Spool enhancment.
thingiverse
I just hung my spools on the rod of my k8200 as most people do, initially at least. It rattled a bit and jerked, which I'm sure isn't great for accuracy. I picked up bearings for pennies from a company in the Far East, http://www.amazon.co.uk/gp/product/B0056EVJX2?psc=1&redirect=true&ref_=oh_aui_detailpage_o01_s00, a 3mm ID would be better but that doesn't matter here. Now it rolls smoothly. Plus now I have an extra penny washer and lock nut. Instructions When made, sand/file the bearing space. Put the bearings in the freezer, heat the part to a 100 degree Celsius and after a few minutes it'll be ready for a press fit using a vice or bearing puller. Same with the nut handle.
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