to black the baseplate or not...

[Hannah and Jay]

that is the question? What have others done?

[Bimbly1]

that is the question? What have others done?

Not worth the effort IMHO. Blacking is soon be scraped off when touching/grinding the bottom of the cut. Anyway, the main area of corrosion is around the waterline, so I concentrate my efforts on the sides, down to the baseplate edges.

[matty40s]

Not something I can get done this year now,

my skoda has just come in for front wheel bearings(disintegrated), suspension widgets, steering rack somethings, and a few other bits. Thats my grand saved for blacking gone on the motor for it's MOT.

 

265000 miles on original everything inc starter batery ain't bad though.

[alan_fincher]

that is the question? What have others done?

You appear to have a Springer ?

 

So does it have a true flat base, or is it V bottomed like most of them are ?

 

I would have thought slightly different considerations apply on a V bottom boat to a flat bottomed one ?

 

Which leads me to another question, I'll ask here.....

 

In your sprayfoam question, if it does have a V bottom, shouldn't any water in the bilge, (and there shouldn't be any!), end up in the middle, not near the spray-foamed sides ?

[mayalld]

Not worth the effort IMHO. Blacking is soon be scraped off when touching/grinding the bottom of the cut.

 

What, ALL of it?

[matty40s]

He obviously tries to get up to Bewdley too often Dave.....

[Hannah and Jay]

You appear to have a Springer ?

 

So does it have a true flat base, or is it V bottomed like most of them are ?

 

I would have thought slightly different considerations apply on a V bottom boat to a flat bottomed one ?

 

Which leads me to another question, I'll ask here.....

 

In your sprayfoam question, if it does have a V bottom, shouldn't any water in the bilge, (and there shouldn't be any!), end up in the middle, not near the spray-foamed sides ?

 

Indeedy, we have a springer with a V bottom, does this make a difference to the baseplate blacking debate? Any yes, you are quite right about the sprayfoam Q, any water in bilges should go to the central V and not anywhere near the sprayfoam, there would have to be A LOT of water in our bilge to affect the insulation!

[boots]

I believe there are a lot of boats out there that have never had the bottom blacked, and yet don't seem to hear of many needing repairs to the baseplate. There are some, but the majority seems to be to the sides (which are usually treated). This suggests there is something in the argument that you don't need to have it done.

 

Our boat is 4 years old, and when we had it surveyed last year - there was no significant corrosion on the baseplate which had never been painted. Never-the-less, we did have it blacked - on the basis that it wasn't going to do any harm! Also, when looking for a boat we did find one (that we wanted to buy) but walked away after the surveyor advised that repairs to the baseplate would be needed in the next few years - though if I recall the boat was already 30+ years old and the suggestion was the corrosion had been due to 'galvanic' action (the sides had already been over-plated).

 

Not sure if that adds anything, but that has been our experience.

 

Martin

[canaldrifter]

Another argument against blacking the base plate is that corrosion due to elecrolysis could occur in the location of the first scratch instead of evenly spread over the whole plate.

 

Tone

[mikevye]

Another argument against blacking the base plate is that corrosion due to elecrolysis could occur in the location of the first scratch instead of evenly spread over the whole plate.

 

Tone

 

V good point, even worse if a bubble formed!

[furnessvale]

that is the question? What have others done?

 

The simple answer is to look at your bottom when in dry dock (no dirty remarks please:-)

If it is shiny then you would be wasting your time as the blacking would be scraped off when next in the water. If however your bottom is rusty that would indicate that you do not ground on a regular basis and blacking could be beneficial.

 

George ex nb Alton retired

[twbm]

One thing to remember is that if you do decide to go ahead, to do a proper job you'll need to refloat the boat and move it a foot to get at the bits that are sitting on the blocks, or prop the boat up and remove them.

[canaldrifter]

One thing to remember is that if you do decide to go ahead, to do a proper job you'll need to refloat the boat and move it a foot to get at the bits that are sitting on the blocks, or prop the boat up and remove them.

 

Personally, I wouldn't bother blacking the bottom plate at all. Similarly fitting anodes.

 

Tone

[Dorman]

Another argument against blacking the base plate is that corrosion due to elecrolysis could occur in the location of the first scratch instead of evenly spread over the whole plate.

 

Tone

 

Agreed

 

Amazon is shiny on the two occassions we have blacked (epoxy) the sides so have not touched and no pitting seen. Interestingly when we bought it the front was still 12mm but the back was down to 11.5 due to dragging--little point l thought to paint if steel is being worn away. On my calculations be down to 1mm 100 years at that rate!!

[Ewart Hodgson]

that is the question? What have others done?

Well... if I can raise a dissenting voice... I have always blacked the bottom. Except at the very edges, where paint is sometimes scraped off, and at the bottom of the skeg (mirror-shine), I find that almost all of the paint (bitumen) is still there after 3 years, and that's on the Llangollen, not famed for being the deepest waterway. If you are new to boating, you may see more scrapes in the first few months, but when you have the hang of letting the boat feel for the channel, you will be amazed at how little damage is done to the bottom plate paint.

 

As well as using a pressure washer, I use a garden hoe to scrape the weed and shellfish off (yes, really!), then when all is dry, I duck tape a paint roller to the end of the hoe and paint it that way. A bit messy but not impossible.

 

I also replace the anodes, every time. With anodes, a scratch will be well protected (and you can see it works - all but very recent scratches, still shiny steel, become 'anode-coloured').

 

Why? My boat is many decades old and was built with steel only 1/4 inch thick (roughly 6mm) even on the bottom. On the plus side, with this painting it has remained 6mm thick except right at the outer edges, where two small sections at the turn of the bow have had to be over-plated ('under-plated' may be a more descriptive term). I think these are the places that meet the shallows first when if I am coming in to moor.

 

It seems bizarre to me not to do this. (But then, I touch up the paint under my cars every year too, which is probably why they are still fine after 21 and 35 years respectively. I reckon that 2 hours doing that is far less hassle than buying a new vehicle. Similarly, messing about with a hoe is much easier and more pleasant than replating your hull...).

[kienik]

i have a Springer and so do a few other fellow moorers at the farm, we have all took the decision to black the "V" , the reason being that, all of the springers ive seen out of the water do look slightly pitted and rusty on the "V", so i would say yes definately black the "V" on your boat.

 

Nik

[blackrose]

Another argument against blacking the base plate is that corrosion due to elecrolysis could occur in the location of the first scratch instead of evenly spread over the whole plate.

 

Tone

 

I'm not sure whoever came up with that argument thought it through? Surely the same could be said about a scratch in the blacking on the sides of the boat, but we still paint the sides.

 

In general I think that the more paint you can get on a hull the better. There's no real argument against painting the baseplate apart from time and money. The fact is that it's difficult so it often isn't done. When my 2005 boat came out the water after a year I was alarmed to see rust on the unpainted baseplate and I planned to paint it the next time it came out.

 

 

However, when it came out the water last summer it looked no worse than 4 years earlier, and when I got underneath to have a look I found that the rust was very superficial and I could almost brush it off with my hand. So it seems that if you have a boat with a good thick baseplate (mine is 10mm), it's probably not worth worrying unduly about it.

Edited February 19, 2011 by blackrose

[Guest]

I'm not sure whoever came up with that argument thought it through? Surely the same could be said about a scratch in the blacking on the sides of the boat, but we still paint the sides.

 

In general I think that the more paint you can get on a hull the better. There's no real argument against painting the baseplate apart from time and money. The fact is that it's difficult so it often isn't done. When my 2005 boat came out the water after a year I was alarmed to see rust on the unpainted baseplate and I planned to paint it the next time it came out.

 

 

However, when it came out the water last summer it looked no worse than 4 years earlier, and when I got underneath to have a look I found that the rust was very superficial and I could almost brush it off with my hand. So it seems that if you have a boat with a good thick baseplate (mine is 10mm), it's probably not worth worrying unduly about it.

I suspect that the 10mm baseplate will probably outlast you, unless it is subject to abuse from say an electrical leak or similar. Many boats with 6mm baseplates from days gone by are still healthy, my previous boat being an example.

[canaldrifter]

I'm not sure whoever came up with that argument thought it through? Surely the same could be said about a scratch in the blacking on the sides of the boat, but we still paint the sides.

 

 

 

If the base plate isn't blacked, then a scratch on the side below the waterline wouldn't be the first bit of uninsulated hull, would it?

 

Tone

[blackrose]

If the base plate isn't blacked, then a scratch on the side below the waterline wouldn't be the first bit of uninsulated hull, would it?

 

Tone

 

No it wouldn't, but if you're saying that steel boats should always have an underwater section that's left unpainted so that any scratches in the underwater sections that are painted won't be the first to be exposed, then I would say that's a logical black hole. If it were true then why would so many non-canal steel vessels have completely painted hulls? Using a section of unpainted steel hull to provide some sort of sacrificial protection to the rest of the hull doesn't make sense to me - that's what exposed anodes made of metals higher placed in the galvanic series are for surely?

 

I've has scratches in the underwater blacking on the sides of my boat and they've gone rusty. I'm reluctant to believe that they would have gone more rusty had my baseplate been painted.

Edited February 19, 2011 by blackrose

[canaldrifter]

If it were true then why would so many non-canal steel vessels have completely painted hulls?

 

Because they don't bounce along the bottom and they need anti-fouling paint.

 

Tone

Edited February 19, 2011 by canaldrifter

[blackrose]

Because they don't bounce along the bottom and they need anti-fouling paint.

 

Tone

 

I've never bounced along the bottom? I guess it depends which waterways you're on. But anyway, not painting the baseplate because it may scrape the bottom is a different argument than the one you originally posted.

 

It's not only seagoing boats that have completely painted hulls. I'm working on a steel Thames steam launch which is about 80' x 14'. The hull is completely painted with twin pack epoxy.

Edited February 20, 2011 by blackrose

[canaldrifter]

I've never bounced along the bottom? I guess it depends which waterways you're on. But anyway, not painting the baseplate because it may scrape the bottom is a different argument than the one you originally posted.

 

It's not only seagoing boats that have completely painted hulls. I'm working on a steel Thames steam launch which is about 80' x 14'. The hull is completely painted with twin pack epoxy.

 

I've read back in the thread and I can't follow the logic of your argument. Sorry.

 

But it does seem that the majority who have contributed to this thread agree with me.

 

Thus we must agree to differ.

 

Paint on. I'll go paint off.

 

Tone

[Chertsey]

Most boats requiring overplating on their bottoms have rotted from the inside rather than the outside. More important to pay attention to protecting the bilges.

[blackrose]

I've read back in the thread and I can't follow the logic of your argument. Sorry.

 

But it does seem that the majority who have contributed to this thread agree with me.

 

Thus we must agree to differ.

 

Paint on. I'll go paint off.

 

Tone

 

It's not that difficult to follow. The logic of my argument is that the more paint you can get onto a hull the better. There are many steel freshwater boats that have completely painted hulls and there's no reason not completely paint a hull on the basis of your reasoning that it will render any scratches in the sides of the boat more susceptable to rust. The majority here have unpainted baseplates (as do I), but that doesn't mean the majority here agrees with your argument. As I said previously, the main reason that most of us don't paint out baseplates is simply that it's difficult to do.

Edited February 21, 2011 by blackrose