I pump a lot of liquids (particularly veg oil) and I've tried a lot of cheap pumps (such as drill pumps and syphon pumps) but I found these didn't work that well. I wanted something specific to my needs, something custom built. I wanted it sturdy, reliable, practical and cheap.
After being inspired by a couple of fellow YouTubers I decided to make my own hand pump using simple some leftover PVC plumbing parts and a ping pong ball.
The resulting pump is reliable, simple and easily affordable. It shifts an impressive amount of liquid for its size and is very easy to build using just basic tools. All in all, a great hand pump that's worth making - even if you don't need it yet... because one day you'll be pleased you did.