white oak planking

[jnjwilson]

I've been watching Harold Burnhams web site as they plank the Ardelle with white oak.It looks like they are steaming all planks, I know it's done to make the plank easer to bend but is it also to impart a little stability to the wood since boiling seems to help remove sap from the wood.Do they use quarter sawn planks to reduse movement? Is the boild planks at "full" size as when in the water.I know normally planking stock is air dryed , how does boiling affect the procedure for planking as far as wood movement is concerned. Would love to hear from the burnham camp but i know others can fill me in also. thanks jnjwilson

[DCockey]

The WoodenBoat Forum would probably be a better place to ask your question.

[gonzo]

Steaming is only for ease of bending. Sometimes it is the only way to make a plank bend to a tight curve. It also sterilizes the wood, but that is a secondary benefit.

[Boston]

The WoodenBoat Forum would probably be a better place to ask your question.

I'm not so sure about that, I've had several bad experiences asking seemingly simple questions or expressing some pretty benign views over there, if you think there's grumpy people here wait till you bump into some of the wacko's over there.

I made a case for epoxy impregnated poplar and wow, what a freak show.

my take would be if your going to brave a wood question over there be ready for some psychotically strong opinions and a barrage of off the wall comments regarding your competence

best of luck
B

I've worked with white oak for years but never steamed the stuff, so I'm going t let someone else field your question

best of luck
B

[BriggsMonteith]

White oak turns into an almost rubber solid after soaking and steaming, like almost no other wood. which is interesting because softer, naturally flexably woods usually don't do nearly as well. I've never taken a moisture meter to wood after steaming it but it usually does seem incredibly dry.
-Briggs

[gonzo]

Oak needs to have a high content of humidity to steam bend. If it has been air or kiln dried, it needs to be soaked first.

[BriggsMonteith]

Yeah we used to soak it in the river for 3 days first.

[jnjwilson]

Thanks for the replies, but i'm not asking how or why to steam oak planking for bendability but as to the expantion and contraction of steamed oak planking and the hows and whys of putting it on the side of a boat. jnjwilson

[DCockey]

Originally Posted by jnjwilson

Thanks for the replies, but i'm not asking how or why to steam oak planking for bendability but as to the expantion and contraction of steamed oak planking and the hows and whys of putting it on the side of a boat. jnjwilson

I've never had a problem with the WoodenBoat forum. I do stay out of the bilge.

The reason for steaming white oak or other wood for bending is to raise the temperature, not increase the moisture content. The wood is not steamed long enough to make a major difference in moisture content. I've never heard of anyone soaking air-dried white oak before steam bending it, but that's not so say it's never done.

[PAR]

I'd have to agree about the WoodenBoat forum. It was once a good place, but is now dominated but a few self appointed experts, who aren't. Don't get me wrong there are several very good and skilled people that hover over there, but they are often shouted down by the "bilge rats", making for an uncomfortable and unreliable place.

About steaming white oak, yes, it does have additional benefits, one major thing is it kills mold and rot spores, so the wood isn't subject to these issues after installation. Sap isn't a real issue, though removing some of the tannins is, which steaming also does nicely. Yes, you do want quarter sawn and vertical grain material for steamed planking, because (as you've guessed) it's more dimensionally stable. Of course, it's also steamed to prevent "edge set" in the planking, which can cause huge issues later in the life of the boat. Generally, you want to planks to "like" living in the bent position, so they don't twist up fasteners, attempt to straighten out frames, flatten decks, etc. Steaming weakens (makes them pliable) the cellular walls of the wood structure so they can stretch and compress without catastrophic failures. When the wood fibers dry (which occurs quickly) the cellular walls remain fixed and are "memory locked" in this new configuration.

No, planking stock that will be steamed is best used when green, not seasoned. The cellular structure is still quite pliable after a tree is felled and this makes steaming faster and easier (moisture content and still pliable walls). Yes, it is quite common to soak thicker stock prior to steaming. It's a moisture content thing and again makes successful bending have a higher percentage, without breakage.

There are a lot of other considerations in steam bending as well. I could probably write a book on the subject. Stock selection, type of grain, type of bend, supporting the outside of the curve during the bend, supper heating the wood, etc., etc., etc.

Was this more of what you had in mind?

[jnjwilson]

Thanks Par, thats the kind of info i'm looking for.If steaming removes some of the tanins is it more iron friendly or does it not make much difference.Also as its put on the boat is there less shrinkage with steamed plank over well dried stock. thank again jnjwilson

[PAR]

The "whites" will always have a bit of trouble with iron fastenings. The acidic nature of it's internal chemical makeup will cause issues. If you can "bond" the fasteners, you'll avoid much of this difficulty, but any "tight" fasteners with direct unprotected wood to fastener contact, will cause a problem if steel.

If that was you Dan, then thanks . . .

[Boston]

not I
but I'm sure you earned em

[PAR]

Okay, well thanks to who ever DL is . . .

[BATAAN]

Is Burnham trunneling the planks or spiking? Essex vessels of old were usually trunneled, which removes the problems iron spikes have with the tannins.
In California we used to steam fir planks when doing repairs to fish boats and tugs. Often it was what made the job possible. Never seemed to make any difference in the fit and most repair planks are shutters. Burnham is planking a new boat so only one shutter so even if the steam did change the plank size, he's only fitting one edge at a time so it would make no difference.
Oak in general moves more than some other woods so is not much used for planking these days. In this instance I believe the Pinky is supposed to be as authentic as possible.
Don Arques advised me once to put 'crankcase drips' (waste lube oil) on anything that went in the steam box, so that is what was done pre-WW2 in some yards.