First time out of the water

[Mohsen]

Hi Everyone,
 

This month Im taking my boat out of the water, after 6 years in and Im looking to lean into the hub of knowledge and experience on here!

 

Firstly, blacking... the boat first entered the water in 2018, a new build with a MACROPOXY L524 put on by the boat builder and then supplemented, by me, with a compatible Sherwin Williams product, simply because I had the time to build up the paint whilst the boat was on hard standing. No, Im not sure what I will find when it comes out, so I guess I can only plan so far but... Are there any tips on prep, what tools to use, what coatings to use (ideally not bitumen) and if bitumen, why?

 

On recommendation the base plate was not painted when it was built, but I am going to paint it when it comes out. Again, any suggestions on prep and whether I should perhaps put bitumen on the base for ease and speed?

 

Lastly, are there any other things worth doing whilst the boat is out? Time to repack the stern gland, etc?

 

I'd appreciate any words of wisdom from the hive mind.

 

Many thanks, in advance  

[JungleJames]

What is a compatible product?

Will it allow a 2 pack epoxy over the top?

 

What happened to the base plate? Any shot blasting? Not that is matters much now.

 

Really you have shot yourself in the foot.

The base should be done in 2 pack epoxy for the best protection. Plus the fact the rest of the hull is.

So the base needs shot blasting to prepare it for 2 packing.

With that in mind, you may as well take the whole hull and base plate back to bare metal, and then either zinc coat before 2 packing, or use a zinc rich 2 pack.

 

Ching ching!!

 

Assuming you are not a dab hand with a shot blaster, you will likely have to leave it all in the hands of a reputable yard. Of which only 2 stand out, and I suspect they are fully booked for a while.

 

Of course, cheaper options are available, but the above is probably the best way of going. 

 

The question also stands- who recommended not painting the base? If it was the builder/ painter, then one starts wondering just how good the initial paint job was. So the above definitely stands. Start afresh and make sure.

 

 

[TandC]

Reading the above reply from JungleJames would be enough to send anyone new to boating or boat maintenance into a bit of a panic.

 

My advice would be - panic not!   There's hundreds and hundreds of boats out there that haven't had their baseplate painted with any protection.  There's nothing to really suggest that your boats now riddled with holes and is going down like the Titanic. 

 

The argument goes that the baseplate is exposed to less oxygen so it's less necessary.  

 

Yes, personally I'd have gone for it at the time, and yes, I'd have gone for the same epoxy as the sides... but by the same token, I also have a boat that has epoxy blacking that is now 11 years old and is as rock hard as the day it went on.  Many would say I should have had it re-done by now - but successive surveys have shown it wasn't needed/   

 

So just get it out, have it inspected go from there - don't take too much doom from the post above. 

 

 

[JungleJames]

I wasn't meaning to be a doom merchant, and certainly wasn't saying his boat is about to sink.

 

I was just saying by not getting it painted at the time, it now adds to the cost (remember, the OP himself wants to get it done now). Hence the 'ching ching' remark.

 

Am I wrong in what I say?

1- the base plate should preferably be shot blasted and 2 packed, the same as the hull sides already are (taking into account the OP now wants to paint it).

2- if you are blasting the base plate, you may as well go all the way and do the hull sides as well, especially as we don't know what the last coating was on the hull sides.

3- If taking it all back to bare metal, the best protection is to then get it zinc coated, or to use a zinc rich paint.

 

To me, it is all fairly obvious stuff.

 

Sorry if that is a bit beyond a DIY job with the shot blasting, but there is no harm in pointing out the best way of going.

 

But I will clarify- your boat is probably not about to sink, and earth will still exist as a planet. There, no doom merchant here.

 

 

 

 

 

 

[DShK]

Wire wheel on an angle grinder to key and remove any flaking paint, suitable primer over exposed metal, go back over with your 2 pack product.

 

As for the base plate. There's a lot of opinions about bitumen. Some I've heard say "it's better than 2 pack because it smears rather than chips" but I've also heard from reputable sources that "you might as well paint it with B&Q emulsion".

 

In my opinion, if you can easily get at the baseplate, there's no harm in painting it with bitumen, so why not?. I wouldn't panic either way. My sides are 2 pack, nothing on the baseplate. Boat is 15 years old, last survey was spotless (I've jinxed it now though haven't I?).

You can always keep an eye on the baseplate and if it starts to show pitting, have it shot blasted and 2 packed.

Edited May 2 by DShK

[BEngo]

Prep for sides:

 

Pressure wash, angle grinder with saucer type twist knot wire brush to take the greyness  off the surface.

Two pack.

 

Prep for baseplate:

 

Ideal World: Shot blast

Real world: pressure washer  at 200bar or more.  Wire brush when dry.

 

Unless it is shot blasted I would only use bitumen on the bottom.  Work it  well into the pits.

 

With epoxy all over 5 or 6 years between dockings is OK.  With bitumen I think that is too long an interval.  I would want to check every 3 or at most  4 years.

 

While out: 

Check the inside of the weed hatch and the inside of the rudder tube, at the waterline, for pitting.  Make sure you paint them inside.

Check the stern tube and bearing  for play. About every 10 years draw the tail shaft out and see how it is wearing where the gland packing runs.

Renew the gland packing.

Renew any worn out anodes.

Check the lower end of the rudder post and the cup in the skeg for wear.

Paint the tunnel bands.

Clear out any drains ( sink, shower etc.) while you can get at both ends.

 

 Take the fenders off and clean the rubbish out of them.

 

N

[David Mack]

1 minute ago, BEngo said:

Check the inside of the weed hatch and the inside of the rudder tube, at the waterline, for pitting.  Make sure you paint them inside.

And the inside of the bow thruster tube if you have one.

[Tracy D'arth]

The Sherwin Williams 2 pack will be sound, its one of the best around. So clean it off well so it is no longer grey and recoat with the same.

Baseplate needs grit blast and epoxy if you cannot get it in for the same with a first coat of hot zinc ( Debdale )

Or if you can't do that pressure wash and a couple of coats of bitumen will be better than nothing. 

[ditchcrawler]

20 hours ago, Mohsen said:

Hi Everyone,
 

This month Im taking my boat out of the water, after 6 years in and Im looking to lean into the hub of knowledge and experience on here!

 

Firstly, blacking... the boat first entered the water in 2018, a new build with a MACROPOXY L524 put on by the boat builder  

Looks good stuff

 

[Mohsen]

thank you everyone for all the great help so far. 

I was just thinking, if I find a defect in the paint work, perhaps where I have scraped into something how is it best to repair.

 

In my mind, I sand it back to bear metal and the surrounding area trying to feather it off so that I can build up coats to blend in. Then I apply several layers of two pack to get it to the same level as the undamaged coating. Is this right or am I missing something? Can you repair two pack coatings in this way?

 

[Tracy D'arth]

10 minutes ago, Mohsen said:

thank you everyone for all the great help so far. 

I was just thinking, if I find a defect in the paint work, perhaps where I have scraped into something how is it best to repair.

 

In my mind, I sand it back to bear metal and the surrounding area trying to feather it off so that I can build up coats to blend in. Then I apply several layers of two pack to get it to the same level as the undamaged coating. Is this right or am I missing something? Can you repair two pack coatings in this way?

 

Right enough but aiming for an optical finish in the hull 2 pack is a bit unnecessary

[Mohsen]

well it was more than if it looks right, I know ive probably done it right?

[blackrose]

On 02/05/2024 at 08:40, BEngo said:

Prep for sides:

 

Pressure wash, angle grinder with saucer type twist knot wire brush to take the greyness  off the surface.

Two pack.

 

I think a wire wheel on an angle grinder is a bit aggressive if you're just trying to give the surface of the existing epoxy a key. You'll end up going through to the steel. Plus it will take you forever to go around the whole boat with an angle grinder.

 

If after pressure washing the existing epoxy looks sound then all it needs is a key with a sander and a coarse grit paper, plus go over any rust patches with the wire wheel. If it's not sound it's all got to come off and that means blasting.

19 hours ago, Mohsen said:

In my mind, I sand it back to bear metal and the surrounding area trying to feather it off so that I can build up coats to blend in. Then I apply several layers of two pack to get it to the same level as the undamaged coating. Is this right or am I missing something? Can you repair two pack coatings in this way?

 

If you're still talking about the hull sides below rubbing strakes by all means feather the edges of any patches that have gone back to bare metal but don't bother trying to build up coats to the same level unless you have lots of time or are particularly precious about how the hull sides look. You must refer to the the technical data sheet for any epoxy you're using. Particularly important are the mixing ratios (easier by weight than volume with kitchen scales if the relative weights are given), mixing thoroughly and only then adding the correct thinners if required (10% max or according to TDS), minimum overcoating times and minimum time for service (back in the water).

[BEngo]

1 hour ago, blackrose said:

 

I think a wire wheel on an angle grinder is a bit aggressive if you're just trying to give the surface of the existing epoxy a key. You'll end up going through to the steel. Plus it will take you forever to go around the whole boat with an angle grinder.

You dont really need to push, even gently.   You can see you're doing it right  as the thin oxidised grey layer disappears and the 2 pack black shows.  If you are going through to the steel you are pushing far too hard.

 

The saucer wheel gives  the maximum coverage  ( bigger OD than a cup brush)  so it takes me about an hour to do one side of a 60ft boat.  The underneath is harder work!

 

N

[blackrose]

2 minutes ago, BEngo said:

You dont really need to push, even gently.   You can see you're doing it right  as the thin oxidised grey layer disappears and the 2 pack black shows.  If you are going through to the steel you are pushing far too hard.

 

The saucer wheel gives  the maximum coverage  ( bigger OD than a cup brush)  so it takes me about an hour to do one side of a 60ft boat.  The underneath is harder work!

 

N

 

Ok fair enough. But I'm sure to give a uniform key a sander is easier and quicker, and there's less chance of going through the paint. 

[BEngo]

3 hours ago, blackrose said:

 

Ok fair enough. But I'm sure to give a uniform key a sander is easier and quicker, and there's less chance of going through the paint. 

Dunno.  I have never tried a sander for keying 2 pack.  I wonder though if the paper  would not clog too quickly.

 

N

 

[blackrose]

23 minutes ago, BEngo said:

Dunno.  I have never tried a sander for keying 2 pack.  I wonder though if the paper  would not clog too quickly.

 

N

 

 

I've haven't had a problem with paper clogging because cured epoxy tends to powder rather than melt as it's abraded, but the paper can become dulled by the hardness of the paint which is why you need a coarse grit paper as I mentioned, and of course change the paper as required.

[system 4-50]

On 02/05/2024 at 08:40, BEngo said:

Prep for sides:

 

Pressure wash, angle grinder with saucer type twist knot wire brush to take the greyness  off the surface.

Two pack.

 

Prep for baseplate:

 

Ideal World: Shot blast

Real world: pressure washer  at 200bar or more.  Wire brush when dry.

 

Unless it is shot blasted I would only use bitumen on the bottom.  Work it  well into the pits.

 

With epoxy all over 5 or 6 years between dockings is OK.  With bitumen I think that is too long an interval.  I would want to check every 3 or at most  4 years.

 

While out: 

Check the inside of the weed hatch and the inside of the rudder tube, at the waterline, for pitting.  Make sure you paint them inside.

Check the stern tube and bearing  for play. About every 10 years draw the tail shaft out and see how it is wearing where the gland packing runs.

Renew the gland packing.

Renew any worn out anodes.

Check the lower end of the rudder post and the cup in the skeg for wear.

Paint the tunnel bands.

Clear out any drains ( sink, shower etc.) while you can get at both ends.

 

 Take the fenders off and clean the rubbish out of them.

 

N

and empty the ashtrays.

[cuthound]

On 05/05/2024 at 11:29, blackrose said:

 

I think a wire wheel on an angle grinder is a bit aggressive if you're just trying to give the surface of the existing epoxy a key. You'll end up going through to the steel. Plus it will take you forever to go around the whole boat with an angle grinder.

 

If after pressure washing the existing epoxy looks sound then all it needs is a key with a sander and a coarse grit paper, plus go over any rust patches with the wire wheel. If it's not sound it's all got to come off and that means blasting.

 

If you're still talking about the hull sides below rubbing strakes by all means feather the edges of any patches that have gone back to bare metal but don't bother trying to build up coats to the same level unless you have lots of time or are particularly precious about how the hull sides look. You must refer to the the technical data sheet for any epoxy you're using. Particularly important are the mixing ratios (easier by weight than volume with kitchen scales if the relative weights are given), mixing thoroughly and only then adding the correct thinners if required (10% max or according to TDS), minimum overcoating times and minimum time for service (back in the water).

 

My boat was re-blacked with 2 pack less than 5 years ago. The yard (which if you want to know which one then PM me) roughened up the old blacking with a wire brush in an angle grinder, but obviously didn't rough it up enough because 4 years on the blacking started to blister.

 

I took it to Glascote Basin for an out of the water inspection and they found the new blacking came off in parts when pressure washed.

 

I am now having the boat grit blasted and the 2 pack blacking redone from scratch by Glascote Basin because using a wire brush polished rather than roughened the original blacking.

[ditchcrawler]

12 minutes ago, cuthound said:

 

My boat was re-blacked with 2 pack less than 5 years ago. The yard (which if you want to know which one then PM me) roughened up the old blacking with a wire brush in an angle grinder, but obviously didn't rough it up enough because 4 years on the blacking started to blister.

 

I took it to Glascote Basin for an out of the water inspection and they found the new blacking came off in parts when pressure washed.

 

I am now having the boat grit blasted and the 2 pack blacking redone from scratch by Glascote Basin because using a wire brush polished rather than roughened the original blacking.

Is that where she is now?

[cuthound]

32 minutes ago, ditchcrawler said:

Is that where she is now?

 

Yes, due back next week.

[DShK]

On 06/05/2024 at 19:35, cuthound said:

 

Yes, due back next week.

Now I know what all the racket was about this morning!

[Mrpj]

Hi all,

I’ve only just found this thread.

I work as a marine surveyor, and see an awful lot of narrowboats (and other craft) in all different conditions.

There are a great many theories as to whether it’s worth coating the baseplate, and I always recommend coating the baseplate - if it is possible to do so!

The analogy I use to my clients is this: -

“Imagine immersing an uncoated lump of steel in water for twenty-plus years, and expect to take it out after this length of time - what will it look like?!”

[DShK]

7 hours ago, Mrpj said:

Hi all,

I’ve only just found this thread.

I work as a marine surveyor, and see an awful lot of narrowboats (and other craft) in all different conditions.

There are a great many theories as to whether it’s worth coating the baseplate, and I always recommend coating the baseplate - if it is possible to do so!

The analogy I use to my clients is this: -

“Imagine immersing an uncoated lump of steel in water for twenty-plus years, and expect to take it out after this length of time - what will it look like?!”

 

My theory is that the conclusion of not painting the baseplate comes before the reason. For example, mine isn't done because the yard that built the boat didn't have the facilities at the time to do it. I think that's probably not uncommon.

 

A bit of mental gymnastics later and "it would probably be a waste anyway!"

 

There's also the precedent from working boats where the bottoms were often cut out and replaced.

Edited May 8 by DShK

[Lady M]

Advice to black the baseplate seems to be quite common from surveyors - we have had it from three now.  We had ours done about 20 years ago and most of the bitumen is still there.  There is wear along the edges and some small missing patches from subsequent surveys.  Our boat is relatively shallow drafted.  The most recent survey included the advice again and we think the surveyor had not looked first!