I'm trying to use this sheet to get an idea of the loading involved with one of our large excavators but am having trouble adjusting the x,y co-ordinates and dimensions, how hard is it to adjust the parameters to suit a different machine with this sheet?

What we are trying to do is illustrate the increased loading on the machine- in particular the H-link joints noted as h,j,i,g on your sheet from using the bucket to walk down a ramp-ie: taking the machine weight to allow the tracks to move down the ramp easier.

This is not good practice and is significantly wearing our H-link bushings and misaligning the attachments bores for each clam linkage.

To adjust chart XY scale to fit the new geometry use XLC's "Chart XY Scales" button . This only works with XY scatter Charts. The button toggles between automatic XY scaling (to fit the chart window) or an equal scale for the X and Y axis (square grid). This should sort out your problem.

You should be able to adjust your geometry as you like to investigate the worst configuration of the machine with regard to H link. I hope this helps Ryan.