Working Sweet Chestnut

discussion of the niceties of turning on a bow, bungee or pole lathe.

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Re: Working Sweet Chestnut

Postby markclay » Mon Mar 23, 2009 11:16 am

Haven't tried it myself but lemon juice may also work, it should have the same effect on the stains as it does on tannin in your tea!

Re: tools a regular wipe down with an oil rag should do it or some soapy rag
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Re: Working Sweet Chestnut

Postby pedder63 » Thu Jul 04, 2013 8:57 am

Interesting post. Does anyone know the cause of the canary yellow patches that sometimes appear in sweet chestnut - I've asked loads of people and never got a definitive answer. It seems to develop on exposure to the air, and is kind of sulphurous in colour?
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Re: Working Sweet Chestnut

Postby ToneWood » Sat Jul 13, 2013 3:47 pm

Re. Yellow Stain:
I know what you mean, I saw it last week for the first time in two pieces of sweet chestnut that I split. I removed most of the bright yellow wood with axe and draw knife because there wasn't that much, it looked odd and I didn't trust the quality of the wood in the areas concerned (which were unusually wet) - I figured it might be due to some kind of disease/rot/injury although I suspected it was more likely some kind of sap.

Re. removing tannin stains from tools
BTW I just polish off the tannins after use as part of my regular stropping regime. I might start with a well-worn 600 grit sharpening stick or might just move straight to a leather strop stick with metal polish (e.g. autosol) or, more recently, white polishing compound (green would usually be good too - a little coarser). Brasso wadding works (tried it today), liquid might work better. I think Brasso has something like ammonia in it that is usually pretty good for stain removal. White vinegar (mild ascetic acid) would be worth a try (as oxalic acid appears to work) - our local market's vegetable stall sells 5 litre containers of the stuff for pickling, probably quite cheap when bought like that; white vinegar is becoming popular as a "safe" household cleaner again -- my local hardware store now sells it in pump sprays.

re. removing tannin stains from hands
I just use a lot of soap and hot water to remove it from my hands and, if it is particularly bad, a nail scrubbing brush. If some still remains on my hands after a couple of thorough "going overs" - using multi-stage hospital technique - then I figure it will do no harm and just let it wear off. I wouldn't put WD40 on my hands (kerosine & white spiriti?) - you could try Swarfega although that was also shown to contain carcinogens more than 30 years ago, it is probably much less harmful than the dirty engine oil that it was made to remove but probably not less than chestnut/oak tannin, so I don't use it for that. You might consider applying barrier cream to your hands before starting work - I do this when dealing with very oily jobs, the (pink) stuff I use dries on quite well, so you don't loose your grip. I suppose gloves are another option if it really bothers you that much but...
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Re: Working Sweet Chestnut

Postby HughSpencer » Mon Jul 22, 2013 10:28 am

For those looking to protect their hands rather than their tools. Sudacreme - used on baby's bottoms makes a good barrier cream. If you want a cheap supply of it you can by it by the bucket load from farm supplies as udder cream for cows - its the same thing and it is pretty safe if it gets on your sarnies.

Auxalic acid is indeed found in rhubarb leaves - don't ingest it as it is hard to cope with the squitters when camped out in the woods.

I suggest a little chemistry is in order here.
What is the discolouration?
Do we know of similar reactions?

Makers of Oak furniture used to hang their wares in horse stables. This darkened the Oak. The ammonia - strong alkaline, reacts with the tannin - a weak organic acid to leave a neutralised substance (a salt) that darkens the surface of the wood.

To verify this you could do what my father did. He placed an oak object in a plastic bag and also placed an uncorked bottle of ammonia 880 (very strong) in the bag and sealed up the bag. Next day the oak was almost ebony coloured.

The tannin on your tools and skin is reacting to an alkaline present to make the blue/black mess. If you don't clean it off the tools they will rust since you are leaving a salt in very close chemically bonded proximity. This salt will attract moisture from the air (deliquescence) and then it reacts with the metal.
Either protect from close contact with the tannin (wd40 etc) or use an acid that is stronger but does not create a salt that binds tightly to the metal, e.g. lemon juice or auxalic acid to clean it off frequently. Or provide an alternative alkaline for the acid to react with e.g. soap. Whatever you do, you must put the tools away clean and dry. Don't leave them for a moment longer than can be helped.
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Re: Working Sweet Chestnut

Postby monkeeboy » Tue Jul 23, 2013 7:17 am

I can't really understand why anyone would really need to remove tannin stains from their hands.
Personally, I quite like it, especially after peeling oak bark.

Makes me feel like I've been working!
It's also quite a good conversation starter.

It's not dirt after all, it won't kill you...
Excessively scrubbing your skin is not healthy, especially with nasty chemicals.
Personally, I would use a natural skin conditioner just to help with hard-working hands, like propolis, fermented papaya, comfrey, olive oil etc

And if you use your tools frequently then it doesn't get a chance to build-up and do any damage.
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Re: Working Sweet Chestnut

Postby jrccaim » Wed Jul 24, 2013 6:25 am

Of all the things that are toxic these days (there are many of them) plain old soap and water are way, way, down on the list. Good stuff. For tools you can go a bit further and use a detergent, also known as washing-up liquid, to remove stains. Works fine. I prefer not to use an abrasive. Just me. But if you must use one then the stuff used to scrub sinks will work too. It should be mild. Too much will do your edge in.I could give you USA names but perhapes useless in the UK. Dry the tool after scrubbing. There are two tool (amd hand) cleaners I will mention. One is borax. . It adds kick to any soap or detergent. The other is plain old washing soda. Even baking soda (a milder, and somewhat puirified, version of washing soda, notning more than Sodium bicarbonate) will do. This stuff will remove rust. It will remove stains. It willl even remove tea or coffee stains from cups an other cookware. It takes its time. 24 hours is what I do, but I have restored several old chisels with it. Of course, it cannot remove pitting, but that is an aside.
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Re: Working Sweet Chestnut

Postby ToneWood » Wed Jul 24, 2013 12:54 pm

Interesting. Hadn't realized that washing soda (mild alkali) removes rust, vinegar does (mild acid), a tip from Nic - works well. I live in a hard water area and we often add washing soda to the washing machine/dishwater/washing bowl to soften the water, which allows soap/detergent to be more effective & helps reduce/prevent the build up of limescale (some homes have salt-based water softeners installed - uncommon here tho').
Re. Borax, I haven't seen Borax around but my local hardware store recently started carrying "Borax substitute":
Which made me wonder: why "substitute"? Checking Borax on wiki, I found this:

Borax, sodium tetraborate decahydrate, is not acutely toxic.[22] Its LD50 (median lethal dose) score is tested at 2.66 g/kg in rats:[23] a significant dose of the chemical is needed to cause severe symptoms or death. The lethal dose is not necessarily the same for humans.

Sufficient exposure to borax dust can cause respiratory and skin irritation. Ingestion may cause gastrointestinal distress including nausea, persistent vomiting, abdominal pain, and diarrhea. Effects on the vascular system and brain include headaches and lethargy, but are less frequent. "In severe poisonings, a beefy red skin rash affecting palms, soles, buttocks and scrotum has been described. With severe poisoning, erythematous and exfoliative rash, unconsciousness, respiratory depression, and renal failure."[24]

Borax was added to the Substance of Very High Concern (SVHC) candidate list on 16 December 2010. The SVHC candidate list is part of the EU Regulations on the Registration, Evaluation, Authorisation and Restriction of Chemicals 2006 (REACH), and the addition was based on the revised classification of Borax as toxic for reproduction category 1B under the CLP Regulations. Substances and mixtures imported into the EU which contain Borax are now required to be labelled with the warnings "May damage fertility" and "May damage the unborn child".[25]

More on Borax substitute @ ... oes-it-do/
More on green cleaning:
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