Hi all! I am a total newbie and just got my first K40, was really excited to see it do its stuff but have had nothing but trouble :(. To summarize (A LOT) the machine doesn’t seem to recognise the bed size or homing position. Regardless of the page size in LaserDrw or orientation to top left etc it keeps taking the head to bottom right and trying to engrave on the metal casing and thus making an awful juddery mirror loosening vibration noise. Anyone experienced this before?
Lots of issues come from poor connections. Regardless if this is the reason for your issue I’ll recommend you check each and every connection ( be carefully, disconnect from power).
if cutting i use 10mm/sec max,engraving 400mm/sec,anymore cutting machine will shake itself out of alignment
Thanks guys, will do. Probably wise to check connections especially since there’s a rattling/clicking sound coming from the controlpanel/mainboard area 
Are you really sure you set the machine & device id to match your board?
Also check to make sure the cables are in correctly so there isn’t one upside down & sending the head to the wrong corner. They should go in only one way, but maybe something shortcut by the factory on yours.
I have found that max speed I can use whilst cutting is 50mm/s without the juddering & shaking out of alignment. However, this varies depending on the complexity of the shape I am cutting. More complex shapes will need slower speeds due to the constant changing on direction.