Jonathan,
I have altered the acceleration setting to 300 and this seems to be ok. I did try 500 but this wa a bit too abrupt for the machine, it was shuddering a bit at start and stop. I need to email Gary at Zapp to see if it is possible to alter the acceleration and deceleration distances in the software. If this can be changed then I could have a bigger acceleration value.
The new bed for my machine arrived yesterday but this needs a fair bit of work to get it finished to what I have planned. Its 15mm thick aluminium at 1260mm x 910mm. It needs to be cut to 1250mmx900mm then fitted, levelled and drilled and tapped for clamping.
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Regards

Ian