Marble Coaster Track Clips

thingiverse

This Thing contains a set of 3D-printable clips that can be used for building a marble run or marble coaster. The clips are designed to securely hold 1/4" (outside diameter) polyethylene tubing which serves as rails for guiding a 1"-diameter marble along the track. The tubing just snaps into the clips. I used tubing from Lowes. (The tubing I saw at Home Depot had a somewhat elliptical cross-section which might not fit as well in the clips.) A 25-foot roll of tubing was just enough to make the coaster you see in the photos. Here are links: https://www.lowes.com/pd/EZ-FLO-0-170-in-Inner-Diameter-x-150-ft-Polyethylene-Tubing/1000365053 or https://www.lowes.com/pd/EZ-FLO-0-170-in-Inner-Diameter-x-25-ft-Polyethylene-Tubing/1000180489 Some of the clips have flat brackets with screw holes which allow you to secure the track to the supports at 0, 30, 45, 60, and 90 degrees. The holes in the brackets are sized to snugly fit #6 pan-head screws. The clips with no bracket were spaced at 10-cm intervals along the track to hold the rails a uniform distance apart. Once the 3D printing was done, I built the coaster shown in the photos as a proof of concept before I ask my students to design and build their own. It took about twenty minutes using scrap wood and screws I had on hand. Although I imagine any 1" ball will work, the ball I use in my marble coasters is a 1"-diameter solid plastic ball from Pasco Scientific (comes with their physics projectile launcher). They can be bought from Pasco in packs of ten: https://www.pasco.com/products/lab-supplies/other/me-6822 I've posted a separate Thing which is a 3D-printable ball launcher designed for the same poly tubing coaster: https://www.thingiverse.com/thing:5279476 Fellow physics teachers: If you use these clips with your students I'd love to hear about how your activity went! And I'm always looking for tips for improving this project for my students. My Twitter is @Misterfizzx .