## Rectangle Block Unit in PreQuilt
**Rectangles** are manipulated squares in PreQuilt. You start with a square and stretch it either horizontally or vertically to create your rectangular block unit.
And since the idea behind this series is to build a block unit (not an entire block that is just a rectangle), I'm going to create a 12" finished block that includes rectangle block units (like for example, the **Rail Fence** quilt block).
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### Help Guide
1. Click on the **BLOCKS tab** on the left side control panel.
2. Click on the **Make Custom Block** button.
3. The **Block Editor panel** will slide out and overtake your screen. My block is set to 12" x 12" finished, but it doesn't matter, the next steps will work for all sized blocks.
4. Set your grid guidelines by changing the number for the horizontal and vertical units.
* Since I'm going to be creating the **Rail Fence** quilt block, I'll set my gridlines to 1 horizontal and 3 vertical units.
5. Click on the **square shape** () from the central control panel.
6. One square will be added to the block space. Because the horizontal unit is 1, our square block unit will fill the entire space.
7. To manipulate the square into a rectangle, **grab** the square on the bottom side of the square and **drag** it until the square fills the height of only 1 horizontal grid space.
* Note: If the snap to grid is turned on (default) then the shape will automatically fill the grid space.
1 x Rectangle block unit
8. To finish the Rail Fence block, click on the **Clone button** () on the central control panel.
9. Click on the **Link button** for a different fabric link (so that there are now 2 different fabrics being used). In this example, I am using Fabric Link B.
10. **Move** the new rectangle block unit into one of the empty spots.
11. **Repeat** 3 Steps 8-10 to finish the Rail Fence block.
Rail Fence with 3 rectangle block units
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## Sewing Construction Diagrams
No sewing construction diagrams necessary.
Simply cut your square to size and it's a completed block unit ready to be used to create a larger quilt block.
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