Thanks to the Laser cutter at my university my massive mess up with the wheels has been resolved.
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It takes about 5 mins per wheel but I was able to re-cut each hole. I set them up to sit in a piece of 9mm MDF board with a series of 73mm holes in. I put each wheel in a hole then cut a 19mm hexagon into each wheel. The cut was 0.3mm larger than the input so it came out at 19.06mm per hole which is a very tight fit on the 19.5mm hex shaft
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Afterwards I am left with some perfectly straight wheels and these random little bits of plastic.
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