What would you do?

[Old Son]

I have 2 pack epoxy blacking on my hull. There are a couple of areas that have been damaged by welding up some lockers. During a conversation with a guy at the yard I asked if it was worth re-coating the complete hull again with 2 pack. He said it wouldn't stick and it would peel off and I would need to get back to bare metal so there is no point.

 

He said he would touch up the damaged areas with 2 pack then coat up the hull with bitumen. That way it would have a great base and next time it needed to be blacked up it would be much cheaper that blasting back to bare metal to re-coat.

 

It makes sense to coat the hull again whilst it is ashore. Would I be wise to coat with a couple of coats of bitumen?

[Tony Brooks]

I have 2 pack epoxy blacking on my hull. There are a couple of areas that have been damaged by welding up some lockers. During a conversation with a guy at the yard I asked if it was worth re-coating the complete hull again with 2 pack. He said it wouldn't stick and it would peel off and I would need to get back to bare metal so there is no point.

 

He said he would touch up the damaged areas with 2 pack then coat up the hull with bitumen. That way it would have a great base and next time it needed to be blacked up it would be much cheaper that blasting back to bare metal to re-coat.

 

It makes sense to coat the hull again whilst it is ashore. Would I be wise to coat with a couple of coats of bitumen?

 

 

Personally I would clean up the damaged area with an angle grinder and then do a local repair with the same 2 pack. Until I am convinced differently I suspect the bitumen's adhesion to the epoxy may not be very good, but time would tell.

[David]

HI

absolutely agree with tony, we had 2 pack epoxy on two boats for many years. After the initial grit blast, done properly back to bright silver look to the metal, 2 coats of 2 pack with plenty of time to cure the only treatment then needed is where bashes and bangs have gone through to the metal is grind the area and patch with 2 pack, we docked about every 4 years. You should expect many years of life from the initial 2 packing before griting again.

david

[blackrose]

I have 2 pack epoxy blacking on my hull. There are a couple of areas that have been damaged by welding up some lockers. During a conversation with a guy at the yard I asked if it was worth re-coating the complete hull again with 2 pack. He said it wouldn't stick and it would peel off and I would need to get back to bare metal so there is no point.

 

He said he would touch up the damaged areas with 2 pack then coat up the hull with bitumen. That way it would have a great base and next time it needed to be blacked up it would be much cheaper that blasting back to bare metal to re-coat.

 

It makes sense to coat the hull again whilst it is ashore. Would I be wise to coat with a couple of coats of bitumen?

 

I don't think your man knows what he's talking about. New twin pack will stick to old twin pack if the same stuff is used.

 

Any areas of rust should be taken back to metal with the appropriate grade of wet & dry before applying new 2 pack, but previous applications of 2 pack which are still sound don't need to be taken back to metal - they just need to be given a key - again with the correct abrasive.

 

Putting patches of bitumen over twin pack is foolish because that would have to come off before applying a complete new coat of twin pack, so you'd have to remember where the patches were. Unless of course you decide you want to use bitumen for the whole boat from now on - which is foolish too!

 

If you've got the best stuff on your hull why would you want to compromise it with inferior crap?

Edited June 14, 2010 by blackrose

[Robbo]

I have 2 pack epoxy blacking on my hull. There are a couple of areas that have been damaged by welding up some lockers. During a conversation with a guy at the yard I asked if it was worth re-coating the complete hull again with 2 pack. He said it wouldn't stick and it would peel off and I would need to get back to bare metal so there is no point.

 

He said he would touch up the damaged areas with 2 pack then coat up the hull with bitumen. That way it would have a great base and next time it needed to be blacked up it would be much cheaper that blasting back to bare metal to re-coat.

 

Don't touch it with bitumen, if you have 2 pack, keep too 2 pack (2 pack goes over 2 pack), it's the the best. If you use bitumen now you'll have to go back to metal to do 2 pack again.

[Old Son]

Thanks for all your responses. I wasn't planning to touch up the rusty areas with bitumen. I was going to touch up with two pack.

I thought I would recoat the whole lot with another coat of two pack but was told it would peel off so I would be wasting my time. It was sugested I coat the whole lot with bitument. That could take the wear and then I could recoat every 3 years and reblack with bitumen knowing there was ample protection underneath with the two pack.

 

Based on the responses I have received I will touch up with two pack and ask Hemple if I would have problems adding another coat of 2 pack over my existing 2 pack finish.

 

 

Spelling errors

Edited June 14, 2010 by Old Son

[Denis R]

I've got 2-pack etch prime on bare steel with 2-pack epoxy over the top. Last September the damaged bits were re-treated with etch prime and then the whole hull re-blacked with 2-pack epoxy. The local boatyard told me that was the way to go and never to put bitumen over epoxy. The guy told me that they can tell when a hull has had epoxy for its first blacking and bitumen thereafter, as the jet washer peels the bitumen off like sheets of wallpaper, leaving the now exposed original 2-pack intact...

[c c]

When Badsey had a new hull we put on two coats of two-pack. Three years on and we put on two more coats of two-pack. We had it out of the water recently and it was still perfect after over six years. We were told by the manufacturers that the two pack will eat into the last coat to get a good fix so long as you use the same brand. I certainly would not put bitumen over it. The two pack may cost a bit more but it will go twice as long beteen blackings. Incidentally, we put all coats on in very cold weather when many will tell you it will not go off, but in fact, it just takes longer to cure.