Unfold sheet metal issue

Radu

Hello,
I have downloaded one month trial version Mechanical, and I tried to fabricate a sheet metal cassette for testing program. The problem is after bending the cassette has the length smaller with 2mm and width smaller with 3mm. The fabricator said the dxf unfold sheet is not correct and this is the reason the cassette is smaller. He calculate the unfold sheet 2 x thx - 1 for each 90dgr bend.
Can you help me with this issue, please? I'm thinking there is some settings that I've missed.
The sheet is 2mm thk, material is aluminum.
K factor is set for 0.325
Hem relative bend deduction is set for 3
Thank you for support.

RSW

Just reading this post... the bend radius(not hem relative deduction) in your drawing is still 2mm instead of 3mm.

Aside from that BricsCAD uses default values (e.g. bend radius is equal to material thickness, default K-factor etc.). Bricscad's unfolds are usually not right straight out of the box the first time with default settings because of this.

It takes creating a sample to test if the unfolding is correct and you may need to adjust things like K-factor, bend radius to match that of the toolset used on the bench press for your product etc. to get a correct unfold if those values are known on beforehand and then readjust afterwards if necessary.

If you want consistent accurate results one should create a bend table for each combination of material/bench press configuration.