Problem with shellac

[Jim Tobias]

I have used this routine with success several times before, but this time(after 3 attempts) I am still getting craters in the shellac topcoat.
Here is finish schedule:
- Danish Oil
- Spray can Zinnser shellac as barrier coat
- HSF grain filler-water based (Target Coatings)
- Spray can Zinnser shellac as final coat

I have tried 3 times on this one piece and get the same results every time(consistent , at least).
Help!!

Jim206501

[Faust M. Ruggiero]

I think you have too much build. Why are you using a grain filler after the oil? Shellac wants to be applied in extremely fine coats. A French Polished piece may have 40 coats and still be microscopically thin.
faust

[Jim Tobias]

Thanks for the reply. I used the filler because there was some rough spots(pitting) on the spalted wood and I was trying to fill them some so it would not take so many topcoats to get a smooth surface. Do you think just "too many coats" is the problem?

Thanks,
Jim

[Prashun Patel]

Just looks like too many coats of shellac to me. Shellac is usually forgiving - especially in the spray can form. Are you spraying too close? That can cause orange peeling too.

I'd try this: Moisten a rag with DNA and try to massage out those craters. Don't worry about the sheen dulling. If that doesn't work, use 220 sandpaper on a block to level the surface. Once you get it all level, then give it a light spritz of shellac as a final coat to fix the sheen.

[Scott Holmes]

Another option to add to Prashun's instead of adding more shellac (you already have too much) When you finish sanding you need to "pad" the shellac with a linen or lint free cloth that has just a bit of mineral OIL as a lube. Here is a link to how to properly "pad" shellac...

First link is How to make a pad. http://www.hardwoodlumberandmore.com/Articles/ArticleViewPage/tabid/75/ArticleId/14/Making-and-Using-a-Pad-for-Shellac.aspx

You already are to the stage of refining the finish not still adding shellac. This link will tell you how to refine it read the whole thing but you will start at "step two"

http://www.hardwoodlumberandmore.com/Articles/ArticleViewPage/tabid/75/ArticleId/15/Applying-Shellac.aspx