Custom ACL Bearings, thoughts?

[charliev68]

ACL RBs looks like it has an abradable coating. If it does…wouldn’t it be a waste of time to surface treat (WPC) a sacrificial coating?

[Green-Eggs]

Here's what troubles me. A few months ago, our customer bought a set of these "custom measured" bearings. By all appearances, they were still in their original ACL shrink wrap. This meant something to me because I've never seen a consumer owned machine with this same exact (thick) plastic. So I asked the customer to check for measuring marks. Any measuring device, whether a roller bearing or ball-anvil micrometer, will leave a mark of some type. No marks were present on any of the shells. As deansbimmer said, he's the only person that I've heard of that actually measures ACL shells (and he can prove it).

I'm not saying that the latest sets are the same, but as of a few months ago, this is what we found.

[Green-Eggs]

Originally Posted by charliev68

ACL RBs looks like it has an abradable coating. If it does…wouldn’t it be a waste of time to surface treat (WPC) a sacrificial coating?

ACL shells are not coated, and do not contain a low-friction surface.

[S85 builder]

Originally Posted by Green-Eggs

Here's what troubles me. A few months ago, our customer bought a set of these "custom measured" bearings. By all appearances, they were still in their original ACL shrink wrap. This meant something to me because I've never seen a consumer owned machine with this same exact (thick) plastic. So I asked the customer to check for measuring marks. Any measuring device, whether a roller bearing or ball-anvil micrometer, will leave a mark of some type. No marks were present on any of the shells. As deansbimmer said, he's the only person that I've heard of that actually measures ACL shells (and he can prove it).

I'm not saying that the latest sets are the same, but as of a few months ago, this is what we found.

I was suspecting that (no actual measuring or even opening of the factory shrink wrap) as well when this first started happening. That said, at an OEM engine plant that I had prior experience in, production bearings aren't binned, and we'd use air gauges so there aren't marks, and give a definitive go, no-go indicator for the assembler, and interfaces with the PLCs and data logging operations.

When we layyed out engines for inspection, everything like this is measured on a CMM in a vey controlled inspection room. No marks left behind.

To be clear, no reseller is doing this, only large companies have metrology equipment like this, it's way too expensive. This is how Cleveite would layout their bearings in their audit/inspection, because as you know, the curve of the shell matters alot.

[Green-Eggs]

3

Originally Posted by S85 builder

I was suspecting that (no actual measuring or even opening of the factory shrink wrap) as well when this first started happening. That said, at an OEM engine plant that I had prior experience in, production bearings aren't binned, and we'd use air gauges so there aren't marks, and give a definitive go, no-go indicator for the assembler, and interfaces with the PLCs and data logging operations.

When we layyed out engines for inspection, everything like this is measured on a CMM in a vey controlled inspection room. No marks left behind.

To be clear, no reseller is doing this, only large companies have metrology equipment like this, it's way too expensive. This is how Cleveite would layout their bearings in their audit/inspection, because as you know, the curve of the shell matters alot.

For non-OEMs, Mahle Clevite only measures about 1 in every 300, and it's strictly a go-no/go test. I have no idea what they do for OEMs, but it's clear that the red/blue shells come from a single manufacturing process because the span of thicknesses exactly matches the span that BE gets on STD (or 025mm) shells from Mahle/Clevite. Mahle Motorsports visually inspects every shell, and measures about 1 in every 5 (go/no-go). Bert's been to Mahle Motorsport in Scotland and saw how they do it; it's not an air gauge, it's a simple ball-anvil dial indicator built into a shell holder. For F1 bearings, Mahle Motorsport measures 5 points around the shell to check for eccentricity. For normal customers, they only measure at 90-degrees, and about 1 in 5 shells.

BE owns an air gauge for measuring shells. You can read about it somewhere on Facebook. To get absolute shell thickness, you need to use differential measuring. Dual air gauges didn't work. So the back side is LVDT and the under side in air. Cost was over $10k. You are right, it doesn't leave a mark.

As it relates to this thread, nobody could convince me that this small company has done anything similar or has the technical ability to have one designed for them (as BE did from Mahr). Then there would be all of the software that would need to be custom-written to operate it. So yeah, no way in heck are they using an air gauge.

But as it turns out the differential air/lvdt rig wasn't really that repeatable. Mahr is now redesigning it for dual LVDT. Once again, that will end up leaving a small mark on the surface of the shell.

[S85 builder]

What follows is all some what pointless metrology nerdiness, we both agree that NO reseller/retailer is doing this. I personally don't believe that any one needs to go to these lengths because it's overkill and at this level of resolution the con rod bore and crank rod throw dimensions actually matter more.

It's up to the OEM and vendor to agree on the statistical process control methods and CpK (statistical process capability). 1 in 300 is perfectly acceptable if the CpK shows that it's within the bounds. All of that is part of the PPAP qualification process when OEMs select suppliers.

I am very well versed in this since that was my job in an earlier life for where clearances and tolerances are actually very tight and affects operation (auto trans valve body machining, assembly, and operation) Federal (now merged with Mahr) is the only game in town for air gauging, and 10k is a pretty low cost setup in '23 USD vs 20-30 yrs ago, a setup for one of these systems would easily run 2.5x that. I was the guy that would spec this process, get RFPs, get it installed and integrated to the line.

CMMs are the "legacy" metrology method of laying out such a part, because the thickness and curvature matter alot. Entry level CMMs are 40k.The probes do not leave a mark. Most machine shops have relationships with outfits that can do the metrology beyond hand instruments.

Modern metrology is even better, faster, and equally precise & accurate. Scattered light and laser profile scanning can generate the complete surface profile in seconds. They don't leave a mark. I know for a fact that OEMs are using scattered light scanning for measurement while doing final assembly of key engine components, like the cylinder head to assure certain features are machines correctly, and assembled components are in place. It does this all in less than 5 seconds and it's integrated in to the assembly line, no clean room. I could only have dreamed to have that tech 25 yrs ago. I could have saved millions in warranty expenses.

Originally Posted by Green-Eggs

as BE did from Mahr

I was thinking you meant to say Mahle here, not Mahr. There is a cottage industry of precision gauge builders that make thaw actual fixtures using stuff from Mahr/Mitutoyo/Tesa etc. It doesn't change what you said. If I were Bert, I'd measure these using a different methods, air gauing is old school and requires alot of specific fixturing, modern methods are more precise and may be the same cost after all is said and done and are somewhat universal.

[Green-Eggs]

Originally Posted by S85 builder

I was thinking you meant to say Mahle here, not Mahr.

It is Mahr. Bert tried light, but that didn't work. So dual LVDT is what he will end up with.

His measuring station is all custom written software (that's his contribution), and logs to a database. The measuring touchscreen gives transparent green (go), or red (no-go), along with measurements for binning.

[S85 builder]

I think blue laser is the way for something like this, since it's single point. Scattered light might be too hard in one shot, you'd need a positioner turn table to get 3 shots, along with really tight camera calibration. The issue for a solution like this is the metrology software to do 3d surface deviation plots is 20k by itself.

I might try this out myself with some old bearings when things slow down later this quarter.

[Abdul]

Don’t want to start a long conversation here. But I’m forced to correct the narrative. I’m a very small business but I do MEASURE the bearings before shipping them out to customers. Albeit, I just started this service one month again and have not advertised it nor have I updated the website. In the past, I did not think it was useful to measure the shells to ensure they are within spec and I would just rely on the manufacturer date like the rest of the vendors do.

I was motivated by conventions like this to just go above and beyond. No shortcuts here – we've avoided handheld tools and in-house measurements. Each batch is certified by a third-party metrology lab to meet the exact specs we've set, ensuring unparalleled accuracy. Any shells that don’t meet the criteria are not used to make sets. I will start another thread at a later date discussing the details of this process.

The machines used to measure are 150k machines. Nothing comes close to the precision of these machines. Take a look at following videos to see the process. I just uploaded them on YT so I can share them here.

https://youtu.be/I7XekCWfdAU?feature=shared

https://youtu.be/uwvbqXxziw4?feature=shared

[Abdul]

https://www.facebook.com/share/p/o1n...ibextid=WC7FNe

[M3SQRD]

Interesting that someone felt they needed to “correct the narrative” when no company names were mentioned in this thread. “Batch is certified” and individually measuring each shell is not the same thing. “Hand tools” work fine if you know what you’re doing. I’m curious to know what the cost of a set of ACL custom matched sets is compared to regular ACL sets.

[Abdul]

Originally Posted by M3SQRD

Interesting that someone felt they needed to “correct the narrative” when no company names were mentioned in this thread. “Batch is certified” and individually measuring each shell is not the same thing. “Hand tools” work fine if you know what you’re doing. I’m curious to know what the cost of a set of ACL custom matched sets is compared to regular ACL sets.

Each shell is measured. But I’m not giving them one shell at a time, I’m giving them batches of 100’s. If you watched the videos I posted, you could see that each shell has 3-4 points to measure. The shells are measured by themselves and then they are also measured as a set in the rods. The metrology stuff is above my pay grade. I just told them what I want to accomplish and they suggested a process that I should use and I went with it.

The cost is not going to be much more than the mixed set I already sell. Maybe $40.00-$80.00 more. I’m doing this hundred percent as a passion and I can careless about the profit margins. People can buy whatever bearings they want, just not OEM. Heck, I have BE bearings in my m3. I have 💯 percent respect for what they are doing. But the more options we have, the better it is for the end user. I firmly believe that if you buy ACL bearings that are not measured, nothing will happen to your car. This is just an added benefit for people who want the extra assurance. I’ll continue selling extra clearance bearings on my website along with these ones I’m about to launch in a few days.

It was mentioned that “NO” company measures bearings. It was a general statement. That was clearly wrong. So I corrected the narrative.

[M3SQRD]

Originally Posted by Abdul

Each shell is measured. But I’m not giving them one shell at a time, I’m giving them batches of 100’s. If you watched the videos I posted, you could see that each shell has 3-4 points to measure. The shells are measured by themselves and then they are also measured as a set in the rods. The metrology stuff is above my pay grade. I just told them what I want to accomplish and they suggested a process that I should use and I went with it.

The cost is not going to be much more than the mixed set I already sell. Maybe $40.00-$80.00 more. I’m doing this hundred percent as a passion and I can careless about the profit margins. People can buy whatever bearings they want, just not OEM. Heck, I have BE bearings in my m3. I have �� percent respect for what they are doing. But the more options we have, the better it is for the end user. I firmly believe that if you buy ACL bearings that are not measured, nothing will happen to your car. This is just an added benefit for people who want the extra assurance. I’ll continue selling extra clearance bearings on my website along with these ones I’m about to launch in a few days.

It was mentioned that “NO” company measures bearings. It was a general statement. That was clearly wrong. So I corrected the narrative.

I tend to not watch posted videos for multiple reasons.

Measured as a set IN rods? What advantage does this provide when rods have their own tolerances; i.e., how does this help when the end user will have rods of different size/profile?

The word “no” must’ve been used loosely because it’s been known for quite awhile now, and mentioned in this thread, that deansbimmer has been selling mixed sets of measured ACL rod bearings. ACL bearings packaged as being measured sets when they weren’t actually measured have been sold by vendors. The “narrative” seems right in this thread.

[Abdul]

I’m not a metrology lab expert but I believe it’s just an added method to check for circularity. Not necessarily , bearing thickens. That’s done on a separate machine. I can send you all the files with all sorts of numbers they included if you like.

I also gave them a set of BE bearings, VAC bearings, King bearings and both ACL bearings. H and HX. Without a doubt, BE bearings were the most consistent with the clearance specs. ACL bearings were shockingly extremely consistent as well according to them.

Yes, the word “NO” was used loosely and I was just replying to that. That’s all. It’s not deeper than that.

[S85 builder]

Originally Posted by Abdul

Don’t want to start a long conversation here. But I’m forced to correct the narrative. I’m a very small business but I do MEASURE the bearings before shipping them out to customers. Albeit, I just started this service one month again and have not advertised it nor have I updated the website. In the past, I did not think it was useful to measure the shells to ensure they are within spec and I would just rely on the manufacturer date like the rest of the vendors do.

I was motivated by conventions like this to just go above and beyond. No shortcuts here – we've avoided handheld tools and in-house measurements. Each batch is certified by a third-party metrology lab to meet the exact specs we've set, ensuring unparalleled accuracy. Any shells that don’t meet the criteria are not used to make sets. I will start another thread at a later date discussing the details of this process.

The machines used to measure are 150k machines. Nothing comes close to the precision of these machines. Take a look at following videos to see the process. I just uploaded them on YT so I can share them here.

https://youtu.be/I7XekCWfdAU?feature=shared

https://youtu.be/uwvbqXxziw4?feature=shared

Based on this, I retract my statement. Abdul has absolutely layyed out these bearings using established CMM practices as evidenced in the video. Respect!

This is more accurate and precise that what any one else does based on their own descriptions. Furthermore, Abdul can get a true 360 deg profile of the bearing ID from the met report. This can only be plotted manually if measuring by hand or an air gauge.

That Zeiss is way more than 150k but that's what you'd expect at a met lab in Michigan. This is what real blue printing is all about.

The thing to consider here is that as these bearing are placed in the con rod
and when the bolts are tightened, the net shape of these change, this is by design. If there is dirt, burrs, or out of tol con rod big end bores, then the bearings will essentially take that shape.

Where are all the "oh he's also in Michigan" arm-chair losers?

[S85 builder]

Originally Posted by M3SQRD

I tend to not watch posted videos for multiple reasons.

Measured as a set IN rods? What advantage does this provide when rods have their own tolerances; i.e., how does this help when the end user will have rods of different size/profile?

.

The 2nd video shows a typical CMM program to measure cylindricality. yes all rods are slightly different, but they should fall into a pretty tight distribution, it's a precision bored feature, but yes once those rod bolts are torqued, those bearings effectively become sized to that rod. The design of the rotating assembly and spec of the bearings have to account for con rod bore variation. Only a real engine machinist has the equipment and tooling to resize con-rod big end bores. I've seen no proof that the rod ends have a sizing issue that contributes to the S65/85 rod bearing issue. I believe Van Dyne investigated that a decade ago.

I didn't do a slow mo to count but they seemed to measure 6-10 points around the cylindrical ID surface, if he measured at those same points but near the top and bottom he'd also have taper. However, I think this is too small to matter on the bearing, but on the crank rod it's absolutely critical. BMW AFAIK provides no published tol specs.

[S85 builder]

Originally Posted by Abdul

It was mentioned that “NO” company measures bearings. It was a general statement. That was clearly wrong. So I corrected the narrative.

I did indeed say in a prior post in this thread:
"What follows is all some what pointless metrology nerdiness, we both agree that NO reseller/retailer is doing this. I personally don't believe that any one needs to go to these lengths because it's overkill and at this level of resolution the con rod bore and crank rod throw dimensions actually matter more."

I retract part "NO reseller/retailer is doing this" Abdul demonstrated that he is with the bearing option he's selling. It was appropriate for him to correct the narrative.

[M3SQRD]

Originally Posted by S85 builder

The 2nd video shows a typical CMM program to measure cylindricality. yes all rods are slightly different, but they should fall into a pretty tight distribution, it's a precision bored feature, but yes once those rod bolts are torqued, those bearings effectively become sized to that rod. The design of the rotating assembly and spec of the bearings have to account for con rod bore variation. Only a real engine machinist has the equipment and tooling to resize con-rod big end bores. I've seen no proof that the rod ends have a sizing issue that contributes to the S65/85 rod bearing issue. I believe Van Dyne investigated that a decade ago.

I didn't do a slow mo to count but they seemed to measure 6-10 points around the cylindrical ID surface, if he measured at those same points but near the top and bottom he'd also have taper. However, I think this is too small to matter on the bearing, but on the crank rod it's absolutely critical. BMW AFAIK provides no published tol specs.

Yes, tolerances are tight in any rotating assembly; however, it’s small tolerances that do or don’t get you in trouble. I don’t need to be an engine builder to realize measuring rod bearings that are going into a different engine with different rods should not be pre-measured in a random set of rods. An unnecessary step that adds no real value. So , as an engine builder, you’re comfortable with installing a set of rod bearings, uninstalling them and then randomly reinstalling them in an engine?

Still disagree with the need for the “narrative” change. It’s widely known deansbimmer has been measuring and selling custom sets of ACL rod bearings for quite sometime now. IIRC, someone in this thread was still selling BE bearing and BE rod bolts after their relationship with BE had ended. I wonder who that was?

[S85 builder]

I don't agree that stuff like which vendors actually measure (and which merely repack bearings) is commonly held knowledge. Certainly not outside this small forum. How they measure and the accuracy matter too.

Hypothetically, if factory rod end ID's have a tolerance +/- 0.00020" and they can maintain this tol, there might be no issue with using a random set of rods.

They could very well be within the total stackup tol of the assembly (bearing inserted to the rod end), which might be +/-.00090". Ridiculously tight tols are why F1 engines cost what they do.

In real volume production, you have to have an wide enough tol otherwise you end up with assemblies with stack up error that can't meet the tol, and you get high scrap rates or excessive failure rates. You also can't really have interchangeable parts, so effectively there's poor serviceability.

[Abdul]

Originally Posted by S85 builder

Based on this, I retract my statement. Abdul has absolutely layyed out these bearings using established CMM practices as evidenced in the video. Respect!

This is more accurate and precise that what any one else does based on their own descriptions. Furthermore, Abdul can get a true 360 deg profile of the bearing ID from the met report. This can only be plotted manually if measuring by hand or an air gauge.

That Zeiss is way more than 150k but that's what you'd expect at a met lab in Michigan. This is what real blue printing is all about.

The thing to consider here is that as these bearing are placed in the con rod
and when the bolts are tightened, the net shape of these change, this is by design. If there is dirt, burrs, or out of tol con rod big end bores, then the bearings will essentially take that shape.

Where are all the "oh he's also in Michigan" arm-chair losers?

Thanks a lot! Please stay active on the forums. Your insight and feedback is very helpful and appreciated.

[Carzuhuz]

I went with BE bearing customization for my RB service, and yes, the clearance is around 0.025". It's a bit on the higher side, but many swear by them for reliability. Haven't heard much about ACL's oversized set, so can't comment on that.

[Abdul]

Hundreds of shells being measured at the metrology lab! We’re taking precision measurements to another level.

https://youtu.be/4sUWidazz98?feature=shared