Benchcrafted, The French Oak Roubo Project

[Dangermouse]

"Over the past couple years and after several trips to a Roubo-esque millwork shop in rural Georgia, we've been able to source enough French oak to build several benches that almost exactly match Roubo's description of his joiner's bench from Plate 11. The slabs are 5-6" thick, from 18 to 28 inches wide and around 19' long. They have been air drying for over 10 years. But here's the kicker. Some of these trees are directly from the grounds of Versailles, and were likely growing in the late 18th century. We haven't counted the growth rings, but there's a good chance these trees and Roubo were contemporaries."

My question would be if the bench top is Oak, surely the tannin in the wood will make any tool in contact with it stained blue/black and stain the wood too. What do you guys think ?

Here is the link to the project and a video of making it
http://benchcrafted.blogspot.co.uk/2013 ... oject.html

http://benchcrafted.blogspot.co.at/2013 ... oject.html

 

[Random Orbital Bob]

Sounds like the wood is gorgeous Danger. But either I'm missing something or I can't see why oak would stain anything. Everything I've ever made or bought from oak which includes English, French and American hasn't ever shown any inclination to give up any staining. Neither has this been the case whilst machining it and that includes turning it green when I imagine the tannins would be at their most potent.

So as I say, unless this is a downside of oak I'm completely unfamiliar with I reckon it should be fabulous for a bench.

 

[Cheshirechappie]

I'm speculating a bit here, I don't really know - but could there be a time element in the development of tannin staining? An iron hinge screwed to an oak door for several decades will develop staining, but a sawblade left on an oak benchtop overnight maybe isn't in close enough contact for long enough for staining to be noticable - especially if the wood is bone dry.

 

[bugbear]

I'm speculating a bit here, I don't really know - but could there be a time element in the development of tannin staining? An iron hinge screwed to an oak door for several decades will develop staining, but a sawblade left on an oak benchtop overnight maybe isn't in close enough contact for long enough for staining to be noticable - especially if the wood is bone dry.

I think the latter is key. Staining requires either time or moisture.

Planing green oak = black blade and black sole.

BugBear

 

[Dangermouse]

The thing is I have a load of Oak that I have been air drying for 20 years and was thinking of making a bench from some of it, but was a bit concerned. I think I will do an experiment on a off cut, lay a piece of clean steel on it and see what happens over what time. I think Bugs has it right when he says its to do with moisture being present.

 

[Richard T]

Oak and iron have gone together for many centuries in very close unison and the marks that appear are just part of it.
I think it must be quite recently that people have taken an aversion to iron stained Oak - when I think of all the church doors and other things of similar age I've seen, probably made when green, with scores of clenched nails, hinges, straps...
For a bench of such provenance, I wouldn't worry about it at all DM.
I don't know about just leaving something resting on it to test it but a Roubo holdfast jammed in it for any length of time .. it's bound to happen but I'd let it if it were me. It's not going to affect the work or the benches ability.

 

[Random Orbital Bob]

Couldn't agree more

 

[Dangermouse]

To be honest, I was more concerned with my planes and tools getting turned blue/black. I agree a bench that shows its history is a fine thing.

 

[Paul Chapman]

To be honest, I was more concerned with my planes and tools getting turned blue/black.

I've used lots of oak and it's never had any effect on my tools and I don't know of anyone who has had any problems with it. What you do need to be careful of is not to use steel wool on oak, because small pieces of the steel wool can become embedded in the oak and, over time, black spots will appear around where the steel wool is embedded.

Cheers :wink:

Paul

 

[AndyT]

Come on then DM - time to get on with a bench build wip!

 

[Shrubby]

I've had reactions from oak and iron tools giving me black hands , the stuff had been 10 years acclimatising in a dry workshop. I put it down to sweat on my skin picking up tannins and reacting with ferrous tools.
I would hope someone making a bench would seal it with oil which should seal the tannins in
European benches tend to be Beech which can be steamed or impregnated with linseed oil to stabilize it

Ps. I have seen tracker organ makers soak freshly felled oak logs in water ponds for a year before the drying process starts = I'll have incvestigate this further
Matt

 

[Paul Chapman]

Dangermouse, did you see this entry in Jeff Miller's blog, taken during the building of the Roubo benches http://furnituremaking.com/wordpress/?p=387

Cheers :wink:

Paul

 

[whiskywill]

This boar's head, in my local pub garden, was carved form a lump of oak with a chainsaw, and was rubbed over with vinegar and iron filings. It turned black in a very short time.

 

[Dangermouse]

Come on then DM - time to get on with a bench build wip!

As it happens I am building a new bench now. Beech top, reclaimed Victorian pine legs and frame. I got a nice Parkinsons Perfect no15 vice the other day and gave it the treatment, now works like new.

Still a fair bit of work to do, but should be finished soon------ish (hammer)

 

[Corneel]

You often see old oak rafters, 30x30 cm for sale, for not too much money. That should make a very nice Roubo. Of course, I don't need a new bench, and I don't have time to make one. Still....

 

[woodbrains]

Hello,

Since beech is about half the price of oak, why do you get some beech to make the bench and save the oak to make something nice?

It makes more sense to me to use a more economical timber for the bench and save he more expensive wood for projects. You will have to buy some wood to make stuff, after all. Besides, beech is less likely to split during use.

Mike.

 

[G S Haydon]

Like shrubby said hot hands on oak makes them go purple . A tough one to explain when on a night out on the town......
I see no problem with the oak bench staining during normal work, that said I would not know for sure as I work from a sheet of OSB.......

 

[Dangermouse]

Dangermouse, did you see this entry in Jeff Miller's blog, taken during the building of the Roubo benches http://furnituremaking.com/wordpress/?p=387

Cheers :wink:

Paul

Yes now that's a bit worrying ! so I think as Mike said when I get round to making my next bench later this year or in the spring I'll get beech for the top and use the oak for other things.

 

[Paul Chapman]

Dangermouse, did you see this entry in Jeff Miller's blog, taken during the building of the Roubo benches http://furnituremaking.com/wordpress/?p=387

Cheers :wink:

Paul

Yes now that's a bit worrying !

I wouldn't worry about it too much unless you find that you, personally, have a problem when working with oak. Some people have a problem which is generally known as "rusty finger", where perspiration from their hands causes their tools to rust. I've never had this problem, and nor do most people, but I know some woodworkers who do. I suspect the problem with those in that picture is more to do with their particular perspiration reacting with their tools and the wood than anything else.

Cheers :wink:

Paul