Gill: Ebonizing wood

[Marsha]

Hi Gill: Where can I find your tips for ebonizing wood?
When Bob published it in the magazine did he delete the post?
Do you by chance know what issue it is in?
and just one more, Is your recipe similar to Trouts?
well maybe another one! Does your recipe work on all types of wood?
TIA
Marsha

[Jediscroller]

Hi Marsha,
I'm not Gill, but the thread where she was nice enough to share her tea idea is here.

[Gill]

Thanks, Kevin .

Marsha - I believe the tip is in the latest SSW&C issue, although I haven't received my own copy yet so I don't know for certain.

Making the vinegar solution is dead easy and completely slap-dash; just put a few old bits of iron in some vinegar and give it a couple of days to mature before use. Make sure that the iron you use doesn't have the protective layer that's applied to some nails and screws. You can do this by rubbing a file over them, although there's no need to use good quality iron anyway - a bit of rust seems to help the vinegar penetrate the metal more efficiently.

I've only tried the technique on ash so far because I have an abundance of it, but there's no reason why it wouldn't work on other woods.

Gill

[Marsha]

Kevin: Thanks very much for the link to the previous thread, it is very informative and a technique I will be trying in the near future. I have a request to make a chess set from ebony, and that ain't gonna happen, the woods too expensive and very difficult to cut on a scroll saw, especially in the 1 1/2" thickness you need for chess pieces. I will do a test piece on pine and see if it works. However I've read the article by Mac Simmons in this issue and I can't find any mention of the tea technique, so I have another question.

Gill: if I understand your tip correctly,
You put tea on the wood to create the tannin, so the vinegar solution would work on the wood! You didn't just use tea and vinegar?

Thanks
Marsha

[Gill]

I’m not a chemist and I haven’t read Mac Simmons’ article, so forgive me if my understanding of the process doesn’t tie in with his explanation of the ebonizing process. For what it's worth, I've been told my technique gets mentioned on page 28.

Tannin and iron react to produce a black stain. This is why you should never use iron hardware when you’re working on woods that are high in tannins, such as oak. At first, you won’t notice anything wrong but as time passes an ugly black mark will appear on the wood where it is in contact with the iron. Most woodworkers try to avoid this. Nevertheless, there are times when we wish to use this property to our advantage to create an ebonised effect. The big problem is controlling the reaction and making it spread evenly throughout the wood without having great big lumps of iron, which probably aren’t part of the project anyway. This is why we make an iron solution by putting the iron into vinegar and allowing it to dissolve. After a little while, the acid in the vingar dissolves the iron at a molecular level and it can be applied to the wood without the inconvenience of having visible chunks of metal.

Just applying vinegar without the iron wouldn’t work – the vinegar is merely a carrier for the iron. So you have to create an iron-vinegar solution.

Some woods don’t have a high tannin content, so we need to raise their tannin levels in order to ebonise them with the iron-vinegar solution. Tea has a very high tannin content; by painting it onto the wood and letting the wood absorb it, we’re raising the wood’s tannin content so the iron-vinegar solution can penetrate the wood deeply and evenly.

Hope this clarifies things .

Gill

[Marsha]

Gill: Thank you very much for glarifying this technique for me, and you're right it is on page 28, I just didn't read that because it's with a pattern "Witch's Brew" by Lora Irish.
Thanks Again
Marsha

PS; you sound like a chemist with that great explanation.
Marsha

[MacS]

Woods that are not high in tannin will produce various colors of yellowish browns when the vinegar acid stain is used on these woods

Even when the "tannin tea" is used on woods that are low in tannin you will get darker colors, but they are more on the brownish black side then on the black.

Because, their are so many different woods, the only way to really know how the woods will turn out, you need to make up start to finish samples.

Actually, Ebony is a blackish brown wood, the woods that are high in tannin look black, whereas, those woods low in tannin, where you induce the tannin will look dark brown not black. (this would depend on the type of tannin you induce)