Cut open a toilet paper tube. Wrap it *snugly* around a sewing machine bobbin to measure the amount of paper tube needed, butt the edges and cut to fit. Tape the seam with masking tape.
I tried both three, and four and a half inch long tubes. Three inches worked better because there was less wobble as it wound on the Sidewinder. The pictures below show the four and a half inch tube.
Hold the yarn end on the tube until the first few wraps hold it in place. I wind straight to the tube and by pass the Sidewinder's tension because the yarn's too thick.
The four and a half inch long tube wobbled a LOT, so I balanced it with my thumb. Press the green power button in short bursts and manually disperse the yarn along the tube.
Two things to keep in mind: Don't wind any yarn down at the base of the tube and make sure the keeper - see arrow in photo - is all the way to the left, otherwise it will shut off the winder.
Continue to wind slowly by pushing the power in short bursts. After about 3/4 of the way along, I took it off and wound the rest by hand. The ball above is on a three inch tube and looks smooth because I finished with hand winding. -- I probably won't do too much of this; the Sidewinder cost over 20.00. I don't want to burn it out!