Ballscrew & Linear Rail Kit - Any Good

[m_c]

Hi gents

Thank you all for the input and did not expect the response to this thread.

You all talk in riddles to me - as i could talk if i started about my industry sector.

I am not sure if i will be using the end bits with the bearings in, as they might not seat within the aluminium profile?

I thought that's what the end plates are for? or am I getting that wrong?

Most kits that i have looked at spec the bearings separately, so naturally assumed that i would not need those brackets (as per the image posted earlier in the thread)

Hope that makes sense

WoodKnot

The machines you're looking at, are designed to be as cheap as possible to build, and will typically use a couple basic thrust bearings to control screw end float. To be blunt, it's a rubbish method, as thrust bearings are hard to adjust accurately in such a setup, and they provide little to retain the screw co-axially, so once it starts spinning fast, the screw/bearings will start rattling around in each other and the end plates.
The BK bearing blocks should use two angular contact (AC) bearings, which get preloaded (aka you can tighten the nuts up so the bearings are loaded, unlike the before mentioned thrust bearings which would just collapse), and provide co-axial retainment of the screw.

Personally, I'd redesign the machines you're looking at, to make use of BK and BF support bearings (BF is just a basic deep groove bearing to support the screw).
The reason the mentioned machines don't use them, is they add cost. They cost more than a couple basic thrust bearings, and you need additional mounting plates for them.

The issue with cheap BK blocks, is it could be a gamble as to what bearings are fitted, the quality of the bearings, and if they're actually fitted correctly.