Why not use unsupported rails?

[Jonathan]

Enjoying your stress analysis so far - good work there. I think people are finding the pretty colours more interesting than my old spreadsheet of numbers.

Thanks - I used that spreadsheet a lot to start with.

You mention the bed analysis - any plans for stress analysis on other areas of a cnc machine such as gantry sides?

Don't see why not. Although I'm not sure what to compare there? I could model different thicknesses of aluminium plate, but that wont tell us much more than your spreadsheet did. What would you suggest?

[routercnc]

Hi Jonathan,

I was only thinking of various thickness plates vs RHS. Both cantilevered with one end grounded over an area representing a typical gantry end section (e.g 80x80 extrusion). For RHS the inside gap at the grounded end would also be filled in over the same area as the end of a typical gantry (e.g a spacer) since this represents the best bolted joint.

You are quite right that this is available in the original spreadsheet its just that your pictures are easier for most people to follow, and it is another question that gets asked on this forum. Just a thought since as this is now a sticky it might help newcomers to see the relative performance of common CNC machine designs if the analysis results are all grouped here.

Georgetheforge,
Sounds like a promising start based on the concept so far.