I seem to have some slop/lash/variance in the X axis of my mini mill. Since
I mostly use it for engraving it was not horrible, and I never really
worried about it, but occassionally I machine a part that needs to be
consistent. Also, recently I was doing some circle cutting in the process
of making some commemorative coinds for an event, and I noticed they had a
distinctive off center bump near the extemes of travel on the x axis. Very
visible. I could deal witgh a few thousands out of round, but this is a
visible distrotion of the shape of the coin. How do I adjust the mill to
reduce this problem?

"Bob La Londe" wrote:

I seem to have some slop/lash/variance in the X axis of my mini mill. Since
I mostly use it for engraving it was not horrible, and I never really
worried about it, but occassionally I machine a part that needs to be
consistent. Also, recently I was doing some circle cutting in the process
of making some commemorative coinds for an event, and I noticed they had a
distinctive off center bump near the extemes of travel on the x axis. Very
visible. I could deal witgh a few thousands out of round, but this is a
visible distrotion of the shape of the coin. How do I adjust the mill to
reduce this problem?


Is this a Taig that started out as a manual one? Looking at the website, they make a cnc
ready model that has adjustable leadscrew nuts.


If the first case, you might want to contact them for purchase a retrofit nut.

Googling around I got this:

Feed nuts

The standard feed nuts on the manual mills, and on the earlier CNC mills, were plain Brass
or Bronze nuts with no adjustment for wear; later CNC mills had nuts that allowed
adjustment to take up wear (a longitudinal slit along the nut and a clamping screw that
allowed the nut diameter to be reduced). These adjustable nuts can be obtained from Taig
in the USA or Peatol in the UK if you want to further reduce the leadscrew backlash. If
you plan to fit these nuts it is worthwhile to take some time while the mill is
disassembled to adjust the clamping screws for minimum backlash on the leadscrews.
Obviously, as any wear on the leadscrew is going to be in the middle of the range of
travel, this is going to be a compromise between backlash reduction in the middle and
freedom of movement at the ends.


HTH,

Wes

"Wes" wrote in message
...
"Bob La Londe" wrote:

I seem to have some slop/lash/variance in the X axis of my mini mill.
Since
I mostly use it for engraving it was not horrible, and I never really
worried about it, but occassionally I machine a part that needs to be
consistent. Also, recently I was doing some circle cutting in the process
of making some commemorative coinds for an event, and I noticed they had a
distinctive off center bump near the extemes of travel on the x axis.
Very
visible. I could deal witgh a few thousands out of round, but this is a
visible distrotion of the shape of the coin. How do I adjust the mill to
reduce this problem?


Is this a Taig that started out as a manual one? Looking at the website,
they make a cnc
ready model that has adjustable leadscrew nuts.


If the first case, you might want to contact them for purchase a retrofit
nut.

Googling around I got this:

Feed nuts

The standard feed nuts on the manual mills, and on the earlier CNC mills,
were plain Brass
or Bronze nuts with no adjustment for wear; later CNC mills had nuts that
allowed
adjustment to take up wear (a longitudinal slit along the nut and a
clamping screw that
allowed the nut diameter to be reduced). These adjustable nuts can be
obtained from Taig
in the USA or Peatol in the UK if you want to further reduce the leadscrew
backlash. If
you plan to fit these nuts it is worthwhile to take some time while the
mill is
disassembled to adjust the clamping screws for minimum backlash on the
leadscrews.
Obviously, as any wear on the leadscrew is going to be in the middle of
the range of
travel, this is going to be a compromise between backlash reduction in the
middle and
freedom of movement at the ends.

This one is a CNC mill with an adjustable nut. Somebody sent me a link to a
page that shows how to adjust it. I adjusted the X-axis last night and its
better, but it still shows the bump and flat spot, so I'll adjust the Y-axis
today sometime, and then try it again. If that still doesn't work I'll pop
off the steppers and take some measurements manually to see what I get
compared to what my software produces. I have already concluded due to
other issues that I need to save Mach3/Lazycam for the simplest non-critical
things and figure out how to get my EMC working with this controller.

On Fri, 17 Apr 2009 08:35:09 -0700, "Bob La Londe"
wrote:

This one is a CNC mill with an adjustable nut. Somebody sent me a link to a
page that shows how to adjust it. I adjusted the X-axis last night and its
better, but it still shows the bump and flat spot, so I'll adjust the Y-axis
today sometime, and then try it again. If that still doesn't work I'll pop
off the steppers and take some measurements manually to see what I get
compared to what my software produces. I have already concluded due to
other issues that I need to save Mach3/Lazycam for the simplest non-critical
things and figure out how to get my EMC working with this controller.

Sounds like upgrading to a ball screw is what you need.

Wes