as a minimum requirement however a lot of older boats may be insured.3rd party anyway and it makes a difference (to me) if the boat is a bean tin to start with or a classy boat.

 

If it was a 1960's Allens boat, for example, i'd probably do 6mm cut and fill replating to renew it but if it were a 1970s springer 3 or 4mm would extend its life a bit.

 

All imo

[Rickent]

Totally uncalled for. I don't always agree with him, but MtB has been a source of help ever since I joined this forum.

 

 

 

 

 

Agree.

uncalled for and not very nice......!!!

You have six posts to your name. Who TF are you?