Rotating Ballnut - design ideas

[SafeAirOne]

Plus the price of the bearings. How much they cost? The Chinese bearings we use normally are not very expensive. 10-15$

I was surprised to see the large price range for the exact same bearing, depending on where you shop.

I initially found the bearing on the McMaster-Carr website (which I love because they have free 3D CAD models of most of the products they sell, making design in Solidworks easy). McMaster-Carr wants $48.00USD (45.00EUR/39.00GBP), but a quick search proves that this is a VERY common bearing. It looks like I can find these same bearings/races, manufactured by Timken, for as low as $19.00USD. Perhaps this isn't going to be as hard on the wallet as I originally envisioned.

But thats why i think the roller bearing is not very suitable. It will generate much more heat due to much bigger contact area for friction. I love overbuilding but i believe this is not the place to do that.

I guess this is my question, really: What are the consequences of hot bearings? I imagine the preload will increase due to expansion of the bearing parts, so the bearing life will be reduced (to several million revolutions). Grease life will be reduced (by half for each 10 degrees centegrade of temperature increase!). Other than that, I don't think there will be an impact on machine accuracy or repeatability, unless I'm looking at it wrong.