Sheet 01 of 12
Sheet Metal Rules Explained (Thickness, Radius, K-Factor)
In 5 minutes you'll set up a sheet metal rule and see exactly how thickness, bend radius and K-factor change the flat length of a bent part.
- Part
- Sheet Metal Rules
- Rule
- Steel 2mm
- Sheet
- t 2 · R 2 · K 0.4
- Time
- 5 min
- Status
- Open
OP 10Watch
Video in productionBuild along with the steps in OP 30 meanwhile.
Chapters
- 00:00What a rule is
- 00:40Make a rule
- 01:40First bent part
- 02:40Change the K-factor, watch the flat length
- 03:50Common mistake
- 04:20Your 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.
The model shows part A, for illustration. Your part has its own sizes: build it from the drawing in OP 30.
OP 30Build it in SolidCraft
Part A of 8. Every learner gets a part with its own sizes, so the values you check below are yours to find.
A new part has new sizes. It clears this sheet's checks and ticked steps; your quiz answers stay.
The picture shows part A, for illustration. Build your part from the drawing and the sizes listed here.
- Rule
- Steel 2mm
- Thickness
- 2 mm
- Bend radius
- 2 mm
- K-factor
- 0.4
As typed in this exercise
- Sketch Base on XY: rectangle (0, 0) to (100, 60)
- Flange: height 30
- Physical Material: Steel
Your task
Make this bracket in SolidCraft 0.22:
- A sheet metal rule called Steel 2mm: thickness 2 mm, bend radius 2 mm, K-factor 0.4. Make it the active rule.
- A sketch on the XY plane with a 100 × 60 mm rectangle, corner at the origin. Finish the sketch.
- Flange on that sketch: this makes the flat base.
- Flange again on the long front edge: height 30 mm, angle 90°.
- Click Flat Pattern (Sheet Metal tab › Flat) and write down the flat size.
- Right-click the body in the browser › Physical Material, set Material to Steel, OK. Then right-click the top row of the browser (the whole design) › Properties and write down Mass.
Then change only the rule's K-factor to 0.33 and look at the flat pattern again.
What to write down
- The flat length across the bend with K-factor 0.4.
- The same length with K-factor 0.33.
- The bracket's mass in steel, in grams (type the number only).
Type both below and press Check. The other side of the flat pattern is 100 mm in both cases: the bend runs along it.
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.
Show the drawing and bend table
exercise · Steel 2mm · t 2 · R 2 · K 0.4 · all dimensions in mm, from the blank's left and bottom edgesFlat blank 100.000 × 86.398 mm · 1 bend
| Bend | Angle | Dir. | R mm | Length mm | Allowance mm |
|---|---|---|---|---|---|
| 1 | 90° | up | 2 | 100 | 4.398 |
exercise-k033 · Steel 2mm · t 2 · R 2 · K 0.33 · all dimensions in mm, from the blank's left and bottom edgesFlat blank 100.000 × 86.178 mm · 1 bend
| Bend | Angle | Dir. | R mm | Length mm | Allowance mm |
|---|---|---|---|---|---|
| 1 | 90° | up | 2 | 100 | 4.178 |
OP 50Quiz
Q1Where do you set the sheet thickness?
Every sheet part takes its thickness from its rule, so changing the rule changes them all.
Q2What does a larger K-factor do to the flat length?
The neutral line sits further out in the bend, so more material goes round it.
Q3By default, where does a flange's bend radius come from?
The rule gives the bend radius unless you change it in the flange.
Every value is within tolerance. This sheet is done.
Sheet 02: Base Flange