boat painting

[Jacqmar]

we decided to have our 10 year old boat re-painted as the touch -up job we had planned last year didn't take place and the boat was starting to look a bit tatty especially where we had rubbed down, primed but gone no further. had a call from the painter to advise there is more work than originally planned. certainly not huge rust problems visible but there are greyish spots on the cabin sides which they say are corrosion and that the best course ofaction is to gritblast first.as the paint job is costing an arm and a leg we don't want any added expense it at all possible. However I understand the painters dilema as he doesn't want to do a botched job at the risk of his reputation.

As we are planning to sell the boat next year we are a;so in a dilema!!! Anyone any ideas what the grey spots could be? They don't look like rust to us and we thought sanding would be enough to eliminate them, obviously not the case.

[Ex- Member]

we decided to have our 10 year old boat re-painted as the touch -up job we had planned last year didn't take place and the boat was starting to look a bit tatty especially where we had rubbed down, primed but gone no further. had a call from the painter to advise there is more work than originally planned. certainly not huge rust problems visible but there are greyish spots on the cabin sides which they say are corrosion and that the best course ofaction is to gritblast first.as the paint job is costing an arm and a leg we don't want any added expense it at all possible. However I understand the painters dilema as he doesn't want to do a botched job at the risk of his reputation.

As we are planning to sell the boat next year we are a;so in a dilema!!! Anyone any ideas what the grey spots could be? They don't look like rust to us and we thought sanding would be enough to eliminate them, obviously not the case.

 

Possibly Grey primer, it's quite porus and when left unattended it can get little rust spots developing below the surface. If it is primer, inspect it closely, if it's gots specks and you can see tiny rust spots, this is what the painter might be seeing also. And yes it would need removing completely, just rubbing down and painting over the top will have the same thing happening in a very short time through the new paint.

 

Boats painted with Grey primer suffer this a lot, it's strange that some boat builders use it when supplying a cusomer with just a primed shell, as it's not designed to be weathered, but to be painted over asap. The Red oxide type primer weathers much better.

[Jacqmar]

Thanks for reply, looks like the job is going to be bigger than we thought! We are going to talk with the painter and inspect the boat tomorrow so will keep in mind what you have advised.

[Phil Speight]

Possibly Grey primer, it's quite porus and when left unattended it can get little rust spots developing below the surface. If it is primer, inspect it closely, if it's gots specks and you can see tiny rust spots, this is what the painter might be seeing also. And yes it would need removing completely, just rubbing down and painting over the top will have the same thing happening in a very short time through the new paint.

 

Boats painted with Grey primer suffer this a lot, it's strange that some boat builders use it when supplying a cusomer with just a primed shell, as it's not designed to be weathered, but to be painted over asap. The Red oxide type primer weathers much better.

Quite right - although many redoxides are not weather proof either . There really isn`t a rule of thumb here - what matters is what is in the primer- it`s colour ( these days anyway ) is barely relevant . You`re bang on about the rubbish unprotected primer boat builders tend to use! The "why" question is easy. Price is usually the governing factor!

I shouldn`t want to have the boat blasted if I was selling it next year - there are other ( less expensive ) ways of taking paint off and removing rust . Only loose millscale would justify blasting given your future plans. The painter is quite right to be cautious though and he is no doubt concerned that he should be allowed to do the best possible job. I`d be interested to know who is doing the job - people with blasting facilities are always worth knowing !

Cheers

Phil

[Jacqmar]

Went to see the painter today, the grey spots when scratched reveal rust underneath. His options are gritblast which he advises will be expensive and time consuming or removing the exsisting paint with a grinder?? Is that right ? I must admit couldn't take it all in! And then "padding out " and using two pack ???

He did say he could not guarantee that the spots would not come back, but it was a cheaper option and as the boat is 10 years old and never been painted before it may be that it will last longer.

He does not do the gritblasting himself, would have to be done elsewhere.

Think we will go with the cheaper option and cross our fingers!

Any suggestions on what to do with the new paintwork i.e. wax protection?

[BEngo]

Went to see the painter today, the grey spots when scratched reveal rust underneath. His options are gritblast which he advises will be expensive and time consuming or removing the exsisting paint with a grinder?? Is that right ? I must admit couldn't take it all in! And then "padding out " and using two pack ???

He did say he could not guarantee that the spots would not come back, but it was a cheaper option and as the boat is 10 years old and never been painted before it may be that it will last longer.

He does not do the gritblasting himself, would have to be done elsewhere.

Think we will go with the cheaper option and cross our fingers!

Any suggestions on what to do with the new paintwork i.e. wax protection?

 

I'd go with grind it out, rust treat it ( Fertan/vactan/...) prime and paint. IWe used to do that on warship flight decks and, if done properly would last about 5 years. Then it all got blasted.

 

After painting leave it well alonne until the paint has properly hardened- 2 weeks before any boating and 6 months to be fully hard. Then wax it with a good wax. Some bloke who posts on here sells one and it sems to work well on the boat next to mine. I usually use Turtle Wax or Autoglym (cos the old Queen Mum used to do the Daimlers with it. Every Sunday before the lunch-time G&T I heard.) There are other good waxes available.

 

Since you plan to sell next year you won't need to worry beyond that, but a good polish is sometimes necessary after a few years if the paint starts to fade or chalk/bloom with age and weather. G3 and/or G10 with a proper polisher are good for this.

 

N

[Jacqmar]

I'd go with grind it out, rust treat it ( Fertan/vactan/...) prime and paint. IWe used to do that on warship flight decks and, if done properly would last about 5 years. Then it all got blasted.

 

After painting leave it well alonne until the paint has properly hardened- 2 weeks before any boating and 6 months to be fully hard. Then wax it with a good wax. Some bloke who posts on here sells one and it sems to work well on the boat next to mine. I usually use Turtle Wax or Autoglym (cos the old Queen Mum used to do the Daimlers with it. Every Sunday before the lunch-time G&T I heard.) There are other good waxes available.

 

Since you plan to sell next year you won't need to worry beyond that, but a good polish is sometimes necessary after a few years if the paint starts to fade or chalk/bloom with age and weather. G3 and/or G10 with a proper polisher are good for this.

 

N

 

Thanks for advice, think we will leave the grit blasting and take option 2!!

Is it crucial to leave for 2 weeks before boating? we will have to move the boat from the boatyard at least. had plans for couple of weeks afloat in july. autoglym has been recommended so will probably use this unless the bloke is reading this and can advise of his product!!