Linear Rail Bearings

[oskar270]

The attached photo indicates a linear rail with two blocks
http://s285.photobucket.com/albums/l...inear%20Rails/

Anyone knows the purpose of the center set screw? Is it to hold the bearing in place or for some kind of an adjustment?

[morehelium]

I think the center screw is simply to retain the bearing in the housing.

It's not for adjustment, just to keep the bushing from sliding out of the housing.

Chris

[oskar270]

Thank you Chris, it's possible the purpose of this set screw is to hold the bushing in place but I don't think so because the bushings do have on both ends snap rings.

I dont mind to take the bushing out to find out but I was told that I will never be able to put it back again as the balls inside have a certain arrangement and only the factory can do that

[Jaakko Fagerlund]

Either it is for a oil nipple or is there just from the manufacturing process or for something other.

I dont mind to take the bushing out to find out but I was told that I will never be able to put it back again as the balls inside have a certain arrangement and only the factory can do that

Sure, on some high end bearings there is actually some order for the balls, but not in those cheap chinese linear bearings. They use SMA or LM bearing blocks that just have some diameter balls, no order or anything special unless you have ordered them specifically made.

[oskar270]

Thank you Jaakko

[morehelium]

Open bearings like that usually don't have snap rings on the ends and they are hard to see from he pic. It's either for lube or some manufacturers use the same housing extrusion for multiple products.

It won't be for adjustment as force from that direction would flex the extrusion open more than close up the bearing. The only adjustable round shaft bearings I've seen have heavy mounts and screws on the side...

[macona]

Some have snap ring, some have a pin on the end, some have a set screw. Everyone makes them different.

[oskar270]

I have snap rings on both ends but they are hard to see on a picture because they are black like the bushing.

Oil nipple? I will be surprised they installed a set screw instead of an oil nipple. The ball screws have a grease fitting plus I got some spares but nothing for this bearings.

I thought it may be to adjust the play on the bushings? When I install them I will play with this set screw to see I it makes any difference

[macona]

No, They wouldn't put the adjustments where they would be inaccessible when mounted. The rings only retain it within the housing. The set screw probably has a dog point that keeps it from rotating in the housing.

The adjustments for the bearing blocks are usually in the side and squeeze the bearing tight around the shaft.

[oskar270]

No, They wouldn't put the adjustments where they would be inaccessible when mounted. The rings only retain it within the housing. The set screw probably has a dog point that keeps it from rotating in the housing.

The adjustments for the bearing blocks are usually in the side and squeeze the bearing tight around the shaft.

You are right and makes sense

Thank you