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Shop primer is an primer thin primer for clean steel that keeps the steel from rusting during construction. Most shop primers contain low amounts of zinc. They are "weldable" or designed so that they will not contaminate welding, so it is not necessary to grind them off before welding. The down side is they only last about 6 months so they are not great for long term building projects.  Another argument for not using shop primer is that you depend on it doing it's job well because sandblasting the hull is expensive and you don't want to do it twice.

Inorganic zinc primer is zinc metal powder mixed into an inorganic silicate paint binder.   Zinc primer is 85 to 90% Zinc by dry wait is recommended. The zinc is electrical conductivity and allows the primer to provide sacrificial protection to any areas of exposed underlying steel.  Organic Zinc primers consist of zinc suspended in epoxy and while these are good the Inorganic zinc primer that uses silicate paint has faired better in NASA conducted test.


Thermal Ceramic Spray http://xiom-corp.com  $15,000 for the application equipment and it requires 30 cfm of compressed air.

MetalTec 2300SS BallPark $160/gal 2mil coating
Steve Stefansic 800 321 2978

Sherwin Williams Commercial  664-5694  --Eric
Zinc Clad II Ethyl Silicate Inorganic Zinc-Rich Coating Binder Part E 4GL-KT
Part Number:  B69V00003
$135.49 Binder, Zinc Dust $225.05  -- 5 gal Kit  = $180/gallon

Cleaner to work on steel thereafter, welding easy with weld compatible primer Interplate 937

http://ceram-kote.com/ ceram-kote 54 CeRam-Kote 54*. ($195/gallon covers 128 sq. ft.)

Weld Through Primer
Sigmaweld MC  -- Sigma is now PPG
2 parts, 24 hour pot life, overcoat in 6 months

Coal Tar Epoxy or Epoxy Tar

Wasser Coatings
Robin Posgay, Houston Texas:  (281) 467-1717
Order Entry: 800 627-2968   -- Prices are good till Jan 2009
MC-Zinc 100  thinned by 15% to get 1 1/2 to 2 mil. Best to spray.  Normal coverage 200 sg. ft / gal
Might last 5 years.  Blast, prime and then spot blast, weld, spot blast again and spray to reprime.
Prior to final coat, pressure wash, add final  MC-Zinc 100 and then MC-Tar - Red / Black and top coat.
MC-Zinc 100  -- 85.68/gal, 256.04 /3gal
MC-Tar - Red / Black  --  Black 51.44 /gal  249.37 /5gal   Red: 251.45 /5gal
MC Thinner   -- $97.00 /5gal  -- Use with Zinc and Tar 

Square foot estimate:
1 - coat of MC-Zinc 100 at 256.04/3gal.  /3 =  $85.35/gal  /Coverage rate of 200 sq ft/gal = .43 / sq ft
2 - coats of MC-Tar at $250/5gal /5=  $50/gal /Coverage rate of 200 sq ft/gal = .25/sq ft x2 coats = .50/sq ft

Plus thinner, tax, shipping, and application consumables that is over 1$ / sq ft. Then we still need topcoat and anti-fowling paint. ...This is one of the reasons why we nearly waited until I could afford aluminum, but our steel plate came to $6.75 / sq ft delivered including tax.  The zinc and epoxy tar coats on each side for the steel will add another $2 / sq ft.  Even still, aluminum came to about $16.15 / sq ft so there is a lot of up front savings to cover the cost of blasting, and coatings.

To save money an immersion system is not required on the inside.
Use either MC-Miozinc 100, best to spray or MC-Prepbond 2.8  which is easy to brush.
MC-Miozinc 100    -- $65.04/gal,    $194.13 3gal   
MC-Prepbond 2.8  -- $50.62 /gal    $245.28  /5gal

Zinga: http://carwellspecialtycoatings.com/Zinga

Ameron is now PPG
Amercoat 385 - 2nd coat need to go on within 30 days

Dimetcote 9 --Not for submerged use
Dimetcote 302H zinc primer with Amercoat 370, 385 top coat
Dimetcote 302H is 2 part, 4 hour pot life, 1 year shelf life
Distributer: www.corrotherm.com

Carboline Co Lake Charles, LA
Carbozinc 11, Carbozinc 11HS
Distributer: www.somay.com/distrib/carbo

International Paint, Inc Houston, TX
Interzinc 22

PPG Aremcoat
I've found over the years that Ameron's 214, which is a relatively inexpensive as bottom paints go, works well for me. I use Ameron 302 and top that with several coats of 235 epoxy as base coats, then top that off with a couple of coats of the 214.


Ceramic beads are from Hy-Tech, They are for insulation. enough to treat 5 gallons cost me about $75 with shipping
and they recommend 2 coats. Cant say how well it works yet but its supposed to help with condensation also.


Water Tanks

Concrete Wash - 2 parts portland cement, 1 part fire clay.  Mix to paint like consistency.  Apply two coats over blasted metal. Submerse in water to dry.