Ballscrew & Linear Rail Kit - Any Good

[JAZZCNC]

Relax Jazz, I am not exactly disagreeing about the differences with you or others, but as you say, it's about costs, so it is a compromise.

I'm 100% relaxed Camera but this isn't about costs at all, it's about what is suitable and what's not and those BK bearings with deep groove bearings are not suitable for a CNC machine because they are not designed to handle the loads in an axial direction. It completely defeats the point of fitting ball-screws if the end fixings are allowing the screw to float which they will with these deep grove bearings unless they are highly preloaded and it's this high preloading they are not designed to handle so they quickly wear excessively which in turn put stress on other parts of the machine. It quickly becomes a vicious circle of wear and stickiness.!

Regarding experience, I should actually ask the same... because honestly, if you have such low views on those BK/BF bearings then I have to assume that you don't use them. On the other hand, I am waiting for the 10th, so yes, I must claim that I have some experience with them, more than you think. OK, only for 1605 and 1204 screws, but none the less... I was not born yesterday just because I ask some questions occasionally.

You are correct that I don't use these and never would, but I do have lots of experience of replacing them and helping other people who have unwittingly bought these, and the number is far more than your measly ten.!
In terms of experience fitting BK/BF bearings in general then I buy them by the 100 and just today I've fit 8 sets so you could say I know a little about them.!!

Anyway, I am NOT saying that those bearings are as good as AC bearings. What made you believe that? All I am saying is that he should wait and see and decide on his own for the final decision. Of course it's good that the alternatives are clear and drawbacks are highlighted, but as been said before, replacing the bearings is easy and can wait. But then again, if replacing means complete redesign of bearing seats to fit AC bearings then it is a huge job for an amateur and also a large one for a pro. It's also a hobby machine, so aiming for something reachable is better than aiming at the stars and never get there.

First of all, I didn't think you thought they were as good and never implied that you did. My objection to your comments is solely based on the fact that you advised the OP and advocate to others the use of Deep grove bearings for BK bearings was perfectly fine, they are NOT.

The other thing I don't agree with or understand is why anyone would buy these knowing they are poor quality or in this case plainly wrong and pay again to make good.? Crazy to me when for not much more you can buy the correct BK bearings.


On another note, I also feel you owe Clive S an apology because his comment was a valid one, even if it was short and to the point, your attack on him personally was unjustified and out of order in my opinion.!..