Time for Y axis drive. Gantry legs will be connected under the bed by flat steel 50x5mm.
I will use only one ballscrew for moving the gantry as this is desktop size machine (travel distance from left to right is 300mm, forward and backwards only 220mm).
I sacrificed 80mm of travel on Y for bigger distance between bearing block - stiffness won.
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Had to fabricate Ballscrew nut bracket today - picture later.
Than I can center the ballscrew mount (front and back) so there is no tension on screw when turns backwards/forward.
A lot of steps in fabrication depends on previous - all related. Can not jump forward without doing something which have to be done first. Sometimes I loose the plot and do something what shouldn't be doing at that time like - pick up for sensors:
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or sensor bracket/s