Troubleshooting Waterborne Finish Beading on "Green" Particleboard

A finisher tackles compatibility problems with architect specs on a "green" commercial job. April 18, 2010

Question
We are doing a project using green products such as NU Green particle board. The designer specified General Finish Enduro finish as a clear coat over the particle board. We are having some trouble with the finish - it seems to be beading up. We used both a sealer and top coat. Has anyone had any experience with this product and can offer any solutions? We don't have much experience using the water based finishes.

Forum Responses
(Finishing Forum)
From contributor D:
I had it happen once. I would suggest you trade in the Enduro for their High Performance Poly if they require you to stay in the same product line. I am told it is a lower viscosity version of the same product. The theory is that it has a lower surface tension and will alleviate the problem. If they allow you the freedom to move away from the poly I would then go to the pre cat urethane and sealer. I have had much better luck with this system.



From the original questioner:
I will look into those products. The product is for a restaurant in NYC. We are required to go with a green product and still have it be durable. I'm thinking that poly is not low voc, etc. Plus we would not be dust free enough for the dry time of poly and the application would be difficult to apply on the volume of material we are doing.


From contributor E:
Target finishes will meet LEED requirements and will probably perform as good or better.


From contributor E:
Sorry I just read your post again. What kind of volume are you talking about 30 sheets? You are mistaking the waterborne poly as a slow drying product but in fact this morning I did two full coats on maple panels and had it installed in the clients house dry in two hours. The finishes need warmth and airflow. I am thinking that the Nu green particle board due to the phenolic resin is causing surface tension with the product. It is also a so called non-porous surface which may have a higher concentration of the resin that Uniboard uses which may be incompatible and cause the finish to bead as you say. I just read on the Uniboard website that the glue in the Nu Green is water resistant which may be doing it. Waterborne will not wet the surface like solvent. I have a feeling that the designer is not clear as to what they will get simply by specifying two green products. It looks like they are incompatible. Did they have a sample to show you?

What about a waterbased shellac sealer? This might be the answer to using a green product and sealing the particle board at the same time. An alcohol shellac sealer will work perfectly but again you are too high on your VOC content. The poly is not what is contributing to the VOC content of a waterborne finish. That is the resin. It is other components in the mix so you have to read the MSDS/PI sheets carefully. What is your VOC limit?