Materials used in CNC build projects

[GeorgeD]

Hi Guys.
Most of you are talking about vibration being a major factor here when building a CNC in certain acoustic material.

For the life of me the only area I can see vibration emmitting is on the spindle Y axis? if we were to dampen the spindle were it is clamped to the Y axis with rubber seal then vibration would be kept to a minimum.
Any type of bearing/s should glide with precision and if it rattles then its poorly made.
We could also dampen the steppers with a piece of rubber matting at the face of where they're mounted.

[GeorgeD]

Whats the pros and cons over a fixed gantry and a moving X axis?

Since I'm going to tackle the CNC in perspex I thought it might be wise to have the gantry static rather than moving.

[FatFreddie]

For the life of me the only area I can see vibration emmitting is on the spindle Y axis? if we were to dampen the spindle were it is clamped to the Y axis with rubber seal then vibration would be kept to a minimum.

If you rubber mount the spindle, it will flex and reduce accuracy. Basically, for accuracy, you want maximum rigidity all the way from the tool tip to the work piece which means using rigid materials. Any form of damping that relies on movement will reduce accuracy, the only thing you can really do to control vibration is to increase the mass so that the energy going into the system is dissipated by moving the whole machine a very small distance. If the forces you are putting in are small, say a low power well balanced spindle cutting foam, or a laser then you do not need so much mass or stiffness.