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Kevin Arceneaux
06-12-2005, 10:43 AM
We finished some walnut with water based poly and the grain raised. What other woods have a problem with raised grain?

Jamie Buxton
06-12-2005, 10:54 AM
All that I've tried -- and that's quite a few. Approximately 50% of what's in the can is water, so it shouldn't be a surprise that the grain raises.

Me, I just figure that the first coat is a sanding sealer, and I plan on resanding after it. It doesn't take much -- just skim the surface with 400 grit to knock off the nibs.

Richard McComas
06-12-2005, 1:16 PM
We finished some walnut with water based poly and the grain raised. What other woods have a problem with raised grain?I have recently been using Fuhr water-based pre-cat lacquer. I shoot a coat of Zinsser seal coat ( #2 cut shellac). The seal coat eliminates the grain raising and provides a good barrier coat against any contamination that might be on the wood which water-based finish seem to be less forgiving of.

You could also make your own seal coat from flakes to impart a particular color to the wood.

Jim Becker
06-12-2005, 1:38 PM
Grain raising is normal for any water bourne finish. Just raise it first before spraying...and knock off the fuzzies before your first coat. Once you spray that first coat, let it dry and then knock any remaining fuzzies down with 320 wet and dry. Proceed from there. Alternatively, as Rich points out, you can also use a barrier coat of de-waxed shellac; use super blond flakes to avoid major color changes.

But you know...some folks don't bother with most of that. They just spray the first coat of water bourne, let it dry and knock off the fuzzies with 320 wet and dry before proceeding with the rest of the coats. I did this with my kitchen cabinets and it worked just fine.

Mike Cutler
06-12-2005, 4:11 PM
I imagine all of them raise to some extent. Not much you can do it about it but plan for it.
I normally sand to about 180 and then do a flood coat, I've been using General Finishes, Seal a Cell, that is applied with the grey 3M pad, and I really try to work it in. I wipe off the excess with a wetted edge and let it sit for 24 hours. I then hit the top with a 320 grit sanding sponge, and apply a lighter coat. I keep repeating the lighter coats as necessary and use 400 grit in between.
I read somewhere that sanding bare wood to 220 and higher was a waste of time. The author's premise was that subsequent sanding with finer grits was "flattening" the fibers and not removing them, thus allowing them to raise anyway after the first finish coat is applied. I'm not sure that I agree with this 100% . I think it really depends on the species of wood, but for Mahogany and Jatoba it seems to hold true. Mopane can definitely be sanded to 220 prior to finish though with no grain raising.
Grain also raises with oil finishes, but to a lesser extent than water. I don't use water based finishes, and I still have to deal with raised grain.
My .02 fwiw.