Sheet 04 of 12

Flanges on Several Edges: Corners, Gap and Corner Reliefs

Q: Why pick all four edges in the same Flange?

Only flanges of one feature have their corners closed toward each other. The corners are closed, with the rule's gap, only between flanges of one feature.

Q: Where does the gap between two walls at a corner come from?

The Flange Gap in the sheet metal rule. Flange Gap is a rule value; by default it equals the thickness.

Q: You switch the corner relief from Notch to Round. What changes?

A round cut at each corner, and shorter bends. The round relief is cut out of the corner and the bends stop where it begins; the flat size stays the same.

In 6 minutes you'll fold up all four walls of a tray in one Flange, see how SolidCraft closes the corners with a gap, and choose a corner relief shape.

Part: Corners and Reliefs
Rule: Steel 2mm
Sheet: t 2 · R 2 · K 0.4
Time: 6 min
Status: Open

OP 10Watch
OP 20Turn the part
OP 30Build
OP 40Inspect
OP 50Quiz

OP 10Watch

Video in productionBuild along with the steps in OP 30 meanwhile.

Chapters

00:00A tray from one flat sheet
00:30The base
01:00Four edges, one Flange
02:00The corners and the Flange Gap
02:50Corner relief shapes
04:00Read the bends in the bend table
04:40Common mistake: one wall at a time
05:20Your exercise

OP 20Turn the part

Drag to turn, scroll or pinch to zoom. Flat shows the blank before it is bent: the same sheet, the same frame.

OP 30Build it in SolidCraft

Your task

Make this tray in SolidCraft 0.21:

In a new design, make the rule Steel 2mm (thickness 2 mm, bend radius 2 mm, K Factor 0.4), Active rule ticked. Leave its corner values as they come.
Sketch a 120 × 80 mm rectangle on the XY plane, corner at the origin. Finish the sketch.
Flange on the rectangle: the base.
Flange again and click the top edges of all four sides: the long front edge first, then the others going round.
Height 25 mm, Angle 90 deg, Bend Position Inside. OK.
Click Flat Pattern (Sheet Metal tab › Flat): write down both numbers of Flat size.
Click Export Bend Table…, save the CSV, open it and write down length_mm for bend 1.
Edit the flange (double-click it in the timeline), open Advanced, set Corner Relief Shape to Round and leave Corner Relief empty. OK.
Export the bend table again and write down bend 1's length_mm.

What to write down

Both numbers of the flat size (they don't change with the relief shape).
Bend 1's length with the Notch corner (the rule's default).
Bend 1's length with the Round corner relief.

Bend 1 is the first edge you picked. Type the values below and press Check. The bend table opens in any spreadsheet app or text editor.

OP 40Inspect

Enter what SolidCraft shows you. Each value is checked against SolidCraft's own result, within the tolerance shown. Nothing you type leaves this page.

Flat size, first number ± 0.05 mm mm

Flat size, second number ± 0.05 mm mm

Bend 1 length with the Notch corner relief (length_mm in the bend table) ± 0.05 mm mm

Bend 1 length with the Round corner relief ± 0.05 mm mm

Show the drawing and bend table

exercise · Steel 2mm · t 2 · R 2 · K 0.4

Flat blank 162.797 × 122.796 mm · 4 bends

Bend	Angle	Dir.	R mm	Length mm	Allowance mm
1	90°	up	2	112	4.398
2	90°	up	2	72	4.398
3	90°	up	2	112	4.398
4	90°	up	2	72	4.398

exercise.solidcraft exercise.json

exercise-round · Steel 2mm · t 2 · R 2 · K 0.4

Flat blank 162.797 × 122.796 mm · 4 bends

Bend	Angle	Dir.	R mm	Length mm	Allowance mm
1	90°	up	2	104	4.398
2	90°	up	2	64	4.398
3	90°	up	2	104	4.398
4	90°	up	2	64	4.398

exercise-round.solidcraft exercise-round.json

OP 50Quiz

Q1Why pick all four edges in the same Flange?

Q2Where does the gap between two walls at a corner come from?

Q3You switch the corner relief from Notch to Round. What changes?