X axis drive

[JAZZCNC]

While I bow to your experience Jazz, and I do know that my knowledge of this machine is limited to what I see on those pics . Never seen one in the flesh, Never used one.
But having replaced leadscrews with ballscrews in a different application, I found it no big deal , and it looks to me as if a BF on the outer end of the leadscrew/ballscrew would at least eliminate any end float in that screw without being a challenge to mount.
I dont see enough detail in the crosshead pics to know what is in there but it is hard to believe that an adaptor for a ballnut could not be accommodated. and £ 30 or so is not a massive outlay to keep the machine running reasonably while Petesos (like me ) continues his learning process.

No need to bow to me and all suggestions are good but that doesn't mean they are correct. This machine won't accept a BK type bearing easily and would severely limit the travels etc and the price is going to be much more than £30.!
As I see it without the tools to modify the end bearings to accept a ball screw designed for a BK setup the only sensible solution is to replace the screw with one that as been machined to the same end fittings, which is why I said contact Fred at BST. He will machine to any drawing you provide and at hardly any extra cost but it will still be much more than £30.
Other option is to do like been suggested and stick with lead screw and try to source one local.!

End of the day you have to decide how much backlash is acceptable. I would also question where the backlash is coming from because I'm sure I've seen +1mm mentioned and I'd be very surprised if all that is coming just from the screw/nut.? in which case replacing with ball screw won't get rid of that and that is my point about these machines. When you step down this upgrade path you open a can of worms with the only result being wasted time and money. It will always be a PIG with Lip stick on.!

[John11668]

I get all that you are saying jazz, and i agree that petesos would be better placed if he had a better machine , but it seems to me that in his current circumstances it could be not too hard a job to fit ball screw and BK nut. From what I see the BK bearing could be bolted to the outer face of the cheek, with a ball screw fitted through it and secured with the preload nut outside that. The motor end would need shortened and maybe reduced depending on the coupling size , and while there would be no easy place to fit a BF Bearing the fitup would be no worse than it is now with no support.
Yes he needs to ensure that the backlash is not occurring due to a slack fit at the coupling but that should be easily visible and remedied
What we would need to establish is whether the bore retaining the existing crosshead nut would accommodate a 12-04 ball nut, https://www.bing.com/search?q=1204+b...ANNTA1&PC=U531
and dismantling to check this should not be a hard job .

[JAZZCNC]

I get all that you are saying jazz, and i agree that petesos would be better placed if he had a better machine , but it seems to me that in his current circumstances it could be not too hard a job to fit ball screw and BK nut.

Well first off it's a BK bearing block, not a nut and I'm not sure what cheek you are referring to.? But anyway it doesn't need to be that difficult if he gets a ball screw machined to the same dimensions as the old screw.

My point was the screw you linked won't just bolt straight into place so it will need more components meaning more cash, it will need some modifications to the machine and if the OP doesn't have the equipment or the experience to do these mods himself then it's not worth paying someone else to do them or having new parts made so it can be upgraded because the machine is what it is and throwing money at it won't make it change from a PIG into STALLION.! . . .It will always be a PIG with lipstick.!

Anyway, I've said my piece on why I think it's a bad route to take based on my experience with these machines and seeing other users make the same mistakes and we obviously won't agree so let us leave it at that and let the OP get on with which route he thinks suits him best.!