open scad is rough unless you are both good with code and already know the basics of a CAD program. I just took a poll
here on CAD softwares. Try OnShape, heard good things, its free and in browser.
I don't have the files you need (well I kinda do, but they are tuned to how my printer worked at the time and have improvements that need to be made), and wouldn't necessarily suggest a wade until after you have your printer working really well. I also am not sure what variant of i3 you have but if it came with the china mk8 extruder i would highly recommend doing what I did and getting an E3D v6 hotend and reusing the tensioner assembly like this:
Most of the problems on a fresh i3 kit, at least from my experience was caused by the hot end, that extruder and tensioner assembly actually was very reliable and didn't replace it until I went to a bowden set up
Edited 3 time(s). Last edit at 09/18/2016 11:07PM by DaGameFace.
If you need some help, or don't understand what I just said, feel free to send me a PM anytime
Printer: Prusa i3, 2 E3D v6 Hotends, Arduino + RAMPS 1.4 with a Bypassed 5V Regulator, 400w Insignia ATX PSU, Custom Designed Bowden Extruders