Ball bearing grades in rc?

[Losi_110]

As the title, does anyone have any idea as to how good a grade of bearing is used in rc? I'd hope pretty good for the prices we have to pay but just wondering. Ta.

[bretts]

I find rcbearings to have all what I need, they do ABEC 5 Bearings which sounds like a quality rating and also ceramic if you've got the cash.

Also, AnswerRC do some SP bearings which seem very good, and MB do some Balls Out bearings which I've heard good things about too.

Avoid ebay china specials, i suppose.

[HOTSHOT III]

https://en.wikipedia.org/wiki/ABEC_scale

[fidspeed]

I use RC bearings and find them fine delivery is swift (check their website )
99% bearings fit a "standardized" sizing spec

as with anything "miniature" production costs tend to rise because of tooling costs as normal far eastern versions are cheaper because of cheaper production costs and they don't have quite the stringent quality checks and gurantees that the rest of the world generally adhere too

regards dave

[CHEVY]

I have used pbi bearings in Kent for bearings

[Welshy40]

Acer bearings are also good online, ceramic make a huge difference. Also if getting ceramic balls for your diff get carbide for the thrust balls.

[Col]

Personally, I don't think the quality of the bearing makes much difference. What matters to me is the sheilds ability to keep debris out.

[Aire valley]

https://en.wikipedia.org/wiki/ABEC_scale

I like that.....:thumbsup:

[SlowOne]

By and large the ABEC rating isn't that relevant to our application. It's best to aim for something like 3 or 5, but above that you are paying for something you won't use because...

The walls of the races we use are thin and easily deformed. Bearings should have a controlled interference fit for the shaft and housing so that, when assembled, the gap between the balls and the races is closed so there is no play and no pressure.

Both the housings and axles we use are not well-enough controlled. When a bearing is fitted it is just as likely to expand/contract the races so that there is an interference or a clearance, neither of which is good for bearing life or performance.

Most bearings are made with high rotating speeds in mind which we never reach. Our application should be with high axial loads in mind, but they aren't. And composite bearing cages are less susceptible to high axial loads than metal ones - which is what all our bearings have!

An ABEC 7 bearing in a poorly fitting housing will be as likely to fail as an ABEC 3 bearing in the same housing. The tolerances are not sufficiently different to make any difference to performance in our application, it is all down to the fit in the housing/on the axle. ABEC tolerances on OD and ID vary by about 0.001" across the range of ABEC numbers, whereas the tolerances of our parts will be around .002" (metal) to about 0.010" (plastic), so the impact of a tight fit of a bearing into a housing is way more than the tolerances of the race diameters or the their eccentricity.

For our applications the key things are to get rid of the grease inside the bearing and use a decent synthetic oil - bike chain oil or Mobil 1 are best - and make sure that there are no tight fits in the housing or on the axle. Then make sure you use the best seals that you can to keep the dirt out. One bit of grit or sand in the bearing and your expensive purchase will be bin fodder.

It's your money, you choose. Just don't imagine that an ABEC 5 or 7 bearing will give you any more performance or life than an ABEC 3 in our applications - it won't. HTH :)

[Origineelreclamebord]

I'm no bearing expert, but I do know that tolerances are only part of the story: Things like materials & grades, lubrication and shielding are easily overlooked :) They'll affect roll resistance, suitability for high loads, high RPM, impacts, sensitivity to dirt/moisture, maintenance requirements, etc...

I mostly just run the standard stuff from the kit and it's usually been ok :)

[bodgit]

Brings back memories.
http://www.oople.com/forums/showthread.php?t=80289

[Losi_110]

Hi guys, I should of got back on this a bit sooner as I don't think I have been very clear as to what it was I was asking.
When I asked about ball bearings I didn't mean shaft bearings but diff ball bearings as from grade 3-1000 there seems a rather large difference, but I've never put much thought as to how good they actually are, I've just bought the packs on offer and gone from there.
Cheers guys

[mattr]

Scrub that, just realised you meant ball diff stuff.