While I am quite familiar with the typical steeple back journal brasses, I had never encountered AAR FB journal brasses until I ended up with the ones now listed in the classifieds.

Does anyone know what their use was? Does anyone still use equipment that uses them?

Thanks

Jason Midyette

AAR MSRP D-48 covered the Flat Back bearings. It was revised as late as 1970. I don't have a copy to post. I doubt it would address specific applications, however. I think the steeple back and flat back bearings were subject of a study regarding collar breakage and resulted in the 1970 change in the standard.

Thanks for the info.

Am I correct in thinking that, with the proper wedge, the Flat Back bearings are interchangeable with the Steeple Back bearings?

Are the Flat Back bearings of any use to anyone these days or are they just fancy scrap metal?

Thanks

Jason Midyette

With the correct wedge the two bearing styles are interchangeable. The flat back brass was a superior design and was less likely to run hot. As I recall flat back brass were required in a stabilized box. A stabilized box got an extra six months on the repack date.

Sounds like they are the "Betamax" of Journal brasses.

Guess they are bound for the scrap heap unless someone speaks up soon

Jason Midyette