Ballscrew diy??

[lolailando]

Hi , has anybody tried to fabricate their own ballscrew on a lathe?
It seem from what I have read and asked in the forums that nowadays tooling has replace most of the grinding work, meaning that grinding is only used to get the best accuracy.
Since it is dificult to find long (8'-15') ballscrews cheap, but it is posible to find cheap sort ones in ebay, what about buying the ballnut from ebay and fabricating the ballscrews in a cnc lathe?
It may not be as good as as a commercial one, but it may be still much better than an ACME or a cold rolledand at an affordable price.
Any thoughts?
thanks

[JFettig]

so if you want 8' of ballscrew, how do you plan on cutting it? lets say you get the right threading tool, how are you gonna support a peice that long? if you try to thread part of it and move it along and thread more, its gonna be WAY off.

unless your building a mill, when you get that long you usually would go with a rack and pinion or a belt drive setup.

You can try to fab up some smaller ballscrews on the lathe, they will probably work but wont likely be acurate at all.

Jon

[jimbo]

I have no experience in this area but for an 8-15 foot ballscrew the diameter needs to be quite large to prevent whip and reduce sag, probably 2" or more. I don't believe I have seen a ballscrew much larger than 10' on ebay, at which point rack and pinion becomes better suited. Another option is to use a rotating nut which allows you to get higher speeds and use a smaller diameter screw, but there will still be problems with sag for this length. How will you harden the screw?

sorry, I didnt see Jfettig's post...