Fuming white oak issues

[harleydog]

I have a issue with the fuming process. I have built a quarter sawn white oak end table and am in the process of testing the finish. The project is in the mission theme so I want to try fuming the wood. I took a couple of the cut off's from the project and did testing. Different times I left the wood exposed to the 28% ammonia gas, 5 hrs 12 hrs and 24 hrs to start. All of the finishes cameout way to dark and with a slight green tint to them. I have read that temperture can effect the finish so I am in the process of trying it again for 1 hr with a heat source to keep the temp warmer which according to the articals that I read online will result in a more red finish. Has anyone ever had this issue, if so what do I do to get that traditional brown mission finish. Thanks in advance.

[thewoodwhisperer]

I have always supplemented the color with a little dye, stain, or glaze. The fuming can be somewhat unpredictable and it may not be even. So supplementing with a little color can get you right where you need to be. In fact, I used to follow up my fuming with a coat of amber shellac, a brown glaze, another coat of amber shellac, and then a coat or two of a satin wiping varnish. Beeeeutiful!

[harleydog]

I have always supplemented the color with a little dye, stain, or glaze. The fuming can be somewhat unpredictable and it may not be even. So supplementing with a little color can get you right where you need to be. In fact, I used to follow up my fuming with a coat of amber shellac, a brown glaze, another coat of amber shellac, and then a coat or two of a satin wiping varnish. Beeeeutiful!

Thanks for the advise Mark. I tried to adjusting the heat at which I was fuming and it did not come out the way that I was hoping for. While it did get rid of the greeen tint, it was not dark enough or even across the test piece. So I am going to use dye and amber shelac to get the right finish. I will have to try it again in the spring.

[Gregory Paolini]

I have a issue with the fuming process. I have built a quarter sawn white oak end table and am in the process of testing the finish. The project is in the mission theme so I want to try fuming the wood. I took a couple of the cut off's from the project and did testing. Different times I left the wood exposed to the 28% ammonia gas, 5 hrs 12 hrs and 24 hrs to start. All of the finishes cameout way to dark and with a slight green tint to them. I have read that temperture can effect the finish so I am in the process of trying it again for 1 hr with a heat source to keep the temp warmer which according to the articals that I read online will result in a more red finish. Has anyone ever had this issue, if so what do I do to get that traditional brown mission finish. Thanks in advance.

I do some ammonia fuming, but I try to limit it to small pieces, and couple that with a disclaimer that I can not control the results.

Here's the problem with fuming: It's a chemical reaction between the amonia fumes, and the tannins in the wood. I like to compare tannins in wood, or the tree, as being a lot like body fat on us. Some parts of us have more, and some have less. So tannin content can vary from tree to tree, board to board, and even within a single board. Since the color is a result of fumes contacting tannins, the results can be sporadic, and inconsistant.

I usually leave my pieces in the fumes for 4 to 8 hours - No need to let them sit much longer, unless you're going after an ebonized look. Again, it will depend on tannin content.

The green cast you're getting is common. You can cancel it out by using some paste wax with some red tint applied to it, or a nice mahoganhy wax. As far as getting the classic reddish brown antique mission color we all desire while fuming - Well, at risk of sounding cocky, just wait 100 years. The chemical reaction will continue for quite a while, eventually evening out, and giving you that wonderfull mission color. I wish it were simpler to get that great result, because Fuming is actually really easy - It's the easiest stain I have ever used....

Also, sometimes the fuming process will impart an Aroma in the piece that pets may want to try and cancel out, in a way that only the animal kingdom understands....

I will fume if a client wants it - But I'm really upfront will all the pitfalls. For consitancey, I go with dyes and stains. I can get you my recipe if you'd like... Just shoot me an email.

-gp