sandblasting question...

[crosser]

im having my roof sandblasted next month as quite rusty on the surface...  do i still need to put rust converter on the roof before painting the red oxide primer?  thanks

[mrsmelly]

What you do need to do is tape over absolutely every opening on your boat. Vent widow door air intakes etc etc etc etc etc. I had a boat gritblasted a few years ago and oh my oh my 

[David Mack]

9 minutes ago, crosser said:

im having my roof sandblasted next month as quite rusty on the surface...  do i still need to put rust converter on the roof before painting the red oxide primer?  thanks

Only if the blaster leaves rust on your roof!

Get a coat of primer on as soon as possible, ideally before the steel gingers.

[dmr]

Rust converter is not a good primer, it is intended to stick to rust not to bare steel.

[ditchcrawler]

As David said get it painted the same day as its blasted and like Mrs Melly the grit will get everywhere so good sealing is essential, under the vents  and chimney, all doors and windows, consider wrapping the boat in polyethene sheeting taped to the boat. 

[crosser]

thanks for the tips .....   they said they will block off all entry points with ply and tape...   boat needs a good clean anyway so a little grit will be ok...  fingers crossed it wont be to much...  as for rust treatment i gather thats not needed after its been blasted...  so just straight on with the red oxide

[BEngo]

1 hour ago, crosser said:

im having my roof sandblasted next month as quite rusty on the surface...  do i still need to put rust converter on the roof before painting the red oxide primer?  thanks

No.  Get a good primer, preferably non porous, on within 4 hours of the blasting being started.

 

The will not be a little grit.  There will be loads of it.  Mixed with paint dust, rust and any filler that was used.  Tis Orrible.  Been there, have scrapped T-shirt!

 

I  also hope your blaster knows how thin roofs are.  Blasting too hard can cause all sorts of wrinkling of the roof.

 

 

N

[crosser]

cheers, its a boatyard thats doing it so hopefully know how thin roofs are...  theres no paint on the roof so one less thing to get in the boat..  lucky the wife works as a narrowboat cleaner..lol

[ditchcrawler]

1 minute ago, crosser said:

cheers, its a boatyard thats doing it so hopefully know how thin roofs are...  theres no paint on the roof so one less thing to get in the boat..  lucky the wife works as a narrowboat cleaner..lol

Don't get it in in the first place, If you do it will get everywhere

[BWM]

Whatever the boatyard are doing, be sure to wrap the engine/gearbox to protect it and ancillaries (particularly the alternator). Same with any inverter/chargers. 

  An epoxy primer may be worth considering but any decent zinc oxide primer should do.

[Tracy D'arth]

I would 2 pack epoxy it straight away, you can buy it in a range of colours. Its the best long term solution.

[Neil2]

31 minutes ago, Tracy D'arth said:

I would 2 pack epoxy it straight away, you can buy it in a range of colours. Its the best long term solution.

 

Have to agree - if you are going to all the trouble of stripping back to bare metal why not make the most of it. 

 

[Bee]

9 minutes ago, Neil2 said:

 

Have to agree - if you are going to all the trouble of stripping back to bare metal why not make the most of it. 

 

I kind of think that primer is just stuff that you should overcoat within a day or two but last year I primed the back deck of Bee after sanding, scraping and generally taking it back to something like mostly bare steel with Hammerite water based primer, funny looking pink stuff. just slapped a coat on then it rained for 3 days and I had to leave it for nearly 12 months because of covid. Thought it would be awful but it was not too bad. I now use it quite happily for any metal priming.

[dmr]

As you will be masking up the boat to prevent damage from the grit blasting then why not spray a good epoxy primer on straight away (after suitable dusting and cleaning).

Something like Jotamastic 90 will be really tough and can be overcoated in anything else of your choosing. Its really a hull paint so not easy to get a great finish with a brush but would be fine if you can spray it.