My tapered rollers have been in for 10 years. I haven't touched them in 3 1/2 years since I installed my els. I pulled the rear when I had the nuts off to install some parts for that and in the prior 6 1/2 years hadn't done a thing. They're fine and still as smooth as the day I installed them and maybe even smoother. ?The preload has never needed adjustment after a couple days of getting it set and my lathe will hold less than .001" over 12 inches. We're talking about bearings meant for vehicle use. Carrying 2 tons and absorbing constant impacts and lasting tens of thousands of miles. I packed mine with synthetic bearing grease. It's still there. Our little lathes turn a couple thousand rpm tops and how often are you running it wide open? ?And how long are you running it? ?We're not talking the equivalent of a hundred plus mile a day, five day a week commute here. We're maybe covering the same as a hundred miles a year, maybe. ?And at a lot less load. The angular contact are probably easier to install from what I've read as there's no need to sand the spindle for the slip fit tapered rollers require but either will last a lifetime with extremely minimal if any required maintenance if property installed.?

On Feb 7, 2025 at 11:04?PM -0500, Jon Rus via groups.io <byghtn5@...>, wrote:

I am on the fence about ACR vs TR,?

Did you get rubber seals on your bearings??

Do you oil them regularly??

Maybe 1 drop before each use?

Does oil leak out the bottom of the bearing or middle of the headstock?

Grease in TR at least is good for a while, maybe even a year before needing repacking like wheel bearings.

How are you working with them day-to-day, project to project??

Thanks in advance

John

On 2/7/2025 7:49 PM, Roy via groups.io wrote:

What this whole thread is overlooking is the fact that the OEM bearings are deep groove ball bearings; the cheapest option! An upgrade to angular contact bearings gives more thrust resistance to the spindle, resulting in the lathe becoming more rigid. Tapered roller bearings would be the most rigid, but, sealing them is much more complex.

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I upgraded mine to angular contact bearings years ago & have been happy with the results! My preload setting method is to simply adjust preload for slight heating at full speed.

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The only benefit to higher precision bearings in the spindle is reducing wallet weight!?

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