Hey kids! Here's a way to make a free strainer for small cans of tuna. I made this at TechShop here in Austin, TX. This will be comparable to the type you would pay $5 for on Amazon or in a store! Go to www.Techshop.ws for more info.
Create a sketch of a circle with a diameter of 8 cm across as seen in pic 1. Click Finish Sketch. Now extrude it upwards 3 mm(see pic 2).
Now click Create New Sketch and select the top of the shape(pic 3). We'll measure a smaller circle with a diameter of 7.5 cm. This will mean the wall around it will be half a centimeter thick. That's plenty of strength.
Go ahead and use the same extrude procedure on the outer wall(pic 4). Extrude upwards 3 cm. That will be enough to sink it into a small tuna can enough to squeeze the water out.