Why aren't more people using Adam's Full Ceramic bearings?

[FlailingLlama]

They are slightly cheaper than Bones Swiss Ceramics, but they are full ceramic, Silicone Nitride inner, and outer race, and balls.

Unless they are super low tolerance, wouldn't these bearings be the absolute best?

Thanks

[ursle]

Silicon Nitride balls are great, races not so much and the expense, bones have replacement parts.

[FlailingLlama]

Originally Posted by ursle

Silicon Nitride balls are great, races not so much and the expense, bones have replacement parts.

What makes the races not a good idea? Would a more crack resistant ceramic be better for the races?

[Mort]

Originally Posted by FlailingLlama

What makes the races not a good idea? Would a more crack resistant ceramic be better for the races?

Ceramics are mostly a gimmick. I have never seen a load test that displays any significant advantages in running torque.

Ceramic may be hard, but it's also brittle, and can fracture.

People think that they are some great idea to use and do not understand why they exist in the first place.

[zebra1922]

Originally Posted by Mort

Ceramics are mostly a gimmick. I have never seen a load test that displays any significant advantages in running torque.

Ceramic may be hard, but it's also brittle, and can fracture.

People think that they are some great idea to use and do not understand why they exist in the first place.

Genuine question, why do they exist? I know little about bearings apart from the ABEC rating not necessarily being a good measure for skating quality.

What problem is ceramic trying to solve? Does it help skaters?

[ursle]

Originally Posted by zebra1922

Genuine question, why do they exist? I know little about bearings apart from the ABEC rating not necessarily being a good measure for skating quality.

What problem is ceramic trying to solve? Does it help skaters?

Bones ceramics last forever, the balls anyway, parts are available from bones, and they're silent or whisper quiet, and if you skate outdoors, you don't have to worry about water, steel bearings will rust up a few minutes after getting wet, while you're skating.

Full ceramics are pricey and as mort mentioned, the races are brittle, half the performance is the speed creme bones sells, 2-3 drops per bearing after cleaning and rinsing with 92% isopropyl and zoom.

[Mort]

Originally Posted by zebra1922

Genuine question, why do they exist? I know little about bearings apart from the ABEC rating not necessarily being a good measure for skating quality.

What problem is ceramic trying to solve? Does it help skaters?

Ceramic doesnt solve any problems for skaters. It creates them

Ceramic bearings exist because some environmental conditions prevent metals from being used, or because corrosive conditions dont offer long service life.

Bones speed cream is nothing more than over priced clipper oil, and it's totally snake oil, IMO. There are NO testing results that prove otherwise. No lubricity testing nothing.

There is virtually nothing more slippery than today's synthetic engine oils. Which are(usually) around 5 to 9$ a QUART. You tell me how one can justify charging the same price for HALF A FLUID OUNCE.

https://bonesbearings.com/bonesr-speed-creamr-lubricant

Say it with me, snake.. oil...


ABEC ratings cover dimensional accuracy. The higher the rating the more "perfect" to the spec the bearing calls for.

While many companies will have better raceway specs, and more spherical balls, along with better runout, the higher numbers are typically for bearings that need extreme accuracy such as a cnc machine which will be attempting to manufacture parts to an accuracy of .0001" these bearings usually have tighter internal clearances and thus no radial and axial play, they generate more heat too.

If you actually get an "abec 9" bearing, it would be expensive.

For refrence, an Italy made SKF EMQ(Electric Motor Quality) ABEC3 C2(tighter than standard clearance) bearing is about 20 bucks from a parts retailer.

the thing is , many bearing will fall around the ABEC3 scale just from being made on equipment that can make ABEC9 precision parts. Also, nearly no one out there has the equipment sophisticated enough to disprove those ratings. Most are pure BS.

Would ABEC rating matter? I dont know.

You would have to find 2 sets of bearings, made to the exact same internal clearances, use the same cages, use the same lube, the "ABEC1" would need to fail being any better than its minimal specs, meaning it could only be able to pass as an ABEC1, not 3, and the "ABEC9" set would need to be legit in its precision to truely compare them.

Even then, skating it would likely not tell ya anything, and a sophisticated machine would be needed to test the starting and running torque of those bearings to see any difference.

Wheels make a much larger influence. Good quality high rebound urethane will feel faster than low quality urethane which has less liveliness to it.

Crude example would be a Jax pink ball vs a super high bounce ball.

Urethane also has a lifespan, and it only gets worse the more it's used. Inline skates are a perfect example. The exact same set of wheels will perform differently after 100 miles is put on them due to depreciation of characteristics. Same thing with a brand new tennis ball vs one that's been beaten on for 12 hours of tennis.

[ursle]

There's no grey area concerning Bones Speed Creme, it solidifies when cool and turns back into a liquid when it warms, perfect for skate bearings, synthetic oil simply drips out of the bearing, then it's an unlubricated bearing, you might as well use grease rather than straight synthetic, the grease will be there after thousands of hours, slow, but the wheels will go.

Ceramic balls are perfect for skate bearings, they never wear out, they don't rust, at some point one must consult their common sense.

[Mort]

Originally Posted by ursle

There's no grey area concerning Bones Speed Creme, it solidifies when cool and turns back into a liquid when it warms, perfect for skate bearings, synthetic oil simply drips out of the bearing, then it's an unlubricated bearing, you might as well use grease rather than straight synthetic, the grease will be there after thousands of hours, slow, but the wheels will go.

Ceramic balls are perfect for skate bearings, they never wear out, they don't rust, at some point one must consult their common sense.

Common sense indeed... which you don't seem to have...

Ceramic does not like NVH, which includes slides, ya know like plows, T stops, hockey stops, jumping or other impacts, cracks in sidewalks etc, and its failure rate is higher than steel, significantly. If someone only skates softly, and wants to not have any thought that they have any potential waste in the maximum roll, then they could speand a lot of money chasing 1% or less.

For the cost of those way overpriced bones swiss ceramics, I could get another set of the best wheels on earth, made by Scott Corey, in any color or hardness I want. Ya know, something that actually matters.

Oh, and speed cream, I have a bottle at my house someone gave me, brand new from the rink, won it as a prize, it's never close to a solid, its clipper oil, Its thickness is about that, feels gritty in comparison to even non synthetic engine oil. Why? Because it lacks good refinement of quality lubricants.

I mean. If you have test specs from a lubricity tester, I'd love to see the video, the wear scar produced, etc. I'll be happy to send my bottle off, it will never get used up. Maybe on my beard trimmer, as that's all it's good for.

Funny you say synthetic will drip out when others, myself included, have no problems with it 🤔 . Using oil, one should relube every 20 hours of use or so, too much free spin is a clear sign the bearings are dry.

Also the cages used in bearings will influence lubrication life. Phenolic retainers found in most skate bearings holds onto oils, so it doesnt just "drip out". That combined with 2RS, non contact seals, and you have a winning combination. The outer race is sealed and the inner is non contact, containing the lubricants. Even when being aerosolized from high vibrations included during stopping maneuvers.

There are skaters with 30+ years of use on FAFNIR bearings, steel balls. I doubt a ceramic will last that long under skating abuse.

Take the gamble, I wont.

[BigFoot]

…nothing better than a good bearing discussion, I say. Always been a hot topic in SLF. And prolly as old as skating itself. I love it.

First, I want to thank FlailingLlama for alerting us, or at least me, to the big price drop of a full-ceramic skate bearing. I knew it would happen. It just took longer than I expected. It has been 35 years since they were invented and finally the price is competitive with a top rated steel bearing.

I am a supporter of full-ceramic bearings. (Some might call me an athletic supporter, haha.) But I see them as the future of skate bearings. The main reason is they roll better. The contact points - balls and races - are smoother than steel and therefore they create less friction and micro vibration. I have read claims of 10%, 20%, even 30% less friction. Whatever the true percentage, no one disputes their lower resistance or drag. You can see the reason for this by looking at a side-by-side magnification of their surfaces. The ceramic surface looks much smoother.

They are also harder and last longer. One claim I have read is a 50% reduction in wear rate. I don’ts doubt this percentage because of my personal experience with long-wearing ceramic/steel hybrid bearings.

For what it’s worth, for the last 14 months I have been running full-ceramic bearings on my right front axel. They were expensive, but I wanted to test them for susceptibility to cracking/failure before I spent the big bucks for all 16 bearings. So far, no problems. The full-ceramic bearings are silky smooth. When I rock back and forth between axles, it is noticeable. They feel nicer than the hybrid, and much better than steel bearings. No, I don’t have “sensitive feet” and it’s not a delusion, the silky feeling is real.

[Mort]

Are they radially and axially tight? Which would be to keep shock lower. But would add drag/friction. Are they sealed or shielded in any way?

If they are HIP type their hardness and fracture resistance is better than GPS.

Not sure what grade or manufacturing process the balls that WIB uses for the ceramics produced for bones.

What duro wheels do you use and where do you skate?


The worst thing we do to quad skate bearings is hockey stopping. Ironically, the bad abuse to the bearings comes from indoor use. Harder wheels, hard floors, lateral loading , and lots of NVH.

[ursle]

Originally Posted by Mort

Common sense indeed... which you don't seem to have...

Ceramic does not like NVH, which includes slides, ya know like plows, T stops, hockey stops, jumping or other impacts, cracks in sidewalks etc, and its failure rate is higher than steel, significantly. If someone only skates softly, and wants to not have any thought that they have any potential waste in the maximum roll, then they could spe()nd a lot of money chasing 1% or less.

In your opinion, which honestly Trom, doesn't include a fact, or a fact hidden by misunderstanding.

If you don't want ceramics don't buy them, but stop the stupid, others shouldn't be influenced by your prejudice, (preconceived opinion that is not based on reason or actual experience)


For the cost of those way overpriced bones swiss ceramics, I could get another set of the best wheels on earth, made by Scott Corey, in any color or hardness I want. Ya know, something that actually matters.

The Wheels will wear out quickly The bearings will last forever, it's your money to waste.


Oh, and speed cream, I have a bottle at my house someone gave me, brand new from the rink, won it as a prize, it's never close to a solid, its clipper oil, Its thickness is about that, feels gritty in comparison to even non synthetic engine oil. Why? Because it lacks good refinement of quality lubricants.

I mean. If you have test specs from a lubricity tester, I'd love to see the video, the wear scar produced, etc. I'll be happy to send my bottle off, it will never get used up. Maybe on my beard trimmer, as that's all it's good for.

Funny you say synthetic will drip out when others, myself included, have no problems with it �� . Using oil, one should relube every 20 hours of use or so, too much free spin is a clear sign the bearings are dry.

Well, on your say so... I took the oil pan off my 2019 Rav4 Hybrid and lo and behold, 2 minutes later the engine seized, I don't think I believe that synthetic oil stays in place and doesn't get flung by centrifugal force or drip to earth with gravity, but if on Eart2 it works for you, don't wake up, you'll be disappointed.


Also the cages used in bearings will influence lubrication life. Phenolic retainers found in most skate bearings holds onto oils, so it doesn(')t just "drip out". That combined with 2RS, non contact seals, and you have a winning combination. The outer race is sealed and the inner is non contact, containing the lubricants. Even when being aerosolized from high vibrations included during stopping maneuvers.

Right, it only takes 20 days before a relube, which actually would be necessary per use, which points out the beauty of speed creme, it solidifies into a wax, then it warms up into an oil, it's not magic it's science, magic on the other hand won't keep the synthetic oil on the bearings, but if one uses bones speed creme, there's no magic, it's science.


There are skaters with 30+ years of use on FAFNIR bearings, steel balls. I doubt a ceramic will last that long under skating abuse.

Take the gamble, I won(')t.

Your doubts are as valid as using two thick pair of cotton socks to skate because your boots are to large, or mounting skate plates opposite to the correct way, the way that provides balance and makes skating easy and pleasurable.

Ceramic balls last forever, steel rusts.



Anyway, Trom aside.

I use steel races and ceramic balls, just like I drive a Hybrid car, I love the electric but don't want to be limited to 200 miles between charges, and 1/3 of that in the cold, I'm jonesing for full electric, but it's not ready.
I'd love a full ceramic, a mini full ceramic would be the bee's knees, combine Roll-line Heliums with ceramic mini bearings, I'd buy.

Wonder what they would weigh?

Need more input about the full ceramics and Bigfoot makes a great point.

My apologies to the op for the drama, but, one of the best skate products is speed creme and another is bones ceramic bearings, a third is roll-line wheels), letting someone confuse reality for whatever reason is detrimental to skating, nobody wants to suffer a fool, and the skatelog certainly is in the sights of one.

Again, everyone needs to use their common sense, yes, bearing discussions are the gravy of skating, if you want performance, look at present day racing, skateboard downhillers all use ceramic bearings and speed creme, artistic skaters use what their coach taught them to use, and their coach was taught by their coach and the learning goes back to seperate ball bearings, 100 year old technology.

Roller speed skaters I hope use the fastest bearings, but, they were coached and need to upgrade from steel, hopefully they do.

[FlailingLlama]

If it makes any difference, I talked to Adam for while, and he doesn't recommend his full ceramics for big jumps, parks, or aggressive moves.

He recommends oiling the bearings like normal, this extends service intervals because it slows the progression of debris into the races, although if you indoor speed skate, you don't oil them at all. (just clean as needed)

I'm still curious, though, if we are all thinking of ceramic in an old way, like the very first ceramic break rotors, or other things that were quite brittle, and susceptible to nvh.

It would be nice to have some torture testing done, not just on the ceramic balls (which when made properly, are significantly stronger under impacts) but the races too, and under bumpy lateral loads. I would imagine the overall design of the bearing rather than its material would contribute to toughness.

I've just opened up Bones' nicest bearings to take a look (Super Swiss 6, and Swiss Ceramics) and while the overall design of the Swiss Ceramic is nothing special (compared to other very cheap bearings I've opened) The Super Swiss 6 has remarkably deep and wide (twice as wide as 7 ball channels), inner and outer race channels for the balls to roll in.

Without any testing done, its seems like these deep channels would hold up to substantially higher lateral loads and abuse. Larger balls (they are HEAVY especially compared to the 5/32" ceramic balls) also help spread loads over more surface area.

I wouldn't think a 6 ball full ceramic is a good idea, because of the thinner race material due to the deeper channels, but a hybrid (steel inner and outer race) with 6 Silicon Nidride balls should be an excellent bearing.

Not so much because of rolling resistance, which in my remedial tests, the Silicone Nitride balls make zero difference (roll out tests down automotive ramps I brought in to the rink) or in feel (just as smooth as any other bearing I've skated) but due to weight, having the big balls in ceramic makes a fairly big weight difference.

I'm trying to get Bones to produce a ceramic ball Swiss 6, but they don't want to. I tried contacting WIB Bearings, and they said they only distribute to Skate One in the USA (Bones Bearings are part of Skate One, or Powell Peralta)

So I'm stuck purchasing the Swiss 6 bearings (I do really like the apparent inner and outer race quality from the Swiss Bones, even if it doesn't actually make a performance difference, good machining is just satisfying) and installing the Silicon Nitride balls myself. (still need to measure the steel balls to confirm proper size)

[FlailingLlama]

Originally Posted by ursle

Your doubts are as valid as using two thick pair of cotton socks to skate because your boots are to large, or mounting skate plates opposite to the correct way, the way that provides balance and makes skating easy and pleasurable.

Ceramic balls last forever, steel rusts.



Anyway, Trom aside.

I use steel races and ceramic balls, just like I drive a Hybrid car, I love the electric but don't want to be limited to 200 miles between charges, and 1/3 of that in the cold, I'm jonesing for full electric, but it's not ready.
I'd love a full ceramic, a mini full ceramic would be the bee's knees, combine Roll-line Heliums with ceramic mini bearings, I'd buy.

Wonder what they would weigh?

Need more input about the full ceramics and Bigfoot makes a great point.

My apologies to the op for the drama, but, one of the best skate products is speed creme and another is bones ceramic bearings, a third is roll-line wheels), letting someone confuse reality for whatever reason is detrimental to skating, nobody wants to suffer a fool, and the skatelog certainly is in the sights of one.

Again, everyone needs to use their common sense, yes, bearing discussions are the gravy of skating, if you want performance, look at present day racing, skateboard downhillers all use ceramic bearings and speed creme, artistic skaters use what their coach taught them to use, and their coach was taught by their coach and the learning goes back to seperate ball bearings, 100 year old technology.

Roller speed skaters I hope use the fastest bearings, but, they were coached and need to upgrade from steel, hopefully they do.

Careful though, just because everyone uses them doesn't really mean anything. We really need a precise rolling resistance machine, that can measure the minute friction differences between different small bearings.

Hard data would be really nice for the community.

My suspicion is that bearings don't make a difference even for the fastest downhill skaters. Just too many variables to isolate a bearings actual contribution. As others have said, wheel composition and design has a far greater impact on skating dynamics.

I just like fooling around with bearings, not sure why.

Also, on the topic of Bones Speed cream... maybe they changed their formulation? I bought mine from Derby Warehouse two months ago (could be old or new stock, not sure) and it's 100% a light red oil. I haven't seen it in a grease form. Stays a liquid the whole time.

[rufusprime99]

Originally Posted by FlailingLlama

They are slightly cheaper than Bones Swiss Ceramics, but they are full ceramic, Silicone Nitride inner, and outer race, and balls.

Unless they are super low tolerance, wouldn't these bearings be the absolute best?

Thanks

Let just say, this is speculation with regard to full ceramics. One reason why I think they MIGHT not be as great as ceramic/steel is dirt. Dirt will make it's way in there eventually. And as folks have said, ceramic is hard, but can be brittle. So, in a ceramic/ceramic, you have 2 hard surfaces and the dirt in the middle. This MIGHT lead to one or the other sides to break. But with ceramic ball/metal race, the metal will be less hard and might get a small pit. This would be preferable to ball or race breaking. The harder ball will win the battle, the metal will give a little.

Now if you clean your bearings often, and it sounds like you might, being this involved in selecting your bearings, ceramic/ceramic might be for you. But, if you are a bit more lax in the cleaning dept..... ahem, well, maybe ceramic/metal would be better.

[rufusprime99]

Originally Posted by BigFoot

For what it’s worth, for the last 14 months I have been running full-ceramic bearings on my right front axel. They were expensive, but I wanted to test them for susceptibility to cracking/failure before I spent the big bucks for all 16 bearings. So far, no problems. The full-ceramic bearings are silky smooth. When I rock back and forth between axles, it is noticeable. They feel nicer than the hybrid, and much better than steel bearings. No, I don’t have “sensitive feet” and it’s not a delusion, the silky feeling is real.

Oooooh. Silky. That sounds kind of enticing. I have long been pretty "whatever" with regards to bearings. But silky sounds kinda good.

[Mort]

Originally Posted by ursle

In your opinion, which honestly Mort, doesn't include a fact, or a fact hidden by misunderstanding.
Do you have testing data that shows otherwise? Do you know the power consumption of a urethane wheel? Do you know the difference between the power consumption of the wheel and the bearings in the wheel? No? K, thanks for playing the no facts game again.


If you don't want ceramics don't buy them, but stop the stupid, others shouldn't be influenced by your prejudice, (preconceived opinion that is not based on reason or actual experience)

The information I'm going on is from actual bearing manufacturers whom I have contacted, I would call their expert advice a significant quality of experience. Additionally ut I personally know of 3 different skaters who have encountered issues from running ceramic ball bearings.

Again all you ever seem to do is slander people who disagree



The Wheels will wear out quickly The bearings will last forever, it's your money to waste.*

Maybe when you buy garbage Roll*Line Heliums, they will. Those wheels are horrible. I've had 2 sets. I would rather skate SG aerobics over them, which pale in comparison to narrow poisons, which pale in comparison to other offerings still. Heliums are junk.




Well, on your say so... I took the oil pan off my 2019 Rav4 Hybrid and lo and behold, 2 minutes later the engine seized, I don't think I believe that synthetic oil stays in place and doesn't get flung by centrifugal force or drip to earth with gravity, but if on Eart2 it works for you, don't wake up, you'll be disappointed.

You can't seriously be trying to contrast an internal combustion engine versus a radial ball bearing used in a roller skate..


Right, it only takes 20 days before a relube, which actually would be necessary per use, which points out the beauty of speed creme, it solidifies into a wax, then it warms up into an oil, it's not magic it's science, magic on the other hand won't keep the synthetic oil on the bearings, but if one uses bones speed creme, there's no magic, it's science.

As I said before, I have a bottle and it is never a paste/solid even at 50 deg or less. It's just an oil. Somehow you think that engine oil will void itself from a bearing but the speed cream which is also a liquid won't. Sounds like you're the one believing in magic snake oil, not anyone else.

Where is the data? Oh wait, there isn't any.



Your doubts are as valid as using two thick pair of cotton socks to skate because your boots are to large, or mounting skate plates opposite to the correct way, the way that provides balance and makes skating easy and pleasurable.

I use 1 pair of socks, not 2. I dont know why you keep saying this(as it's not the first time). My boots were too small by the size chart, I stretched them out, they fit like a glove. You aren't good at keeping it together are you? I do use cotton socks, they have far better grip on my feet and on the interior of the boot so the skate boot is more like a second skin. My feet are a size 12, at the upper limit of the 6- 12 size for cotton crew socks, so they fit tightly and never bunch up even if my feet get wet, like when I skated 87 miles in the rain during A2A.



Ceramic balls last forever, steel rusts.

Ceramics break, that's not in any way forever


Anyway, Mort aside.

I use steel races and ceramic balls, just like I drive a Hybrid car, I love the electric but don't want to be limited to 200 miles between charges, and 1/3 of that in the cold, I'm jonesing for full electric, but it's not ready.
I'd love a full ceramic, a mini full ceramic would be the bee's knees, combine Roll-line Heliums with ceramic mini bearings, I'd buy.*

Why not buy some then? They're available if you actually contacted a bearing supplier like Jesa or Boca, I'm sure you could get a full ceramic 688, wait let me do your research for you again.

Of look Google has it for ya.
https://www.google.com/search?ie=UTF...ll+ceramic+688



Wonder what they would weigh?*

40% less, is the usual, so let's just say half the weight when speaking of a full ceramic, youd be looking at 5grams for a pair of 688 full ceramics, but you still need the adapter rings which are aluminum, so weight savings would be negligible if none at all.

Need more input about the full ceramics and Bigfoot makes a great point.

My apologies to the op for the drama, but, one of the best skate products is speed creme and another is bones ceramic bearings, a third is roll-line wheels), letting someone confuse reality for whatever reason is detrimental to skating, nobody wants to suffer a fool, and the skatelog certainly is in the sights of one.

If it was indeed the "best" bearing lube, other companies would be coming to bones for their exceptional lubricant. Guess what? They aren't. If you have some data that show it's anything better than repackaged clipper oil, by all means, prove this product is worth anything. Considering its price is 64 TIMES more expensive than synthetic engine oil which carrys extremely refined base stocks. 32 fluid ounces for 8 bucks, or .5 fluid ounces for 8 bucks.. it's a no brainer.

Again, everyone needs to use their common sense, yes, bearing discussions are the gravy of skating, if you want performance, look at present day racing, skateboard downhillers all use ceramic bearings and speed creme, artistic skaters use what their coach taught them to use, and their coach was taught by their coach and the learning goes back to seperate ball bearings, 100 year old technology.

Roller speed skaters I hope use the fastest bearings, but, they were coached and need to upgrade from steel, hopefully they do

The amount of sheepish quality in this poster is alarming. To blindly follow a company based off of 0 scientific test results is amazing to me, all the while claiming science about their snake oil "speed cream"


I encourage anyone to contact a bearing supplier, explain your goals and ask about ceramics, and ask about using them in a skating environment where NVH is present, in some cases, a lot of it. Please , ask the real professionals if that is a good idea, and if your physical safety and well being are worth a chance of failure from ball fractures.

Hell, while you're there. Ask them about "speed cream" too.

Originally Posted by FlailingLlama

Careful though, just because everyone uses them doesn't really mean anything. We really need a precise rolling resistance machine, that can measure the minute friction differences between different small bearings.

Hard data would be really nice for the community.

what a wild idea huh? Some of the forum users around here dont care for research, they would rather speculate. They think there is only 1 way to mount a skate, 1 size fits all, and they skate outdoors on a tennis court by themselves and have 0 immersion in skating culture or variables.


My suspicion is that bearings don't make a difference even for the fastest downhill skaters. Just too many variables to isolate a bearings actual contribution. As others have said, wheel composition and design has a far greater impact on skating dynamics.

this is the facts, one wrong movement can steal valuable time, far more than any ceramic bearing will save you.

I just like fooling around with bearings, not sure why.

Also, on the topic of Bones Speed cream... maybe they changed their formulation? I bought mine from Derby Warehouse two months ago (could be old or new stock, not sure) and it's 100% a light red oil. I haven't seen it in a grease form. Stays a liquid the whole time.

It stays liquid because it's just trashy lubricant, not what they say it is, what ever they can put in those bottles buddy. Over the years I've seen it anywhere from runny vaseline to clipper oil, and now you say a reddish liquid?

They really will sell us anything huh?

I trust lubricants that are actually held to a standard.

[ursle]

Originally Posted by FlailingLlama

Careful though, just because everyone uses them doesn't really mean anything. We really need a precise rolling resistance machine, that can measure the minute friction differences between different small bearings.

Hard data would be really nice for the community.

My suspicion is that bearings don't make a difference even for the fastest downhill skaters. Just too many variables to isolate a bearings actual contribution. As others have said, wheel composition and design has a far greater impact on skating dynamics.

I just like fooling around with bearings, not sure why.

Also, on the topic of Bones Speed cream... maybe they changed their formulation? I bought mine from Derby Warehouse two months ago (could be old or new stock, not sure) and it's 100% a light red oil. I haven't seen it in a grease form. Stays a liquid the whole time.

Downhill skateboarders mill their hanger to be exact (90degrees) to the axle, use speed washers and tighten the bearing down, so no side play.

My speed creme is light yellow, I suspect your red is a switched product, my creme has always set up when cool and turns to liquid when used, there's another company releasing almost the same product, googled, gone.

In the bicycle world ceramic bearing are proven to be faster, so are roids.

In the skate world, who cares, nobody races, I use the longest lasting quietest bearings, I can only offer my opinion,

[Mort]

Originally Posted by ursle

Downhill skateboarders mill their hanger to be exact (90degrees) to the axle, yep they do, or some do. Some come from the factory this way, and some enthusiasts do it to their own equipment. All my personal skates habe the trucks/hangers cut for a perpendicular face in refrence to the axles.

use speed washers and tighten the bearing down, so no side play.
Some do, most dont, because theres too many variations in hubs to lock down with generic spacers, as they have to be virtually perfect.


My speed creme is light yellow, I suspect your red is a switched product, my creme has always set up when cool and turns to liquid when used, there's another company releasing almost the same product, googled, gone.

the stuff I have is also light yellow, and never sets up, I suspect there is very little quality control, or that they just package whatever is cheaply available. The SDS sheet doesnt give much info, like boiling points. Flash or flame points, and lists generic ingredient base. Simply put , it's nothing special.

In the bicycle world ceramic bearing are proven to be faster, so are roids.

in the downhill longboarding, the inline racing, and quad racing, superior choice in urethane has a far bigger difference than going with steel or ceramic. Especially outdoor, where the urethane thickness, hardness , hub structure etc must match the conditions one is riding on, additionally the bearings need to have specific internal clearances to perform best too, as their conditions also change from rider to rider because not all equipment is the same or perfectly made.

In the skate world, who cares, nobody races, I use the longest lasting quietest bearings, I can only offer my opinion,

Actually, people do race, but you're a hermit and skate by yourself, it's no wonder you don't know.

[FlailingLlama]

So I heard back from BC Precision, here is the material data information on the two types of ceramic balls used in ceramic skate bearings.

ZrO2 is the creamy white ceramic you may have seen, and S13N4 is the dark grey/blackish ceramic.



Main Applications - Wear and heat Resistant Part - ZrO2 - S13N4


Rockwell Hardness C scale -------------------------------------64 - 67

Vickers hardness (load 500g) - GPA ASTM C1327- 03------13.0 - 13.9

Flexural strength - Mpa ASTM C1161- 02c --------------5690 - 3850

Compressive strength - Mpa ASTM C73-------------------5690 - 3850

Young's modulus of elasticity - Gpa ASTM C1198 -01--------210 - 290

Poisson's ratio Fracture toughness - ASTM C1198 -01-----0.31 - 0.28






To compare, This is data from O1 tool steel, which is, as far as I'm learning, what the cheaper steel bearing balls are made from


Hardness, Brinell (soft annealed -delivery condition) 190

Hardness, Rockwell C (tempering temp 300-1200°F) 34.0-64.0

Elastic modulus (hardened to 62 HRC) 193 GPa

Elastic modulus (@399°C/750°F, hardened to 62 HRC ) 172 GPa

Elastic modulus (@191°C/375°F, hardened to 62 HRC) 186 GPa

Compressive yield strength (0.2%, hardened to 50 HRC) 1350 MPa

Compressive yield strength (0.2%, hardened to 55 HRC) 1800 MPa

Compressive yield strength (0.2%, hardened to 60 HRC) 2150 MPa

Compressive yield strength (0.2%, hardened to 62 HRC) 2200 MPa



To compare further, this is data from the chrome steel used in bearing balls (4140 Chrome-Molybdenum)



Hardness, Brinell 197

Hardness, Knoop (Converted from Brinell hardness) 219

Hardness, Rockwell B (Converted from Brinell hardness) 92

Hardness, Rockwell C (Converted from Brinell hardness. Value below normal HRC range, for comparison purposes only) 13.0

Hardness, Vickers (Converted from Brinell hardness) 207 MPa

Tensile Strength, Ultimate 655 MPa

Tensile Strength, Yield 415 MPa

Elongation at Break (in 50 mm) 25.7 %

Reduction of Area 56.9 %

Modulus of Elasticity (Typical for steel) 205 GPa

Bulk Modulus 140 GPa

Poissons Ratio (Calculated) 0.290

Machinability (Based on AISI 1212 as 100% machinability) 65 %

Shear Modulus 80.0 GPa




So the Poissons Ratio has a lot to do with crack propagation and fracturing, the strongest steels calculate up to 0.30, and they aren't even used in bearings. The chrome steel, which is substantially less hard than hardened tool steel (less hard usually means more crack resistance) has a 0.29.

Strength and hardness measurements from both ceramics are astronomically higher, while crack resistance is at least the same as the best steels. I'm thinking we should adjust our perception of ceramics in skate bearings being so fragile.

The improvement, if any, to the smoothness, or friction of a skate bearing with ceramic balls will be much harder to quantify.

I will be able to measure the wear characteristics on my own ceramic bearings...

I have ceramic balls in my skate bearings now, from BC Precision, I will be periodically (every time I clean and relubricate the bearings) measuring the ceramic balls for changes in size.