Replies

1. 
   Jed_C. | Feb 14, 2000 09:16pm | #1

   *
   Is your display case located so that it receives a lot of direct sunlight? Is the space heated by a forced hot air furnace?

1. 
   Kenneth_Reeves | Feb 15, 2000 05:59am | #2

   *No, the display case receives no direct sunlight. The light it receives comes from a window that faces north. The room is heated by forced air but the case is not in the air stream. There is a humidifier in the room which is on at night some of the time.

1. 
   Jed_C. | Feb 15, 2000 08:36pm | #3

   *Diagnosing a finish sight-unseen is difficult, to say the least, but this one intrigues me. There's nothing wrong with your finishing steps, as you describe them: a sealer coat of tung oil, 3 coats of shellac topped off with a coat of wax should give you enough protection to last for years. Assuming that you first let the tung oil dry thoroughly, the unknown variable here is how much shellac you actually applied to the surface. What cut of shellac did you use, and how did you apply it (brush, rag or spray)?Your mention of the humidifier could be a significant clue here. It's possible that the wax has clouded slightly from the introduction of the concentrated moisture in the air, which would leave the surface looking dull and lifeless.To return to your original question, yes, the walnut absorbed the tung oil, as it should. But shellac dries as a film finish that sits on the surface of the wood, and the wax offers little more than the nice smell and the pleasant feel you get from the rubbed surface.I'll check in after you reply to my questions about the shellac and suggest steps you can take to solve this problem.

1. 
   Kenneth_Reeves | Feb 16, 2000 06:36am | #4

   *My guide for this finishing project was an article by Jeff Jewitt in FWW #112. On page 62 he states that he likes "linseed and tung oil best". After he has applied "the oil" he says,"After several minutes, begin applying shellac". Perhaps he is referring to linseed and not tung oil. Looking back, I see that the picture on page 60 shows linseed oil. Anyway, I rubbed the surface briskly with a dry cloth and probably began applying shellac within 20 minutes. The inside of the case still looks good, but maybe it just hasn't had enough air yet. I used a 2 lbs. cut. I brushed on the first coat and did not like the overlapped areas so I sprayed the next two coats with an HVLP system. I scuff sanded with 400 grit and waited 24 hours between coats. I waited three days before I applied the wax. I just tried buffing the surface in hopes of clouded wax but no changes occurred. Thanks for your help, Jed.

1. 
   Jed_C. | Feb 18, 2000 08:01am | #5

   *When I first read that you'd applied your first coat of shellac over a freshly wiped coat of oil, I suspected that might be the cause of your problem--that the wet oil was plasticizing the shellac. But I talked to a finish chemist who assured me that was not the case. He said wet oil would do that to lacquer but not to shellac. My other doubts--that you simply hadn't applied enough shellac--were put to rest when you told me you'd used a brush for the first coat and an HVLP gun for the 2 other coats.I'm left thinking all you probably need to do is lay on another thin coat of wax (preferably one containing carnauba wax as an ingredient in the blend) using 0000 steel wool to apply it, and buff the surface out. If that doesn't give you the results you want, you can easily remove the wax by wiping it off with a rag soaked in paint thinner, apply a couple more coats of shellac and buff that out with some rubbing compound.

2. 
   Jed_C. | Feb 18, 2000 08:01am | #6

   *When I first read that you'd applied your first coat of shellac over a freshly wiped coat of oil, I suspected that might be the cause of your problem--that the wet oil was plasticizing the shellac. But I talked to a finish chemist who assured me that was not the case. He said wet oil would do that to lacquer but not to shellac. My other doubts--that you simply hadn't applied enough shellac--were put to rest when you told me you'd used a brush for the first coat and an HVLP gun for the 2 other coats.I'm left thinking all you probably need to do is lay on another thin coat of wax (preferably one containing carnauba wax as an ingredient in the blend) using 0000 steel wool to apply it, and buff the surface out. If that doesn't give you the results you want, you can easily remove the wax by wiping it off with a rag soaked in paint thinner, apply a couple more coats of shellac and buff that out with some rubbing compound.