Thread: took the plunge
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Old 03-23-2008, 11:28 AM
bilinghm bilinghm is offline
 
Join Date: Mar 2007
Location: usa
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I redid the test. First, I moved the indicator up to 17.5” above the table. I clamped the mill base to the table with a huge C clamp.

Without the brace, placing the palm of my hand against the top of the column and pushing HARD, the column deflected .008. In fact, the column would deflect .002 with thumb pressure.

With the brace, pushing equally hard, the column deflected .0015.

Certainly not a scientific test, but highly repeatable. Conclusion, A brace, even of flawed design and inappropriate material selection, is highly effective in reducing Y axis flex.



Originally Posted by mrcodewiz View Post
.001? I put my Z as high as it would go and put a dial indicator from the spindle referenced against an angle plate on the bed and using a modest amount of effort pulling on the head, I can get up to .005 deflection. I can see deflection of .0005 just adjusting the Z height with the handwheel. I have replaced the mounting bolts with hardened bolts and have torqued them all equally - I guess what I am saying is that I'm suprised you are only getting .001 without the brace - of course maybe it is because you only tested 6" up? Do you have any idea what you torqued the mounting bolts to?
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