Bob Knetzger

Bob Knetzger

Bob Knetzger ([email protected]) is an inventor/designer with 30 years of experience making fun stuff.

Latest from Bob Knetzger

assemble glider

Follow these steps to turn a foam plate into a soaring falcon! Read more »

TIN featured image

Here’s a fun tutorial that was used in a DIY project found in a past issue of Make: — the “EZ-Make Oven.” It featured an incandescent bulb, as a heat source, built into a paint can for baking plastisol creatures, aka Creepy Crawlers! Here is how you can make something else with the EZ-Make... Read more »

sandal test 3@72

Here’s a fun and easy project for summer: Hack a pair of flip-flops so they make designs in the sand as you walk. Just add a bit of Sugru to your sandals and start stamping! Read more »


Cartesian diver toy "Diving Tony" was a cereal box favorite. You can make one quickly from just a few parts. Use clear PETG tubing and a piece of solid styrene to make the diver follow your commands. Read more »


Perhaps the most iconic 80's music toy was the Magical Musical Thing from Mattel. The TV commercial featured a kid playing melodies with one finger on the toy’s keypad strip — and finishing by playing it with his head! Now you can make your own custom version! Read more »

M36 TIN bulletin chalk board

Make a simple blackboard/bulletin board that cleverly uses a yardstick to divide the two. It's quick, easy, and makes a great gift too! Another great project from Make: contributor and toy inventor Bob Knetzger. Read more »

Ouija Be Mine image5

Ouija Be Mine? Here’s an animated pop-up Valentine's card you can make in a few minutes. When you slowly open the card, a hand sweeps across and moves the heart-shaped planchette over the Ouija board, spelling out the message: “HAPPY VALENTINE’S DAY!” It’s both mysterious and romantic, perfect for any... Read more »