Spar bending

[Bradrock]

Is there any reason not to use a hydraulic press brake, rather than a traditional bending brake, provided the bend radii criteria are adhered to?

[X'N]

I used a press break to do mine. Only problem you may run into is depending on the dies you can't bend more than 90*

[DesertBearhawk]

I used a Press Break on mine as well and then I tuned them up on a 8" traditional break.

[John Massaro]

Huh?
Am I missing something here but I was under the impression that you needed a bending brake in the neighborhood of 8' aka 96" to bend the spars or webs as some refer to them?

I would tend to agree that as long as the dimensions and bend radii can be met the method used would be of little if no consequence in this operation.

Dave, I've enjoyed watching your progress on YouTube but could you fill me in on how you "tuned them up on a 8" break (sp)".

What I've been toying with is getting my hands on a particular aluminum siding brake that seems to have the "guts" (rigidity, stiffness, clamping force) to bend the spars without having to build a brake or pay for them to be done.

[DRLPatrol]

John, Please let us know how the siding brake works. I have been thinking about them for when the time comes, but didn't know if they could work. Around here they are in Craigslist all the time. Seems like I could buy one, bend the spars, then sell it.

Doug

[DesertBearhawk]

John, The main and rear spars have angles that are greater than 90 degrees. The press break will only bend to 90, so I took them to a 8' break and used that to bend them the additional amount…hence I tuned them up. I now have that same break in my shop which brings me too:

I seriously doubt the siding break is going to work. As I indicated I have a Bad-@ss, heavy dang duty, in your face 8 foot break in my garage and I am using it to bend my flap and aileron spars and I have found that even with all that it is its still tough to get the bend angle consistant across the span, I don't think there is a chance you are going to get the bends right on a siding break.

YMMV

Dave

[X'N]

I remember reading on the yahoo forum where guys had tried using a siding break but were unable to make it work. There's a thread here that has all sorts of plans for making a break check it out. http://bearhawkforums.com/forum/tool...1-spar-bending

FYI if your building a patrol you'll need a break that can do 105" for the flaps