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I'm looking for ideas, please, on modifying a new fiberglass KLM case. This is for my Willson 3050RZ, which weighs about 27 pounds. The disadvantages of the factory wheels are:

--small diameter (creating a tendency to hit hard every crack and chipped spot in normal concrete sidewalks), and

--too close together (causing the case to oscillate from one wheel to the other upon hitting small bumps, and nearly to tip over during turns).

Obviously, the two wheels are mounted on two short axles--instead of one longer axle--because the case folds open. There's not a lot of support structure for the axles, and the fiberglass is fairly thin.

Maybe a pair of bicycle training wheels is in order? Thanks for your comments and ideas.

Years ago I met a guy who machined some nylon clips that would accept the wheels from his pull type golf cart. He attached two sets of them to his tuba case. One set was placed down where the wheels could run on the ground and the other set was placed on top of his case so he could remove them and store them easily when he didn't need them. I imagine with wheels this large he could probably even do steps. The wheels are both on one axle so the whole off and on process was very easy. Seeing them made a lasting impression on me.