Bending Wood Question

Hey Friends,

I am bending 1/8th strips of shag bark hickory to make Native American ball sticks. For some reason, the wood I harvested is cracking during the bend unlike any other hickory I've used in the past.

Questions for you pro wood benders:

1) I harvested the wood a little late in the year (May). Would this really make that much difference in bending?

2) Can the place where I harvested hickory make a big difference? I got the wood 75 miles north of me in a state park (with permission).

3) I've been trying to steam bend the wood. I built a steam box using 4" PVC and a steam kettle. It seems to work ok. Using the 1 inch per hour formula, I tried steaming for 10 minutes, no luck. 20 minutes, no luck. 30 minutes, some luck. At what point am I oversteaming the 1/8th inch strips to make them weak? Should I go ahead steam even longer to make hopefully more successful bends?

Thanks much for any help.

S.

Reply to
samson
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Never bent hickory, but I made some laminated chair rails with 1/8" oak; it bent just fine without steaming. Didn't the Native Americans use oak?

Yes, the 1/16" bent easier, but the 1/8" worked.

Reply to
Toller

no

no

15 to 20 minutes is about right, probably 20 minutes is better. You need a full uninterrupted steam source during that time. Work quickly--You have (only!) 20 seconds to bend the wood and get it into the form after removing it from the steam box. Using thick leather gloves, bend the wood gently. Steaming a piece twice doesn't work well. You can remove the wood from the form after it cools. Expect 8% springback.

Reply to
Phisherman

This is not an expert response, so act accordingly!!!

I went through this process recently trying to bend some 28 inch long

5/8" diameter spindles for repair of a rocking chair. My observations:

The maple dowels I first bought for this project didn't ever want to bend!

If the PVC isn't sagging, you aren't getting enough steam/heat.

You need a LOT of WET steam!!!!

So, here's what I did:

Switched to white oak.

Sawed out some 3/4" X 1 inch samples to try before spnending a lot of time on the lathe

I got out my heat gun. I laid the parts to be bent on the laundry tub and dribbled the hottest water I could get from the tap over the part while passing the heat gun blast back and forth over the part. I did this for 3 or 4 minutes. Then the parts bent easily. It also seemed that the extra wettness gave me a couple of minutes of bend time.

It seemed that the wetness helped me a lot, even though I read that it's the heat, not the steam that makes bending work. The literature did say that heat without water dries the wood out too fast.

Pete Stanaitis

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sams> Hey Friends,

Reply to
spaco

I'd try to go for thinner laminations, 1/8", depending on the kind of curves you're going for, may be kind of thick. Try it with 1/16" and see if it helps.

Reply to
Brian Henderson

Phisherman wrote: You can remove the wood from the form after it cools. Expect

I am -simply- curious about this. Where did you get this figure and how do you calculate for it in making a jig? I have a design in mind that will call for a curve terminating in a 90 deg. turn as below:

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Reply to
BillinDetroit

A followup:

1) Question about oak. It's good for bending, yes, but hickory is (usually) quite elastic and dries hard as a rock. So it's good for ballsticks.

2) I reconfigured my steam box using a teapot that is more or less airtight and used a hose clamp so I would lose much steam. (Yes, I have a drip/steam release hole.)

3) I only allowed myself 20 seconds after heating for 20 minutes. The results were excellent. I broke 2 (on a knotty part -- of the four sections of the blank I could cut and bend, these sections were the least knotty) and made 2 very good bends on clean strips with little or no knotty parts.

I really appreciate the input and advice.

S.

Reply to
samson

Bill, I'm jumping in here a little late. Are you doing laminates bendups from thinly cut strips? If so, I can post a few pics of forms I've made for laminated table skirts and laminated rocking chair rocker.

ROY!

Reply to
ROY!

You may have already realized steam bending is more of an art than a science. Recently I bent three different kinds of 1/8" thick wood. The walnut bent easier than oak (surprise!), and the oak bent easier than another (unknown) pinkish-colored wood. I broke about 1 out of

10 pieces when bending, but I say it was more due to operator fault than the steaming process. Selecting long grain wood without knots will give better results.
Reply to
Phisherman

The 8% springback is a guideline. It may be 5%, so you should design your bending jig with the thought that it may require a slight angle adjustment. If the jig is at an 84-degree angle, your wood, after it has cooled in the jig, will springback to abut 90 degrees. Different thickness and wood type make a difference. There are all kinds of steam bending jig designs and you need one where you can easily and quickly put the steamed wood into it and clamped without any fuss. Steam burns hurt--use care and leather gloves.

Reply to
Phisherman

Yes. It will look like 1/2 of a traditional heart shape with a flat to hold a candle / oil lamp. The two halves are to interlink. Just any old wood on the inside plies, something snazzy on the two exterior plies.

Bill

Reply to
BillinDetroit

BillinDetroit I learned alot by reading up about steam bending from this publication.

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try thhis link,
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to group alt.binaries.pictures.woodworking. I posted pics of two curved shelf facings I bent. I'll add it was a challenge. Francis

Reply to
ghost

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