Very fine thread M10 grub screws

[John McNamara]

Hi

If you are going to set a machine up using jack screws the frame members will end up only touching at a few points, while this may achieve good frame geometry and depending on the fasteners and jack screws used if they are big enough, sufficient static load strength of the frame.

However machines with rotating components and moving frame elements will also impose dynamic loads and vibration, vibration in particular has to be damped out by the mass of the machine and maybe vibration damping elements.

Any fixed joint gaps left after jacking machine members into alignment need to be filled. Metal filled epoxy is used my many modern machine builders to do this.

Eberhard Bambergs excellent paper on Precision machine design, and in particular vibration is well worth reading. Link Below.

http://www.mech.utah.edu/~bamberg/re...e%20Design.pdf

Regards
John