bra- definition k for sheet metal development

[Giancesa]

hello to all
on a couple of calandered pieces I found a remarkable difference between calculated development and real piece: with correct design development, I close and I miss 10-15 mm on the theoretical diameter value.
The error seems to me to be attributable to the fact that I used a sheet rule with a k for normal folds and no grilling.
in cad3d forums I found arguments where someone gave value to k 0.5-0.8.
I have remade the development and I have a difference now of 4-5 mm compared to before, but no 10-15 mm as it happens to me in reality.
I admit I'm not an expert on sheet metal and I'm just trying, so I'm definitely making some mistakes.
Thank you.

 

[Giancesa]

I found the hippo. After processing profiling, changes development, shortens. I have a video to show it all, but I don't know how to attach it, so maybe someone kindly can give me some explanation if inventor has a mistake or I'm wrong. Thank you.

 

[Matteo Cappelli dis.CAD]

Hi.
based on my experience, the factor k with the kalandrate is = 1
to today I have always had match between the real and the viode files

Good job

 

[Giancesa]

You know how to upload a video here in the discussion, so I'll show you the modeling problem, thank you.