FAQs & Troubleshooting
Common Questions
Can I apply my finish over an existing coating?
The practical answer is……Possibly. Rule of thumb: You can generally apply the same type of coating over itself e.g., precat over precat, conversion varnish over conversion varnish, etc. Waterborne coatings can generally be applied over solvent-borne coatings, but not the other way around as they may lift/wrinkle the coating.
Important Note: Overall film build is a concern with these types of finishes. If too much coating is applied, the finish can shatter or crack no matter which coating you are applying over the previous finish. Always consult your Gemini Sales or Technical representative before re-finishing, so that you may avoid any potential issues.
How can I remove a blush?
If the blush is in a nitrocellulose lacquer, it can be removed easily by mixing 50% thinner with 50% retarder and applying a mist coat to the surface of the blush. (The thinner will open the film and the retarder will allow the coating to stay open long enough for the blush dissipate.) You may also spray a light film of ABLUSH100 aerosol retarder on the blush to re-open the film and remove the blush. If the blush is in a pre or post-catalyzed coating that is cured, the blush will most likely not come out. However, if the coating is not completely cured it may be possible.
How can I prevent a blush?
If you are working in hot and humid conditions, it is always best to add retarder to the coating before you apply. This will slow the dry of the coating enough to prevent a moisture blush. Refer to the Product Data Sheet for the product you are using for the recommended type and amount of retarder to add.
Why am I seeing bubbles in the film?
Bubbles are usually caused by the coating drying too quickly and trapping air before it can exit the film. This can be either caused by high temperatures or too much air movement over the coating film while it is drying, causing it to skin over. This can be avoided by adding the correct amount and type of retarder to the coating before application. Refer to the Product Data Sheet for the product you are using for the recommended type and amount of retarder to add.
What are fisheyes and what causes them?
Fisheyes (AKA craters) usually appear as circular depressions in the film that can either be large or small. Sometimes they have raised edges like a crater and sometimes are less pronounced. Fisheyes can be caused by contamination of the surface, contamination of the product, or dirty air lines. Common causes are water or oil in the air supply, cleaners, and lubricants, etc. Check out our troubleshooting section below and read our 10 step process of elimination to help you discover the source of the contamination.
Do precatalyzed lacquers have a limited shelf life?
Precats have a shelf life of approximately 6-12 months from the date of manufacture depending on the formulation. They are made with the addition of a small amount of acid catalyst which helps to make the film more durable and chemical resistant. Using a precat past its shelf life is not recommended.
Why can’t I get lacquer to flow?
There are 2 likely reasons.
It is likely too thick:
- This could be by design (the particular product is designed to be thinned before use).
- The lacquer/coating may be cold. Like the oil in your car, coatings increase in viscosity (get thick) when they are cold. If this happens you will need to add the correct thinner for that product until the coating becomes thin enough to flow out nice and flat.
- The container may have been left open. This will allow the solvents in the container to evaporate which will cause the coating to be thick.
The air temperature is very hot:
- Another reason may be that the air temperature is too hot or there is excessive air movement in the immediate area. This may cause the lacquer/coating to dry too quickly, and it may set up before it can flow out completely flat. Adding the correct retarder for your coating will slow down the drying allowing the coating to flow out correctly.
Detailed Troubleshooting Guide
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