Ask the Expert Question-and-Answer Archive

by Ron Joseph

February, 2007

Application of Inorganic Zinc Primer

Q: The finish obtained by spraying inorganic zinc silicate primer (by conventional spray gun) is not appropriate with a lot of overlaps leading to the appearance of patches.

Kindly suggest correct spray application method for Inorganic Zinc silicate primer.

A: It is extremely difficult to apply inorganic zinc under any circumstances. There is so much zinc in a very small volume of ethyl silicate that it is not easy to get a wet finish. Moreover, unlike other paints, this primer does not flow out after it has been applied. Ethyl silicate inorganic zinc primers are used for corrosion protection rather than for appearance and customers need to understand that painters might not be able to achieve a high quality appearance.

Conventional spray guns might not be able to get as good a finish quality as airless or air-assisted airless guns which, by their very nature, apply a wetter coating. If appearance is an issue for you, consider experimenting with one of these two spray guns. BUT please bear in mind that both guns, especially airless guns operate at high pressures. Painters MUST, I repeat MUST be properly trained to use them on account of the potential dangers that exist with high pressure equipment. All of the instructions that come with the user's manual must be followed.

Finally, painting technique play a role in appearance; therefore, your painters must use commonly good application practices. Unfortunately, this is too broad a topic to be covered in an email.

Hope this helps.

Regards,

Ron Joseph