Finish for Spalted Sweet Gun

[Edward Bartimmo]

I have a nice spalted sweet gum bowl that has nice backline spalted as well as a pale purple marbled spalting throughout the wood. The wood is a little soft and prone to tear out and crushing. The final form will require sharp tools with a gentle touch as well as some quality time with sandpaper to remove any tears or other blemishes. The piece is pretty enough for the extra effort. To offset some of the softness of the wood I would like to use a finish that would strengthen the wood fiber. A wipeon varnish, such as Waterlox, would penetrate the wood deeper than a lacquer. I am a little to far into the project to start testing finishes on the surface of this piece and I don't have another piece with similar spalting to test on...

I have a very specific question that I would like to ask. Has anyone dealt with a similar piece of sweet gum and how did the finish change the spalting colors?

Thanks

[Greg Bolton22]

I had a much smaller piece that was almost falling apart. I had to surface treat the entire piece with thin CA just to be able to get finishing cuts without tear-out. I then sanded back to bare wood and used danish oil and buffed. The CA had penetrated enough to harden the wood but did not prevent the oil from soaking in. The color was even better after the oil, the regular wood was richer and the spalting lines stayed black. This might not be practical for a good sized bowl but something to consider. I agree that the extra effort is worth it on these pieces. It is the shortest tea-light holder near the center of the picture. All of the other spalted pieces are oak and not as nice as the gum

212473

Greg

[David E Keller]

I haven't lucked on to any spalted sweet gum, but shellac has served me well as a wood fortifier for final cuts in spalted maple and sycamore. It does add a bit of an amber hue depending on the flakes you mix, but so does an oil finish.

[Bernie Weishapl]

I have had some really pretty spalted maple that had a lot of soft wood. Sharp tools as you have noted and sanding left the surface pretty smooth but the wood was still soft. I soaked it with watelox and that stablized it pretty well. Like yours to pretty to put in the firewood pile.

[Dennis Ford]

I have found that lacquer changes the color less than other finishes. Lacquer based sanding sealer does a good job of stiffening the fibers especially if you thin the first couple of coats. I prefer Belen's but Deft sanding sealer is not bad at all. Regular lacquer can be used as a sanding sealer but it is much more difficult to sand (gums up sandpaper). Many oil based finishes or shellac will also work but they tend to add an amber hue to the color.

[Edward Bartimmo]

I have found that lacquer changes the color less than other finishes. Lacquer based sanding sealer does a good job of stiffening the fibers especially if you thin the first couple of coats. I prefer Belen's but Deft sanding sealer is not bad at all. Regular lacquer can be used as a sanding sealer but it is much more difficult to sand (gums up sandpaper). Many oil based finishes or shellac will also work but they tend to add an amber hue to the color.

Dennis,

I was hoping to hear from you... You probably have handled spalted sweet gum more than most. Any idea why the sanding sealer is less "gummy" then straight up lacquer?

Thanks