The bearing spacer discussion

[Sunnyape]

I'll re-hash it.

I think the need for a spacer between the bearings is valid for people using wheels with axles with nuts. The spacer effectively prevents the bearing inner races from being pushed in too far if the skater over-tightens the axle nut. Pushing the races into a permanently offset position will result in premature wear when rolling. For those using flip axles, they're of no real use. There's sufficient clearance in the system that the inner races will never get into that offset position.

I've read some descriptions of spacers being responsible for transferring loads between the inner and outer bearings when cornering, which seems rational, but if you swap your wheel positions from time to time to balance their wear rates, you'll be balancing any differences in bearing wear too. Same happens when cleaning, re-lubricating and re-installing the bearings.

Skate bearings are more than capable of accommodating the side loading we subject them to will no ill affects other than marginally more wear on the sidewalls of the race channels, but probably well within the range of being proportional to the lifespan of the materials they're made from. When bearings wear out from excess side-loading induced wear, then they're probably worn out from normal use anyhow and need to be replaced.

All the other reasons I've read about spacers being able to compensate for bearing alignment, slippage in the hub, axle flex etc. all seem a little too fanciful for my liking. Even if they did perform all those duties, it's not as if you'll achieve some measurable increase in the lifespan of the bearing, the hub or the axle anyhow, because all the other normal usage and wear factors will prevail.

Then, when you factor in the variations of the spacing between the bearings due to manufacturing differences in the wheels themselves (refer to the wheel cross section pictures in the 5th page of the Show Us Your Wicked Lips thread), the idea of there being a single spacer that does its magic on all wheels gets every harder to imagine.

[fierocious1]

Originally Posted by Sunnyape

I'll re-hash it.

I think the need for a spacer between the bearings is valid for people using wheels with axles with nuts. The spacer effectively prevents the bearing inner races from being pushed in too far if the skater over-tightens the axle nut. Pushing the races into a permanently offset position will result in premature wear when rolling. For those using flip axles, they're of no real use. There's sufficient clearance in the system that the inner races will never get into that offset position.

I've read some descriptions of spacers being responsible for transferring loads between the inner and outer bearings when cornering, which seems rational, but if you swap your wheel positions from time to time to balance their wear rates, you'll be balancing any differences in bearing wear too. Same happens when cleaning, re-lubricating and re-installing the bearings.

Skate bearings are more than capable of accommodating the side loading we subject them to will no ill affects other than marginally more wear on the sidewalls of the race channels, but probably well within the range of being proportional to the lifespan of the materials they're made from. When bearings wear out from excess side-loading induced wear, then they're probably worn out from normal use anyhow and need to be replaced.

All the other reasons I've read about spacers being able to compensate for bearing alignment, slippage in the hub, axle flex etc. all seem a little too fanciful for my liking. Even if they did perform all those duties, it's not as if you'll achieve some measurable increase in the lifespan of the bearing, the hub or the axle anyhow, because all the other normal usage and wear factors will prevail.

I have used them before. Depending on hubs of the wheels the spacers would require lots of time to do perfectly. I have probably 200 pair of older 7mm skates that have the D axle ends but are precision. I went through them this last weekend preparing to cull a bunch. What I found while moving these skates is that these old skates had varying amounts of bearing bind. Some spun freely, some did not. I would say probably55 to 60% had some binding going on. I know they were probably thrown together but that is fairly common from rink skates/rentals. The plan is to take off all the wheels and as I do, check to see if the bearings free up, determine if other bearings are just junk and find out how many have spacers.
If you take the time to do spacers correctly, there will still be no gain over a flip axle setup(basically the same as a nut backed of 1/2 turn, which is where I have always ran them)...... other than a marginal increase in axle tension.

[Doc Sk8]

[B]Originally posted by forum member Machine, maybe as far back as when he went by 2 Minute Mike

Time for some tl;dr from an engineer.

I have messed with spacers quite a bit on my skates given that when I'm not on my quads I'm railing around roadcourses in a high performance race car. And guess what we put in between the bearings pressed into the suspension uprights? That's right, precision machined spacers that allow us to crank down the wheel spindle nut for all it's worth yet still maintain perfect bearing roll.

Works on the car, why not do it on the skates? Makes sense.

The issue I encountered with trying to use spacers on quad wheels is that not all quad wheels are consistent in the measurement of the webbing between the bearing seats. I've found this especially true with injection molded plastic hubs. I would find differences of a few hundredths of an inch between wheels of the same make/model in a matched set. The machined aluminum hubs were better, but not perfect. My aluminum hubbed Radar Devil Rays were a couple hundredths out on the webbing measurement between all eight wheels. Even my reproduction Fanjet hubs were not 100% identical in webbing measurement over a set of eight. They were damn close, but not close enough I could use eight identically sized bearing spacers. And it's not like I'm using a ruler and eyeballing these things, everything I took measurements with is digital and has Mitutoyo printed on it somewhere.

The only hubs I found that were consistent in webbing measurement between an entire set of eight were on my Roll Line wheels, which I hardly ever use. So, no help there. But I understand now why a lot of Roll Line wheels come with spacers, their production QA is that high.

Now a couple hundredths of an inch does not sound like a lot, but it's enough so that if your spacer is off in measurement by that amount in either direction you'll see some interesting behavior.

Spacer a couple hundredths too big? You can tighten the nut down all the way, and the wheel spins great. But the bearings are not actually seated against the webbing and you can feel a tiny bit of slop if you grab the wheel and push/pull on it. You'll feel the webbing click/clack back and forth between the outer bearing races. My concern there is that if used in that manner the friction of the hub sliding on the bearings would effectively destroy the bearing seats and webbing over time. Think of it as bending the tab on a beer can back and forth till it snaps off in your hand.

Spacer a couple hundredths too small? Well, that one is pretty obvious. You start tightening the nut down to lock the bearings in place on the spacer and it pinches the inner bearing races in so they are no longer in perfect alignment with the outer bearing races. Generally this is pretty easy to see because the wheel won't spin freely, or spins like there is a slight touch of drag. If you skated on them in this fashion you'd eventually destroy the races of your bearings or potentially seize a bearing all together.

What was my solution? I actually ended up using my digital caliper to individually measure the webbing on a set of eight wheels. I then used a mini-lathe to cut precise individual spacers matched to each wheel webbing measurement. That worked perfectly as I assumed it would. BUT, it was a big pain in the ass. And now as a side effect, when it comes time to clean those wheels/bearings I am now forced to make sure each individually machined spacer and matched bearing set stays with its corresponding wheel. Again, pain in the ass.

I even tried using standard over-the-counter skate shop quad wheel bearing spacers (it always seemed like the bearing spacers were a hair too short) and attempted to shim them with sanded down speed rings for a perfect fit. Again, not worth the headache, and now you had shims to keep matched up with your wheels/spacers/bearings... Wonderful.

My final solution was to chuck all the spacers in the trash and just run without. Tighten the axle nut till there is a hair of drag, back off 1/8th of a turn, good to go. It's a rollerskate, not a race car.

I do run speed rings on the inside of my trucks, but you don't need to run speed rings on the outside... Just flip the standard locknut over. Locknuts are all tapered on top where they crimp them over to hold the nylon in. That crimped over surface matches up perfectly with the inner race on the bearing with no contact to the dust shield.

Just remember to run the nylock nut on to the axle fully at least once before you flip it if it's a brand new nut. New nylock axle nuts do not have threads cut into the nylon fresh out of the box. Running it down on the axle fully at least once will cut in the threads making flipping the nut far easier than if you didn't preventing a potential cross-thread.

And there you go, that's my experience with bearing spacers on quad skate wheels. Not worth the hassle.

[ursle]

Originally Posted by Doc Sk8

Originally posted by forum member Machine, maybe as far back as when he went by 2 Minute Mike

Originally Posted by Two Minute Mike;

Time for some tl;dr from an engineer.

I have messed with spacers quite a bit on my skates given that when I'm not on my quads I'm railing around roadcourses in a high performance race car. And guess what we put in between the bearings pressed into the suspension uprights? That's right, precision machined spacers that allow us to crank down the wheel spindle nut for all it's worth yet still maintain perfect bearing roll.

Works on the car, why not do it on the skates? Makes sense.

The issue I encountered with trying to use spacers on quad wheels is that not all quad wheels are consistent in the measurement of the webbing between the bearing seats. I've found this especially true with injection molded plastic hubs. I would find differences of a few hundredths of an inch between wheels of the same make/model in a matched set. The machined aluminum hubs were better, but not perfect. My aluminum hubbed Radar Devil Rays were a couple hundredths out on the webbing measurement between all eight wheels. Even my reproduction Fanjet hubs were not 100% identical in webbing measurement over a set of eight. They were damn close, but not close enough I could use eight identically sized bearing spacers. And it's not like I'm using a ruler and eyeballing these things, everything I took measurements with is digital and has Mitutoyo printed on it somewhere.

The only hubs I found that were consistent in webbing measurement between an entire set of eight were on my Roll Line wheels, which I hardly ever use. So, no help there. But I understand now why a lot of Roll Line wheels come with spacers, their production QA is that high.

Now a couple hundredths of an inch does not sound like a lot, but it's enough so that if your spacer is off in measurement by that amount in either direction you'll see some interesting behavior.

Spacer a couple hundredths too big? You can tighten the nut down all the way, and the wheel spins great. But the bearings are not actually seated against the webbing and you can feel a tiny bit of slop if you grab the wheel and push/pull on it. You'll feel the webbing click/clack back and forth between the outer bearing races. My concern there is that if used in that manner the friction of the hub sliding on the bearings would effectively destroy the bearing seats and webbing over time. Think of it as bending the tab on a beer can back and forth till it snaps off in your hand.

Spacer a couple hundredths too small? Well, that one is pretty obvious. You start tightening the nut down to lock the bearings in place on the spacer and it pinches the inner bearing races in so they are no longer in perfect alignment with the outer bearing races. Generally this is pretty easy to see because the wheel won't spin freely, or spins like there is a slight touch of drag. If you skated on them in this fashion you'd eventually destroy the races of your bearings or potentially seize a bearing all together.

What was my solution? I actually ended up using my digital caliper to individually measure the webbing on a set of eight wheels. I then used a mini-lathe to cut precise individual spacers matched to each wheel webbing measurement. That worked perfectly as I assumed it would. BUT, it was a big pain in the ass. And now as a side effect, when it comes time to clean those wheels/bearings I am now forced to make sure each individually machined spacer and matched bearing set stays with its corresponding wheel. Again, pain in the ass.

I even tried using standard over-the-counter skate shop quad wheel bearing spacers (it always seemed like the bearing spacers were a hair too short) and attempted to shim them with sanded down speed rings for a perfect fit. Again, not worth the headache, and now you had shims to keep matched up with your wheels/spacers/bearings... Wonderful.

My final solution was to chuck all the spacers in the trash and just run without. Tighten the axle nut till there is a hair of drag, back off 1/8th of a turn, good to go. It's a rollerskate, not a race car.

I do run speed rings on the inside of my trucks, but you don't need to run speed rings on the outside... Just flip the standard locknut over. Locknuts are all tapered on top where they crimp them over to hold the nylon in. That crimped over surface matches up perfectly with the inner race on the bearing with no contact to the dust shield.

Just remember to run the nylock nut on to the axle fully at least once before you flip it if it's a brand new nut. New nylock axle nuts do not have threads cut into the nylon fresh out of the box. Running it down on the axle fully at least once will cut in the threads making flipping the nut far easier than if you didn't preventing a potential cross-thread.

And there you go, that's my experience with bearing spacers on quad skate wheels. Not worth the hassle.

Thanks doc, a been there done that by someone that knows.
Still love a chart of the specs for all the wheels available, I bet bones wheels are rather well machined, metal and non metal, Scotty's hubs I'm sure are also uniform, and all the older metal speed wheels.
Speed washers are available in 1/2mm and 1mm widths for 7 or 8 mm axles.
Love the flip the nylon nut over to align with the bearing precisely, but pre-thread the nylon.

[amohrfeld]

Doc said it all. And then some.

[fierocious1]

Originally Posted by amohrfeld

Doc said it all. And then some.

Totally logical answer from Doc. Too much time for virtually zero gain. Probably not measurable gain..

[amohrfeld]

Originally Posted by fierocious1

Totally logical answer from Doc. Too much time for virtually zero gain. Probably not measurable gain..

There are so many other factors that have a greater impact. Once these factors are perfected, then focus on bearings. And most of us may never make it that far.

I installed Roll Line Wheels yesterday. They come with spacers. But the spacers are about .010" too short to do anything. What's the point if the spacers just flop around on the axle?

[fierocious1]

Originally Posted by amohrfeld

There are so many other factors that have a greater impact. Once these factors are perfected, then focus on bearings. And most of us may never make it that far.

I installed Roll Line Wheels yesterday. They come with spacers. But the spacers are about .010" too short to do anything. What's the point if the spacers just flop around on the axle?

Yep... the bearing spacer fix is at the very bottom of any skate fix list I have.
Cushion testing though is near the top

[Mort]

There are factors where bearing spacers make a difference.

I totally agree that getting bearing spacers properly set up is not an easy task. I'm all for tinkering and making stuff if I can, but even measuring the hubs and getting spacers cut to fit sometimes doesn't work out. Small margins of error in measuring can nullify the spacers usefulness.

Let's presume they are perfectly cut to each hub, well that allows a skater to lock the inner race assembly in place. This does NOT lock the outer races in place, So true load sharing is only accomplished by locking both the inner and outer races in place. Sure most wheels have a descent grip on the wheels hub, but not enough to keep still under the strength of a hard stride.

The o e thing that spacers do allow even without the outer races fixed in place is vibration dampening. Which makes a good difference in grip, and the way slides can be invoked or maintained.

I made my own spacers for my Royal assassin wheels out of 1 608 inner race and 1 688 inner race. To make them fit right, I had to hand lap the 608 inner races down from .275 to .268 or so. Some needed .271. Combined with the 688 inner races I had spacers about 11.9mm wide.

This makes a very noticeable difference for my skate, and not so noticeable for some others, depending on how tight the fitment is between their axles and the bearings inner races, it changes things.... My example? My axles have a small dip in them at the threads, where the outer bearing sits. This allows some slop on the outside bearing which gives the assembly a bit more play. Sliding techniques are easily done, and grip is reduced. When I tighten them all the way down and the spacers prevent that slop from happening, i gain a stabilizing effect on the wheel and it also gains vibration dampening. If you've ever heard the difference between inlines and quads hockey stops(typically) you'll know what I mean. Their sounds are distinctly different. My skates have a trademark "quad hockey stop" noise with the nuts backed off a smidge, but a screech with them tightened all the way down.

Spacers also brace the axle, but again you would want the tightest fit on the axle possible. I got a nice set of 8mm spacers made for a set of scotts wide phantoms. They do a great job and fit VERY snugly on the axles. Unfortunately each wheel has its own spacer. Lol like what was previously mentioned. Though when my buddy wants a bit more grip, he just snugs the axle nuts.

I loctite'd a set of bearings in once, but the way I did it was flawed due to the bearing press I used, So only 2 wheels worked right. However I did like the results, very pleasing to roll, just didn't end up with 0 drag on all the wheels. Thanks to my Snyder bearing press having too much bevel to make square contact with both the inner and outer races..... grr....

I also used loctite to secure bearings in a set of poisons(plastic hubs this time) ,same thing with the bearing press, just didn't realize it back then. That test also checked to see how it would affect the hub deformation Atom wheels usually are known for. With the outer ring of the bearing chemically bonded to the hub it definitely made a difference, but cornering at speed still was not good because the wheels urethane simply had too much flex, and would deflect under load, which made it turn less, even though it might have had more grip than say a harder wheel. Alot of the front axle stuff I do changed dramatically when I modded those wheels, and a simple spacer would not have had the same effect. Since it held the alignment of the outer races to the hub via the loctite, the bearings experienced less torque on them because the hub was not able to deflect like it could before. Anyone who has ran a set of plastic hubs knows they are hard to get bearings in when new, but hours of hard use later, the bearings fall out. Like a sloppy metal hub lol.

Even outdoor pure urethane wheels that people "think" you need spacers for so they hold still in the hub d ont need them. In fact, they are the worst wheels to even try to use spacers in. The outer race is going to go where the wheel deforms to, reguardless, all using a spacer does is potentially cause more drag in that setup. Best just to let them move where they want with the axle nuts backed off 1/8th of a turn.

I agree that the pursuit of a perfect wheel assembly is second to almost everythibg else though.

Everything matters in your skate assembly. However , how much does it matter? Poor flip guys out there though, they'll not ever get to make full use of a spacer setup :/ even if they got it perfect.

@ URLSE

I have had 3 sets of Rollerbones Turbos, Most run .280 inch, but some go up to .285 or down to .278 and while all the bearing seat widths have been close. They are not close enough to produce 1 size spacer. And Bones does not make spacers that are precise enough to be consistent for even a set of perfectly made wheels either.

[Dekindy]

Suregrip recommends speed washers and spacers for Zombie wheels and from reading it appears that Zombie hubs are very well machined so I ordered some spacers and enough washers to install inside and outside. Powerdyne Reactor Neo is my plate.

Can now tighten down the wheel nut all the way instead of going through the tedious process of adjusting them until play and binding sweet spot is achieved. Wheels roll forever without load now which I know is no indication how they perform under load but it is satisfying however irrational. I am not an expert at evaluating wheels nor do I even come close to challenging the performace level of my equipment; but they do feel smoother and faster while skating. Worth it to me for the convenience of easier wheel installation.

Based on my research this is a rare result. Most wheels hubs are not machined precise enough and/or otherwise cannot benefit from washers and spacers.

[Mort]

EVERY zombie hub I have measured read .2995 inch

[fierocious1]

I tore down about 50 pair of old skates. Some were 7mm and some 8mm. Some observations.
1. Most 8mm bearings were junk. They are cheap and just did not hold up to skate duty with no maintenance. However some 8mms were fine. These skates were old enough that spacers were still in the wheels for the most part. These wheels were typical Labeda rentals, and others that were made of urethane. The wheels had no hubs so the bearings could seat if they were a little snug.
2. Plastic hubbed wheel's hub can give a little over time, where it may take longer for metal hubs to wear if things are tight.
3.On the 7mm, all had spacers. The wheels varied in tightness, I would estimate that about 70% were too tight.
4. There were lots of bad bearings in the bunch as well. Been setting too long. Most of the time I would find that usually both bearings in a wheel would not be bad. But bad bearings, worn bearings dry bearings all were present.
5. I could loosen up the nuts of the tight ones and about 50% of the time the wheels would roll better.
6. A lot of these skates did not have nylocks. 100% tensioned axles to lock the nuts.
7. A lot of 7mm bearings were actually fairly smooth rolling and could be used again. They were dirty but I could make out that they were made in USA.
8. Also, more 7mm bearings were in good shape compared to the 8mm bearings. By a lot! Out of the app 50 pair, I probably got 2 or 3 sets of 8mm. Way more than that in 7mm.

I salvaged a lot of old rink wheels that would be good for the slider guys out there. Also got a lot of the old hub cap bearing shields with their spacers too. Some of the wheels are in pretty good shape. I have no idea if the slider dance guys hunt for the old stuff or not for retro style skates but I have some stuff if it is needed. Even some old roller bearing Metalflex wheels too.

After all this, bearing spacers are good on 100% tensioned axles on wheels with no hubs, the spacer will stabilize the wheel somewhat. Wheels with hubs don't really need them. The biggest difference is that a lot of these skates also had 100% tensioned axles because of using older plain nuts, not nylocks. Nylocks solved a lot of issues when they were introduced to skates. If you are running metal hubs, really no need for spacers.

Edit: Maybe spacers would have prevented the hub caps from falling out of the Atom Strokers several years ago... possibly preventing hub flex. All hubs are not created equal. Some plastic hubs flex.

[Sunnyape]

Originally Posted by Dekindy

Suregrip recommends speed washers and spacers for Zombie wheels and from reading it appears that Zombie hubs are very well machined so I ordered some spacers and enough washers to install inside and outside.

Did you order the spacers from Sure-Grip? If not, did you try and find ones of a specific length to match the Zombies, or just took what you got and it happened to match?

[Dekindy]

Originally Posted by Sunnyape

Did you order the spacers from Sure-Grip? If not, did you try and find ones of a specific length to match the Zombies, or just took what you got and it happened to match?

Ordered from 2n1 skate shop.

[amohrfeld]

@Lloyd

Any wood wheels? or Clay wheels?

[dvw]

If you're using wheels with no bearing hub, like the old Metaflex wheels, any vanathane like the Fo Macs or that type of wheel then yes, spacers are a definite performance boost. Even the hardest vanathane or composite wheel will give enough to misalign the bearings and cause binding. Spacers are just the ticket.

But that's it.

I've played with them at length and the point of diminished returns isn't even a fingertip away.

If you have a bunch of free time and the inclination to do what Mort did, you can measure each wheel and hand form a spacer that fits it perfectly and you'll likely perceive some vastly immeasurable benefit. But woe is unto you if you get your spacers and wheels mixed up.

And Mort's example is a good one. Production tolerances are plenty tight enough for skate parts, but a few thou variation will make or break a spacer setup. I mean, if you're going to split hairs, split them all.

So sounds like Zombie hubs hold tolerance pretty well. Wonder how precise the spacers are?

Yeah, been there, done that.

[fierocious1]

Originally Posted by amohrfeld

@Lloyd

Any wood wheels? or Clay wheels?

So far no clay wheels. Possibly some woods in there. A few old 7mm roller bearing wheels. I still have 2 crates to go. Am pulling all unusual wheel sets aside. Several sets of roller bearing Fo-Macs. Wife had a set of them on her old skates originally too in roller bearing.

[1M_E]

this eliminates the spacer issue!
http://www.skatelogforum.com/forums/...ad.php?t=54656

[AZSHOT]

Originally Posted by Sunnyape

I'll re-hash it.
...The spacer effectively prevents the bearing inner races from being pushed in too far if the skater over-tightens the axle nut. ...

Then don't over tighten the nut. Solved. I pitch the spacers of any skates I pull wheels from now, usually when scavenging good bearings from so-so wheels.

[Abyss]

Do ppl actually toghten the axel nut all the way to the bearing now days? This is something i have never seen nor heard of from back when i skated alot and at many dif rinks. Everyone who was a “good skater” (those that could spin an do tricks etc) always left play in the wheel. Since no one used toe stops for anything functional, we’d essentially slide or drag our wheels sideways to stop and/or change direction on a dime even at speed. Worked like a charm but doesnt work if the wheels have no play. We all knew it was supposedly hard on the bearings but i font know of a single person ever that didnt get years of bearing life even from cheapys (myself included) so long as they maintained them regularly.
I just found the spacer discussion interesting as i was unaware anyone actually tightened their wheels enough for it to katter as i was brought up leaving them intensionally loose (and still do to this day with no issue)