With the release of Zwift’s FutureWorks steering, Zwifters everywhere are mounting smartphones to their handlebars and turning them to and fro. To avoid wearing a hole in your carpet, trainer mat, and/or tire, it’s best to have something under your front wheel to help it turn smoothly.
Trainer manufacturers are starting to release swiveling riser blocks that can help, but they’ll take a bite out of your wallet. So why not just make your own?
In this video, Shane Miller takes us through how to build a low-budget swiveling riser block to use with steering on Zwift. You can find the parts at any hardware store, and it’s not too hard to put together. If you prefer a nearly ready-made solution, just buy a Lazy Susan and make a couple easy changes.

Having the Climb (as I do), would be a bad idea to try to turn the front wheel.
Mount a turntable under the riser, then the whole thing will turn.
I followed a close variation of Eric’s instructions and was very happy with the solution. His clear, step by step instructions and the forethought to put a hole in the board to mount the lazy susan worked great. I don’t have a mitre saw, so I have to improvise on the angled block underneath, but I found that an old metal paint roller tray (turned upside-down) worked well to hold my mounted lazy susan and provide enough of an angle that it all worked out. As shane said, they’ll be commercial solutions soon enough.
About the centering return force issue: I have a short bungee cord hooked over the brakes to the spokes. The cord is looped under the cable adjusters on the down tube to the crank. Does a pretty good job and no fame wear marks after months of use.
I was lazier. I found a garbage can dolly at Home Depot (~$35). It’s got five wheels and is easily able to handle the weight of the front end. All I had to do is cut a channel along the center which allows the front tire to sit in it, and also keeps the bike more level. The dolly pivots, rolls, and twists with the fork movement, without adding significant lateral, fore/aft, or up/down force on the frame/trainer. Photo available, if desired.