Step 1. Run a work plane through your case so it runs perpendicular to the panel or side of your case.

Step 2. Create a second work plane where you want your partition to stop, so for example you wanted to produce a partition that is 150mm wide, then you would create a work plane offset at 150mm from where you want the partition to start.

Step 3. Create your partition along the first workplane you created, if this partition doesn’t intersect with existing partitions then it will show up green, if it does happen to intersect it will show up as red.

Step 4. Select the end face that is opposite to where you want the partition to start from.

Step 5. Snap this selected end face to the second workplane you created.

Step 6. Adjust the sizes ( height, width) if necessary, click the green tick to confirm the new short partition.