Tennis Tutor to Pickleball Tutor Conversion Kit

thingiverse

I own a Tennis Tutor and couldn't believe that the Pickleball Tutor costs over $1,000. It's essentially the same machine as the Tennis Tutor with slightly smaller wheels and fewer features. I decided to create these smaller wheels and modify a few things. The result works great and is easily convertible back to a Tennis Tutor within about 5 minutes. If you're new to 3D printing or don't own a machine, don't worry - there are links on this page to pay for printing and mailing the files. I made a YouTube video tutorial that I'll link at the bottom of the page. You can also check my "Make" pictures here for a reference point. To start, remove the top of the tennis tutor and loosen the 1/4"-28 hex head set screw in each wheel hub. I've created two versions of my replacement wheel - one with threads already installed, and another that requires a $30 helicoil thread repair kit. Regardless of which version you choose, you'll need to buy #82 rubber bands to create a double layer on the wheel. I used spray adhesive to hold them together. You'll also want to print 4 spacers, which will allow you to move the ball hopper spring and cover up for the wider pickleball. Use two more spacers to lift the chute up slightly. With these modifications in place, you'll need longer bolts - specifically 4 x #8-32 x 1", 2 x #10-32 x 0.5", 1 x #10-32 wingnut. The big thing is to use #82 rubber bands to create a few full flat layers of rubber on the surface of each wheel. Use spray glue to hold them together, and build up your layers until you get a nice squeeze between the wheels. A couple of extra tips helped me increase the consistency of the feed: I slightly sanded out the drop hole where the pickleball enters the chute, which reduced pinched balls by 10%. I also used velcro to keep the top of the rubber ball chute fixed to the metal drop hole, which significantly reduced bad feeds. Please feel free to improve on this project and message me with any suggestions. You can find my YouTube tutorial here: https://youtu.be/84-hZMmlD7M. This thing was made with Tinkercad - edit it online at https://www.tinkercad.com/things/5jX5WIY12Fu. Update: I found a better solution than the Helicoil threads - EZ-Lok 1/4"-28 thread inserts, which I've linked on Amazon. They lock the wheel down super well, making the machine quieter and more consistent. I'm using them on both sides of each hub for better weight balance and stability.