Do 20A flex wheels expand at high speeds? Like flywheel 2500+ RPM Speeds

Currently designing my team’s robot in CAD, but I have a 0.015in gap between the flywheel and disc. I was wondering at the high speeds the wheel is running at, is it possible that the flex wheel will touch the disc? And does anyone know the exact distance a flex wheel will expand at high speeds?

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flex wheels definitely do expand significantly when spinning at high velocity. I couldn’t tell you how much, that would vary on a lot of factors. But it would certainly be more than 0.015"

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It depends on the flex wheel. 60a (the black ones) barely expand at all at 4200 from my testing. 45a (dark grey) expand a little more, and 30a expands quite a bit.
What I found works well for varying compression is to give yourself a good gap between the flex wheel and the backing piece, maybe 1/8" or 3/16", and use antislip mat or adhesive foam to slowly decrease the gap until you find something that works well.

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Pur team did a sw analysis on how much the wheels expand at 4200rpm. The 30a expand .5in and the 60a expansd.19

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Banking on this. as the new launcher design requires a .3in gap between disc and flywheel.

Keep in mind that this will probably vary from what he found; he found this off of a cad program analysis, while you are doing this in real life. These numbers will most likely vary some based on how you mounted them, what speed you are spinning them at, etc.
But you should definitely keep these numbers in mind when you design, they seem like a good basis.

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