Potential Silicone Issue

[Alan Gardella]

I am refinishing a friends solid cherry coffee table which had some scratches and divots through the factory finish. I scraped the finish off and sanded to the bare wood. I stained it with GF Black Cherry water based stain until the original factory color was restored.

I have done this five times now, because no matter what I use as a top coat either has fish eyes, alligatoring, or is otherwise totally unacceptable. Here is an example of my top coat process and products:

1) One coat of thinned shellac. No issue with finish. This was followed by two coats of GF water based semi-gloss. Issues showed up.
2) Two coats of Danish oil and dried for two weeks, then shellac, GF water based, and issues showed up.
3) Two coats of GF water based only and issues show up.
4) Two coats of GF SOLVENT based finish and issues show up.

I was speaking to a highly respected furniture maker and he stated at some point, someone could have used a silicone polish which has contaminated the wood.

How do I deal with a potential silicone issue and get a good finish.

[glenn bradley]

The shellac should create a barrier coat that would remove any problems with underlying contaminants. Shellac is used for this very purpose in many situations. Did you try your finishing schedule on another piece of material with the surface prepared exactly the same. The only valid test board is one with identical prep. Maybe your barrier coat was too thin? Maybe the problem is on the 'outside', not the 'inside'. Your test piece will tell you that.

[Alan Gardella]

I am desperate and am tired of looking at this. I will prep a piece of cherry I have and see what happens.

I have put a variety of topcoats on walnut, cherry, white and red oak, maple, and other domestic hardwoods and NEVER had this problem.

I initially used the shellac knowing that it would seal the wood prior to the finish topcoat.

The other option is to make a new top from my own lumber, knowing everything from the beginning of prep. I think I have a bit to match the existing profile.

[John TenEyck]

I would strip everything off with KleanStrip Premium stripper. If there is any finish or color still in the pores strip it again, then neutralize it with their Afterwash. Wipe it two or three times with the Afterwash, using new paper towels each time. Some folks say to use a clean paper towel for each swipe! I've never done that, but it's extremely important to remove any silicone still there and not spread it around.

Now start over with new everything, including any finishing products you dipped a rag or brush into and any brushes you need. After the staining is done, I would spray it with a coat of Sealcoat shellac. If you don't have spray equipment then use their rattle can shellac, it is dewaxed, too, but spray it twice because it's a very low cut. Spraying the shellac avoids pulling up any silicone that might still be on the piece and will seal it in. You should be good at that point.

John

[Jim Becker]

'Just as an aside...if you were using a brush, you may have contaminated the finish in the containers if you do, in fact, have a contamination situation.

[Wayne Lomman]

Following on from John' good advice, make sure your first coat after the shellac isn't so wet that it penetrates all the way through the shellac. Build up multiple light coats rather than fewer heavy coats. Cheers

[Gary Muto]

I've had good and bad experiences like this. My lesson learned was that I think I was sanding through the shellac and breaking the seal. Once I used a lighter touch and applied multiple coats, I was able to seal it.

Since then I use a sanding sealer under any water based finish and have not had a problem

[Prashun Patel]

1) To repeat Jim's question, What brush or applicator are you using?
2) What specific products are you using? In all but one case, the common denominator is the "GF Water based". Is it the "High Performance Top coat"?
3) In your 4th trial, you used "GF Solvent Based". Which one? Arm-R-Seal? Also, which brush/applicator did you use for this? Was it the same one as you used in trials 1-3?

[M Toupin]

Alen, What type of shellac are you using? As John said, you want to use Zinsser Sealcoat which is dewaxed. If you're using the regular Zinsser shellac it has wax in it which will cause the symptoms you describe.

Mike

[Bill White]

Years ago when I worked in a piano shop, we used a "fish eye eliminator" additive in the NC lacquer. Is that product still available? I think it was a Sherwin Williams product.
Bill

[Steve Schoene]

Fish eye eliminator is a very last resort. It contains silicone, that allows the new finish to be as slippery as the old, so there are no fish eyes, but the cost is essentially contaminating your gun and shop.

[Bill White]

Any port in the storm.
Bill

[Alan Gardella]

Here is an update on finishing the table top:
I started all over again. Got the stain right with no problem.
I bought new fresh cans of SealCoat, and GF water based top coat. I suspect the ones I have may have gotten old and/or contaminated.
Sprayed two coats of SealCoat, with an Earlex 5500, rubbing out between coats.
Sprayed two coats of GF top coat, rubbing out between coats.
It turned out very nice. I will rub out the finished top and put my usual paste wax on it.

Thanks for all the tips.

[John TenEyck]

Glad it turned out well. Next time, don't sand until after the first topcoat. The idea with the Sealcoat is to seal in any silicone that's still there. Sanding it could easily cut through and expose the silicone and then you are right back where you started.

John