Re: Drill-Mill CNC conversion design.

Carlos-

Thanks for looking at it. In the back of my mind I felt the need to
place a bearing up high in the assembly as you have stated in (1). I
will look at doing this.

CADMAN

--- In CAD_CAM_EDM_DRO@y..., "Carlos Guillermo" <carlos@v...> wrote:
> Nice layout, with one exception:
>
> I'd recommend using TWO angular contact bearings for the z-axis,
spaced a
> fair distance apart, for three reasons, in descending order of
importance:
> (1) it looks like the belt will be applying a side load to the
ballscrew
> assembly, which has nothing to resist it if you only use 1
bearing. Thus,
> you'd need 2 bearings, and they should be spaced apart to increase
the load
> capacity against the cantilevered belt tension. Standard angular
contact
> bearings can only take a load in one axial direction, and alone
have zero
> moment capacity. (2) angular contact bearings are meant to be
mounted in
> pairs for good reasons, like proper preload, alignment, etc. (3)
many forces
> are likely to exceed the weight of the headstock, such as those from
> drilling, friction of the quill in its bore, vibration,
accelerations, etc.
>
> Hope this helps,
>
> Carlos Guillermo
> VERVE Engineering & Design
>
> -----Original Message-----
> From: cadman@p... [mailto:cadman@p...]
> Sent: Wednesday, May 30, 2001 10:50 AM
> To: CAD_CAM_EDM_DRO@y...
> Subject: [CAD_CAM_EDM_DRO] Drill-Mill CNC conversion design.
>
> I have finished drawing up a design using Solidworks. I have placed
> some pictures and drawings on my web site. Before I start to make
> the parts to do this conversion, I would like to get the groups
input
> on the design.
>
> I did not show preloaded ballscrew nuts in the design, I figured I
> could add them if I was not happy with the tolerance that a single
> nut gives. The cost of the preloaded nut scared me away. My use of
> this machine will not be for business of any kind, just making parts
> for my entertainment.
>
> My web site is http://24.12.163.105/cnc/
>
> CADMAN