Another 12Z owner joining the fold

darkzero said:
Ok but you have servo motors, how about with them? I have no desire to convert myself, just curious cause most say it's not recommended. And if there isn't any problem, I would think there would be a lot more people out there using ball screws on a manual machine.
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That's a good question Will. Without the servomotors adding a bit of rotating mass to the system, I'm not sure what would happen. Maybe someday when I change the drive belts or need to tear into it, I'll try a cut or two and see what happens. Also, I have a 10x54 table, so it's pretty heavy, things might be different with a lighter machine.
 
darkzero said:
And if there isn't any problem, I would think there would be a lot more people out there using ball screws on a manual machine.
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I think you're giving way too much credit to some people. I doubt that 'most' people that say there's a problem base that on first-hand experience running a manual machine with ball screws. But I could be wrong. :)

I liked it on both of the machines I used. Like I said before, I'm not trying to convert anyone's religion here, I just tend to follow my own road and don't pay much attention to what others say unless they are people I know to some degree such that I value their opinion. :)
 
John Hasler said:
Couldn't you just add a drag brake if the machine moves too freely with ball screws?
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Yes probably. I actually prefer resistance as it gives me better control. I'm not knocking the idea of using ball screws on a manual machine. Just curious if they do benefit a manual machine (other than just backlash) & if yes why isn't this something we see more popular.
 
darkzero said:
Yes probably. I actually prefer resistance as it gives me better control. I'm not knocking the idea of using ball screws on a manual machine. Just curious if they do benefit a manual machine (other than just backlash) & if yes why isn't this something we see more popular.
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If you look at my original comment on this, I said that I will be incorporating a quick-release shaft lock mounted at the bearing carrier/end plate. Flip it off, move to your new position, lock it down. Basically the same thing a stepper/servo does.

Like these: http://www.ebay.com/itm/like/371200781235?lpid=82


The ball screw I want will have zero backlash and will wear considerably better than a ACME screw and bronze nut. I'm not going to try to second guess others, but converting to ball screws is not a cheap, nor typically a drop in replacement which might keep many away. Or maybe it's just not something most people think/care about. I'm in that camp when it comes to hobbyist and CNC. Can't figure that one out, but then I write code for a living and want no part of it when I'm making chips. Different folks, different strokes. It's what makes life interesting. :)
 
wrmiller19 said:
If you look at my original comment on this, I said that I will be incorporating a quick-release shaft lock mounted at the bearing carrier/end plate. Flip it off, move to your new position, lock it down. Basically the same thing a stepper/servo does.

Like these: http://www.ebay.com/itm/like/371200781235?lpid=82


The ball screw I want will have zero backlash and will wear considerably better than a ACME screw and bronze nut. I'm not going to try to second guess others, but converting to ball screws is not a cheap, nor typically a drop in replacement which might keep many away. Or maybe it's just not something most people think/care about. I'm in that camp when it comes to hobbyist and CNC. Can't figure that one out, but then I write code for a living and want no part of it when I'm making chips. Different folks, different strokes. It's what makes life interesting. :)
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Yeah, I really don't remember. I'll go back & look later. Really curious & looking forward to your mod though whenever you complete it.
 
darkzero said:
Yeah, I really don't remember. I'll go back & look later. Really curious & looking forward to your mod though whenever you complete it.
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No biggie. :D

This is something that I will likely do early next year after I get the new lathe all settled in. But I will post a project or machine mod thread when I do it.
 
darkzero said:
Yes probably. I actually prefer resistance as it gives me better control. I'm not knocking the idea of using ball screws on a manual machine. Just curious if they do benefit a manual machine (other than just backlash) & if yes why isn't this something we see more popular.
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My guess is, its not more popular because of cost plus how often would you benefit from it. Manufacturing ball screws and recirculating nuts for all three axis vs ACME screws and simple brass nuts way more expensive. Add angular contact bearings vs simple thrust bearings for the ACME screws. The thrust bearings on my mill look like they cost about $1.50. Plus the whole assembly has to be more accurate so you don't put a bind on the angular contact bearings. One advantage is ball screws are a lot easier to keep clean than ACME screws and the ball nut wiper takes care of most of it.

Me personally if my ACME screws and nuts were fine...even though I'm a CNC fan I personally would not purchase ball screws unless I was planning to convert the machine to CNC. I machined a T nut this week to less than +- .001 tolerance using a pair of digital calipers, the dials on the mill, and ACME screws. I see no advantage to ball screws on that job. Maybe if I didn't have a DRO and had to manually machine a bunch of the same part the accuracy and repeatability of ball screws would come in handy.

That's my 2 cents worth.
 
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