Painting over old Bitumen on hull

[Ex-Member]

On 6/16/2017 at 15:53, Robbo said:

 

Use these if you want/need to remove with out sand blasting; http://tercoo-rotating-blaster.co.uk/

Hi   have you used this and if so to what effect?   I have just had my boat blacked, although I am embarrassed to say so as the result is so bad (no names no pack drill) but needless to say I intend to redo it and fancy having a go myself. I have found a local DIY dry dock and, having used their domestic paints before, a company called Promain who sell just about every kind of paint domestic & industrial you can think of. (worth a look, some of their stuff is for oil rig struts etc) I want to get the surface down to bare metal and then paint it with a Zinc paint they sell which acts as a kind of Galvanic Isolator (Debdale wharf do a similar thing , look it up on Youtube  but it is £4 to £4.5k.  They then have a selection of paints under the name 'Jotun' which they have recommended and say it can last up to 15 yrs.   Anyway first things first which is the best way to get the old layers of bitumen off??   

On 6/16/2017 at 15:53, Robbo said:

 

Use these if you want/need to remove with out sand blasting; http://tercoo-rotating-blaster.co.uk/

 

[Robbo]

1 hour ago, Numpty said:

Hi   have you used this and if so to what effect?   I have just had my boat blacked, although I am embarrassed to say so as the result is so bad (no names no pack drill) but needless to say I intend to redo it and fancy having a go myself. I have found a local DIY dry dock and, having used their domestic paints before, a company called Promain who sell just about every kind of paint domestic & industrial you can think of. (worth a look, some of their stuff is for oil rig struts etc) I want to get the surface down to bare metal and then paint it with a Zinc paint they sell which acts as a kind of Galvanic Isolator (Debdale wharf do a similar thing , look it up on Youtube  but it is £4 to £4.5k.  They then have a selection of paints under the name 'Jotun' which they have recommended and say it can last up to 15 yrs.   Anyway first things first which is the best way to get the old layers of bitumen off??   

 

I would recommend.  However to make sure you could get one and try it on your blacked boat that’s above water to see how it works for you (especially if you1r boat has deep pits).  When you do it in a dry dock I would hire the 8 disc tool as the 1-3 discs on a drill would takes ages. 

[WotEver]

28 minutes ago, Robbo said:

When you do it in a dry dock I would hire the 8 disc tool as the 1-3 discs on a drill would takes ages. 

And heed the instructions to NOT push hard against the steel otherwise you’ll ping the teeth off and you’ll be charged. 

Jotun is often mentioned on here as a pretty good blacking but I’ll leave it to someone who knows the product to give more info. 

[Dr Bob]

Jotun are one of the top paint companies when it comes to performance. I'd put Jotun and International Paints at the top of the pile.

[abnormalsheep]

On 16/06/2017 at 16:52, Machpoint005 said:

But it isn't compulsory. I have no intention of reopening one of the perennial controversies on this forum, but since it's an old boat I suggest it is unlikely that it has a blacked baseplate. 

It has a whole new base plate, so it is currently not blacked, but not because it is old

On 20/09/2017 at 12:15, abnormalsheep said:

Hehe, epoxy is now well behind me.

I think I will keep using the wire wheel (gently) until satisfied with bitumen removal, then use one of the recommended primers before the layers of fresh bitumen.

The new steel definitely has millscale... a kind of weird shininess. I think I will use a really soft grade flapping disc to remove it? 

I have been removing the paint right the way up to the gunnel, and was thinking to bitumen the whole of the sides, unless it is the wiser consensus to use a different paint above the waterline?

Re: winter.... as I have procrastinated so long, the season is fast approaching. There are still plates to be welded at the front of the boat, so realistically wouldnt be able to paint until october/november... which is probably too late to do a decent job? 

 

On 20/09/2017 at 13:24, abnormalsheep said:

Someone just wandered over and recommended aluminium phosphate... is this the same compound as the primocon and vinyguard?

Just recapping some questions. Been reading a lot about using a zinc based paint. Another guy on the yard said with so many options, to just do what I want... ha.

Sorry if it is tedious to ask such questions..! Thanks for all the advices!