Dear All,
I ordered and then installed the extended column. Wow, what a difference it makes when trying to do drilling or work with setups that have an angle table or angle table+rotary table+chuck, etc.
I also found out that my old standard column wasn't working right. Any time I used the z lock, the head would move down 3-4 thou. I also had around 6 thou backlash. Nothing I did made it better. This is my first mill, and I am learning milling from books, forums, youtube, etc. So, I assumed that I was doing something wrong.
After I ordered my new column I called Sherline to talk about this problem and what I could do with the new column to ameliorate it. I spoke with Fred, and he said "...that sounds wrong". So he assembled a new extended column with a new saddle and sent that to me.
The new saddle makes a huge difference in z-axis accuracy and, most importantly, precision. I can now lock the saddle with no saddle movement. I also now have 3.5 thou of backlash. I am a very happy customer. BTW, the new saddle and assembly of the column did not cost me anything. My machine is less than a year old.
I mention the above in case anyone else is having z-axis gremlins like mine, and don't know any better.
I sent my old column + saddle back for inspection. I told them I don't really want the old column back, even if they can fix it. However, if anyone here would like it, I can have Fred ship it back to me and then ship it out to you. Just let me know.
Thank you again for all your help.