Bearings

[Triumphman]

I'm using the wrong type.
I've got a pillow block mount bearing holding a sprocket for a chain tensioner, but as these are self aligning, it's pulling over under the tension of the chain.
What bearing should I use? Ideally mounted in the pillow block.
Thanks

 

[WorkshopChris]

Morning and welcome,
Could you modify to use Angular Contact Bearings, ideally you want to look at Thrust bearings.
Have you adjusted the chain sprockets to be perfectly inline with each other.

 

[rtbcomp]

As the load will be sideways on I would have thought a standard ball race would do the job. Thrust bearings are designed to take an end-on load.

 

[Fazerruss]

Are you using 1 block or two parallel to each other?
Some bearing blocks are no good resisting lateral forces if they are pressed steel type and the bearing moves in the block slightly.
Two would be my choice.
Any pics of the set up?

Edit. Just noticed you mentioned self aligning so I guess its skewing.
If possible fit another next to it with shaft going through both.

 

[knighty]

yeah, you really need two bearings, and the further apart the better

(even better if there's one each side of the chain)

as long as you've got two, self aligning is better :-)

 

[rtbcomp]

For something as simple as a tensioner I would use one standard ball race pressed into the sprocket so that the teeth on the sprocket line up with the centre of the bearing and mount the whole thing on a swinging arm, a bit like you see on bicycle gear changers.

If you have to have the sprocket some distance away from the bearing then the Fazerrus/Knighty methods should be used to prevent twisting forces in the bearing, although you may get away with a wide roller/needle bearing, all depends on the forces involved.