Mechanical Engineering question...
 

Hi;

I know that many of you engineer types lurk here in OT along with many others who may not be engineers but are very sharp when it comes to 911 suspension knowledge and know-how...

I pressed the bearing out of an Elephant Racing Quick Change Camber Plate in order to determine the exact manufacturer and part number of the bearing currently used in these parts.

There appears to be green Loctite (or like product) on the inside of the bearing to immobilize it within the housing.

Can anyone here tell me why the bearing would need to be immobilized in this application?

Thanks.

http://forums.pelicanparts.com/uploa...1380188164.jpg
http://forums.pelicanparts.com/uploa...1380188225.jpg
http://forums.pelicanparts.com/uploa...1380188280.jpg
http://forums.pelicanparts.com/uploa...1380188307.jpg
(last photo property of Elephant Racing Products)

Not an engineer but a technician here. Might not be loctite but instead a very viscous grease.(some marine greases are blue /green and sticky to minimise washout during exposed to weather use.) The shock/strut shaft does rotate when you turn the wheel so some type of grease would seem appropriate.
Loctite does make a product to set a bearing or bushing in a housing but I also don,t see why it would be used in this application.

Is the green stuff dried and hard? I would think it's grease.

This is the stuff john's talking about:

Loctite 640:
http://www.henkelna.com/product-search-1554.htm?nodeid=8797924524033

Typically used as a failsafe method to ensure press fit assemblies never come apart unintentionally/ peace of mind if your tolerances are not perfect. Its meant to retain the non rotational component of the bearing- good design practice always constrains the outer race to whatever holds the bearing, and a clamp up method is used to constrain the inner race to whatever moves in order to ensure that the moving part of the bearing does its job. You never want the outer race turning in its mount, or the inner race turning on the through bolt. From what I can tell this assembly would use the retaining compound.... while the bearing is constrained by the snap rings into the housing (it would never fall out), if the whole thing heats up (rear mounts near engine can get pretty warm), the AL housing may expand (faster than the steel bearing OD btw) enough to warrant concern about the press fit being tight enough.

Not enough information to answer the question with certainty and good mechanical engineers don't guess ;)



(ducking for cover and I'm already wearing nomex).

You are not trying to reverse engineer a product made and sold by a long standing and well respected member of the board are you?

sammyg2 - You're spot on.

Why would you do that?

Was wondering the same thing.

Why not just ask Chuck himself.

If he does not want to give the answer maybe the question should not be asked.

I think the answer is here:
http://forums.pelicanparts.com/porsche-autocross-track-racing/764229-suspension-parts.html

He wants to get Chucks designs without actually paying him.

Glyptol
 

I agree with Sammy...Thats why engineers tend to be more conservative. Facts, empirical data and no SWAGs...

But, Just as an observation...and WAG...I would say it looks very much like a staking compound we use in aerospace called "Glyptol" Its a viscus "Loctite" type thread and bearing staking compound. It can also be used as a liquid displacement seal...Meaning; Applied to displace water pooling and saturation in the bearing faying surfaces. As long as the axis rotation and bearing geometry are static and no need for periodic cleaning and maintenance, it can me used as opposed to a viscous grease where bearings are rotational and replaceable.

My .02 cents

Bob

Loctite 648 would be my guess and what I would use

You can get spherical bearings teflon lined, but that doesn't look like most teflon liners I have seen. It still looks like some sort of polymer that the bearing manufacturer injects that solidifies into a solid lubricant. I don't see any staking compound residue on the housing but it would be a belt and suspenders good idea to put loctite there since it sees significant axial loading from the damper and/or coil spring.

You know I saw that thread but the thought never occurred to me.

May be why OP posted in the basement vs the tech forum where Chuck has been hanging out the last 10+ years freely dispensing his knowledge to the benefit of the community.

There is nothing proprietary about that design or protected from an IP standpoint AFAIK. That said, when the OP builds his own parts and they fail he has nobody to blame but himself.

Anyway, it's highly probable that it's green Loctite 640 cylindrical bonding adhesive as others here have said.

Then why doesn't he just ask Chuck? Why ask us? Not like Chuck is hard to get ahold of.

Perhaps because spherical bearings are a wear item, sacrificial, and they timeout after period. Knowing the p/n for the spherical bearing could be a good thing.. Have a spare set it the tool box.... you know, for when you nut and bolt a car and find excess play in a suspension bearing....

We installed a set of spherical banana arm bushings in a car a few years ago... from a "reputable" supplier.....they lasted less than one track season... We tracked it down to the the banana arm bushings when we tried to align the car..... no joy....

Popped out the insert and ordered new from Coast.....

And really.... its pretty easy to reverse engineer many of these type aftermarket products....

He may not know him?

And? His phone number and email are on his web page.

That would be an interesting conversation to listen to:

"Hi, Chuck? Yeah, I am trying to reverse engineer some of you parts, would you mind telling me who your suppliers are? Oh, and the part numbers. Thanks"

I searched the archives here and read a post about monoballs failing and the cause being substandard off shore (made in china) bearings mistakenly being used in the part.

The bearing is pn COM-16 made by Aurora Bearing Company in Montgomery, Illinois. The bearing is a very good, mid line, Made in America, bearing. I wanted to see for myself, the quality of the bearing that is used in this $630.00 set of camber plates.


Thanks Johnsjmc, 86meesta2, Go Dawg Go and all others for your thoughtful input on the "green" Loctite/grease. (I should have added that the substance had turned solid in this application...sorry about my poor description but it never occurred to me that it could be a grease. I guess that's why I came here for input. Lots of brain power/experience in OT.)

and thanks to SammyG2 for your thoughtful caution. ;)

as to "suspension parts" in the Porsche Autocross and Track Racing forum, you can read my comments there for yourself and draw your own conclusions.

I came to OT because the traffic here is 100x higher than in Porsche Autocross and Track Racing. Additionally, I see that SammyG2 and Red-beard have thousands of posts here, and I am almost positive that they are both engineers.

Thanks again.
CalPersFatcat.