BOXWOOD: Natural vs Acid stained

[glasba]

Hello,

I am just curious about what is real advantage and reason why most makers "acid stain" boxwood when they make chanters or sets ? Is it just for aesthetics, since they prefer the look of more Brown/Orange color or it is to make it more resistant to the dirt and sweat of hands, fingers ect... I saw some flutes and chanters in both versions and both they look same beautifull to me. I also noticed that Acid stained chanters develop some light areas, since the stain worn out, especialy on the positions where the fingers touch the wood contantly - around holes, so for this aspect Natural "just oiled" boxwood would be better idea Imho.

Thanks a lot for any comments, Regards, AA

[boyd]

I think boxwood that has been left to change colour naturally is SO pretty.

Staining it just makes it look like a darker wood, its like a blonde wanting to be a brunette. You can do it....but why not just be yourself?!!!

If commissioning a new set, I guess the buyer can choose.

I don't think the staining adds any extra musical or other qualities.
(Dunno if it affects box's propensity to change shape when temp and humidity change?)

Boyd

[billh]

In my experience acid staining causes the boxwood to resist dirt much better. If it's done properly, it shouldn't lighten due to wear. Some discoloration will happen with stained boxwood, but less than with natural i.e. unstained boxwood. You can see this with old instruments as well as new ones. Unstained boxwood will attract and show dirt very badly unless it's relatively thickly shellac'ed/varnished, which brings its own disadvantages (flaking and wear of the finish, etc.). Acid staining can range from quite light, giving a yellow tone, through various oranges, to a deeper, browner color, depending on the wood and how it's done.

One part of what happens with acid staining is that the nitric acid reacts with the outer surface of the wood to form nitrocellulose, a natural polymer finish - but one that seems to be integrated into the wood itself and thus not prone to flaking.

Bill

[uillmann]

The most satisfying results I got finishing box was a laborious, time consuming and lengthy process of flooding the wood with linseed oil, followed by a drying period, and then a residue removal and re-polishing. It takes many months for the absorbed oils to harden, and the process is then repeated, at least 4 or 5 times. There should be no flaking whatsoever, as no buildup of hardened oils remain on the surface. And there should be relatively little dirt staining, as boxwood pores are quite small, and when they are full of the hardened linseed solids, there is no place for the dirt to get trapped. Eventually, the wood darkens to take on a deep honey hue, and will take a great polish. After a few years of handling, any accumulated grime is easily wiped away with the occasional re-oiling.

[Tony]

I've heard the term "fumed" where the wood is placed in a chamber over a tray of acid.
The fumes of the acid penetrate the wood and react with it, making it darker and hardened.
Acid-stained is the same process... Yes? The acid (liquid) never touches the wood.

German oak flooring is treated this way.
Their translation is "smoked" but it too is the same process. No smoldering coal/wood is involved.

I know of a pipemaker who uses French-Polish or PAD-LAC (brand name from constantines.com) to seal his pipes. It's shiny, smooth and needs no maintenance. The wood didn't darken around the tone holes.

[ausdag]

I have a friend who darkens his wood by fuming it with household amonia. This seems a safer and effective opition to acid. Not having tried it myself though, does anyone know what the advantages of acid fuming are over amonia?

[rorybbellows]

If I remember correctly there was an article in An Piobaire a few years ago about staining boxwood by exposing the wood to human urine fumes, which is a method developed from the wool processing trade.You'd have to check the article but I think some fermenting agent had to be added to the urine and then the instrument would be suspended over the fuming urine and was then placed in a fuming box for a couple of days.
There was quite a heated dedate at the time as to whether Irish urine(grain based) or European urine(grape based)was the best for the job. Like everything else it probably comes down to personal preference. If you want to try the european,French urine is probably the best as the high garlic content of Italian produces mixed results and the oil content of greek makes it unworkable. Under no circumstances should you use Brirish urine as it is just far too weak. Try ringing NPU as they may have a stock of some french ,otherwise if you're ever in France try standing outside a public toilet and asking for donations . I have found the French to be very willing to donate urine when asked. By the way dont get started on the whole male or female thing or this thread will surely be locked.

RORY

[Cathy Wilde]

I seem to be a boxwood magnet; I've now collected both stained and unstained flutes as well as a half-set that's a mix of stained and unstained -- the chanter & mainstock constituting the "au naturel" portions. I agree with Bill that unstained box shows the dirt around the fingerholes (I just wipe with a damp cloth, but still it gets a bit manky). Anyway, overall I prefer stained.

I have a flute that was stained or fumed with nitric acid, and that to me is as pretty as it gets. It's a warm red with the yellow undertones in the grain coming through. My unstained (but oil-sealed) boxwood flute is darkening with age and it has a lovely finish, but it's so very blonde that I'm a tiny bit embarrassed by it.

Finally ... and this might be an hallucination, or maybe it's just different logs ... but it seems the grain on my stained instruments/instrument parts is tighter somehow; a tiny bit less porous.

THAT said, both the red flute and my baritone drone are slightly warped ... and they're both stained. ????? Maybe just a coincidence, though.

Ah, who knows? But I still like that nitric-acid red. Especially over dirty-fingers grey. !!!

[uilleannfinlander]

I treated my box fullset myself by nitric acid fuming.Nice brownish colour. 10% liquid+ tooth etc. brush and hair dryer.To get good surface need carefull job removing old laquers etc. also all keys must be taken off.After colouring, wipe linseed oil and then polishing with machine with softwheel + wax.

[billh]

Boxwood can be 'fumed', but it can also be stained by applying (preferably slightly dilute) liquid nitric acid followed by gentle warmth. The acid will react fully, eventually. While the fuming method may seem less dangerous, the fumes are actually the most hazardous part so I think the liquid method is considerably safer; good ventilation is a must in any case.

Ammonia staining is another matter; ir relies on a reaction with tannins in wood, so it works well with some timbers but poorly, if at all, with others. As far as I know it doesn't do a whole lot with true boxwood (buxus sempervirens). I reckon the urine staining method relies on ammonia - can't say I've tried it!

Uillmann's observation about linseed oil finish echoes my experience, insofar as it's a very robust finish that isn't prone to flaking if applied very slowly in hundreds of coats over time. Spike lavender oil is a natural drier and helps the oil polymerize, if anyone wants to try; I've used this sort of finish over the top of acid staining with good results, but it really takes patience.

- Billl

[Mike Hulme]

The French violin bridge manufacturers, Aubert, used horse urine to darken down their newly cut bridges. It works very well, but is a slow process. Fuming boxwood with nitric acid is better, and I neutralise the acid fumes with ammonia (acid + alkali = salt + water). The concentration of acid is important; the more concentrated it is, the less time your wood should spend in its' fumes.

If you are going to use linseed oil, then make sure it is the raw variety; boiled linseed oil has dryers in it and will not work. Flaxseed oil, available from healthfood shops is raw linseed oil and can be used straight from the bottle. Walnut oil, which is also a drying oil like linseed, will also work well, and has the advantage that you can use it as a salad dressing.

[hpinson]

This is a bit unrelated, but what are some common practices for enhancing the look of Castillo Boxwood / Lemonwood, which by itself is quite plain? Same as describe here? Or some other method?

[Cathy Wilde]

Y'all let me know if you need any horse urine. THAT I have an abundance of. In fact, being near Churchill Downs, I can probably even get you Kentucky Derby winner samples if you send a hefty love offering for a groom or drug tester ... Pedigreed pipe pee. I like it!

As for the nitric acid, that makes sense, Bill. I remember Michael Clarkson once mentioning the alley behind Sam Murray's old Belfast shop where flutes were just sitting in buckets of nitric acid ... my old boxwood Murray flute is the lovely red one.

[glasba]

Thanks for all the comments. Acid staining does make very nice looking finish, but I gues I prefer the natural beauty of Boxwood. And probably if you take good care, by playing with clean hands and once a week cleaning with cloth and sometimes polishing with nut oil then it should be just Ok.
AA