Build Thread- will this work(small Zaxis)

[zeed]

I got one small linear acutator and was wondering could this be used as Z axis on a small cnc?
I has 70mm travel and 6mm rods with 4 linear bearings.
It had a small pneumatic piston in the middle witch I removed and replaced with threaded rod.
I also plan to support the 6mm rods on boath ends...

[LeeWay]

Probably not.
It has no means of supporting itself. Most Z axes are supported on both ends with a sliding part that runs between the two end supports.
Some are a little different by being fully supported, but the result is a carriage that moves between point A to point B.
With this one, you only have one moving element and when extended, is not supported.

[CarveOne]

Originally Posted by zeed I got one small linear acutator and was wondering could this be used as Z axis on a small cnc? I has 70mm travel and 6mm rods with 4 linear bearings. It had a small pneumatic piston in the middle witch I removed and replaced with threaded rod. I also plan to support the 6mm rods on boath ends...

I agree with LeeWay. Also, 6mm rods are very small for a Z axis that will have any amount of side load on it while cutting.

You may be able to use it for making a CNC pen plotter.

CarveOne

[zeed]

OK.thanks for your replies,I am in the middle of my new machine build and was hoping that this will be my Z axis.
Well,back to the drawing board.

[baithog]

Well, why not - Screw the rod supports at each end to a plate that you attach to the Y-axis trucks? Make the threaded rod in the center long enough to attach a motor coupler or a pulley.

The real questions would seem to be:

• Are the bearings on the support rods tight enough for the spindle and application?
• Is it strong enough, rigid enough to support your spindle?
• Can you reduce the backlash in the screw to acceptable levels?
• can you fabricate a spindle mount that will fit on the carriage?
• Can you live with the minimal travel?

Larry