PaintSquare.com
Follow us on Twitter Follow us on LinkedIn Like us on Facebook Follow us on Instagram Visit the TPC Store
Search the site

 

Advertisement

PaintSquare


Problem Solving Forum

| More

August 18 - August 22, 2014

How do you measure wet film thickness on shop-applied organic zinc-rich primers to accurately predict dry film thickness? Our shop applies a great deal of OZ primer, and we have found that WFT readings with a standard gauge are not accurate predictors.

More items for Quality Control


Selected Answers

From Larry Muzia of Exceletech LLC on August 22, 2014:
 The wet gage measurement is not exactly accurate  because the metallic zinc particles do not allow the two ends of the gage to make direct contact with the substrate. They are a solid, and if zinc is under the edge, it will prove to be inaccurate. The is the case with both organic or inorganic zinc filled coatings. I agree that an agitated pot or very low speed agitator in the bucket if spraying airless is a must. Remember to keep the speed low to avoid inducing a vortex sucking moist air into the product if the humidity is high. As for accurately measuring the wet film, the use of a wet film gage will give you an approximate reading, although it will not be 100 % accurate. Experience is never out of style, and, typically, these materials dry within hours, allowing a confirmation using a dft gage.

From Steve Brunner of WPC Technologies on August 19, 2014:
I find it odd that a wet film gauge does not yield accurate predictions. Given that, I recommend consistency and a practice board. On the former, thinning the same to a consistent viscosity will keep the solid content nearly identical from batch to batch. Then use a practice (pattern) board for the applicator to determine gun pattern, adjust the application equipment and helps out the applicator with the arm speed. I have seen a lot of applicators who use practice/pattern boards and always end up being spot on with the DFT. The last issue is use of an agitated pot. It has been my experience that zinc-rich coatings will settle in rapidly, thus the need to keep agitated. If not agitated, the coating will have an inconsistent solids content.  On this last thought, this could be the problem and the easiest fix.

Please sign in to submit your answer this question    

Tagged categories: Coating / Film thickness; Dry Film Thickness (DFT); Wet film thickness


Current PSF Question | Submit a PSF Question | Full PSF Archive

Advertisements
 
KTA-Tator, Inc. - Corporate Office
 
KTA-Tator Training Course Opportunities
 
• IACET Authorized Continuing Education Unit (CEU) Provider
• Live Basic Coatings Inspection Courses
• Customized/Private Courses
• Online/self-paced curriculums
Contact: Tiffany Kelly at 412-788-1300 x217
 

 
DeFelsko Corporation
 
PosiTector SST Soluble Salt Tester
 
Measures the concentration of soluble salts on metal surfaces. Use with all Bresle patch types including the reusable, adhesive-free PosiPatch.
 

 
Fischer Technology Inc.
 
NEW Protective Coating Inspection Website
 
Click Here!
 

 
HoldTight Solutions Inc.
 
NO FLASH RUST - NO CONTAMINANTS
 
Our HoldTight®102 salt remover & flash rust
preventer prevents flash
rust by removing surface contaminants. Contact us
for your nearest distributor.
(800) 319.8802 sales@holdtight.com
 

 
SEMicro Division, M.E. Taylor Engineering, Inc.
 
Coatings Adhesion Testers
 
The PATTI® accurately measures the bond strength between coating & substrate. Outfitted properly, the surface can be rough, porous, or curved & >10K psi strong!
 

 
Aggreko
 
Dehumidification, Power and Temperature Control Rentals
 
Aggreko offers rental solutions for your painting/coating project. Dehumidifiers, cooling, heating, power and 24/7 service, nationwide.
844-433-9802
 

 
Advanced Recycling Systems
 
ARS C-Class Recyclers
 
World leading abrasive blast recycling systems in a compact size. Quality, performance, savings… www.arsrecycling.com 330.536.8210
 

 
Safway Services
 
Your Access Advantage. QUIKDECK®
 
Provides safe, factory-floor-like working conditions. Can be engineered to fit almost any shape, structure or size. Modular platform easily assembled from just a few basic components. Excellent containment. Applications include vessels, offshore rigs and bridges.
 

 
Tarps manufacturing, Inc.
 
QUALITY MADE IN AMERICA —Available near you!
 
CLICK to get a behind-the-scenes look at how Tarps Manufacturing makes the highest-quality tarps right here in the USA — available nationwide.
 

 
Novatek Corporation
 
Novatek Corporation, Dustless Coatings Removal
 
Strip, clean and profile all dust free! Comply with new lead standards. Contact today: (866) 563-7800
 

 
 
 

Technology Publishing Co., 1501 Reedsdale Street, Suite 2008, Pittsburgh, PA 15233

TEL 1-412-431-8300  • FAX  1-412-431-5428  •  EMAIL webmaster@paintsquare.com


The Technology Publishing Network

Durability + Design PaintSquare the Journal of Protective Coatings & Linings Paint BidTracker

 
EXPLORE:      JPCL   |   PaintSquare News   |   Interact   |   Buying Guides   |   Webinars   |   Resources   |   Classifieds
REGISTER AND SUBSCRIBE:      Free PaintSquare Registration   |   Subscribe to JPCL   |   Subscribe to PaintSquare News
MORE:      About PaintSquare.com   |   Privacy policy   |   Terms & conditions   |   Site Map   |   Search   |   Contact Us