Bending characteristics of Cherry

[Michael Merrill]

Hello all,

I came up with a project idea some time ago that has a piece of the project that needs to be a laminated bent piece, the piece is a small 3/4 wide piece about 25" long with one end turned up like a water ski but at a higher angle, I would estiamte the angle to be 45-50 degrees and a bend radius of about 5 inches.

I built a MDF mold and built a prototype using maple, resawing the strips to a thickness of about 1/16 or slightly thinner. Making this bend with the maple was fine.

Then I anted to make the same thing from Cherry and went through the same process but bad results, it almost always wants to split at the radius, I even tried a bit of hot pipe bending to get them close then use the form and still no luck. Is Cherry not a good selection for bending????

[Quinn McCarthy]

Mike,

A dry fit trail is the key to success there. If it worked with maple it should work with cherry if all of the facttors stay the same. When I have done bent laminaation I usually use West sustem epoxy. Mainly because I was building boat parts but it worked great and there was no spring back after glue up. Once you have the thin cherry stock sawn I would test clamp again. Sometimes I just use hand pressure when I check the bend. Sometimes don't need clamps for the trial.

I hope that helps you out.

Quinn

[David DeCristoforo]

Is your mold one piece or two? A two piece mold will offer much better results. Also, cherry is a great wood for steam bending.

[bob hertle]

Watch out for grain runout--you want the straightest grained stuff you can find!

Bob

[Glen Butler]

I have only had decent not great results while using steam bending on thin strips. They were 1/8" strips in a 4.5" radius. Some pieces bent nicely while others just snapped. I don't know what made the different, heartwood, sap wood, or the cut, i.e. quartersawn, flatsawn. But some pieces just would not bend and others bend beautifully.

[David DeCristoforo]

"...some pieces just would not bend and others bend beautifully..."

Nature of the beast. Bending wood is a crap shoot at best...

[Michael Merrill]

The mold is two piece, built from a sandwich of 4X3/4 MDF and then draw out the inner and outer dimensions of the shape. I do think my form needs a little "tweaking" to get good pressure in the corner of the radius but it should do the trick.

Also good to hear that bending can vary piece to piece as that is what I experienced with the cherry but most did not cooperate. I think I'll just have to try again, not ready to go full out into the steam box thing. Maybe one option before that is just to soak the strips through very well and then put into the form wet and let dry without glue, then if that works follow-up with the glue.

[Paul Atkins]

Steam box is not that complicated. I bent some 1 1/4" thick cherry for legs and it was fine. Just have to get the steam to heat the whole piece and work fast once it comes out.

[David DeCristoforo]

The idea with steam is to get the wood hot and wet. It's the moist heat that does the trick. Soaking will not do the same thing. Also, a 5" radius is a pretty tight bend with any wood. Seems like a sixteenth should be thin enough to bend without too much problem though. You may just need to select some very straight grained pieces. Look at the edge. If the grain runs off the edge at an angle of more than a few degrees, keep looking...

[Bob Abbott]

For bending, you get better results if the material is flat sawn. Anything not flat sawn is problematic, and anything that is closer to quarter sawn will snap easily. I agree that 1/16" should be thin enough for your radius.

[Russ Hauser]

These Shaker Boxes are made of cherry and were soaked in boiling water. The tighest bend on the smallest box is approximately a 1 1/4 inch radius. The cherry is .070 thick. The wood in these boxes is quater sawn.

I've made, and sold, hundreds of these boxes in various sizes in cherry, maple and walnut. Maple is the easiest to bend, (hardly any breakage), cherry will have a few breaks and walnut breaks about half the time.

Russ Hauser
Tavares, FL

[Michael Merrill]

OK, all great ideas. As for the cutting of the strips I think I did use Flat Sawn, I started with a standard what I think was plain sawn stock, then ripped off a piece about 3/4", then placed that cut edge down and cut strips through the band saw.

So I think my grain is correct, I think looking at most the comments is that I've not got the wood nearly wet enough, even before the hot pipe I needed it soaked more. I also agree that my maple prototype just seemed to take to the bending process easily.

[george wilson]

I made several guitars from cherry years ago,and bent the soaked wood around a hot pipe with a propane torch in it. It bends well.

[Glen Butler]

I steam box can be made fairly cheap. Not including the wood, which I figure you probably have something laying around, Lowe's carries a $55 wall paper steamer. Just cut the hose and stick in a 3/8 hose barb with 3/8 NPT thread. Done. Steamer for $60.

[Michael Merrill]

The more information that comes in, the more I think my problem is moisture! I'm using standard kiln dried stock from my supplier and at mos I was soaking it 20 minutes or so. I figure with these extra thin pieces of stock that even short of fully steaming that just soaking in piping hot water would be more helpful and extend the soak time.

Overall it looks like the verdict is in, Cherry is fine to bend, it's the technique!!!!