I need finishing advice for a very thin vessel with voids and wormholes

[Charles Henderson]

I have a turned vessel that is ready for finishing. It is an Elm burl that is absolutely full of wormholes and voids. It is also thin enough to be quite delicate.

My question is what should I use for the finish? I need something very thin that won't gunk up in the voids and holes, and I also need something that won't require any sanding. Am I stuck with Mineral Oil?

 

[Richard Baker]

Spray lacquer.

 

[Bill Boehme]

Spray lacquer (echo).

Definitely don't use mineral oil. If you do want the soft sheen of an oil finish, use a drying oil like linseed oil, tung oil, or walnut oil. My favorite oil finish is walnut.

 

[Charles Henderson]

I would rather not use spray lacquer. I'm looking for a very natural sheen.

Bill, why did you say "definitely don't use mineral oil"? I understand it doesn't dry and requires reapplication, but I still use it on some things.

Maybe I've just had bad luck with antique, walnut and tung oil finishes, but I seem to get too much buildup that needs to be buffed, or even sanded. I won't be able to do any sanding or buffing because the turning is too delicate. I also don't want it gumming up the tiny wormholes. Should I be thinning the oils?

I have some BLO, but haven't used it much. Would it dry without streaks and gunk? Maybe I should just use a sanding sealer, and leave it at that. Sorry, just a little nervous about ruining it in the final stage. I'm surprised it survived so far.

Thanks for the help

 

[Charles Henderson]

Here's a sneak peak

When I say delicate with a bunch of wormholes and voids, I'm not kidding

 

[Robert Manning]

Three options come to mind, Charles.

1. Some finishers thin the drying oils Bill mentioned with up to four parts thinner such as odorless mineral spirits.

2. A one pound cut of shellac, which is one of my favorites. When mixed with pure sugar cane alcohol, this is non-toxic. The methanol in denatured alcohol can damage your optic nerve if you breathe it.

3. A can of Krylon matte acrylic spray which is very flat and forgiving and easily touched up. Smells really bad.

These are the types of finishes that allow you to "sneak-up" on the look you want.

I might add, whenever someone asks about my finishes, I encourage them to get a copy of Bob Flexners book on Wood Finishing, which demystifies a lot of misinformation about finishing.

 

[Bill Boehme]

I would rather not use spray lacquer. I'm looking for a very natural sheen.

Bill, why did you say "definitely don't use mineral oil"? I understand it doesn't dry and requires reapplication, but I still use it on some things.

Maybe I've just had bad luck with antique, walnut and tung oil finishes, but I seem to get too much buildup that needs to be buffed, or even sanded. I won't be able to do any sanding or buffing because the turning is too delicate. I also don't want it gumming up the tiny wormholes. Should I be thinning the oils?

I have some BLO, but haven't used it much. Would it dry without streaks and gunk? Maybe I should just use a sanding sealer, and leave it at that. Sorry, just a little nervous about ruining it in the final stage. I'm surprised it survived so far.

Thanks for the help

In addition to Flexner's book that Robert mentioned, I like Jeff Jewett's book, "Great Wood Finishes", Michael Dresdner's Book, "The Wood Finishing Book", and especially "Finishing Methods of Work", edited by Jim Richey which is a collection of finishing information from 25 years of Fine Woodworking Magazine. Here is an excerpt by R. Bruce Hoadley from the last mentioned reference regarding the use of mineral oil.

"I do not consider mineral oil a finish. It offers little protection to the wood since it does not polymerize and would therefore be neither physically stable nor a barrier to moisture. If applied to raw wood, it would enter the cell structure, but changes in temperature and atmospheric pressure could result in its bleeding out on the surface."
​

Hoadley is the author of the two well known texts, "Understanding Wood", and "Identifying Wood".

If you are having problems with gummy buildup of oils like linseed, tung, or walnut then they are definitely not being properly applied. It should not be mopped on like paint or varnish, but rubbed into the wood and then any excess wiped off after about ten minutes. When I apply a walnut or tung oil finish to a bowl, I will soak a rag in the oil (usually I just pour some oil into the bowl) and then smear it around on the inside and outside. I will do this for a few minutes and then let it sit for ten or fifteen minutes. Finally, I will get a clean dry cloth and wipe the surface dry. After about thirty minutes, I will wipe it dry again to take care of any oil that has leached out. By that time the bowl should be fairly dry and I will then let it sit for about 24 hours and it is normally ready to handle by then. There is rarely any need for another oiling. Definitely do not do any sanding or buffing after oiling the bowl or the finish will be muddied. All of the sanding must be done BEFORE the oil finish is applied.

If applied properly a lacquer finish can look as nice as an oiled finish. It is important to not apply a heavy coat or apply it in the hot sun or there will be problems like runs, sags, blush, orange peel, etc.

 

[Joe Greiner]

The voids and wormholes don't have to be the same finish as the turned surface, and probably can't be anyway. Although it might not be your cup of tea, I've accentuated voids with contrasting paint - bright red, in fact. Then a sprayed finish overall. For a more natural sheen, semi-gloss or clear satin polyurethane isn't too shiny. Many, many light coats are better than one or two heavy ones, and if applied less than two hours apart, don't need sanding between coats. Even when sanding IS needed on the turned surfaces, the voids will have a different appearance anyway. And as Robert says, you can sneak up on it.

 

[john lucas]

I use minwax wipe on poly. It's thin, you can buy the glossy or the satin. It penetrates into cracks well if you slop it on in those areas.

 

[Hugh]

I vote for Krylon matt finish. You will hardly know it is there. Put it on lightly and no sanding.
Hugh

 

[Richard Coers]

+1 vote for matt or flat clear lacquer. One or two coats and you won't hardly know it's there. Some of the oils, like blo, will really darken the piece. But, maybe that's what you want. Two other things I don't like about some oils is bleed back on porous woods, and soaking through thin wood and keeping an odor on the inside of the vessel.

 

[Mr. Don]

Worm holes and voids/how to finish

Charles...you as usual, will be bombarded with all kinds of (mix this into that, and maybe get thus), I, for what it's worth, go for the spray-on matte or semi-gloss laquer...great for super fragile and keeps original color well...will yellow just a tad, but I have found it very acceptable, and a lot less work. Good luck, and post your results.:cool2::cool2:

 

[Charles Henderson]

Thanks to everyone for your input. I'll turn a test piece out of the same wood and try the Krylon matte lacquer on that first. I hope that will work for me. I think even wiping a finish on may be out of the question anyway, especially on the inside. It's just too fragile. I'm nervous every time I pick it up.I'll post a picture when I finish it in a couple of weeks.

Also, thanks for the book suggestions! Finishing is the one aspect of my turning that is definitely not up to par with the rest.