# Soaking or steaming



## natenaaron (Jun 24, 2013)

I am wanting to try my hand at a small project using bent wood lamination. Something small to see if I like the process, and get a feel for what the uber dry weather here might do to it. I have been watching a few videos and I have seen both techniques.

I have no idea if the wood I have is kiln dried or air dried. When I asked at the lumber store I was told that it "Doesn't make a difference how it was dried." Apparently they don't know either. So, for the benders out there, is soaking or steaming a better way to go? The laminations will be 7/8×1/8 x a length I have not figured out yet. I have walnut, and maple.


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## jdh122 (Sep 8, 2010)

Not sure about the question - if you're doing bent lamination you don't steam or soak the wood but resaw it thin enough to bend, put it on a form and then glue the plys together. Soaking or steaming would probbaly make the glue fail, I'd think. With bent lamination I don't think it'll make any difference how the wood was dried.

If you want to steam thicker pieces, everyone seems to agree that green is best, then air-dried and lastly kiln-dried, but some people have had good success with kiln-dried wood. I've only ever done it with green wood. Both soaking and steaming will work fine - it's the heat not the water that plasticizes the wood.


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## Mahdeew (Jul 24, 2013)

Walnut bends very nicely. I have used three methods and they all work well depending how fast you want to bend the wood; the fastest way is to soak it over night (for thicker pieces, longer time). Get a steel pipe about 3-4" in diameter and 5-7" long. Place the pipe in a vise and place a torch on the other end. Once the pipe gets hot, place the wood over the pipe and apply light pressure to the areas that need bending. You have to make sure to move the strip few inches at the time to make even bend (if that is the goal). Also, be careful the wood doesn't burn. Another method I use, is to soak the wood for a day and then boil it for while and immediately put in around the mold. Steaming after soaking works the same way but it tends to dry the outside of the wood too fast since I don't have a fully enclosed steamer. I have a picture of a walnut candle holder in my projects if interested.


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## Earlextech (Jan 13, 2011)

If you didn't ask for air dried, you got kiln dried.
The walnut will bend better than the maple.
I like the combination of steam bending with bent lamination. It allows you to use thicker pieces. Steam all the boards at once. Clamp them on your form until they dry. Then do the glue up and put them back on the form. I find this to be the most rock solid way of bending wood. No springback at all.


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## bigblockyeti (Sep 9, 2013)

I haven't tried steam, but from what I understand it will allow you to bend rather thick stock that would otherwise prove fairly rigid when dry. Soaking makes a mess and in my opinion wouldn't be worth the effort if what you're creating is going to be laminated anyway. Dry bending requires significant force depending on the thickness and species of stock you're working with, but will allow you to use your glue of choice, has minimal spring back if you have several laminations in your piece and has tremendous strength once everything is completely dry. The wood doesn't require as much surface prep after laminating as any method that introduces moisture into the wood as the grain could be significantly raised after being soaked.


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## jdh122 (Sep 8, 2010)

Interesting, Earlextech - guess I was wrong and you can combine lamination and steam bending. This would allow Nate to start with pieces thicker than 1/8th of an inch. And by steam-bending then drying the moisture won't interfere with the glue.


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## basswood (Dec 18, 2013)

Thin strips may bend without soaking or steaming, if the radius is large enough.

If you can't get thin, dry stock to bend tight enough for your purposes, then try soaking in the hottest water you can get. Some fabric softener can help with bending too.

I only steam when none of the above will work. I use a wallpaper steamer hooked up to a 4" diameter piece of PVC pipe with my stock inside. I drilled a few holes in the cap at the far end of the pipe so the steam flows the length of the wood.

Use the straightest grained wood you can find.

All this said, sometimes we over think these things, the last time I needed to bend wood, I used a dirty

wheelbarrow full of water from the garden hose and a large rock. Ha!


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## natenaaron (Jun 24, 2013)

These are going to have some serious bends. I guess I should have pointed out that this was to prebend the pieces not glue at the same time.

Earlextech, I would have gotten the same response no matter what I asked. These guys are construction people. Very nice and helpful when it comes to construction needs. Kind of lost in the non construction grade lumber department.


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## Mahdeew (Jul 24, 2013)

Looks good basswood.


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## basswood (Dec 18, 2013)

Natenaaron,

Here is another bending project that I used steam on. I was just having fun with the wheelbarrow example:


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## Mahdeew (Jul 24, 2013)

Looks better.


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## theoldfart (Sep 9, 2011)

I used a fish poacher to steam 3/8" white oak for a set of children's chairs. It worked quite well. If you interested I can post pics tonight.


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## natenaaron (Jun 24, 2013)

Yes I would be interested. For the sake of this being the first project I think the soaking method will be the best idea. No use going to a lot of expense when it is not necessary.


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## theoldfart (Sep 9, 2011)

Nate, I steamed white oak for the backsplats using a fish poacher. I did not submerge the wood rather put it on a rack (I did use the cover):









I made a pattern and clamped each piece till it cooled down. I also rigged up clamps to continue to hold the pieces overnight


















Here they are









And the chairs


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## wormil (Nov 19, 2011)

I didn't see this answered but it is heat, not water, that makes the wood flexible. Steam just helps carry and hold the heat inside the wood, the moisture prevents darkening. You can bend dried wood without steam but you can't bend without heat.


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## FatherHooligan (Mar 27, 2008)

My understanding is that it is the softening of the lignin, a 'connective tissue' of wood that first allows it to bend the wood and the re-solidifying of the lignin that 'freezes' the newly bent wood. Softening with just water works, but my understanding is that heat and moisture provide the most predictable and consistent and timely bending. Boat builders bend surprisingly massive pieces of wood with varios bending methods. During the assembly of my scow I was surprised that I could cold bend 1 1/4 inch square kiln dried Douglas Fir chines, over a large radius mind


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## WhoMe (Jul 9, 2009)

The Feb 2014 Fine Woodworking Mag has a article on steam bending. A fair amount of good basic info. 
Worth a read.


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## basswood (Dec 18, 2013)

Another advantage of steaming (or dry heat), that has not been mentioned is that it expands the gases in the structure of the wood. This helps with the glue up (if you work quickly), because as those gases cool a vacuum is created on a microscopic scale within the wood. Basically, as the wood cools the laminations suck themselves together, boosting whatever clamping force you apply.


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## runswithscissors (Nov 8, 2012)

As Rick M. and others pointed out, it is heat, not moisture, that enables bending. I have bent oak that had sat in the shop loft for 50 years or more.









The significance of the bend (a function of thickness, amount of bend, and species of wood) is what determines what you can get away with. White oak (but also red oak), elm, and black locust are all excellent bending woods. And there are others as well.

Dry heat works very well. It's advantages are that it doesn't raise the grain, and as soon as it's cooled, which happens very quickly, it's ready for gluing. A lamination made up of pre-bent pieces is very strong and there will be negligible spring back. Also, dry heat doesn't discolor the wood. I disagree with Rick on that point, as water can turn white oak black, rather than preventing discoloration.

A hot air gun works very well. You just have to be careful about scorching the wood. And if the bend is at all significant (see above), you must use a bending strap, well secured at both ends, to have a successful bend. Any flexible, springy steel strap works well. I use strapping salvaged from the lumber yard dumpster.

The bent oak in the photo took about 10 minutes from start to finish. The bending strap is lying across it. I originally did this sample just to answer an LJ query about achieving a 45 deg. bend for edging on a three cornered table (two 45s and a 90).


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## wormil (Nov 19, 2011)

I was thinking of luthiers who bend thin pieces of wood against a hot pipe. Maybe burning or darkening isn't really a concern, I just read in a guitar making book that you should mist with water to guard against it.


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## Flocktothewall (Jan 16, 2011)

I agree with Earlex on steaming and allowing to dry in form. I've made a few fishing nets with bent lamination, and for me the first time I tried to steam it and glue while it was pliable was a nightmare. The second net I made, I steamed it, and put it in the form for 24hrs and glued and then form again.










The glue is important as well, I used resin glue. So far I've bent curly maple, mahogany, oak. claro walnut and straight walnut. Air dried lumber is much better, as is cutting with the grain of the wood.










I wasn't keen on soaking as I thought the wood would absorb more water than steam. With steam I went on the rule of thumb 15 min for ever 1/4" of thickness.










My wife has one of those shark steam cleaners, I simply got a PVC pipe and put a plug on one end, drilled a hole for the steamer hose, and on the other end I draped a rag over it NOT PRETTY but worked.

I also propped up the pvc pipe on the capped end so any condensation would drip out of the open end (as you can see with duct tape). I drilled holes in the PVC pipe to rest the strips of wood.

For larger pieces I assume a box of plywood held with some screws would suffice…


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## natenaaron (Jun 24, 2013)

Thanks Luke. A landing net is the exact project I had mind.


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## iminmyshop (Dec 9, 2012)

The walnut cut thin will bend nicely. The maple will be a much bigger challenge. You can certainly bend both with steaming or lamination or a combination of the two as others have already noted above. A combination of both is especially helpful for the maple which is not inclined to bend nearly as easily.

Do NOT steam the walnut and maple together as some of the walnut color is likely to bleed into the maple if they are touching. Immediately put the steamed laminations into a form and clamp letting them fully dry for at least a day or two. Prebending with steam will make the glue-up for the laminations much easier and less stressful since the pieces are already mostly already where you want them. A lamination will make the finished product much stronger than a steam bent only thicker piece of wood. Good luck and have fun.


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## natenaaron (Jun 24, 2013)

Thanks for the pointers iminmyshop. I learned the hard way about walnut staining. I still have a big stain on the concrete after getting caught planing when a rain storm hit. I saved the wood but the pile of shavings stayed on the ground. That was 6 months ago and my wife still points it out.


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## basswood (Dec 18, 2013)

Luke, That is very similar to the setup I use for steaming (though that is actually ABS pipe not PVC-would work essentially the same).

If stream is not available (because someone does not want to rent or buy a steamer), hot water can work fine for some projects. Wet wood favors poly glues, like Gorilla glue, that depend on moisture to cure. This is a closeup of an arched-top pocket door that I built where hot water was just the ticket. It depends on the radius, species and thickness of the wood which technique I use.


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## basswood (Dec 18, 2013)




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