Re: [CAD_CAM_EDM_DRO] Motors moving so fast with Mach2 - stuck Z axis up too far

Keith Clark wrote:

>A bad thing happened just now... My Bridgeport with dead Boss 6
>control) mill just retracted the quill up past the upper limit
>switch and is stuck. I am in the process of trying to retrofit it
>with a new controller when I got the motors going so fast with the
>new Mach2 that it retracted too far before I could stop it.
>Unfortunately I am still in the process of getting the limit
>switches to work. All I can say is @#%^%$@&$^!
>
>I am afraid the ball and quill extension mechanism may be ruined.
>Does anyone have any advice as to how to ease it back into working
>order or shall I call my local repair dealer for a new mechanism...
>
>thanks
>Keith Clark
>
>
>

I use a bar of soft metal (brass or alum) and a hammer. Stick the
bar into the teeth of the large
pulley around the screw at the front side of the pulley and give it a
few taps. Depending on how hard
the screw was driven past the limits, determines how hard these taps
have to be. That thing can stick
really tight as the pulley runs itself down on the screws that hold the
ball screw to the top of the quill. I don't
have much problem after retrofit but the original control obviously did
based on the condition of the pulley
when I took it all apart. The previous owners apparently had only large
screwdrivers with which to
perform this task...
Larry..