Methods and apparatus for construction of machine tools

A positioning tool apparatus comprising, in combination:

• first and second parallel tubes filled with cement separated from one-another and acting as first and second end blocks respectively for a single-axis linear motion stage the first and second end blocks either rigidly attached to a base plate or rigidly attached to one-another;
• each of the first and second end blocks having two guide seat holes, each guide seat hole aligned with a corresponding guide seat hole on the other end block;
• left and right parallel guide shafts extending between the end blocks, each guide shaft pressed into, or cemented in place in, the first end block at one end and the second end block at a second end;
• a carriage configured to ride on the guide shafts, the carriage having right and left sides, the right side of the carriage having a through-hole passing through the carriage fore and aft containing a pressed tubular bearing, the right guide shaft passing through the pressed tubular bearing;
• the left side of the carriage having a notch configured to receive a pair of floating tubular bearings, one fore and one aft, the left guide shaft passing through both floating bearings, the pair of floating bearings attached to the carriage with glue or epoxy;
• whereby,
• the carriage moves fore and aft along the guide shafts forming the linear motion stage.