Bearing and Rod Size Help Needed

rymass

Hi Everyone,

I'm designing a small drone in CAD but have stumbled upon an issue I just cant seem to work. It's simple, but for some reason I cant get it right.

So, I have a bearing that has an inner diameter of 10mm. I have a carbon fiber rod with an outer diameter of 10mm. Will the rod fit through the bearing, albeit, a tight fit? Or do I need to get a smaller rod, like 9mm? In CAD it fits just fine but I need to know if these sizes will fit in real life.

It also has to be a tight fit because the rod cant jiggle about whilst inside the bearing.

Thanks,
Ryan

CatFromHue

try and find out the exact specs and tolerances

a 9mm rod would be too loose for what you want i'd say but when you look into the details you could be looking at a hole of 10.2 and a rod of 9.8 for example

PrzemoF

There is a whole science & standards behind it. It's never 10 mm. It's 10.01, or 9.98, or 10.001. It's called interference fit (I'm open to correction here). A starting point for you: http://tribology-abc.com/calculators/e3_8.htm and tolerance table translated (with errors) from Polish: https://translate.google.com/translate?sl=pl&tl=en&js=y&prev=_t&hl=en&ie=UTF-8&u=http%3A%2F%2Flwcad.republika.pl%2Ftolerpas%2Fr_pas_st_otw_h7.htm&edit-text=

Detailed info about bearings: http://www.skf.com/uk/products/bearings-units-housings/ball-bearings/principles/design-considerations/radial-location-bearings/recommended-fits/index.html

Turbulent Bill

Google shaft and hole limits and fits for how to do this. In short, precision shafts, bearings etc. are made in a range of tightly-toleranced diameters, and you combine these to suit your application.

rymass

Thanks for the info everyone!!! Much appreciated.

rymass

Thanks for the info everyone!!! Much appreciated.