Ballscrew from Ebay, what to check first ?

[dart70ca]

Thanks robare, I'll check that out.

kawazuki, thanks for the heads-up but, at the current exchange rate, 70 GBP equals about $130 CAD + shipping. The guy in China is offering the meter-long ones for not much more than $70 CAD (37 GBP) with SHIPPING INCLUDED.

My problem is that I need the fixed and floating support bearings (BK12 and BF12) and his prices on those aren't so good...

Keith

[hignog]

Still a lot cheaper than every place i have seen.
Under half the price as homeshopcnc, and shipping aint that expensive; Would most likey be about £10 to Canada?

Originally Posted by dart70ca Yup, those look just like the ones from China. Being on the west coast of Canada, though, the price is too high coming from Britain. Exchange rate is awful and shipping worse. Is there a North American supplier for these? Keith

[isvflorin]

Uuummm...guys ?

Can you throw your opinion in for the sake of the thread ?
Your past ballscrew experience, old vs new, anything ?

[hignog]

If the quality of the ball screw is not that good, and the ball nut is pre loaded, you may be finding that it is binding.
On a C7 screw the accuracy of the screw is 50 micron over 300mm, if the quality is bad, and infect the accuracy is lower than this, you may get zero or low backlash , but in some parts of the ball screw it will get tight.

Originally Posted by isvflorin Uuummm...guys ? Can you throw your opinion in for the sake of the thread ? Your past ballscrew experience, old vs new, anything ?

[icupeter]

I have bought several ball screws on ebay from a seller in China - yishi_xingtai.
The ball screw quality has been good and I have had no problems dealing with him. He usually ships by EMS. Every week he had about 3-4 new listings. I think all of the ball screws are pulled from semiconductor equipment.

[legendboy]

I have 4 ebay ballscrews I bought recently.

3 NSK C3 and one Tsubaki ground.

They all seem ok, I have taken 2 of them apart and checked the balls/cleaned them up and they move very smooth.

Seem ok to me