[bobhuerbsch]

I'm trying to strengthen the perimeter of paddles which I build with Manilkara bidentata a hardwood known as Bullet wood in English. This wood is extremely heavy so I only want to use it on the perimeter of the blades. To do this I need to steam bend it. Is there anyone out there who is familiar with steam bending "Nispero" ( the above mentioned wood)?

 

[jw2170]

Welcome to the router forum.

Thank you for joining us, Bob.

I have not seen a lot of comment on steam bending, but some one may have experience they are ready to pass on.

 

[wbh1963]

Hello Bob,

Welcome to The Router Forums!

I haven't personally done any steam bending, though I have seen the topic discussed here in the Forums.

 

[notLefty]

i just did a search on Youtube and got this..

steam bending wood - YouTube

i used to make native hand drums, i just split oak boards on a saw and made a steamer out of a piece of new insulated stove pipe in the kitchen routed the steam from a large stew pot with tubing i made with HD aluminum foil. it looks like PVC works too. i took it out and clamped it to a mold real quick.. i had no idea what i was doing, i was way up in the Olympic Peninsula deep woods, way before computers and youtube.

i got the raw hide for the drums off of fresh road killed deer, an a lot of very good dinners too. i did, however lose a few girl friends pulling over to skin out a dear and butcher off the hind quarters.

you need to be REALLY CAREFUL WITH STEAM, THERE ARE NO MINOR STEAM BURNS..

the microwave system looked like a reasonable method for small stuff.

here are some books
Amazon.com: steam bending wood

 

[OPG3]

Check with jlord - he's made reference to steam bending on past posts.

 

[geoff_s]

I'm not familiar with the timber you mention but I have been involved with steaming timber for boat ribs.
The steamer we use is about as basic as you can get, just a large diameter steel pipe with one end in a fire. Add water and timber to taste! (dog is optional)

Steaming time will vary depending on timber and size of piece to steam. We mostly do softwoods so about 1 hours per inch of thickness.
The trick is to get it out of the steam and bent as quickly as possible.

 

[steve l]

Hello Bob, I am new to the forum as well. In fact this is my first reply or post of any kind. I have not steamed Manikara bidentata. I have steam bent allot of wood while making selfbows. (long bows and recurve bows made of one piece of wood. No laminations or fiberglass) I used allot of Osage Orange. One of the densest woods in North America. Steaming and bending wood is not very hard if I can do it. Your set-up is limited only by your imagination. I like to keep things simple. I used a hot plate, cheap coffee pot with a four inch opening, four inch galvanized duct pipe. I took one end of a tee jointed galvanized pipe and place it into the coffee pot. I then attached additional pipe to both sides of the tee joint keeping it more or less symmetrical until it’s longer that the piece of wood being steamed. I also found one hour per inch to be about right. I used tin foil to help seal the joint around the coffee pot opening and at both ends of the pipe. Small holes in the tin foil at the ends of the pipes helped direct the steam. Tilt the pipes up so the water runs back in into the coffee pot and to help the steam flow up the pipes. You will need a jig to clamp your wood to. The jig needs to bend the wood further than you would like the finished piece to be. You will loose a little set when you unclamp. You may want to use gloves when removing the wood from the steam. It will be hot. The faster you can clamp it to our jig the better. The wood will cool fast. My goal was 30 seconds. Some people will use a heat gun to keep the wood to temp if clamping some complex shape. It is best if you can let the wood dry before unclamping. It will keep its shape better. You will find greater success (less breakage) using straight grain wood that is cut following the woods grain. It’s better yet if you can use splits from a log then reducing the size of the wood following the grain. I know this is not always practical. Most pieces that break are from wood that is not hot enough or from grain being violated. I hope this helps.

 

[bobj3]

Hi

I use the Hotsy steam cleaner for bending jobs,(see the one below it's like the one I use)

Quick and easy to bend stock.

==

 

[bobhuerbsch]

Steve, thank you for a detailed answer. Your set up seems easy enough to build and very practical. My son tried bending some of this wood with poor results using a microwave method he found on the internet. I believe one of the reasons he was not successful was the wood he tried to bend was dry. Do you know if the wood needs to be recently cut (wet) and what difference the dry - wet wood has on the success of bending? thanks again bob PS/ Janka hardness of Nispero is 3200

 

[steve l]

Bob, I have never tried to steam a fresh cut piece of wood but my experience is that the drier the wood is when removing from the jig the better it keeps it's shape. I don't think a wet fresh cut piece of wood will keep it's shape very well. I know there are methods of bending wood with heat without steam but I'm sorry to say I have no experience with those methods. In general most bends fail for two reasons. The wood was not hot enough or the grain was violated to much where the bend was taking place. What are the dimensions of the wood you are trying to bend? How hard of a bend are you making?

 

[bobhuerbsch]

The new paddle blade will look somewhat like an inverted parabola more or less 18 inches in height with a flat portion on the bottom. The sharpest bend will have a diameter of approximately 4 inches. This 4 inch bend is at each corner of the blade. The piece of bullet wood would be about 1/2 inch X 1/2 inch X 20 inches. At this time we are not building any paddles so I can't get into too much detail. When we start building some around mid July I'll build a steamer similar to your description and get back to you with some pictures / results. I'm ordering a steam bending book from Amazon tonight so hopefully before we try bending I'll have some more information on this method of woodworking. Our paddles have been very successful in an Ocean to Ocean canoe (cayuco) race which starts in the Atlantic and ends in the Pacific Ocean. That's only 46 miles here where I live next to the Panama Canal. If I can successfully line the perimeter of the blade I believe they'll do even better. thanks again bob

 

[steve l]

Hi Bob, that race sounds fun. When I was younger I did a fair amount of canoeing. The bend you are attempting should be doable. You are making a good amount of bend. We talk about one hour per inch but with wood as dense as you are working with I would not be afraid of steaming it for a hour per half inch. But I would be careful of the grain at the bend. I look forward to hearing from you in July.