Bridgeport CNC with Masso Controller/Clearpath

This is going to be my first CNC build and my First build log. I've decided that a build log on this forum might be a good idea for this project so the next guy to take on this project doesn't have to deal with the stupid stuff I'm already running into.

This is my Masso Controller
I will be using 3 Clearpath Stepper Killer servos model# CPM-SDSK-3432S-RLN
They are a little over 6" long...
almost 3.5"
1/2" shaft with a 3/16" keyway
I will be using Teknic's IPC-5 75VDC power supply
But before you can wire up you Masso controller you have to power up the Clearpath servos and plug them in to a PC with the ClearPath USB-B cable and it absolutely has to be their cable I've already tried 5 others, now I'm waiting for UPS to deliver a "Teknic Certified" USB cable. Very Lame....
Their program will not see my servos without the "Teknic Certified" USB cable...

Edit: Almost any USB cable will work.... lol
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Yes, plunging center cutting end mill.
X axis was parallel with the round stock...
Y axis parallel with the slots....

Maybe I should have left radial stock and came back with a 2d contour to clean up?
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Then that might explain it. Maybe the end mill was walking around at the top of the cut, and was running straight by the bottom of the cut. I have seen that happen. A spiral down cut might have worked better.
Tool flex? What size end mill and depth of cut through the part?

I recently ran a routine with a complete doc of 1.2" using a hss 1/4" deep cut end mill and had 0.020" difference on the top vs. bottom. Ended up doing a couple of spring passes to get it pretty close.

Wow, can't imagine flexing carbide, definitely not that. I'm at a loss as I can't imagine an end mill orbiting like a "V" in the spindle so it's making a larger cut by 0.010" on the opposite side. Curious what you end up figuring out!

What happens if you do a profiling cut? Maybe try a flat piece of flat stock and go to the depth of your round stock. Measure the width at the top and bottom?

I have never had much luck trying to mak a slot the same size as the end mill. It will find every bit of backlash and slop in the spindle bearings and any other play in the whole setup and add it all together for worst case.
Even center cutting end mills do not like to do a deep plunge, even when done in steps. I have had much better luck predrilling a hole at the point of the plunge that is enough to clear the web of the mill.
Anyone have any ideas how to stop this madness.....? My VFD throws an error every time the spindle stops and I have to power cycle the VFD to get it to run again.... its getting fairly annoying......

this is message number 1,000!
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Doing a few engraving test cuts.... Using a 1/8" 60° single flute Solid carbide D cutter.... I had to sacrifice 2 of them to the CNC Gods to get it cutting properly.....
This OP really shows me that I need to adjust the backlash on my X axis.... BUT it could also be this free website i was using to convert picture fIles to SVG files.... I'll try making text completely in fusion 360 before making any changes.....
You guys know that really cool sign that we all want but are to cheap to pay
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