Topic: Thingiverse "Threadless Ballscrew" - Customizable (level 2 - Techie)
This is an openSCAD adaptation of http://www.thingiverse.com/thing:112718. I added a few options like ability to add more than 3 bearings, variable bearing size, variable smooth rod size, customizable mounting holes and more.
You can preview the file using the Web Viewer.
The customizer will work for Solidoodles however, the script can be altered to work with all types of mounting solutions. See below for help selecting standard bearing sizes. Your bearing nut size is whatever size screw need to hold the bearings.
I won't be uploading this to thingiverse until Wednesday at the earliest. I am still waiting on a few parts. I just wanted to get this up here in case anyone felt like testing it out.
Suggested Print Settings:
* .15 mm layers or smaller
* 3 perimeters minimum
* 100 percent infil*
*There is a lot of force on the bearings and corresponding bolt. I have observed that over time, the heat will build up and cause the bearings to get looser. Also, the plastic will flex and degrade if the infil is too low. The bolts that hold the bearings in need to be very tight. In order to tighten the bolts up with out the nuts ripping through the plastic, you need to have 100 percent infil.
Standard bearing sizes that this will work with: (list derived from Bearing Works)
PN ID OD Width
603 3 9 3
604 4 12 4
605 5 14 5
606 6 17 6
623 3 10 4
624 4 13 5
625 5 16 5
626 6 19 6
633 3 13 5
634 4 16 5
635 5 19 6
636 6 22 7
673 3 6 2
674 4 7 2
675 5 8 2
676 6 10 2.5
684 4 9 2.5
685 5 11 3
686 6 13 3.5
693 3 8 3
694 4 11 4
695 5 13 4
696 6 15 5
Note: The band at the top of this picture is due to some heat build up. That is the first solid layer and it tends to warp for my if I don't have a fan. The cylinder behind this did not exhibit the same degree of banding which leads me to believe it isn't mechanical. 
Glass bed with QU-BD heat pad upgrade, threadless ballscrew w/ 8mm smooth rod, spectra line belt replacement, lawsy MK5 extruder, Lawsy replacement carriage, E3D hotend, Ramps 1.4 w/ reprap discount controller, DRV8825 drivers, 12v 30A PS, Acrylic case, Overkill Y-idlers, Filament alarm, Extruder fan + more.
. 
We basically have to calibrate everything anyway 
