Bearing question...

[73bronco]

A buddy of mine went to buy some bearings for his Xr10 last night. He wanted the rubber sealed bearings. Well 2 different people he talked to talked him into the metal shielded bearings. Both said that the metal sides(sheilds) help the load capability if the bearing starts to fail. I REALLY have a hard time believing this as the metal shield is very thin. I think there is some salesmanship going on! All the bearings of the same size spec out the same as far as load goes at boca too. SO was he sold a theory or a better bearing??

[dpdsurf]

The only thing I am aware of as far as the difference between metal shield and rubber sealed is that metal shield withstands heat better and rubber does a better job of keeping dirt out. This is why you typically will find metal inside a gear box and rubber in wheels and knuckles.

[Terranaut]

Originally Posted by 73bronco

A buddy of mine went to buy some bearings for his Xr10 last night. He wanted the rubber sealed bearings. Well 2 different people he talked to talked him into the metal shielded bearings. Both said that the metal sides(sheilds) help the load capability if the bearing starts to fail. I REALLY have a hard time believing this as the metal shield is very thin. I think there is some salesmanship going on! All the bearings of the same size spec out the same as far as load goes at boca too. SO was he sold a theory or a better bearing??

I'll say he was sold a fairytale. The metal shield supports no loads whatsoever. It doesn't even make contact with the inner race. And they are very thin, I've pulled many of them out of new bearings. The shield is there to prevent large particles of debris from getting in. Anything small enough to get through is small enough for the bearing to eat without too much harm.

Bearings have a cage inside to keep the balls correctly spaced. Most cheap bearings have a metal cage, but some good bearings have plastic or non-metallic cages, which reduce friction and wear. The metal cages generally let the bearing carry a bit more ultimate load than plastic ones. So I wonder if those salesmen were a bit confused?

Cheers.

[C*H*U*D]

If you are relying on the metal shield to provide support as the bearing fails, you might as well start chasing chickens with bells around your ankles.

Rubber seals contact both the inner and outer race. This provides the best seal.

Metal seals contact only the outer race. They don't seal as well as rubber but roll freer. A good compromise of sealing and performance you could say.

Which one is better? since all the bearings are somewhat protected inside the axles, the metal sides would provide less resistance. At the slower speeds of a crawler, I'm not sure that's a big deal. Since crawlers are off-road beasts and seem to pick up every spec of dust floating around, rubber might be better....the choice is yours.

Make your decision on the sealing properties and rolling resistance you are looking for...not the load capabilities of a dust shield.

[Jeepkid]

The way I see it it, and this is my opinion. Get whatever you want. Avid has both types of bearings on their site and they cost the same. If it is the flange ones he was looking at getting,do metal shield. I did, and you can add a teflon lube to them. Because the metal shield will let the lube soak in. The rubber shield ones would have to sit in a cup of lube for a few hours to penitrate the rubber shield. The metal shields get you up and running quick if you want to lube your bearings. This is my opinion, so dont bash me if I'm wrong. thats how I roll.

[flapjack]

the sheilds are only their to protect the inside....it all comes down to abec rating and material used....

[BEELZEBOB]

if they are just 5X8X2.5 its just a matter of time until those give out too. rubber, metal, ceramic etc.

get the VP bushings, as they are a solid piece of brass that will not break.

or drill out the plate to 9mm

[Jeepkid]

I have the VP's and want to see the difference with bearings. They will be here today, never ran the stock ones. Those hit the trash right out of the package.

[BEELZEBOB]

the only difference i can tell is that the "bearings" fail and spill their guts into the trans.

where as the "bushings" are just a solid chunk of brass with no guts to spill.

[BFGcrawler418]

Originally Posted by BEELZEBOB

the only difference i can tell is that the "bearings" fail and spill their guts into the trans.

where as the "bushings" are just a solid chunk of brass with no guts to spill.

I bought some avids last night but I am kind of leaning torward going with the VP bushings just because the fact that a bushing will wear over time and would be less prone to breaking like a bearing.

If the bearing was of a larger size I would not be too worried about this but since they are soo small it is prone to just breaking and taking out the gears. Atleast if the bushings wear I can visually inspect them every so often & regrease.

[BEELZEBOB]

Originally Posted by BFGcrawler418

I bought some avids last night but I am kind of leaning torward going with the VP bushings just because the fact that a bushing will wear over time and would be less prone to breaking like a bearing.

If the bearing was of a larger size I would not be too worried about this but since they are soo small it is prone to just breaking and taking out the gears. Atleast if the bushings wear I can visually inspect them every so often & regrease.

I have the VP bushings in the front axel only. and rubber Avids in the rear.

I will let everyone know when the ass breaks, as i have spare AX30556,AXI30554 and AX30155 at home.

i will order more bushings, or do the 9mm mod this weekend, depending on what my girlfriend wants to do.

LOL she has been very good about waking up early to go fly planes, and then driving all over Colorado to attend comps with me every weekend.

so i may actually let her choose the activities this weekend.

and if we're really busy, ill just order more bushings.

[motorman]

Originally Posted by C*H*U*D

If you are relying on the metal shield to provide support as the bearing fails, you might as well start chasing chickens with bells around your ankles.

Rubber seals contact both the inner and outer race. This provides the best seal.

Metal seals contact only the outer race. They don't seal as well as rubber but roll freer. A good compromise of sealing and performance you could say.

Which one is better? since all the bearings are somewhat protected inside the axles, the metal sides would provide less resistance. At the slower speeds of a crawler, I'm not sure that's a big deal. Since crawlers are off-road beasts and seem to pick up every spec of dust floating around, rubber might be better....the choice is yours.

Make your decision on the sealing properties and rolling resistance you are looking for...not the load capabilities of a dust shield.

bells around the ankles??? thats funny!

and just to add to that, sealed bearings have a lower speed limit than shielded bearings. It might not affect the world of RC'ing, but it's true. I would recommend sealed bearings anyway.

edit:oh, and about the load thing, I don't know what company that was but I'd stay away from them, they have no idea what their talking about.
unless it was an Acer chick