08-26-2012 11:58 AM
Solved! Go to Solution.
08-26-2012 04:36 PM - edited 08-26-2012 04:38 PM
… let me take a moment to welcome you to the WOOD Magazine Forums, particularly to the Finishing & Refinishing Forum. I hope you will visit often. You will find a number of accomplished woodworkers and finishers here who stand ready to assist you with your finishing and refinishing questions.
Walnut is a semi-ring porous (or semi-diffuse porous, depending on your point of view) hardwood. As such, it is not the most ideal wood to use for a countertop; however, it is certainly not the worst choice you can make and I am sure it will be beautiful. The key, then, is to make sure that the finish you apply offers you excellent hardness and adequate moisture (water-vapor) resistance. The finish should also be easy to repair should the need arise. To accomplish these objectives I offer the following:
Begin by applying a couple of coats of de-waxed shellac. The best option would be shellac that you mix fresh from flakes in a two-pound cut. My choice would be super blonde. Because shellac is dissolved in alcohol it dries very quickly; typically in less than 30-minutes. Given that you want to brush it on quickly with little or no overlap at the wet edge and a minimum of back-brushing. This isn’t your finish; the shellac will serve only as a moisture barrier, so don’t agonize on the look. Just get it brushed on quickly. It would be a good plan to apply the shellac even to the underside of the countertop if you are able. Make sure you thoroughly cover the exposed end grain. When the last coat is dry lightly sand with 220P and a backer block. Sand just enough to smooth the surface. You don’t want to cut through the shellac.
After sanding apply a topcoat of Waterlox Original varnish in the sheen of your choice. Waterlox is a phenolic resin varnish made from tung oil. Phenolic resin is the hardest of the resins commonly used to make varnish and tung oil, when used to make varnish, is produces a somewhat more moisture resistant varnish. Waterlox Original is available in gloss and satin. The two can be mixed to produce the semi-gloss sheen. You can either brush the varnish on or, better still to prevent brush marks, you can wipe it on. Make sure to apply varnish to the end-grain where the sink will drop in.
When you are finished please post some photos…
08-26-2012 05:46 PM
I made some kitchen coutertops out of cherry and finished it with 3 coats of Waterlox. After two years they still look great. There are a few scratches and dings where someone dropped a can or pot but otherwise the Waterlox is holding up well.
This is a photo from today after 2+ years.
08-28-2012 07:03 PM
09-20-2013 07:57 PM
yes, presuming the 'poly' finish is sound. I would lightly but evenly scuff sand the older varnish. DThat might not be absolutely necessary but it won't hurt as long as you don't cut through to bare wood. I'd use 320 grit.
09-21-2013 04:01 AM
… to the WOOD Magazine Forums, particularly to the Finishing & Refinishing Forum. I hope you will visit often. You will find a number of accomplished woodworkers and finishers here who stand ready to assist you with your finishing and refinishing questions.
Now, let’s be certain of the context of your question since you have added it to a thread having to do with finishing a wooden countertop. Yes, Waterlox can be applied over varnish made with urethane resin (Polyoneverythane) as long as the surface is thoroughly cleaned and uniformly roughed first. However, depending on your application, whether or not you should apply Waterlox over poly is quite another question. If you are also finishing (or refinishing) a countertop or even a heavily used kitchen or dining room table I would suggest that Waterlox over poly is not a good plan.
Waterlox is a tung oil base phenolic resin varnish. Because of the properties of the phenolic resin, Waterlox is much harder than Polyoneverythane. (Think of the soft ice cream cone with the hard chocolate shell.) As a result you will be applying a hard, less flexible film over a relatively much softer and more flexible film. In applications not subject to heavy use the combination will probably not create any significant problems. But, in applications where abrasion and impact are more likely I would strongly encourage you to remove the poly first.
Sanding would not be the best way to remove the existing finish. Sanding removes crisp detail and is certain to cup or dish out flat surfaces in areas where more sanding is necessary or the wood is somewhat softer (wood is not a uniformly manufactured product. It is subject to fluctuation in grain structure and density across it surface due to different growing conditions from year to year while the tree was still living.) A good chemical stripper is more effective and, as an added benefit, it will not damage patina.
If you proceed with Waterlox over the existing poly finish, in addition to scuff sanding I suggest you first wash the surface with a mild detergent and water. Towel dry, allow the surface to completely air dry, then wipe-down with shop towels and paint thinner/mineral spirits. Orient the shop towel to a clean surface with each wipe. Then scuff sand. This will not only rough the Polyoneverythane to improve adhesion; but, it will remove dirt, household grime and other gunk that might otherwise create adhesion problems…
11-11-2013 03:58 AM
Hi, I also have walnut butcher block countertops which are going in my kitchen island with a sink. My contractor is recommending Interior Hardwood Penofin to finish them. With some research I found that it uses a Brazilian Rosewood Oil base and can be applied using a wet-sanding method for a gloss finish. My contractor has done me well up to this point and I don't want to push him into using a product he is not comfortable with. Any comments on how the Penofin stands up to Waterlox would be greatly appreciated. Thanks, Chris
11-11-2013 06:22 AM
Are you going to use the top to do meat and or veggie cuts?
If yes, I would strongly recommend that you not do that.
If strictly for looks, you may do it with Waterlox.