Replies

1. 
   PeteBradley | Apr 21, 2006 07:35pm | #1

   Did you maybe sand with stearated paper?

   Pete

1. 
   TXJon | Apr 21, 2006 08:06pm | #2

   Used 3M Imperial wet/dry.  But that's what I used all over, and I only had the problem on one area.

2. 
   jblogan | May 03, 2006 12:17am | #8

   Would stearated sand paper cause fisheye?
   Thanks Jerry

1. 
   PeteBradley | May 03, 2006 01:26am | #9

   I wouldn't expect so.   I was curious though whether there was anything more to the original story about sanding that might shed light on the problem.

     My only complaints about shellac are due to its sometimes weird behavior caused by surface tension, like piling up on sharp edges.  I don't think that's a primary factor here.

   Pete

1. 
   jblogan | May 03, 2006 01:39am | #10

   Thanks Pete. I just posted " shellac over poly" with my latest problem.
   Jerry

2. 
   SteveSchoene | Apr 22, 2006 04:50am | #3

   I don't understand the wet sanding of the Minwax stain on the poplar with water.  The Minwax created only a very thin film at best.  Wet sanding with water would quickly cut through the stain, leaving wet poplar and a bare spot. Wet sanding only makes sense when you have a full film of a hard finish like varnish.  Minwax is a stain with a very dilute oil/varnish mix as a binder.  It won't tolerate wet sanding. 

   Did you wait for the poplar to fully dry before applying shellac?  Which Zinsser shellac did you use, exactly.  They don't sell a liquid shellac called blonde, only Clear, which is bleached, Amber which is orange shellac, and SealCoat, which is blonde but not labeled by Zinsser as such, but which is more noteworthy as being dewaxed shellac. 

   Finger prints contain oil, and in this case likely contained something else, such as silicone from car wax or ???.  The silicone could prevent shellac from adhering, and when sanded further could spread the contaminent.  How did you notice the fingerprints?  If they were apparent in the minwax, it is likely they prevented the minwax from adhering to the poplar. 

   I still don't feel I understand the full picture so I am still puzzled at what is going wrong.  Perhaps you could post pictures of the problem. 

1. 
   TXJon | Apr 22, 2006 03:54pm | #4

   Thanks for your help.

   I applied the shellac (Zinser Clear) to the stained, fully cured poplar.  The first coat was thinned with dna to be pretty thin, but I didn't measure, so I can't tell you the exact cut.

   Subsequent  coats had a couple runs, nibs, etc., so I wetsanded the fully cured (24-36 hrs dry time, hard, no odor) shellac.  That is when I first noticed the problem.  The shellac would coat the finger prints when wet, but would crater up around them when drying.

   I sanded these out and reapplied shellac a couple times, and now the whole side of the frame won't take shellac.  It goes on wet, then piles up on the inside edge of the piece.  It is laying flat and level, so I don't imagine gravity is the problem.

   I plan to strip all the shellac from that frame, and start over.  I would like to understand what went wrong so I don't do it again, though.

   I could try to post pics, but even if I got them right, you would only see a frame with three shiny sides, and one dull.

1. 
   Gretchen | Apr 22, 2006 05:01pm | #5

   Why would you wet sand shellac when all you have to do is reamalgate with alcohol. Water is not shellac's best friend.Gretchen

2. 
   SteveSchoene | Apr 22, 2006 05:34pm | #6

   The cratering effect strongly suggests there was something on the hands that made the fingerprints such as silicone.  So the first step is to try to remove that material with heavy scrubbing with mineral spirits.  Sanding just spreads it around, as you have discovered.  Then you should be able to recoat with shellac.  You may not need to strip everying since you can fill in any sand throughs with the Minwax, being sure to wipe it off of any sealed surfaces.  After the minwax cures, you ought to be able to recoat with shellac.  It will patch itself into the old shellac fairly well. 

3. 
   forestgirl | Apr 22, 2006 05:38pm | #7

   I have no idea what's screwed this up for you, but I can tell you what I'd try if it were 1a.m. and I had no one to ask for advice:  I'd wipe down with DNA to remove as much shellac as possible, let dry, then I'd sand, then I'd wipe down a couple of times with Naptha to get whatever gremlin was living there gone, hopefully.  Let it dry well, and then re-apply shellac.  If I were feeling exceptionally paranoid, I might make my first coat de-waxed (Zinsser SealCoat) and the second coat the regular.

   If you don't get any more info here, you might as well try that since it's sounds like that frame is pretty much history.  None of the wet-sanding. 

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-) 

   Edited 4/22/2006 10:45 am by forestgirl

3. 
   mike4244 | May 03, 2006 12:44pm | #11

   Did you make the moldings for the frames ,or buy them? If you made the profiles, did you use something on the machine tables that could prevent the finish from adhering.Shellac over minwax stain works well. Finger prints in the stain finish probably had nothing to do with the shellac not adhering, unless you had a substance on your hands like grease or some other foreign substance. The glue from them crappy stickers they put on bought moldings  might also be the culprit.

   mike