Grit blasting and epoxy coating keel - good idea?

[maej]

My boat's having osmosis treatment at the moment and the yard have said there are some signs of corrosion on the keel and they have offerred to grit blast, fill, fair and apply 3 coats of epoxy to it for £575 + VAT if I say yes first thing in the morning while she's still in the shed.

Is it a wise investment? A fair price?

She's a Sadler 34 but she has a non standard shaul draft long fin keel. The keel surface is quite uniformly bobbly but I haven't noticed any significant corrosion coming through the antifoul and the surveyor didn't mention it. To my inexperienced eyes the condition of my keel looks about the same as any other nearly 30 year old boat I have seen out the water.

Any comments?

 

[Rigger Mortice]

i've just had a quote for a similar job, though it didn't include filling and fairing. £200 all in.

 

[maej]

Photos

Does this look like it needs attention or is it normal and nothing to worry about?

 

[maej]

i've just had a quote for a similar job, though it didn't include filling and fairing. £200 all in.

Thanks, that a lot less. how big is your keel? I imagine the cost must bear a strong relation to surface area of the keel.

 

[Rigger Mortice]

Mine looks very similar to yours. Size about 6 or 7 feet long. 18" high.
There is swinging keel inside mine which drops down; about 5 feet long. 18" wide.

In answer to your other question. It looks as if your keel will benefit from some attention sometime, but whether now or next winter is another matter. It's certainly not in desperate need of nearly £700 spending on it.

 

[fireball]

Not worth it for the blast but the epoxy as well would get back up closer. Personally I wouldn't bother yet - they're trying to get you on extras that probably don't need doing.
If you come out each year anyway then you can do a blast and epoxy anywhen

 

[Pasarell]

I'm pretty much with Fireball here. Sounds very expensive but filling and fairing could take quite a lot of labour. If you race it might make a difference. If you cruise you won't notice any benefit from the fairing. More important is that they get the cast iron completely salt free and dry before coating. That means blasting, pressure washing at least once then blasting again. A proper job would push the cost up. 3 coats of epoxy are probably not enough for long term protection. Depending on what they use I should think 5 or more are likely to be needed to give adequate protection over the edges of pits, nibs etc.

 

[nickbailhache]

Grit blasting

My keel looks fine after 5 years with treatment of 5 coats of epoxy after grit blasting. She is a Moody 31. Have had a little job done on keel this winter and would suggest that price is not over the top. However could wait till next year!

 

[vyv_cox]

I have the same boat but maybe not the same keel. I had mine grit blasted and epoxy coated many years ago, it lasted ten years but then rust got beneath it. I had it re-done in Greece but some rusty spots after three years need further attention. The main purpose behind the treatment of mine was to apply Coppercoat but if you are not going down that route and are happy to carry on with conventional A/F I wouldn't do any more to it. Use an angle grinder or abrasive discs to cut back the rust, not a wire brush which drives the rust into the surface. Then paint with any decent primer and antifoul.

 

[oldbilbo]

I've been exploring the removal of layered antifoul paint, prior to expoxy coatings and Coppercoat, on a 27' long keeler.

Just in is a quote for abrasive blasting, asking £1200 + VAT.

I'm perhaps in the wrong business.....

 

[Elessar]

I've been exploring the removal of layered antifoul paint, prior to expoxy coatings and Coppercoat, on a 27' long keeler.

Just in is a quote for abrasive blasting, asking £1200 + VAT.

I'm perhaps in the wrong business.....

£1200 Is that 27 ft beam ???

Our abrasive blasting prices start at £324 for a 27 fter.

 

[Elessar]

Not worth it for the blast but the epoxy as well would get back up closer. Personally I wouldn't bother yet - they're trying to get you on extras that probably don't need doing.
If you come out each year anyway then you can do a blast and epoxy anywhen

agree. If it aint broke.....

 

[oldbilbo]

Just in is a quote for abrasive blasting, asking £1200 + VAT.

Yes. 'Blastaway' is probably a specialist.... However, but, I could buy a whole working sailboat for that sum, or get two PBO project-type boats with plenty of change for the Beaulieu Boat Jumble ( where you can expect to see PBO journos fanning out with wads of fivers, haggling the life out of anyone with an old anchor or some tired sails for sale.

Oops! Have I just 'leaked' the subject of a future PBO article?


Thinks - I wonder if the MD of above ltd co. thought I was perhaps a Beemer driver....

 

[Seajet]

To correct my earlier faulty memory, It was a different company who upset my chums; were supposed to just remove antifoul but blasted off the epoxy hull treatment as well...said " Sorry we'll replace with Gelshield " and duly applied Gelshield; without the hardener !!!


I'd be wary of standard epoxy coating on a keel, as any chip or crack will let water in then trap it against the steel / iron - this needs to be done thoughtfully by a knowledgable outfit using the right treatment.

I know of an Anderson 22 which is having the steel keel blasted & treated, not sure if it's epoxy going on ( I'll try to find out ) but the firm specialise in marine coatings; snag is this is near Aberdeen...

 

[Spyro]

The price sounds ok for the work involved but I could think of better things to spend £700 on.

 

[KellysEye]

Blasting and epoxy would fix it. If they havent specified it make sure the first coat is zinc rich epoxy, that's what is used on steel boats.

 

[Elessar]

To correct my earlier faulty memory, It was a company called ARC Antifoul Removal Company who upset my chums; were supposed to just remove antifoul but blasted off the epoxy hull treatment as well...said " Sorry we'll replace with Gelshield " and duly applied Gelshield; without the hardener !!!


I'd be wary of standard epoxy coating on a keel, as any chip or crack will let water in then trap it against the steel / iron - this needs to be done thoughtfully by a knowledgable outfit using the right treatment.

I know of an Anderson 22 which is having the steel keel blasted & treated, not sure if it's epoxy going on ( I'll try to find out ) but the firm specialise in marine coatings; snag is this is near Aberdeen...

That was us - not quite the story but it was one that didn't go as well as it should have at first. We came to an amicable conclusion and the culprit no longer works for us...........
I doubt you can find a company that has never made a mistake, it's how you fix them that counts. That and not making the same mistake again !

I think quality epoxy is a good coating for keels generally. What else would you suggest?

 

[Seajet]

Well as long as you have taken steps, that's all anyone can ask.

Personally I think epoxy is too hard, forming a 'shell' which is just asking for trapped water as soon as the layer is chipped.

Maybe a particularly good primer is the answer, certainly it's preparation.

My boat has a steel lift keel and cast iron ballast bulb; as the lift part is moving in a tight slot which may well have stones around in the mud, I avoid epoxy and use 'conventional' paint.

After trying every steel treatment going, I have found Dulux Metalshield ( 1 part, but requiring its' own 1 part primer ) gives by far the best results I have ever had.

The boat is ashore on high trestles every winter, allowing keel inspection & maintenance.

Possibly epoxy may better suit a boat with a fixed keel which does not come into contact with the seabed etc, but it's naive to think a keel can survive long without some sort of impact, be it from flotsam, shore handling, whatever.

 

[pyrojames]

Waste of time and money IMNSHO. With a large mass of iron, the wastage is insignificant. As soon as you scrap, bump or nick the surface you will get corrosion. I had mine done 2 years ago, and I shouldn't have bothered, it is almost back to where it was. Touch up each year as required.

 

[oldbilbo]

£1200 Is that 27 ft beam ???

Our abrasive blasting prices start at £324 for a 27 fter.

I'd be more than keen to follow up, but the boat is near Bath, not Shotley, so the travelling on-cost would be prohibitive. And it's where it is to save me money....!