Recently we bought a shipment of white louvers for residential electric heaters from an off-shore supplier. Unfortunately, the paint used on the louvers by the off-shore plant is not up to that standard, so the louvers turn from white to brown where the heat comes out in the electric heater unit. How do we correct the problem? How many choices do we have? What is the easiest and least costly way, relatively speaking?
The parts we produce are cleaned in an iron phosphate washer and sometimes these parts seem to raise scum to the surface of the paint tank. Is it possible that the material that is surfacing is carbon from the steel tubing? What can I do to solve the problem?
I believe the input supplied by G.D. in a previous Painting Clinic may be in error. I do not believe that the nascent protective (chromium) oxide layer on the stainless surface needs continuous regeneration so long as nothing damages the surface—and particularly if it is protected from any electrolyte by a paint.
There are numerous ASTM Specification covering dip and laboratory-type viscosity cups which address both precision and correct method of use. The importance of temperature control and the nature of Newtonian flow cannot be stressed more and is often overlooked to the detriment of flow cups in general.
I am interested in finding out information regarding the size of the market for dip spin finishing equipment. Information regarding suppliers of the coatings and equipment would be helpful.
I would like to know if it is possible to paint Type 304 stainless steel with a high-solids epoxy-type paint (per MIL-C-22750). If not, can you recommend a paint system that would be more suitable for this alloy? What type of primer is recommended for this surface?
How do the powder epoxies compare to high-end wet epoxies? Also, how do the zinc phosphate treatments for powder coating compare to a zinc primer? Although we doubt we can beat the zinc/epoxy system we currently have, is it possible properly pretreated steel with a powder epoxy may outperform a zinc/urethane system? Is washing as good as blasting?
