ABEC 7 bearings in skateboards?

Probably more of a lie than clever marketing. I use ABEC-7 bearings in my Shimano Curado fishing reels and they really are slick. I get them here:

they aren't that cheap, but Mike sells them for less than anywhere else I've found. As far as I can tell, ABEC-7 bearing are supposed to have ceramic balls/rollers and I have my doubts about how much shock they could take on a skate board type use.

I've

Not necessarily, ABEC 7 refers to precision, I think. Mine have steel balls. I have no doubt they really are abec 7.

I also saw a lot of "ABEC 9" skateboard bearings on eBay, what a B.S.

i

You can't trust the skate and skateboard manufacturers. From the beginning they were designing in those bearings way beyond their specific load limits, putting many 100s of lbs onto 608 bearings. They're children (when it comes to engineering) marketing to children. Not that they haven't been very successful commercially in many cases.

Take that premise and run it through eBay, and you've got utter nonsense.

I was at a Favnir or SKF class a few years ago. They said they didn't make an ABEC 1 and a 3 was likely to be a 5 since their goal is to make good bearings.

Wes

I had a long discussion with a particularly stubborn friend of mine about this very topic.

ABEC 7 is the grade used for machine spindle bearings, and is obscenely expensive (when the tolerances are held to +/- 0.0001", you'd kinda expect it to be). Nearly all ABEC 7 bearings I've ever encountered were tapered roller bearings. The skateboard manufacturers just use it as a cool name, most skate bearings are ABEC 3 at best. Most non-engineers aren't aware of the real system.

Fafnir actually makes both real bearings (I think they're a subsidiary of Timken now) as well as skate bearings. I have some Fafnir machinery bearings, they're good stuff. Usually the shields on the skate bearings are colored a bright color, the ones I have are either green or red. The equipment bearings have black shields or are unshielded.

The one I have, is a ball bearing. (a pair actually).

Makes sense.

I doubt that Fafnir would mislabel even skate bearings. I think that I will buy those fake "ABEC 7" skate bearings, and will try to measure their balls' concentricity.

i

Dang! Aren't we allowed to have pretty bearing shields in our lathes and mills then?

Mark Rand RTFM

ceramic bearings are used in a locally made, internationally marketed, model jet turbine. I asked the guy how much shock load a ceramic bearing could take. "Hmmm let me show you" He had a beairng that they had cut apart using a dremel cutoff blade and took a ball out of the bearing. on the back peening pad on his 6" bench vise he placed the ball. then he gave it one almighty whack with the largest size ball pein engineers hammer. I mean he really laid into it! on the bench vise could be seen a hemispherical dimple that looked to be half the size of the ball. in the face of the hammer was a smaller hemispherical divot. the ball itself was lost down the back of the workshop because we heard it smack the rear door.

some of those little balls can be damn near indestructable.

Stealth Pilot

Ouch! Why would he do that to his vise or hammer? Or potentially either of you? That certainly demonstrated his point, but you have to wonder about his thought processes. I bet he's done the same trick before.

Pete Keillor

Hey, these look good for a project I have in mind. Do they have lower low-speed starting and rolling resistance than lesser bearings? The project is a little cup-type aenomometer. I got the hemispherical cups last week.

I don't know about the starting and resistance you ask about, I don't have that technical knowledge, but they sure make a bait casting reel sing. It is said that is they are too fast dry, uncontrollable, use light oil to slow them down some. I use an oil called Yellow Rocket Fuel on mine, it's very light and seems about right for me. Boca bearing might be able to answer your questions.

RIght. My understanding is that they try to make the best bearings that they can. Then test them and sort them into the various grades. If they managed to make mostly bearings that meet ABEC-5, they sell all they can as ABEC-5, and the rest are sold as ABEC-3.

Dan

There is a company selling skateboard bearings that is named "ABEC-7" and it has nothing to do with their quality. You are correct that a true ABEC -7 bearing meets extremely tight tolerances.

Not necessarily. Most ABEC-7 bearings are all steel - ceramic is a totally different animal for different purposes - primarily heat and electrical isolation.

You may get just the opposite effect. Because the tolerances are held so closely you may have less internal clearance (unless you specify more). Best bet is to consider the lubricant and use a minimal amount of very lightweight oil.

Most of the ABEC - 7's will be Angular Contact Ball Bearings or Single Row Deep Groove Ball Bearings.

Shields are usually left in their natural metallic color whereas seals are colored with the colors denoting the material.

Maybe I should open a company called "18k Gold" and start making crap jewelry...

i

None of the major manufacturers will mislabel any bearings and in fact strive to make everything as close to the middle of the tolerance range as possible which is why bearings sold as ABEC-1 will usually meet ABEC-3 standards (from the majors). DuPont did a comparative study between the largest bearing manufacturers in the world and checked manufacturing processes, quality control procedures, metallurgy etc. and ranked them accordingly. NTN was determined to make the highest quality bearing followed by NSK, FAG and SKF in that order. Fafnir wasn't large enough at the time to be considered but they do make a fine bearing (as do all of the above). All make high quality bearings that meet or exceed the standards but there was a slight variation in the adherence to the center of the tolerance range, concentricity etc. This is not necessarily true of some of the "off brands".

I spent approximately $7 and will soon receive those "abec 7" skate bearings. I will then try to measure concentricity of their balls when I receive them in a few days.

i