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Spacers or shims can be added to fill in gaps from CAD inaccuracies, but the chassis would need to be cut if an intersection becomes apparent. Better to design with the intent of adjusting the amount of gap; leave room in the current CAD between chassis members and sheet metal.

5.0 Random Thoughts

Since the bottom panel is getting reinforced, as well as the chassis, might there be a way to solve both with a single solution?Concept 1 has a strong base idea, but lacks the adjustability to fill the gap between the chassis and sheet metal.

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Concept 2 improves on Concept 1 by introducing a degree of freedom. However, the design would be improved with some way to rotate the holding plate in the Z-axis (if the Z-axis is up). As a side note, some of the adjustments to ensure a good fit can come from cutting the sheet metal correctly.

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I have not been able to include the ability to rotate yet. I have some ideas in mind using spherical bearings, however, I think that may be over-engineering the design. Any suggestions would be great!