Getting marbles into the beetle’s belly

One tricky aspect of this project was the need to allow viewers to interact with the marbles. This beetle-shaped rolling ball sculpture, has a long tongue, that people will be able to roll a marble down. Slowing down a fast-moving marble was a key. I used a series of springs, cups and switchbacks to reduce the speed of the the marbles, especially as they neared the lift chain.

Chain lift for the rolling ball sculpture

OK, time to try another solution. I bought some chain and two new sprockets for the existing electric motor. I mounted the motor under the skeleton of the beetle. Actually, I like the positioning of this setup better. The chain will have eight cups attached to it. These will carry the marbles to the top of the sculpture.

Trouble with the lift screw for the beetle

I tried. I really tried. But the Archimedes screw lift got the best of me. I thought everything was looking good. The screw lift is more than six-feet tall. A lot can go wrong in something that long. If the screw is not true, it will not lift the marbles properly. Here is a photo of the screw before being attached to the motor.

Next, I attached to motor and gear mechanisms to the frame of the bug. Alignment is key. I used two gears, so the screw would turn counter-clockwise.

In the end, the screw lift was a little bit off. The marbles worked their way up the lift about halfway, before tumbling back down. So frustrating. But, this is a learning experience. Time to try another way.

Rolling ball sculpture grows legs

Time to finish the legs on this beetle. As you can see, lots of high-tech leveling equipment. A few boards and bricks and we're ready! Each leg has a solid steel ball for a knee cap or leg segment.

All finished. The beetle now has six properly-scaled legs to stand on. Definitely building from the ground up.

The beetle gets a shell

OK, after the frame is finished, it was time to roll some tube. I used a simple tube roller (Harbor Freight Tools) to help (see it in the background, attached to my welding table). It helps to have a set of extra hands, especially with a long roll. So, I recruited my son and his friend to guide the tube while I turned the wheel. I used three sections of 1-inch tube to create the shell. A few welds later and a graceful form was born.