Re: BP II duplicator conversion

Jon...Thanx for your input. I went over the machine again today and discovered the Z axis is not ball screw driven, rather it uses a hydraulic ram to raise and lower the knee. Too much project for me. I will wait for an easier unit to convert. Thanx again....Richard.

>
>
> k8zre wrote:
>
> >Advice please...I have access to a BP series II machine with the x,y,
> >and z axis all driven by hydraulic motors. The motors are controlled
> >by a device I am not familiar with but strikes me as being like a
> >digitizers with a probe. Push the probe in certain directions drives
> >the x/y table and the z axis. All axes have ball screws and nuts.
> >Since this machine is a reasonable buy, would it make a device to
> >retrofit for CNC??
> >
> Sure. But don't plan on using the hydraulics. Much better to switch
> over to electric servo drive.
>
> > The hydraulic motors are about the same size and
> >position as servo's driven BP mills I have seen. The motors appear
> >to be driving a pulley/belt rather than direct drive. The z axis is
> >the knee of the machine and not the head. I wounder if servo's would
> >be powerful enough to move the knee up and down (I don't believe that
> >the knee has a counter weight system)
> >
> Sure, a big enough servo would have no problem. But, when you turn it
> off, you need something
> to keep the knee from crashing to the bottom. Big air cylinders or auto
> liftgate gas springs
> would be good for this. A pair of large car gas springs could probably
> be rigged between the base
> and knee to support much of the weight.
>
> > In place of the machine head
> >is a long slotted plate for mounting multiple machine heads.
> >
> This is the "T-Ram". It is a very common option on the duplicators.
> Are you saying there
> is NO machining head at all? They mount to the T-ram with a fixture
> available from
> Bridgeport. But, you may find a servicable J head is more that the
> machine you are
> buying!
>
> Jon