Stem bending hint.

[Guest]

Hello All,

I am new to this forum so if this info has been posted before or elsewhere please forgive me. I did a rather detailed search of the topics and could find nothing simular.

I have just bent the stems for a Hiawatha and have experienced a minor set back; one that could easily have been avoided. I am using Yellow Cedar for the inner and Cherry for the outer. All went fine with the first bending until reaching the sharpest point of the curve where the outter most Cherry strip snapped. (I'm hoping I am not the only one to have had this happen.)

Having spent many years bending wood for Classic guitars I know that often some woods need support on the outside of the bend. Unfortunately, this time I chose to not follow my experience. "Don't take the time to do it right the first time you certainly take the time to do it right the second time!"

So, a solution is to include another strip of scrap wood to the outside edge of the bundle being bent. It only has to be the same width as your pieces and about half the thickness works fine. Any easily and smoothly bendable wood will work but I find Yellow cedar or poplar the best. I used a couple scraps from the Yellow cedar inner stem material. There is an added bonus in that you have a built in clamping pad. For those of us who "can't resist reefing down on the clamps,...".

The supported second stem and the re-done first stem bent perfectly.

If, like my piece of Cherry, there is some runout to the grain in likely problematic areas, it is something to think about.

Thanks for reading this far and I hope no-one has to hear that unmistakeable sound....

Happy building.
Scot

[Dean in Eureka, CA]

"If you don't take the time to do it right the first time you certainly take the time to do it right the second time!" .

Well... being a Norwegian...I made my stems three times. :roll: My first set came out OK, but I did get a few "Clamping-Dimples" and then realized that I needed to use a different wood for my inner stems to better support my rudder gudgeons. (Willits Bros. recreation)
The second set was fine, except that I "cleaned" them up just a bit too good because they ended up being only 11/16" wide. The third set was to my liking.
Since I had so many "extra" stems lying around, I ripped down a few of the outer stems to make marking templates for my centerline and 1/8" leading edge marks on my inner stems. This may sound like a lot of trouble to go through to make a set of marking templates, but they worked very well and I had accurate marks layed out in a matter of seconds. The extra steam bending attempts boosted my confidence with the proccess, as I had only bent a banjo head many years prior.

There is an added bonus in that you have a built in clamping pad.

The thought of the extra outer strip being a support strip never even occured to me. I am one of those "clamp-reefers" myself and having that extra strip as a barrier and having gone through the proccess three times gave me the ability to discover the "right" amount of clamping pressure to use as not to end up with a starved joint when epoxying my stems together.

[Steve Lansdowne]

I recently read, I believe in a tool catalog, about a mental "tape" that could be bent around the outisde lamination of wood being bent and then secured, in order to prevent tear out. This sounds similar to what you did using wood.

[Glen Smith]

Yes, it is best to use one extra sacrificial strip to absorb the stress of the bend. It will also act as one large clamp pad to avoid leaving marks on the wood.

[Guest]

Hello All,

"Don't take the time to do it right the first time you certainly take the time to do it right the second time!"

Happy building.
Scot

This is a good idea! I'm gonna try and build a real canoe soon. In our shop we have a modification of your saying. It's aimed at all our employees because the lack of accountabiblity in some of us makes it look like we're shooting each other in the foot. It goes "If you don't have the time to do it right the first time, when will you have the time?"

[Doug]

Lee Valley has a lot of Steam Bending information & tools.

This is the best deal, though.
http://www.leevalley.com/wood/page.asp? ... 5866,45867

Doug

[Danny Turner]

I used your suggestion of using an extra strip and it worked well.All the strips survived the experience ant the extra outside strip absorbed the pressure and marks from the clamps. I can be a wee bit heavy handed at times.
Danny

[Danny Turner]

I used this method of bending without steaming. It worked very well. Unfortunately the outer stems were left for quite a while with cord attached to G clamps at either end to maintain curvature. When I removed the clamps I put the stems in the back of my car under the rear window. The sun was very strong, the epoxy probably weak but the two combined to bust the stem laminates apart.
I have re-epoxied the outer stems and they are now attached and awaiting the final touchup.
But that is a very good tip and I will always use it.