Blacking advice

[beatnik]

We're planning to do our own blacking (first time). We bought the sailaway two years ago (Liverpool Boats), and so I'm not sure what they originally blacked it with.

But, we wanted to use 2pack epoxy anyway (Hempadur 45143) so that it will last longer.

 

Whatever they've used is pretty thin now as we can see lots of rust patches, but do you think it would still need grit blasting or should pressure washing plus scrapers and electric wire brushes do the job to get it off?

 

We can't grit blast it so I'm just worried about buying 2-pack epoxy and then realising that we can't manually get back to the bare steel and needing to instead use bitumen.

 

 

Anyone done similar with a Liverpool Boats hull?

[RobinJ]

We're planning to do our own blacking (first time). We bought the sailaway two years ago (Liverpool Boats), and so I'm not sure what they originally blacked it with.

But, we wanted to use 2pack epoxy anyway (Hempadur 45143) so that it will last longer.

 

Whatever they've used is pretty thin now as we can see lots of rust patches, but do you think it would still need grit blasting or should pressure washing plus scrapers and electric wire brushes do the job to get it off?

 

We can't grit blast it so I'm just worried about buying 2-pack epoxy and then realising that we can't manually get back to the bare steel and needing to instead use bitumen.

 

Anyone done similar with a Liverpool Boats hull?

Apart from the odd patch with wire brush or scraper (usually above the water), never had a problem with a good jet washer on bitumen!

[Mac49]

We're planning to do our own blacking (first time). We bought the sailaway two years ago (Liverpool Boats), and so I'm not sure what they originally blacked it with.

But, we wanted to use 2pack epoxy anyway (Hempadur 45143) so that it will last longer.

 

Whatever they've used is pretty thin now as we can see lots of rust patches, but do you think it would still need grit blasting or should pressure washing plus scrapers and electric wire brushes do the job to get it off?

 

We can't grit blast it so I'm just worried about buying 2-pack epoxy and then realising that we can't manually get back to the bare steel and needing to instead use bitumen.

 

 

Anyone done similar with a Liverpool Boats hull?

 

When my parents' boat was blacked, the boatyard did gritblast before applying the epoxy (sprayed I think). It lasted very well, infact i'm in a similar position to you, having a Liverpool boat with the original blacking (international) which is looking a bit scruffy now after less than a year in the water so I think i'll go down the same route in the spring. The long life of the epoxy probably had a lot to do with the fact it was applyed to the well prepared grit blasted surface, certainly all traces of the bitumen had to be removed.

Rick

[WotEver]

Apart from the odd patch with wire brush or scraper (usually above the water), never had a problem with a good jet washer on bitumen!

 

But a jet wash won't remove Bitumen. It'll take off any loose stuff and it will clean it, but it won't take you back to bare steel.

 

My understanding from the yards that have blacked our boat is that you can't use two-pack over bitumen. Hence we've always just stuck with bitumen (it's cheaper anyway).

 

T

[denboy]

But a jet wash won't remove Bitumen. It'll take off any loose stuff and it will clean it, but it won't take you back to bare steel.

 

My understanding from the yards that have blacked our boat is that you can't use two-pack over bitumen. Hence we've always just stuck with bitumen (it's cheaper anyway).

 

T

 

correct 2 pack will just fall off if you leave the slightest trace of bitcho

[TandC]

Sorry to take off at a tangent, our boat was two-packed - as far as renewing, is it simply a case of re-applying over the top or does it need grit-blasting?

 

Any ideas how long two-pack lasts on average (we liveaboard and do not do a great deal of cruising at all, as an idea of use) - the pre-purchase survey noted that "the rust -proofing is unusual (i guess they were referring to the 2-pack as opposed to bitumen) but is obviously effective and shows no sign of corrosion" - that was a year ago, so was wondering what and when we need to consider redoing it.

 

Thanks

[Drayke]

We're planning to do our own blacking (first time). We bought the sailaway two years ago (Liverpool Boats), and so I'm not sure what they originally blacked it with.

But, we wanted to use 2pack epoxy anyway (Hempadur 45143) so that it will last longer.

 

Whatever they've used is pretty thin now as we can see lots of rust patches, but do you think it would still need grit blasting or should pressure washing plus scrapers and electric wire brushes do the job to get it off?

 

We can't grit blast it so I'm just worried about buying 2-pack epoxy and then realising that we can't manually get back to the bare steel and needing to instead use bitumen.

 

 

Anyone done similar with a Liverpool Boats hull?

Hi I had the same problem with my liverpool wide beam. It seems to be the mill scale they leave on the steel that makes the blacking come off. If you can affored to have it shot blasted then this will take the blacking and mill scale off and give a good key for the two pack. I had this done and put on five coates then allowed it to harden for ten days. have only had this done a year ago so don't know how long it lasts.

Regards Drayke.

[Orca]

I think a 2-pack coating has a minimum of 5 years in it, providing it has been applied properly. I'm currently re-blacking mine and whilst epoxy most probably is the best, it certainly ain't the cheapest and the preparation required for a hull already in bitumen is preclusive (imho). My boat is 20 years old and was reblacked every year from new - '88 up to '07 without fail (using basic bitumen from a DIY store)! There is only very negligible rust pits around the waterline I found today; though as I don't want to haul it out the water again for at least another 3 years, it's still going to get 4 good coats of the good stuff over primer!

 

2 coats International Primocon around the waterline

1 Full coat Rylard's Rytex

3 coats of Sigma Vikote 63

[beatnik]

Thanks everyone. I think now we're going to jet wash it and then angle grind it back to the bare steel.

With 2-pack lasting at least 5 years, it will be much cheaper than us hauling it out of the water every two years (London cranage prices!)

 

Now, I'm just concerned about how to go about doing it on a hardstanding without cover. This wet weather isn't going to make it easy to fully cure.

 

What do people do about the rain? Put tarpaulins around the boat?

[WotEver]

Thanks everyone. I think now we're going to jet wash it and then angle grind it back to the bare steel.

 

That will take you days, and days, and days... I'd STRONGLY suggest you invest in one of these.

 

I have nothing to do with this company, I just think their product is one of the greatest tools I've come across in a long while.

 

Good luck,

Tony

[Smelly]

What do people do about the rain? Put tarpaulins around the boat?

 

I've certainly slung tarps over a boat in times past... Fastened to a fence all round with a couple of joists lashed into the front, tent pole style.

[soldthehouse]

That will take you days, and days, and days... I'd STRONGLY suggest you invest in one of these.

 

I have nothing to do with this company, I just think their product is one of the greatest tools I've come across in a long while.

 

Good luck,

Tony

Have you actually used one of these , whats it like !

[WotEver]

Have you actually used one of these , whats it like !

 

yes I have - it's great. It leaves the steel with a dull grey 'grit blasted' look

[Patterdale]

A lot of the blacking MAY scrape off with one of those big scrapers you get at DIY shops. Sometimes it comes off, sometimes it doesn't. And get plenty of spare blades.

[ChrisPy]

That will take you days, and days, and days... I'd STRONGLY suggest you invest in one of these.

 

I have nothing to do with this company, I just think their product is one of the greatest tools I've come across in a long while.

 

Good luck,

Tony

which model did you buy?

did you fit it in a drill?

how much can you clean in an hour?

 

sorry about the inquisition ..........

[WotEver]

which model did you buy?

did you fit it in a drill?

how much can you clean in an hour?

 

sorry about the inquisition ..........

 

The single

Yes

About 2 sqm - but that's all I had to do and why I only bought the single

 

T

[denboy]

if you are going down the 2 pack route i would suggest you have it grit blasted the merest trace of any bitcho will and i repeat will cause the 2 pack to fail

[Smelly]

yes I have - it's great. It leaves the steel with a dull grey 'grit blasted' look

 

Did you two pack over it? How long ago?

 

If it's as good as it says on the tin the epoxy manufacturers may see an increase in their sales... The needle gun approach it seems to use appears to be a really good approach.

 

OP... I'd be concerned at trying to grind it back as it's quite a hot process and the bitcho will melt and smear around, you'd struggle to see where it's left behind. Even the slightest skim will prevent the epoxy binding back to the steel.

 

We had to get some welding done under the waterline a couple of weeks ago (while in dock) and the welder said he'd refuse to do it if there was any of the old bitcho left at all he'd be reluctant as getting it off with a grinder is very difficult.

[nb Innisfree]

A lot of the blacking MAY scrape off with one of those big scrapers you get at DIY shops. Sometimes it comes off, sometimes it doesn't. And get plenty of spare blades.

 

Wouldn't it be great if we could reproduce the conditions over all the hull of patches of blacking that won't come off?

[Gary Peacock]

2 pack epoxy is nasty the HSE implications of using it in a professional role make it more or less impossible.

 

The stuff will poison you really easily and I speak from experience having been done in by the stuff twice, after that I got wise and wont go near it again.

 

The stuff smells like normal blacking but without you have a positive pressure air fed mask and suit it will get you either through inhalation or absorption through exposed skin.

[Orca]

Wouldn't it be great if we could reproduce the conditions over all the hull of patches of blacking that won't come off?

 

Yes absolutely, though in my experience so far it's called hauling your boat out EVERY year and re-applying it - but this of course is preclusive to most boaters (me included)! I was lucky in that the previous owner DID do it every year and the hull now has a build of of old bitumen as thick as your thumbnail in places. Of course, some areas the pressure washer blows it back to steel, but the majority is very obstinate and doesn't want to come off, so regardless of age (some of it may well be 20 years old) I ain't upsetting it! I do feel that bitcho (by that very name) has been made a nemesis pariah in recent years as alledgedly better coatings come on the market. Buying big scrapers from DIY stores and taking off what quite possibly doesn't need to come off is throwing money, time and effort to the wind IMHO...

Edited August 6, 2009 by Orca

[WotEver]

Did you two pack over it? How long ago?

 

Hi Smelly,

 

I used it on a rusty counter, so I was removing paint and painting over the prepared surface. That's been highly effective, albeit only recently. However, having used the tool I do believe it would be effective at removing blacking even though I haven't actually used it for that purpose myself.

 

Cheers,

Tony

 

Buying big scrapers from DIY stores and taking off what quite possibly doesn't need to come off is throwing money, time and effort to the wind IMHO...

 

Totally agree - some of our blacking is, I'm sure, 20 years old underneath the new coating.

[badgerburger]

We're planning to do our own blacking (first time). We bought the sailaway two years ago (Liverpool Boats), and so I'm not sure what they originally blacked it with.

But, we wanted to use 2pack epoxy anyway (Hempadur 45143) so that it will last longer.

 

Whatever they've used is pretty thin now as we can see lots of rust patches, but do you think it would still need grit blasting or should pressure washing plus scrapers and electric wire brushes do the job to get it off?

 

We can't grit blast it so I'm just worried about buying 2-pack epoxy and then realising that we can't manually get back to the bare steel and needing to instead use bitumen.

 

 

Anyone done similar with a Liverpool Boats hull?

 

We did this at our last blacking (LB widebeam), due to various problems (including the on-site pressure washer failing). It took 2 of us 3 days to clear it back to bare metal, using angle-grinders/wire brush attachments (& we wore out a few of these).

 

 

It's possible, but a big job... & I totally agree with G.P. about how toxic epoxy is, having used it elsewhere.

 

B.B.

[beatnik]

Hi, another question.

 

We have a bow thruster tube fitted, but not yet the bow thrusters (and they are getting more and more unlikely).

 

How do we go about blackening it? We couldn't possibly reach the whole way to scrape it back. We could use a long roller brush, but the scraping is an issue. Would it be best to jsut power wash through it and use bitumen inisde the tube (even though we'll have epoxy on the rest of the hull)?

 

 

Sooo regret having the tube fitted (and doubting our boating skills, thinking we'd need thrusters eventually).

[WotEver]

Would it be best to jsut power wash through it and use bitumen inisde the tube (even though we'll have epoxy on the rest of the hull)?

 

Yep.

 

I still doubt you'll have epoxy everywhere else, because when you start trying to remove all the blacking and realise how difficult it is I think you'll give up. However, even if you don't give up and do have epoxy everywhere else, then yes, simply wash and black the tube.

 

Of course, another alternative would be to weld a couple of plates over the tube ends.

 

T