Thread: Steam Bending Jarrah - Noob assist

By the way, heres a quick 3D of what I'm trying to do.

Well... depends on several factors

1) The size of the peices

2) How you intend to do it

Depending on your answers to the two factors will depend on the responses

Cheers
Shane

mmm okay maybe your busy at work... or something... rightio then let me extrapolate a tad make a few assumptions and give you some increadible insights that you can do with as you wish

1) depending on size of the curved bits

1a) let us use 1a as the repository for smaller peices... this assuming that the curved peices will be no longer than say 10in and no wider than say 1/2in

So what you should probably do is cut the Jarrah into strips say 1/8th inch thick and to the length required that takes into account the final curve... this you can work out from your mould... you will be making a mould I assume? this you will need to bend the wood around to get your final shape... so having made your mould from chipboard ply or offcuts laying around and shaped to the curve you desire... and youve now cut your strips however many that will mean (Im not a mathematician)

So now since were working with small thin strips of timber you wont need a steam box (covered later in this extrapolation of utter brilliance) you can simply get some HOT wet t towels... for this I generally nick some from the missus when shes not looking but other blokes have different methods... boil some water in the kettle and pour the boiling water into a bowl... I use a crock pot but thats just cause I dont ever intend making another stew as long as I live... put the t towels into the boiling water then when soaking wet take them out and wrap the strips...

Now leave them wrapped in the boiling t towels until the towels are NEARLY warm and check the wobbliness of the timber if its loose an droops badly QUICKLY put it to the mould (also known as a form) and clamp it there... let it dry... now do another... and another and another until the stack of thin Jarrah strips are all the same shape... note there will be a slight amount of spring back once they are released from the mould but you will make the mould slightly smaller than what is actually needed to compensate for this right?

Okay now that you have the stack... you need to lay some plastic wrap on and around the edge of the mould... I simply nick the missus's glad wrap when shes not looking but others will have other methods... okay now get lay the first peice down on the bench against the mould so it forms to the shape run a bead of glue along the edge that you will be laying the next strip to quickly smear the glue to cover the timber edge to edge quickly lay the next strip against that one do the glue thing again lay the next and so on until you have your final thickness... clamp leave to dry go have a few beers

When you get back it unclamp the curved peice of Jarrah... it will now be one single peice of 1/2in thick jarrah shaped as a curve.

1b) Assuming its a 1/2in x 1/2in thick single peice of Jarrah you intend to curve... you will need to make yourself a small steam bending box to achieve good results... this is a simple box longer by half the length of the longest peice your doing one end fixed closed the other with a flap door... you will drill and fit dowel pegs or rails through from side to side for the 1/2in x 1/2in timber to lay on

You will also need a large kettle or one of those camping stoves with a kettle on the stand thing....

oops be back shortly gotta run!!

Just a small point I discovered while researching steam bending for the curved beams for Artisans Retreat....
Apparently kiln dried timber is not really suitable for steam bending.
The kiln drying process alters the lignin in the cells stopping them from getting all nice & rubbery like you want.
I was told that air dried is the way to go.
Sooooo - I surrendered & devised a different way to make the beams!
http://www.woodworkforums.ubeaut.com...ad.php?t=55810
Good luck
Ozartisan

Hi there,Jarrah does not like to be steam bent.We have tried to do that where I work,to no avail...We now bandsaw the shape and sand it finished.Cheers

Many thanks to Wild Dingo for all the information, I really appreciate it. Thanks also to Ozartisan & tazchris for the feedback, great knowledge to have. Does anyone know of what timbers are best suited to bending?

Dunno if this'll help, as I've never tried bending Jarrah, but...

Mesquite is another wood that doesn't like being bent... so much so that the few times I have seen items incorporating bent pieces I've also heard other people muttering in disbelief about "trained it on the tree" and "cunningly painted grain."

In one of my turning related books, a bloke taks about how he boils it for an hour, then nukes it in a microwave for a couple of 10 second periods, until it starts to "crackle." he then quickly bends it shape by hand, while holding it under cold running water to set the shape.

I've tried this on other woods (that can be steamed) and it works - although I reckon steaming is easier, for all that it takes longer.

Just thought it may be worth trying on a scrap piece...

Howdy again,Tasmanian Blackwood bend well,you will need to put it into water for a day.Tas Myrtle also bend well.If you want to keep the red,burgandy theme of your cabinet.(Myrtle is a dark pink colour)Tas Huon Pine bend well also.I do not know where you would get these timbers from over your way.Cheers

Originally Posted by Spoon Man

Many thanks to Wild Dingo for all the information, I really appreciate it. Thanks also to Ozartisan & tazchris for the feedback, great knowledge to have. Does anyone know of what timbers are best suited to bending?

Rosewoods are very easy to bend.

Here's a little feedback based on my experiences with bending. First off, if it's been kiln dried, wood is next to impossible to steam bend. The heat of the kiln sets the cellulose fibers in the wood. To bend, you want either green or air dried lumber.

Some woods bend better than others. Ash is one I've bent successfully, it's one of the better woods for bending.

Most of the stuff I bend is lamination bending. Cutting 1/8" thick strips and using a form to bend them over, put glue between the strips and bend them all at one time to form your piece. You also may need to have a strap on the outside edge to pull that down to the profile of the form or you may have breakage of the outer strips.

Some woods just resist sucessful bending, just the nature of the beast.

Hope that helps

Paul

Originally Posted by tazchris

Howdy again,Tasmanian Blackwood bend well,you will need to put it into water for a day.Tas Myrtle also bend well.If you want to keep the red,burgandy theme of your cabinet.(Myrtle is a dark pink colour)Tas Huon Pine bend well also.I do not know where you would get these timbers from over your way.Cheers

Thanks tazchris, I actually have some Tasmanian Myrtle, beautiful piece which I may use as an accent piece. I have already built the frame from Jarrah anyway, and used european oak (quarter cut for the panel inlay) I also have some ebony that I thought about using for decorative elements but I don;t want to go overboard with too many colours and timbers.

Great information too Paul, there seems to be bit of a trick to balancing species of timber, processed dried method, length, size for bending wood. What soert of glue should I use on the laminations?

I have attached an image of what I have done to date, I have modified the door pattern and will use the curve on the middle section. The middle section will have a computer built insode the unit for use as a media centre.

Well... there you go The day went form rather bland to totally colorless in a gnats phart... anyway its over now so where were we?

Oh right bending the Jarrah... it can be done you know Just gotta do it propally thats all

So as I was saying before a bunch of things rudely interrupted me...

1b) Assuming its a 1/2in x 1/2in thick single peice of Jarrah you intend to curve... you will need to make yourself a small steam bending box to achieve good results... this is a simple box longer by half the length of the longest peice your doing one end fixed closed the other with a flap door... you will drill and fit dowel pegs or rails through from side to side for the 1/2in x 1/2in timber to lay on

You will also need a large kettle or one of those camping stoves with a kettle on the stand thing....

fill it with H2o and set it to boiling... set your Jarrah peices inside on the rails close the flap (or if your a bit ruff an ready stuff the end with rags it shouldnt be totally sealed!) and let er rip!! boil away... have a few beers again... head back over and standing to one side open the end and drag a peice out with your heavily gloved hands (STEAM BURNS!!) if it droops its done...

Now you better have that mould real close cause this is where you start moving... you gotta get those peices onto the mould and clamped up QUICK SMART so it forms to the shape while HOT bendy

Once done turn of the gas empty the kettle and put that stuff away...

After the timber has dried it will have taken up the shape... again it will have some small spring back but again you will have allowed for that when you made your mould slightly smaller than what is needed

Okay now many will argue that Jarrah wont bend... but think about this for a tick or two most fishing pearling and other work boats in WA prior to say 1960 were built using mostly Jarrah for the frames (bent Jarrah that is)

Other timbers? Ramps has had great success with Sheoak and I know that Karri bends well personally Id think most hardwood timbers will bend... although again some would argue with me but thats cool

AND BY THE WAY Spooner me ol mate... you havent yet told us the measurements!! so how big are the peices are you bending? Unless Im mistaken theyre not that big... so a suggestion would be to give number 1a a go if that doesnt work or you dont like the laminated look try number 1b... make these test peices the same size as the ones you will be using... if it works the first time and you like the result no need to try the second one eh?

ANYWAYS!!!

All the best
Cheers
Shane

oooh and... your welcome

Thanks Wild Dingo, I really appreciate all your input. I have actually tried bending the Jarrah by soaking it in boiling water, these were only small pieces approx. 10mm thick by 500mm long. I had some success and the bend I'm now aiming for in the middel section of the unit will have a very gradual/light bend which I think will be achievable with Jarrah. The length I'll need to bend will be approx. 300mm (still need to work it out exactly). The bend will be secured with the Oak following the same curvature (as I know oak bends well). I'll keep you up to date with the progress of the unit, thanks again to all.

Why not just use a bent lamination, with Techniglue epoxy? It is easy, foolproof, and predictable; you just need to make a former of the shape that you require.

Rocker