Did my alignment test on the z tonight. I’m out 2½ thousandth. I’d like to get it a little better than that. According to the calculator and my test cards I needed three shims in the lower position. Question is do I take it apart and pull two of them out or would you just add two to the upper locations?
There’s not much to take apart. Just take out the three 5/16 cap screws, slide the lower carriage over, remove the shims, and then slide it back into position. Should just take a few minutes.
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OK sounds good thanks! Never thought about sliding the bearings over😂. Must be tired!
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Hello, I’m in the process of adjusting my z-axis, but whether I add shims or take shims away I see very little change on my dial indicator. Currently there is approx .005" misalignment.
Any advice would be appreciated.
I had a similar issue with adjusting the nod. When assembling, the LS shim calculator called for 3 shims on the bottom bearing blocks. After a few projects, I decided to fine tune the nod and tilt. The nod was leaning back by a few thou so I added shim(s) to the top bearing blocks to try and even it out, I was avoiding pulling the shims from the bottom, but I added up to a stack of 3 shims with almost no change.
I ended up pulling all the shims from the bottom and still had a lean back on the nod. I examined the shims from the bottom and there were screw indentations on the inboard upper corner of each shim stack. These lined up with the bottom screws to the linear Z-Axis rails. Apparently the screws were too long and impacting the bottom bearing blocks. I ended up removing the screws and grinding them down a bit.
Even after all that, the nod was much better, but still had a slight lean back. I had to put a couple of shims on the upper bearing blocks. I think my deviation tag(s) may have been mismarked as negative instead of positive.
Not sure of your exact issue, but that was my experience. Sorry for the long story.
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Hello, thanks for the response. Yes, I noticed the indention in the shim as well. I will take a look. Hopefully that will resolve my issue, because currently nothing changes when I add or remove shims. 
Those super fine shims for the Z axis were pretty much useless for me. I used leftover Y Axis shims. One course, one fine, and one or two of the ultra fine Z axis shims got me to 0.000 from 0.011.
One Y axis shim can be cut into two Z axis shims with tin snips.
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Thank so much for the tip. Sounds like a great idea. Will give this a try as well.