Bend radius

[LACHANDARA]

Hi,
Im new to sheet metal, what is the recomended inside bend radius for 6mm stainless steel.

Thanks

 

[berkshire]

6 mm
B.E.

 

[CorBlimeyLimey]

As a general rule of thumb, 1 X material thickness for the inside bend radius is acceptable. On thicker, less ductile material 1.5 X thickness is often preferred.

 

[Updraft]

Rules of thumb differ just as thumbs differ. I agree that a good guide for sheet metal is to use an IBR (inside bend radius) no less than the material thickness and preferably closer to 1.5x thickness, especially for thicker materials (over .100", 2.5mm).

However, the IBR specified is meaningless if the fabricator doesn't have it. Therefore if you plan to use IBR=t but the fabricator doesn't have that size you could get a surprise. It is always good to talk with your fabricator. He (she) will help you be successful.

For general designs you might look up the standard nose radii commonly available and then pick a size that is => t.

- - -Updraft

 

[drawoh]

LACHANDARA,

You should look through some material handbooks. Some grades of stainless steel are very ductile. I know that recommended bend radii for various grades of aluminium are all over the place.

--
JHG

 

[CorBlimeyLimey]

A good Press Brake operator doesn't need to have the exact radius punch. Air-bending offers control of the IBR via the die opening width.

For more details browser search for sheet metal air bending

http://sheetmetal.me/air-bending/

 

[drawoh]

CorBlimeyLimey,

I have had this discussion with a good sheet metal shop. They can bend "in air", but it is more expensive, and less accurate. You are better off conforming to their tooling.

--
JHG

 

[LACHANDARA]

Hi,
To all who answered my question, thanks greatly appreciated

 

[supercub]

Check out thefabricator.com, they have an article on bending that has alot of info.