Linear bearing alignment vs radial load

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hobgobbln
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Linear bearing alignment vs radial load

Post by hobgobbln »

I've got to build a mechanism for a guy and was planning to use a linear bearing. Doing some research as I've never built anything with them, I'm not seeing any radial load specs, but all sorts of warnings about misalignment.

I'll throw some pictures of a super high end example of the motion I'm looking for ( :lol: ) Basically it's the same idea as a cylinder in an engine except the piston extends through both ends of the cylinder. The copper pipe would be a shaft with a roller on the left end that will run against a cam. The white piece of tubing it's riding in is where I wanted to use the linear bearing. The angle bracket will pivot at it's elbow and the black piece would be pinned at both ends to act like a connecting rod.

Reading the specs on the linear bearings at McMaster, they mention static and dynamic load ratings but not the direction. They also list whether the bearings are fixed alignment or self aligning and the degrees of misalignment. In a configuration like this will the linear bearing resist a twisting force or will it just disintegrate? This will be super low speed and relatively moderate force.

Griz
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NP317
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Re: Linear bearing alignment vs radial load

Post by NP317 »

The joint where the black rod connects to the angle bracket will require a slot to accommodate the radial movement induced by the bracket.
Alternately, add another link between the rod and bracket that moves like a locomotive main rod and crosshead.
RussN
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Bill Shields
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Re: Linear bearing alignment vs radial load

Post by Bill Shields »

Copper pipe?

Not very stiff...
Too many things going on to bother listing them.
hobgobbln
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Re: Linear bearing alignment vs radial load

Post by hobgobbln »

I am not using anything in the pictures. My CAD skills are minimal and didn’t feel like spending a day figuring out how to model that.
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Bill Shields
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Re: Linear bearing alignment vs radial load

Post by Bill Shields »

Ah....ok....know that situation
Too many things going on to bother listing them.
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