Hi all, I'm currently building a sphinx style machine. I used my modified x-carve to make the plates and its coming along nicely, however the mini v-wheels are causing me grief. Originally I purchased some through aliexpress, big tree was the brand I believe. They spin nicely until they're on the machine.. I found that if I was tightening a bolt to the point it felt nice and sturdy, the wheel would no longer spin freely, and if i tightened so the wheel spun freely, there was play in the bolt.. I figured i'd replace the wheels with openbuilds wheels instead. While they perform better, at least half aren't great and 3-4 grind. I was careful not to overtighten them so I don't undertand what's happening. Is it just a bad batch of bearings? FWIW: both brands had a spacer between bearings so that doesn't seem to be the issue. Thanks in advance!
The the outer circle is not on the same axis as the bearing, it will bind. That's equivalent to being out of round.
Did you put the extra shim between the wheel and the spacer? Mini V-wheels need an extra spacer to be in alignment with the larger V-wheels. Also, the eccentrics don't need to be tightened beyond the point that the wheels don't slip easily. Put a finger on a tightened wheel and try to spin it. If you can get it to slip with moderate pressure, it's good. If you can't, it's too tight. If it spins freely, it is too loose.
when assembling the wheels, i like to take a smooth flat scrap of plywood or MDF and use it as a press (with the table and my hand) to make sure the bearings are seated all the way. It can take a good amount of force to make them fully seated, make sure the washer is centered. That and the extra 1mm shim Rick said..
Thanks for the replies guys. I did put the extra shim after the spacer yes. The 'binding' is happening even when not on the c-beam. I contacted the makerstore who told me i needed to use 2 spacers. This makes them spin nicely, but means I don't have enough clearance, I found some low profile nylock nuts I may have to look into..
