Optimal V-Die Selection Formula for Sheet Metal Air Bending

Learn how to determine the optimal V-Die opening or Die Size for sheet metal air bending.
Skip to final Equation: [4:50]
Believe it or not, there is a science to the "art" of sheet metal air bending. Many people use rules of thumb to select brake press die opening. These rules of thumb are often inconsistent and may lead to unsafe or less-that-ideal conditions for sheet metal forming. I will show you how to derive an equation that will give you the optimal die opening for any combination of inside radius, sheet metal material thickness, and bend angle.
- - - - - - - - - - - - - - - - - - -
Die Selection Matrix:
• Determining Optimal Di...
Full Playlist:
• Sheet Metal Forming
- - - - - - - - - - - - - - - - - - -
Check out my channel for more videos and tutorials for engineers!
Like, follow, share and don't be afraid to drop me a comment/message with feedback, questions, or video suggestions!
Thanks for watching!
Channel Link: / @theengineeringtoolbox...
- - - - - - - - - - - - - - - - - - -
Other great content!
Top Free Engineering Software:
• EVERY Engineer Should ...
- - - - - - - - - - - - - - - - - - -
Follow and interact!
Twitter: / theengtoolbox
Facebook: / theengineeringtoolbox
- - - - - - - - - - - - - - - - - - -
#SheetMetal
#SheetMetalForming
#PressBrakes
#EngineeringToolbox
#EngineeringTutorials
#ManufacturingEngineering

[@staffanoberg2538]

If there are high surface finish requirements when edge bending/press brake, the Swedish product Tribotextil™ can be applied in the bending/pressing tool and mechanically protect the sheet metal from scratches and other damages. Tribotextil™ is an extremely thin and very strong textile that in this process replaces lubricants in the tool.

[@TheEngineeringToolboxChannel]

Thank you for sharing. Also the V-Series Black by Wilson tool will reduce die marks, use less bend force, and lessen unwanted material deformation when features are close to bend lines.

[@jaydeeppanchal6662]

Amazing knowledge! Thanks

[@prashanthbiligere]

Good One!, I appreciate your time. I have a request regrading bending. how do you make air bending for angles such as 20, 15, 55 degrees etc., which are non standard..? and how do you verify the angle after bend?

[@TheEngineeringToolboxChannel]

A precision protractor like the link below is used to verify angles. The link below is a high quality tool..very precise. depending on your needs, there are cheaper versions out there. a.co/d/efZWOsE

[@ganishk3568]

sin(t)/tan(t)=cos(t) After simplifying the formula becomes more easier.

[@EtienneLeMerrer]

Excellent explanation ! Where could we download that excel sheet ?

[@TheEngineeringToolboxChannel]

Here is how you can create it for yourself. kzbin.info/www/bejne/eWfFlYqeoatof5I

[@cruorr]

My first thoughts towards "these rules of thumb are open to guessing etc" was yeah no theres a science we just have bent and rusted shit LOL

[@carlpatterson1212]

The company I work for uses a 1" die for everything. Is there a way to determine what the radius will be across varying thicknesses while using only a 1" die?

[@cafiveohsrockbandremix9254]

It depends what material you are bending and whether you are bottoming or air bending. If you are air bending aluminum parts, you're probably getting an approximate inside radius between .13 and .15 (13-15% of die opening) and your outside radius will be material thickness + inside radius. If you're bending steel, your radius is probably 20-22% of the die opening. Check out the article "Bending Basics: How the inside bend radius forms" on The Fabricator website for a better explanation

[@TheEngineeringToolboxChannel]

Couldn't have said it better myself!

[@حمزةجمعةعبدالقادر]

When do we multiply by 6, 7 or 8..... to get the value of V die??????

[@TheEngineeringToolboxChannel]

The point of the video was to show that you shouldn’t! Instead use the calculation shown 👍

[@3D-Channel]

If I use beggar V, like 20 mm more V length than the standers one, is there any problem I may face?

[@TheEngineeringToolboxChannel]

Not necessarily any problems. But you should be aware that with air bending the die opening affects the radius of the bend....and therefor affects your bend deduction values. If the flat was made with a certain bend deduction in mind and you change the die it can affect your formed dimensions.

[@NonServiam1312]

Seems like doing all the calculations before starting production would lead to an unacceptable amount of setup time where I work. I'm new to press break and received minimal training so I'm stuck trying to figure this shit out on my own.

[@TheEngineeringToolboxChannel]

Should be able to do the calculations ahead of time and create a lookup table/matrix for easy reference on the floor. Check out this video. kzbin.info/www/bejne/eWfFlYqeoatof5Isi=sIB40Kmb2s4k4oUa Also, most companies these days are using automated press brakes where tooling is selected and predefined in the program. In those cases these calculation are done “off-line” when decided what tooling the program should use. Or even built into the programming software so tooling is automatically selected without needing someone to manually decide. This way the program tells the machine and operator what tooling is used for consistent part geometry.

[@NonServiam1312]

@TheEngineeringToolboxChannel I'm using an old Toyokoki, the software it runs is from 1996. It's doesn't have all those fancy features. I'm constantly having to apply tape to the back gauges and shim the dies to compensate for tapering along flange length and angle. Pain in my ass. I'm definitely going to keep this channel handy, though. Thanks.

[@ganeshgandhi4643]

Sir this formula is applied only to the air bending in press brake machine or we can use this formula for designing a V-bending tool for power press.

[@TheEngineeringToolboxChannel]

This formula is for air bending using standard press brake tooling.

[@IEA_455]

12x material thickness WTF bending 12 gauge on 30mm die is insane. I use 6x every time

[@TheEngineeringToolboxChannel]

Agreed, but it ultimately Depends on the punch radius and bend angle as well. Hence the point of the video.

[@arsham194]

Holy moly, that narrative is so fast and there is no example. Thanks anyway.

[@TheEngineeringToolboxChannel]

Sorry about that! 😬 Edit: check out this video. Shows some calculated examples. kzbin.info/www/bejne/eWfFlYqeoatof5I

[@TheEngineeringToolboxChannel]

@KushyKaar420 in my experience this method works very well regardless of material thickness and punch size combination. In fact, it that is where it is most useful. Happy to be proven wrong though! Using this method for 3”R in 20ga mtl would suggest a ~8.5” die opening for air bending. What die opening would you suggest for this scenario? And how would you determine it? This is another video that goes further with some examples of more standard scenarios but I’ve certainly used it for odd-ball punch mtl thickness combos as well. kzbin.info/www/bejne/eWfFlYqeoatof5I

[@nihaldubey7491]

Very low voice