BABBIT BEARING

[farmall666]

WHAT IS THE DUFFERENCE OF A BABBIT INSERT BEARING TO A REGULAR INSERT BEARING...

[1967806]

I always thought all insert bearings had some babbit on them. Like the grey material before it gets in to the copper? But then on the old stuff they poured babbit in a lot of bearing journals. 

[KWRB]

If I was home, I'd share the section of Marks Handbook that discusses babbiting.

Anyway, babbit is that gray wear surface of steel non-rolling-element bearings.

There's nothing clear about what the difference would be, just from those descriptions. It could possibly be that one bearing is babbit and one is rolling element... Could be babbit versus bronze etc.... Could be that the ones they're calling "babbit" are different in that they're re-babbited (new wear layer disposed on existing substrate).

Could be anything, but it's not clear from the description. I'd be calling the manufacturer.

[mjcolemn]

Way before my time... but whenever I've heard reference to babbitt bearings they were talking about poured in bearings. 

[oleman]

Babbit is either cast or plated onto bearing surfaces. 

Cast Babbit bearings were widely used in the auto industry until the early 50's. The Chevy I6 built before 53 had cast babbit bearing connecting rods journals. The bearing surface is heated and poured onto the parent part and then machined for tolerance, the old Chevy used steel shims to set initial tolerance. The first engine I everhauled was a 51 Chevy 216 with cast babbit

Babbit is a very soft material that  wears quickly but is very forgiving in tolerances and lubrications.

The main shaft on the USN ships I was on had cast babbit bearings for mainshaft support. Those shafts are very heavy and rotate at a relatively slow speed, (several hundred RPM max) Our engineering gang replaced one on a mainshaft undeway at sea

Plated babbit bearings are shell bearings with a final babbit surface,  I am thinking that all out race engines would be a good application for this type.

The Georgia Museum of Agriculture has a website on youtube (Keith Rucker is the host) that has a lot of video on cast babbit bearings, I have learned a lot over the past 10 years by attending their sessions.

[kevinj]

On 5/7/2022 at 10:36 PM, farmall666 said:

WHAT IS THE DUFFERENCE OF A BABBIT INSERT BEARING TO A REGULAR INSERT BEARING...

Inserts are removable and typically have Babbitt over a steel shell. So I think you are just looking at a difference in terminology.

[Ian Beale]

4 hours ago, oleman said:

The main shaft on the USN ships I was on had cast babbit bearings for mainshaft support. Those shafts are very heavy and rotate at a relatively slow speed, (several hundred RPM max) Our engineering gang replaced one on a mainshaft undeway at sea

A neighbour got the story of how they do that from an ex-Navy bloke.  You have to stop the bearing metal sticking to the shaft, so the shaft was painted with a mix of lamp black and wood turpentine.

We had to re-bearing a bore pumphead shaft which had the bearings poured in eyes in the cast frame.  You set everything up and then pour in place.  We used one of the modern dry coat sprays on the shaft and it did the same.

[hardtail]

Recall my buddy working in an engine shop in the early 80s and I think the Chevy dealership had them do some engine work on warranty and then called back to the shop about some problems they encountered with cam bearing fit, boss send my buddy over with some special scraper tools to achieve the proper tolerance, the dealership mechanics were horrified to see the precision work take place 😲 never came back as warranty not sure if it affected how many future jobs they sent their way after, he has quite a few good stories from those days 😊