iDRY Vacuum Kilns

Sponsors:

Steam bending

Started by addysdaddy, December 08, 2015, 07:37:48 AM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

addysdaddy

Morning Folks. Looking at trying to do some steam bending of Birch and Maple saplings for the backs of some rustic chairs and benches. I have plans for a basic wood steaming box but would appreciate advice on how long to steam 1-2 inch diameter saplings and do you steam and bend right after harvesting them or do you dry first to cure and then go to the bending process. Bark on or off... any ideas appreciated..
Trying to think of something Cool to say kinda defeats the purpose.
LT10
Kioti with winch.
Husqvarna fan

Dodgy Loner

I've done some steam-bending, so hopefully I can help point you in the right direction. A 1" sapling would probably take only 30-45 minutes to steam. A 2" diameter sapling would take over an hour, maybe an 1 1/2 hours. This varies considerably depending on how powerful your steam rig is and how small your box is and how tight of a bend you're going for.

Ideally, your box is just big enough to hold the parts that you're steaming. Too big of a box allows the heat to dissipate. The first time I did steam-bending, I used a 12" x 12" x 48" plywood box. It worked OK, but I got more springback than I was hoping for. Now I have some 4" PVC pipe that I use. Much better for the small chair parts that I'm steaming.

You can proceed with the steaming while the wood is still green, or you can wait for them to dry a bit. They definitely don't have to be air-dry before you steam them. I would definitely remove the bark from the pieces. The parts would probably still bend fine with bark on, but they would take much longer to dry out. Your parts will not hold the bend until they are dry, so leaving the bark on would be a very long time on the drying racks. If that's OK with you, then bark-on should be fine (I would assume - never tried it myself).

Good luck and be sure to post pictures :)
"There is hardly anything in the world that some man cannot make a little worse and sell a little cheaper, and the people who consider price only are this man's lawful prey." -John Ruskin

Any idiot can write a woodworking blog. Here's mine.

yukon cornelius

dodgy loner, I have been wondering if pvc would work. I have a 10' long 6" pvc capped on one end and a screw cap on the other I had on the back burner of ideas for a steam chamber. Addysdaddy, I hope your project goes well.

I had also wondered if the sapplings would just bend green. Within reason of course.
It seems I am a coarse thread bolt in a world of fine threaded nuts!

Making a living with a manual mill can be done!

Dodgy Loner

I have heard tales of schedule 40 PVC melting with a powerful steam rig. Schedule 80 is recommended, but I couldn't find it at my local hardware store.

I do have my pipe attached to a 2x4 for support in case the plastic softens - should keep it from sagging.

I know you can cold-bend green hickory, but I've heard that other woods don't hold the bend as well as hickory will.
"There is hardly anything in the world that some man cannot make a little worse and sell a little cheaper, and the people who consider price only are this man's lawful prey." -John Ruskin

Any idiot can write a woodworking blog. Here's mine.

azmtnman

Quote from: Dodgy Loner on December 08, 2015, 09:34:37 AM
I have heard tales of schedule 40 PVC melting with a powerful steam rig. Schedule 80 is recommended, but I couldn't find it at my local hardware store.
CPVC will take hotter temps. It may be hard to find in big enough sizes.
You could also use round metal ductwork or single-walled flue pipe. That is inexpensive and readily available. It is also easily insulated if need be.
1983 LT 30, 1990 Kubota L3750DT, 2006 Polaris 500 EFI, '03 Dodge D2500 Cummins powered 4X4 long-bed crew cab, 1961 Ford backhoe, Stihl MS250, MS311 and MS661--I cut trees for my boss who was a Jewish carpenter!

mesquite buckeye

Junk water heaters can be adapted for this and are very cheap. ;D
Manage 80 acre tree farm in central Missouri and Mesquite timber and about a gozillion saguaros in Arizona.

isawlogs

 I have steamed bent a few things, a tobogan for one. Make a wooden box the size you need to fit the peices you're going to bend. If its something you will do more of, keep the box, if not take it apart and make a new one the next time you have something to steam.

   


 

My steamer, an old stainless milk can with lid, piping to the wooden box that changes in size for what I need, this one was for the tobogan.
A man does not always grow wise as he grows old , but he always grows old as he grows wise .

   Marcel

Dodgy Loner

Quote from: mesquite buckeye on December 08, 2015, 11:21:01 AM
Junk water heaters can be adapted for this and are very cheap. ;D

That's a pretty good idea. My steam source is a $6 tea kettle and a $10 hot plate from Wal-Mart. Also very cheap, but easy to run out of water if you have a long steaming session. Luckily I don't bend anything much over 1" in diameter so the tea kettle will hold enough to last an hour, no problem.
"There is hardly anything in the world that some man cannot make a little worse and sell a little cheaper, and the people who consider price only are this man's lawful prey." -John Ruskin

Any idiot can write a woodworking blog. Here's mine.

mesquite buckeye

The ones I have seen get the top cut off w a torch and sit at an angle w water in the bottom with fire applied there. If it was rusted through just flip it over and cut out the bottom instead. Weld on a strap of steel for a lip and a handle for picking up that lid and you are good to go. :) :)
Manage 80 acre tree farm in central Missouri and Mesquite timber and about a gozillion saguaros in Arizona.

Peter Drouin

Quote from: isawlogs on December 08, 2015, 12:06:59 PM
I have steamed bent a few things, a tobogan for one. Make a wooden box the size you need to fit the peices you're going to bend. If its something you will do more of, keep the box, if not take it apart and make a new one the next time you have something to steam.

   


 

My steamer, an old stainless milk can with lid, piping to the wooden box that changes in size for what I need, this one was for the tobogan.



What kind of wood do you use for the toboggan?
A&P saw Mill LLC.
45' of Wood Mizer, cutting since 1987.
License NH softwood grader.

isawlogs

 I used white ash that I resawed to 5/16" I had some of the boards break at the bend while bending, but I knew those where questionable to beging with best have quarter sawn boards to bend tem to make a sled.

     


 

  This is the mold I made ....



 

  This is the tobogan ready for the test ride !!!

A man does not always grow wise as he grows old , but he always grows old as he grows wise .

   Marcel

yukon cornelius

Quote from: isawlogs on December 09, 2015, 08:39:30 AM
I used white ash that I resawed to 5/16" I had some of the boards break at the bend while bending, but I knew those where questionable to beging with best have quarter sawn boards to bend tem to make a sled.

     


 

  This is the mold I made ....



 

  This is the tobogan ready for the test ride !!!

That is awesome!

Did you laminate them? and if you did how thick did you end with? my oldest son wants to make one.

hope im not hijackin this....if you steam them and then bend them do you have to kiln dry them or air dry them and how long would they have to be in the jig until you knew they were ready to remove?

what a great topic, thanks
It seems I am a coarse thread bolt in a world of fine threaded nuts!

Making a living with a manual mill can be done!

OffGrid973

I love this topic and idea.  If any more details on the drying times and details are available, and pics I would also love to see them.

great job !!!
Your Fellow Woodworker,
- Off Grid

isawlogs

I made a thread while making the tobogan a few years ago.....

It should be here 

https://forestryforum.com/board/index.php/topic,64087.msg954436.html#msg954436

If after looking at that thread you have any questions,.. ask away  :)   :P


A man does not always grow wise as he grows old , but he always grows old as he grows wise .

   Marcel

Dodgy Loner

Quote from: yukon cornelius on December 09, 2015, 12:35:44 PM
hope im not hijackin this....if you steam them and then bend them do you have to kiln dry them or air dry them and how long would they have to be in the jig until you knew they were ready to remove?

what a great topic, thanks

yukon, you needn't kiln dry steam-bent parts. They only need to be air-dried. The thicker the part is, the longer they will have to stay in the form.  I have made many steam-bent back slats for ladderback chairs, they're 1/4" thick and they stay in the bending forms for a week.

If your material is thicker, it may take 2 weeks or a month to fully dry. You can certainly hasten the process with a small kiln. My kiln is just an OSB box, 18" x 24" x 36". The heating element is a couple of 100-w light bulbs. It gets to maybe 120-130*F. Crack the top a bit for circulation. I just dry chair parts in it, so it doesn't have to be big. Smaller the better.
"There is hardly anything in the world that some man cannot make a little worse and sell a little cheaper, and the people who consider price only are this man's lawful prey." -John Ruskin

Any idiot can write a woodworking blog. Here's mine.

isawlogs

Quote from: yukon cornelius on December 09, 2015, 12:35:44 PM
Quote from: isawlogs on December 09, 2015, 08:39:30 AM

That is awesome!

Did you laminate them? and if you did how thick did you end with? my oldest son wants to make one.

hope im not hijackin this....if you steam them and then bend them do you have to kiln dry them or air dry them and how long would they have to be in the jig until you knew they were ready to remove?

what a great topic, thanks

  I did not laminate them, they where resawed from a board I had that was air drying but far from dry. I first resawed them to 3" wide, then resawed those to 3/8th" X 3" and finished them to 5/16th" I put thall of them in the steam for 4 to 6 hrs and then a day or so in the mold.... I made all the other parts ready to put the tobogan together as it came out of the mold. I was quite happy with how it all went together.
A man does not always grow wise as he grows old , but he always grows old as he grows wise .

   Marcel

addysdaddy

 8) Thanx for the ideas and info... I put a small steam box together last night for a trial run... Learned my first lesson as well... Make sure you put your wire hangers in before you close in the last side of the box...  >:( >:( >:(... They are a bugger to fish through after the box is done... :D :D... Happy for the small hijack as well... that toboggan looks great and looks like a cool project for my retirement...
Trying to think of something Cool to say kinda defeats the purpose.
LT10
Kioti with winch.
Husqvarna fan

isawlogs

 Your steam box not need be sealed shut, mine had the top board closed with four screws, to wich I twirled wire around to keep it shut, had access to inside by untwirling the wire. There was nothing fancy about my settup.. nothing...  :D But it did the job.  :)
A man does not always grow wise as he grows old , but he always grows old as he grows wise .

   Marcel

OffGrid973

Can't believe someone didn't lose their face 1min 50sec in, but this still looks like a must do tabogon project when I learn how to bend properly.  Anything I should not do from this video :)

https://m.youtube.com/watch?v=01iMdq0K8Vg
Your Fellow Woodworker,
- Off Grid

downsouth

Pretty cool vid.
Check out the roofing on his shed. That's using what ya got.

BHC

I have a wooden one i use for canoes, it 10"x10" and 8ft long, i have 6" stove pipe coming into the bottom which goes down to a 5 gallon metal bucket/which has a 6" hole for the stove pipe, i put on a propane boiler like for lobsters. Before i use it i try and soak it a few days to seal up the cracks but it works well. there is a door on the end for the wood entrance and one on the top to add more water, it has dividers in it so i can put 12 canoe ribs and 2 stems. When ribbiing a canoe i add one every time i take one out, till i am done. The stems are 1x1 ash and by the time i get the ribs nailed on it goes around the form pretty easy key is having a good form that holds your wood, if it is not hot enough you can soak rags with hot water and apply to tough spots, to get them to the right shape.
I know some who make snowshoes actually use steel pipe in which the wood sets in the water.
84 C5D Tree Farmer, 78 S8 International, Thompson Band Mill, M14 Foyley Belsaw

Thank You Sponsors!