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Sheet Metal Brake - recommendations

I've got a slow build with several user made parts on the plans from what I've seen so far. Right now I'm building the wings and there are two doublers on the rear spar that are a few inches wide and a few more inches long that I need to make.

I found the Rainbow Aviation site where they have a lot of 3D printed jigs to make perfect bend radii on the Harbor Freight 3-in-1 30" brake.

What size is most recommended? I've got access to a 60" sheer and brake through the Commemorative Air Force about 45 minutes away. But I'd really like to get something for the shop to make the bulk of the parts.

Is a 24" brake sufficient? I think I just found a Kaka W-2416Z nearby for a decent price. The Shop Fox 24" is another.

Too much weight is my initial hurdle followed by a place to store it. I could be convinced to spend more on a quality tool as long as we're not getting in to the $4K territory of the production-ready machines.

What's the best way to find one used?
 
Take a look at Swag Offroad's 20 ton finger brake kit for a hydraulic press. They have a selection of dies available and I believe that it will take standard press brake die sections. It probably takes all of 30 seconds to put in the press and be ready to go. One less "big" tool to deal with, unless one is going to do lots of sheet metal work over the next few years.

I've never built any of their tool kits, but from what I've read, they have good stuff. For reference, here's a link to the press brake kit page:

https://www.swagoffroad.com/collections/swag-press-brake-kits
 
HF brake

I have the 30" HF brake. It works just fine. I never needed much more than 12" of it.
I was always disappointed there is no bending part with a radius. I may check on those printed ones. Thx
 
the 30'' hf has worked fine for me. i have never needed more than 10'' of it. i bend radii by first determining proper radius and then contouring the proper thickness of bar stock with a bench grinder and belt sander. works perfect.
 
So it seems like 24" would do the trick. I could probably get away with a 12", but then I'd run across that one 14" that would make me wish for the 24".

That Swag looks interesting. I've already got a HF press at the hangar. I'll have to go measure it to see if it's at least 33".

Otherwise, I'm a HF club member, so I'll wait for the 15% off anything coupon unless I can snag this Kaka that is probably already gone at the price they were asking.
 
Wicked long shot, but

Anyone recognize this make? Available pretty cheap but don't want a 100 mile round trip hassle is it's a POS.
 

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I've gotten by for decades' worth of projects using an inexpensive 18-inch "mini" brake similar to this one. The only thing I changed was to radius the nose piece - otherwise it's been completely adequate for the sort of miscellaneous brackets and so forth need to build an RV. Especially if you have occasional access to a "big boy" finger brake, you probably won't need more than this thing 99% of the time:

31RQ7L6vyEL._AC_SY350_.jpg
 
Anyone recognize this make? Available pretty cheap but don't want a 100 mile round trip hassle is it's a POS.


I've got that brake or a clone of it. It works great. Has a lot of adjustments so you can move the bar back to make room for shims to control the bend radius. I've used it for two -6's and my restoration projects. It would be well worth the trip.
 
I've gotten by for decades' worth of projects using an inexpensive 18-inch "mini" brake similar to this one. The only thing I changed was to radius the nose piece - otherwise it's been completely adequate for the sort of miscellaneous brackets and so forth need to build an RV. Especially if you have occasional access to a "big boy" finger brake, you probably won't need more than this thing 99% of the time:

31RQ7L6vyEL._AC_SY350_.jpg

How does that thing work? How do you create bend radiuses on it? I thought it was really just for air-conditioning duct, gutters, and things like that. And you can only bend something in one plane, right? Like a Z, but maybe not a U.

I've got 3D print templates for various thicknesses of 2024 that work on the HF 3-in-1 30". Would it be possible to do something similar with this?
 
How does that thing work? How do you create bend radiuses on it? I thought it was really just for air-conditioning duct, gutters, and things like that. And you can only bend something in one plane, right? Like a Z, but maybe not a U.

It can bend whatever the radius is that I used when:

The only thing I changed was to radius the nose piece

A very simple device, but in my experience adequate for typical RV fabrication.
 
I ended up snagging this Kaka ($750 retail) for $400 from the dealer as a demo. I asked about bend radius and he said the cam that holds the fingers is eccentric so you can move the fingers back and forth. No idea what this means. :) Yet... (Time to learn)
 

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I ended up snagging this Kaka ($750 retail) for $400 from the dealer as a demo. I asked about bend radius and he said the cam that holds the fingers is eccentric so you can move the fingers back and forth. No idea what this means. :) Yet... (Time to learn)

I'm not the guy here but can share the lesson taught to me and since experienced. He's talking setting the distance between the finger radius/bed contact point and the apron bend point/axis. Setting a bigger gap will widen the bend radius. Chances are, the bend radius will not be exactly constant. A machinist might notice but probably no one else unless you making a relatively large radius that way. Enjoy the new toy.
 
I asked about bend radius and he said the cam that holds the fingers is eccentric so you can move the fingers back and forth. No idea what this means. :) Yet... (Time to learn)
You need to move the fingers back the thickness of the material for a zero radius bend, assuming no radius on the fingers. Imagine the hinged portion swinging up on a 90 deg bend. The material has to fit between that and the fingers. If you need a bigger radius than the fingers provide, insert a shim between the material and fingers. Move the fingers back further to accommodate this new thickness.
 
Zephyr: From experience, when you get ready to start bending, make sure you mount that brake on something substantial. A bit over zealous movement of the counterweight and you can flip that thing on it's back.....Been there, done it and got the shirt, but I did it with a 36" bench model.:cool:
 
Brake fingers

Does anyone know where to get a flat chunk of maybe 2"X24x1/2 with a different radius on each edge?
Nothing fancy. Just a chunk of cold rolled steel with a uniform radius on each edge. 1/16, 1/8, 3/16, 1/4. I can clamp it in place.
I don't use the brake much anymore but one finger for most bends would sure come in handy.
I suppose I could buy a piece and have it milled.
 
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You can use scrap rubber sheet on top of your work. Experiment with different material and thickness with scrap until you get the radius you’re looking for.
Bend radius is adjusted by moving the bed back and forth but for soft material like aluminum you need to augment the process if you have the standard sharp fingers.
 
Larry: Up in post #4, I have a link to Mittler Brothers’s individual finger segment. Widths to 6” and numerous radii. Can’t buy the materials and grind the edge for what they get for the segments. I needed a 6” segment with a .128 nose, and I think it was about $25, plus shipping, when I ordered it.
 
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