resonance is the sound it makes. I have had a similar issue when i was cutting circles when both axis' wqere moving at the same time it seemed as though when it was going around part of the curve it would slow down greatly then speed up.
Words of Wisdom:
“Words that sink into your ears are whispered…… not yelled”
“The biggest trouble maker you’ll probably ever have to deal with, watches you from the mirror every morn’n”
“The only difference between a rut and a grave is the depth”
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Just remember...when it's time for the hearse to pull up..there's no luggage rack on top!
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The beauty of the Second Amendment is that it will not be needed until they try to take it...Thomas Jefferson