Hi Dean, the ebonised oak underframe is very black, I have never managed to get it that black mine always comes out sort of dark navy blue. A few hints and helps would be very gratefully accepted, I used the vinegar and wire wool method. Ian
Hi Ian,
I use the same method as you.
Are you making up the tannic acid?
My process for making the iron 'potion' is placing a tennis ball sized amount of (0000 or 000) fluffed up wire wool into a small jam jar (or similar) and then filling the jar near to the top with white vinegar (and covering the wire wool as much as possible).
Punch a small hole in the lid and then leave it to do its stuff - about 5 - 7 days.
I've found that if you use too much wire wool or it's too thick you end up with a murky green/brown liquid - not desirable at all. Also, you can end up with a soggy mess of wire wool in the jar where the chemical reaction has stopped. The potion seems to last for a couple of weeks whereupon the iron settles out of the liquid and you end up with a rust coloured liquid at the bottom and a dark liquid at the top. I think the top part is useable (I have some like this, but I haven't tested my own theory on that....), but the rusty stuff really leaves a nasty colour on the wood.....experience talking there...lol - and then it's a real pain in the backside trying to remedy that situation - so best not to end up there.
When the iron potion is ready it should be nice and dark. Make up some tannic acid by by boiling in water for 10 mins (sorry if I'm teaching to suck eggs lol) and then do the following:
1) Lightly sand with the grain (240/320 grit)
2) Brush the tannic acid onto the oak (it doesn't have to be cool - in fact the heat helps to open the grain a bit) and leave to dry - don't over saturate the wood, but don't be shy with the tannic acid either. Allow to dry.
3) Wipe off any excess dust.
4) Repeat steps 1,2 and 3 twice making sure tannic acid gets right into the grain.
5) Apply more tannic acid - only this time - just before all the tannic acid evapourates give it a little wipe to remove any excess liquid
6) Immediately apply the iron 'potion' and leave it for a couple of minutes and then smooth it out making sure all areas are covered evenly. Leave it to dry thoroughly.
Normally, once dry, you will get a dark blue/purple coloured bloom appear on the wood - this is good!
Get a lightly damp cloth and wipe off the bloom. Hopefully you will have ebonized oak.
I have found that sometimes you get white streaks (dried sap I think) in the grain which is really obvious. If this happens I use a fine brass wire brush such as a suede brush to brush all the sap out of the grain. Unfortunately you might have to go through the ebonizing process again.....a pain, but it does make a difference.
If you feel that the oak is not dark enough then re-apply some tannic acid and then the iron potion. Repeat this process in that order until you are happy. You do not have to repeat the whole ebonizing process, just the adding of the tannic acid and iron potion steps
Wipe off any residue and then buff the timber ready for the finish.
Finally, apply your preferred finish. If you use a wax/polish I suggest you use a dark one to avoid visible build up in the grain.
I hope this helps.....let me know how you get on
Cheers
Dean