New Bearings/races too big?

A forum for discussing issues relating to trailers and towing MacGregor sailboats.
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glasshopper77
Posts: 9
Joined: Wed Jun 10, 2020 12:22 am
Sailboat: MacGregor 26M

New Bearings/races too big?

Post by glasshopper77 »

Hi everyone,

Just got new bearings from BWY. I removed the old races and bearings from hub no problem. I then tried to install the new races but they are SUPER tight! I even had a buddy of mine helping me who has tons of bearing experience and he says "something about those bearings just isn't right".
You can line up old and new races on top of one another and notice the new one is just slightly bigger....

Old race has # L68110
New race # L68111

Oh and I have a 2010 :macm: with the aluminum trailer.

Thanks
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Tomfoolery
Admiral
Posts: 6135
Joined: Tue Jul 05, 2011 7:42 am
Sailboat: MacGregor 26X
Location: Rochester, NY '99X BF50 'Tomfoolery'

Re: New Bearings/races too big?

Post by Tomfoolery »

That's because the new race has a 0.034" larger OD. Wrong race. Not even close. A thou or two extra would be a lot when talking about interference fits on something that small*, but 34 thou might as well be an inch bigger, as it isn't going in, and if you forced it with a press, the actual tapered race would be distorted beyond use.

Better call BWY about it, or source the bearings elsewhere. :|

*I do a fair bit of design involving rolling element bearings, and fits and tolerances are normally brought out to the fourth decimal place in inches, or tenths of thousandths of an inch. And the machinists we use don't bat an eye, as it's not at all unusual.
Tom
Be seeing you . . .
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