VEX Pro vs. AM Bearings

[jsasaki]

So today after hours of milling out our chassis rails I noticed something when I was assembling them. Unfortunately the bearings bought from VEX Pro were not to the quality I would have liked. So heres what I noticed. 1. The VEX bearings were not stamped HEX leading me to think that the bearing was broached by VEX unlike AndyMarks which is stamped FR8-ZZ now I dont know whether this is done by the manufacturer so I cant say exactly. 2. The bore/ inner ring on the AndyMark bearings look larger than the ones on the VEX Pro one. 3. when the bearing were press fitted in our Gearbox to take a hex output if would stick in one place./ when press fitted into our chassis rails and bearing blocks the fit was tight and when it did fit the would be wobble in the sprockets and wheel hubs seen in this video https://www.youtube.com/watch?v=EmbLamJat6o (I have about 10 AM Bearings and 34 VEX Pro bearings. Tried them all in different combinations) I'm not saying the VEX Pro parts are bad but just that the fit of the bearings weren't good enough for us. Just a heads up for teams and VEX.

[ttakashima]

My team and I can confirm this. I have played around with a few of jsasaki's VEX and AM bearings, the Hex VEX bearings are not centered. All other components that I've played with from vex are of excellent quality.

[Tristan Lall]

Originally Posted by jsasaki

I'm not saying the VEX Pro parts are bad but just that the fit of the bearings weren't good enough for us.

The runout of an R8 bearing is supposed to be several ten-thousandths of an inch, even for ordinary ABEC 1 or ABEC 3 bearings. Your bearings are visibly out of spec by about two orders of magnitude.

You've clearly demonstrated that those particular parts are bad in any conventional bearing application. Since the parts came that way, I'm sure IFI will be happy to speak with you about it. Hopefully their supplier will also be willing to speak to IFI about it.

(Incidentally, the shields upon which the part number is stamped are a standard part; perhaps IFI didn't want to go to the extra expense of having a custom marking put on.)

[jsasaki]

Heres a video of AndyMark bearings https://www.youtube.com/watch?v=_yZm6RUQ92U notice that these bearings dont shift around like this video at 0:27

[Jimmy Nichols]

I would definitely be contacting IFI and speaking to them. I'm sure they are going to want to know this, so that they can go back to their supplier/Manufacturer.

[Paul Copioli]

So I have a few questions from the video and I can clear up some of your assumptions.

First, the bearings are not broached by VEX afterwords. They are broached by the bearing manufacturer prior to hardening and grinding.

Second, the first shot in the first video I don't really know your setup so I can't comment on the wobble. In the second shot are you saying there is wobble in that video? In any case , please contact customer support and we can get you replacement bearings. Please be sure to give them your order number.

Third, the shield is a completely different part from inner race and we used a standard fr88 bearing shield.

Last, the absolute best way to get customer support from VEX is to call the support line or email support@vexrobotics.com

I assure you that the bearings are supposed to be ABEC1 and not have wobble like you show on your video. We use these same bearings in our single speed gearboxes and we do not see this issue.

Please contact customer support and we can resolve this issue.

[MichaelBick]

Is this on all vex bearings or just the ones that have a hex?

[Paul Copioli]

Originally Posted by MICHAELABICK

Is this on all vex bearings or just the ones that have a hex?

What question are you asking and who are you asking?

[MichaelBick]

Hi Paul, sorry for being unclear. We ordered a lot of bearings from Vex this year(FR8-ZZ Hex, FR8-ZZ, FR6-ZZ Hex, FR6-ZZ). This obviously is an unusual problem, but I was wondering if any other teams have found runout problems with their other bearings(specifically the ones we ordered). We haven't recieved our Vex order yet so I want to be prepared to check our bearings for any runout.

In our recent tests with non-hex bearings, VersaWheels, and a perfectly circular axle, the wheel, when turned, moved perfectly straight with no wobble to either side, and the bearings worked as expected.

[pfreivald]

For various reasons we've gotten .5" hex bearings from both VEXPro (80) and AndyMark (60) , and haven't noticed a problem with either.

I'm sure that the occasional bearing has a problem -- this happens with any large-quantity manufactured good -- but thus far the quality control of both products seems to be quite satisfactory.

[jsasaki]

Originally Posted by Paul Copioli

the first shot in the first video I don't really know your setup so I can't comment on the wobble. In the second shot are you saying there is wobble in that video?

Thanks for the reply Paul. Definitely will contact VEX asap. I just want to clear up with you that the VEX Pro bearings were in fact not concentric as you can see in this video at 0:27. I'm just hoping it was a small batch error but no matter what setup the bearings are in, it just wont work.

[jsasaki]

Originally Posted by MICHAELABICK

Is this on all vex bearings or just the ones that have a hex?

We only purchased half inch hex bearings from VEX

[Cory]

I would be interested in more details.

Did the VEX bearing stick before you pressed it in your bore? If not, it's possible (if not probable) that your bore could be too tight, or you pressed it in and indented the shield, or somehow damaged the race/ball interface.

Did you try an AndyMark bearing in the same bores that you displayed the runout in your first shot? Did you independently chuck the shaft and hub in a lathe/drill press/something else that spins to verify that each component spins true? Without all 3 of those actions, there's no way of isolating the problem to your bearing.

[Richard Wallace]

I'm sure Paul and his staff at VEXPro will get to the bottom of this.

Just because I am addicted to looking at details, I took a two VEXPro FR8ZZ Hex bearings (217-2734) to my lab and set up an indicator to measure run-out while the bearings were supported by a hex shaft clamped in a bench vise. They measured 0.0005" TIR on the outer race and 0.0015" TIR on the inner flange face. I have some AndyMark FR8ZZ Hex bearings (am-0279) on order and will test a couple of them the same way when they arrive.