Interior sandblasting and painting

Excuse the hotch potch of photos, there is no great order on this page but more of a mix of points regarding the sandblasting and painting inside the boat.

Not one compartment of the boat was sandblasted in one go. It is important to get the white steel coated as soon as possible and also important to have it coated before the dew falls on it. Considering the time to sandblast, time to clean up and finally time to paint, that leaves only time for a limited surface to be finished each time.
When we start, there is no time to rest, its a hell ride and you are off only when it is done and all is cleaned up. Mark and I have worked up to 20 hours straight on a sandblasting chore. That was on our previous boat, we were young, crazy and much tougher back then; we now try to plan a little smarter.

Here’s the order of steps we sandblasted the inside of boat:

  • Holding tank and surrounding
  • Water Tank and surrounding (Potable water specfic paint)
  • Front compartment
  • Under deck Main compartment
  • Topsides Main compartment
  • Bilges Main compartment
  • Fuel Tanks and surroundings (Diesel specific paint)
  • Under deck aft compartment
  • Rest of the aft compartment

 

A few days before sandblasting we apply a very thin, high surface tension epoxy around all the frames for it to coat all the areas we will not be able to sandlblast.

We kept the cabin top off to sandblast the interior of the boat

It’ already claustrophobic enough in the suit, having the cabin top off was a nice bonus

Sand everywhere

Its a lot of cleaning before we can paint

 

Two part epoxy paint needs to be well stired

First coat going on white steel

 

Looking clean after a coat of paint

You will notice some grey and some white paint on my photos. It is all the same coating, bar rust 235 but we alternate colors for each coat to facilitate the painting and make sure all surfaces get coated evenly.

A coat of whit following a coat of grey

Epoxy paint is nasty! I don’t think my brain cells could survive the fumes without good protection

Every coat of paint we go through loads of consumable.  When epoxy paint sets, its sets everywhere, including in the brushes and roller. We usually need to change brushes, rollers and gloves every half hour. We also plan multiple trays and mixers.

Rollers, brushes, more rollers…

 

A word about sandblasting media for inside the boat

We have used 4 different types of blasting media inside our boats

We used the “Black Magic” on our first steel boat. I cant say too much about it as we had very limited experience back then and used less then ideal rental equipment. All I can recall is liking it better then the more sand-like media.

We did most of this boats interior with Sorelmix for the simple reason that it was the easily available, we purchased it from our neighboring truck restoration shop. To my non professional experience, the Sorelmix worked just as well as the black magic. All my previous information is using Sorelmix

Our neighbor eventually changed his sand to JetMag 35-70 and within the first time using it inside the boat, we found it way too dusty. While it was a fine blasting media to use outside, on the interior of the boat it made hell that much more hateful.

That’s when we were forced to explore different option which came down to trying the Jetmag in 30-60 grit or the MAxiblast (copper slag). What we were after is a no silica abrasive that would provide the appropriate anchor pattern for our paint and limited dust while sandblasting. Our first observation is that most abrasive sales brochures seem to praise there product as low dust (well then…) . I found it interesting that one blast media is praised for its low density for more blasting material (JetMag) and an other evenly praised for its high density carrying more energy (Maxiblast). We finally decided to give a try to the more expensive but most convenient (home delivery by the pallet with unloader) option; the Maxiblast – copper slag.

Wow!! With non hesitation I will say that the copper slag has been my favorite blasting media for the boats interior. It seriously produces less dust then the other medias we have used. This stuff is so heavy that it falls straight down. It’s high density does make it more aggressive and it bounces off surfaces hard enough to blast a hard access surface (as behind tight frames). For the mil scale we still had left to remove, the maxiblast just at it away. It is also the first blasting media we have successfully reused; this said, we only blasted the reused sand on exterior surfaces as we feared the more broken down grit may be more dusty. The copper slag is more expensive then the jetmag sand so we will do a trial of both one after the other to decide what we will be using for the rest of the exterior.

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