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wierdscience
02-26-2011, 10:26 PM
Started working on my T&C grinder this week.First up was the motor,that checked,next were the spindle bearings.
They were rough as a cob so replacements were needed.Spent a couple hours disassembling the spindle and found two Fafnir MM9105 bearings inside.Angular contact ball,phenolic cage outer races marked "Thrust" 15* contact angle.

Popped out my Fafnir catalog,looked up MM9105,still make them,great I'll order a set-wait a minute.

Part number is now a MM9105K,look up what is K? K is Conrad type ball bearing,not my bearing:confused:

Looked a few pages over,it's now a 2MM9105WI:rolleyes: $189.00 ea.:eek:

So once again we have seen ,never,ever order a bearing by it's numbers only.

I did find a set of Nachi 7005CYDUP4 for $220.00 out the door,much better:)

Carld
02-26-2011, 11:42 PM
It's got so bad even though I look them up in a catalog I still call the bearing supply house to be sure of what I am ordering is right.

Can't they just leave things alone and not change the numbers every year or so.

philbur
02-27-2011, 04:55 AM
Is it possible that the manufacturer intends for them to serve the same function. Hence the same number, with a qualifier.

Quote from Wikipedia:

"Conrad bearings have the advantage that they take both radial and axial loads, but the disadvantage they cannot be filled to a full complement and thus have reduced load-carrying capacity compared to a full-complement bearing."

Seems to me that potentially the only effective difference is the actual load carrying capacity, which is not an issue with a T&CG.

Phil:)


Popped out my Fafnir catalog,looked up MM9105,still make them,great I'll order a set-wait a minute.

Part number is now a MM9105K,look up what is K? K is Conrad type ball bearing,not my bearing:confused:

macona
02-27-2011, 05:02 AM
As far as I know Konrad is a fancy name for angular contact.

lazlo
02-27-2011, 09:36 AM
As far as I know Konrad is a fancy name for angular contact.

Conrad means deep groove radial bearing. It can take axial and radial loads in either direct.

Darin's 9105/7005 is a thin section angular contact bearing. The 9105K is a Conrad == deep groove radial -- you don't want it :)

wierdscience
02-27-2011, 11:21 AM
Conrad means deep groove radial bearing. It can take axial and radial loads in either direct.

Darin's 9105/7005 is a thin section angular contact bearing. The 9105K is a Conrad == deep groove radial -- you don't want it :)

Yup,not the same crossection at all.

CarlD,worst yet are oil seals,everytime one company buys another they feel the need to change the nomenclature,royal PITA.