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Gallery, Projects and General => Project Logs => Topic started by: davidcurtis021 on June 08, 2017, 10:27:47 PM

Title: bearing change
Post by: davidcurtis021 on June 08, 2017, 10:27:47 PM
about to change the headstock bearings in the mini lathe, when i rang to order taper roller type bearings, the supplier reccomended chosing angular bearings instead anybody got any thoughts on this.
Title: Re: bearing change
Post by: Lew_Merrick_PE on June 09, 2017, 01:18:48 AM
about to change the headstock bearings in the mini lathe, when i rang to order taper roller type bearings, the supplier reccomended chosing angular bearings instead anybody got any thoughts on this.

David -- Angular Contact Ball Bearings have lower friction (though greater Hertzian Contact Stresses) than Tapered Roller Bearings.  Thus, except for Spindle Broaching types of operations, they (Angular Contact Ball Bearins) have fairly good axial load capabilities and lower overall friction.  The question really is, What kind of axial load do you need?
Title: Re: bearing change
Post by: Roger B on June 09, 2017, 02:25:40 AM
Both options are better than the original bearings. If I remember correctly the angular contact bearings don't require the spacers to be modified.
Title: Re: bearing change
Post by: Peter Cordell on June 09, 2017, 04:46:05 PM
Did this on my CJ18A  "taper rollers" did not fit the shaft difference in dimensions damaged the shaft, plus seals are a problem
this cost me a new shaft, so went with angular contact bearings
Looking back i think the original bearings where just as good
Title: Re: bearing change
Post by: velocette on June 09, 2017, 06:52:15 PM
Hi all
Perhaps these PDF File Is Useful for you.
 Thanks to Arceurotade.co.uk I have no connection with this company only know it from reading of  it on other forums.
Please be aware that Taper Roller Bearings are 17.25 mm wide and the Angular Contact Bearing and the Ball Bearing are 16 mm wide.
I Converted an X2 Mill Drill to Taper Rollers and Poly Vee Belt Drive With no problems. 

Eric
Title: Re: bearing change
Post by: John Rudd on June 11, 2017, 11:35:50 AM
Did this on my CJ18A  "taper rollers" did not fit the shaft difference in dimensions damaged the shaft, plus seals are a problem
this cost me a new shaft, so went with angular contact bearings
Looking back i think the original bearings where just as good

Shame I did not hear of this earlier.....
Ben, the spindle on the mini mill/lathe is designed for standard ball races, and as such are an interference fit on the shaft and housing.
Taper rollers are designed for a slidibg fit on a shaft with an interference fit in housing.
When I change both of my machines to tr bearings, I used wet n dry paper to polish the spindles for a tight sliding fit of the inner races to ensure the bearings would preload on assembly.
Title: Re: bearing change
Post by: seadog on June 11, 2017, 05:51:53 PM
On my Boxford they're not John. Had a hell of a job dismantling the spindle.
Title: Re: bearing change
Post by: davidcurtis021 on June 12, 2017, 03:57:26 PM
well i did lots of research read your comment's and sought the opinion of good friend's and i decided i'll go with the taper roller option, but at the same time i'm investing in a new 4 inch spindle.