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Orange peel effect in epoxy coatings
We are ten seniors building Wood Ducks at our local Senior workshop. The project has been great and we are now in the later stages of our builds. There has been no difficulty in wetting out the fiberglass cloth. But, some of our subsequent coats develop an orange peel effect. This seems to appear only on one side and covers the entire area i.e. tops or bottoms. Some of the boats have a clear flat almost perfect finish and then the other side gets the orange peel effect. We apply the cloth wetting coats with a spreader and following coats with a West Systems foam roller and a natural bristle brush. We tried going back with a spreader to see if the surface would flat out only to have it come back with the orange peel. Is there a recommended wipe down prior to coatings? Is acetone so volatile that even in the same room it will contaminate the surface? We tried a wipe down with a damp cloth and use no solvents or acetone except for cleaning brushes and tools. After searching previous, posts I find few ideas. One builder couple who thought they were doing every thing right had resigned themselves to lots of sanding and a lifetime of aversion to using epoxies! Thanks for any help Keith.
3 replies:
RE: Orange peel effect in epoxy coatings
Try wiping down your hulls using virgin alcohol. Not rubbing alcohol (cheaper but contains oils, etc) or recycled alcohol (probably will have contaminants). Use clean cloths, refolding often, especially if there is evidence of a lot of dust/stuff on the cloths. And put on gloves before you start to wipe down.
The one side good - one side fishy might have been caused by two different people trying to clean a hull; one of them using something that had oil or some such in/on it.
Before sanding a fisheyed epoxy covering, try to wash and rinse throughly to keep any possible contaminants from spreading.
Good luck to all of you!
RE: Orange peel effect in epoxy coatings
It seems odd that some areas came out smooth when others did not; but to touch back on what Fishbuster said - it is normal to get an orange peel effect when epoxying over fiberglass - it's not really orange peel (as you would think of with paint), but rather the "shape" of the weave showing through - a little bit of quality time spent sanding and you should be in good shape.
There is an article in building tips that talks about this
http://www.clcboats.com/shoptips/epoxy_and_fiberglass/fiberglass_weave_epoxy.html
RE: Orange peel effect in epoxy coatings
» Submitted by Fishbuster - Sat, 3/28/09 » 8:39 AM
Epoxy doesn't self level, you will need to do the sanding anyway and fill any valleys that will show up during the sanding. Temperature and where the epoxy is as far as curing time and how long you play around with it applying it can all effect the final finish but that is not the final finish anyway, just precurser to your primer/paint and/or varnish, which is really the final finish.
Don't worry, the sanding is not nearly as bad as people think. The biggest mistake in sanding is not changing the paper often enough. Buys lots to have it on hand and don't be shy about using lots of it.
http://shearwaterkayak.blogspot.com/