Sheet metal enclosures... inspire me

Looks like the upper piece on that brake should have some adjustment front to back to adjust the radius a little.

You can sometimes run into problems if it's set up for a tight bend on thin sheet steel, and you put some thick aluminum in, it will try to shear it and you'll have a deep depression in the bottom of your bend and the material will be weaker there. Hard to tell from your photo, but you might have a little of that going on in the lower bend? The upper bend looks fine, might just be a weird shadow I'm seeing on the lower one. Other than that, as long as you like the look of the radius, and you can adjust your cad model to match, you should be good.
 
If you raise up the moving part like you're making a bend, but with no material in the bender, and look at the gap between the clamp bar, and the swinging part, if that gap is much smaller than your material thickness, that's where the pinching would come from. Not sure if that makes any sense...
 
Erik S said:
Looks like the upper piece on that brake should have some adjustment front to back to adjust the radius a little.

You can sometimes run into problems if it's set up for a tight bend on thin sheet steel, and you put some thick aluminum in, it will try to shear it and you'll have a deep depression in the bottom of your bend and the material will be weaker there. Hard to tell from your photo, but you might have a little of that going on in the lower bend? The upper bend looks fine, might just be a weird shadow I'm seeing on the lower one. Other than that, as long as you like the look of the radius, and you can adjust your cad model to match, you should be good.
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Yup this sounds about right. What’s crazy is I caught that and it bothered me. I immediately knew that by adjusting the head back a little bit should relieve that deep indent. If you also look the outside walls where the bends are made the aluminum almost looks”squished”. I’m going to be playing with the adjustments and see if I can eliminate that while keep the correct bend radius for the aluminum.
 
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Erik S said:
If you raise up the moving part like you're making a bend, but with no material in the bender, and look at the gap between the clamp bar, and the swinging part, if that gap is much smaller than your material thickness, that's where the pinching would come from. Not sure if that makes any sense...
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Makes 100 percent sense!
 
Ok comparing to the first bend (smaller piece) I bent that piece and youre right it broke. The one on the right are bends i just made after adjusting. After trying to pull it apart with my hands it did not break. With that said the bend radius is not as tight. A compromise i think i can deal with. Any thoughts on if i should go back a little further with the adjustment? I have maybe a little more than 1mm of play left till it will not let me go back any further.

unnamed (7).jpg


Heres a cleaner bend:

unnamed (8).jpg

Trying to dial it in now:


unnamed (9).jpg


EDIT: So i also noticed the how much pressure im applying "clamp" part of the brake determines how sharp the inside bend will be.

So i found out my bend radius is 1t of my total thickness. Which is .063". I think im right....lol
 
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The fit between the two pieces looks great. Locating the bend lines to result in a tight fit like that is the trickiest part!
 
temol said:
For this type of the enclosure it's probably better to bend bottom piece first. Then cut the upper element to exact width. Much easier than bending to exact width.
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Dude tell me about it. Thats exactly what im going to do first next time. Getting that bottom plate to fit was a nightmare. This small tip is going to save me in the future!

Erik S said:
The fit between the two pieces looks great. Locating the bend lines to result in a tight fit like that is the trickiest part!
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Man it is! Thats the 2nd bottom plate i cut out. The first one was way to short lol but i think im getting that hang of it. As of now i have it filed to be an uniform as i can get it.
 
This is very inspiring...


$37 for the basic wedge:

P-HFZ-1_BACK.png


$50 for the Tone Bender style:


P-HFZ-2_FRONT.png

Yeesh!

GET BENT!
VERY INSPIRING to get bending my own...
 
steviejr92 said:
So i found out my bend radius is 1t of my total thickness. Which is .063". I think im right....lol
Click to expand...
You’ve arrived at a basic sheet forming rule of thumb: with a ductile enough material, the minimum exterior radius you can get on a bend is the thickness of the material. This is based on getting close to a 90 degree fold on the interior.

You can “pad“ the corner of your fold with an already bent sheet to get a larger radius, but this gets really finicky on something like a small box; the geometry is very close to what CAD would predict, but there is always a bit of deforming (usually stretching) that happens. Even the pros that specialize in sheet metal work toss out a lot of attempts. Accept this as part of a learning curve.

(I did simple forming in my shop, but tended to send out complicated forms. Finding a precise sheet metal shop is harder than you’d think. Luckily, by the 2000s there were a few local one that specialized in electronic chassis work, who could almost always meet my specs. @temol has been adding great comments to this thread!)

Also, be aware of the alloys that you order; some aluminum is easy to bend (1100 is great in this regard, but harder to source in small quantities; 6063 is common and good, 6061 not so much…) and others are more brittle. I always need reminding, and this page is a good brief rundown:

www.mcmaster.com

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.
www.mcmaster.com www.mcmaster.com
 
Alan W said:
You’ve arrived at a basic sheet forming rule of thumb: with a ductile enough material, the minimum exterior radius you can get on a bend is the thickness of the material. This is based on getting close to a 90 degree fold on the interior.

You can “pad“ the corner of your fold with an already bent sheet to get a larger radius, but this gets really finicky on something like a small box; the geometry is very close to what CAD would predict, but there is always a bit of deforming (usually stretching) that happens. Even the pros that specialize in sheet metal work toss out a lot of attempts. Accept this as part of a learning curve.

(I did simple forming in my shop, but tended to send out complicated forms. Finding a precise sheet metal shop is harder than you’d think. Luckily, by the 2000s there were a few local one that specialized in electronic chassis work, who could almost always meet my specs. @temol has been adding great comments to this thread!)

Also, be aware of the alloys that you order; some aluminum is easy to bend (1100 is great in this regard, but harder to source in small quantities; 6063 is common and good, 6061 not so much…) and others are more brittle. I always need reminding, and this page is a good brief rundown:

www.mcmaster.com

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.
www.mcmaster.com www.mcmaster.com
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I just ordered another sheet of 5052 aluminum since i already worked with it. I was really thinking about going with 3003 aluminum. I read that thats the best candidate for bending. 1100 i havent read up on but will be doing! Thanks a lot for the this info!
 
As far as production bent enclosures, I picked up this MDC432 from digikey. It's a cute box, not big enough for more than a simple fuzz I think, but they come in bigger sizes. This one was only $11. I'm not sure how well they would hold up to repeated stomping since they are fairly thin aluminum, but I haven't heard any complaints about this one I sold so hopefully it's good

IMG_8126.jpg
 
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