# Mini Mill Column Stabilizer Arms



## Wireaddict (May 31, 2015)

This is my latest mod to improve the performance of my LMS 3990 Mini Mill.  I added 4-1/2 in. CRS hex rods between the reinforced table top [via 1/4X2X2 in. steel angle] & various places on the column.  The two on the rear of the column are mounted opposite each other in the holes for the original torsion spindle return spring to help reduce twisting & the two on the sides help reduce swaying.  The rod ends are 1/2-20 thread & have left-hand threads on one end so I can simply loosen the lock nuts on the ends & turn the rods one way to lengthen them on both ends or vice-versa. 

I also implemented PetCNC's earlier post about shim-free tramming.  I trammed the column first then adjusted the length of each rod so the rod ends lined up with the mounting holes before fastening them.  I haven't had an opportunity to try it yet but anticipate at least a slight improvement.


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## wrmiller (Jun 1, 2015)

Very nice. 

I planned to do something similar to my PM25 and actually started fabricating the column mounts, then got sidetracked. Mine will attach very near the top of the column and are more to compensate for the weight of the head pulling the column forward.


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## Wireaddict (Jun 22, 2015)

To update my earlier post I had an opportunity to use my Mini Mill after installing the stabilizing arms & found that the vibration was less & the part finish was noticeably better although it still doesn't run as smoothly as the heavier machines I ran as an apprentice over 40 years ago but, IMO, it was worth doing.


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## petcnc (May 5, 2016)

I like your idea! 
I think there is room for improvement on the base support system you apply using wooden blocks. 
You gave me the inspiration to try and make a reinforcing base for the mill that will stiffen the base as well as support the column.
Thanks for the idea!
Petros


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## Baithog (May 5, 2016)

I agree with the comments about the wood. Get rid of it. The whole base should integrate the machine and arms. Get some 10" channel for under the machine. Then weld channel to form a 'T' to integrate the x-axis arms. An 18X24 granite plate or a stack of granite sink cutouts epoxied together. Casting a concrete base with a counter top kit would probably be the cheapest and easiest to do yourself. I'll probably go that route when my CNC project is done. It will never be a 2-ton iron monster, but I think you have a great way of improving the little mill.


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