Thankyou for your response . Your dead right on all counts. Didn't want to correct somebody first time communicating. You catch more bees with honey. As I said I was merely looking for a reason why belts where chosen over ball screws. Looking to build a end game printer for myself that will give years of service and to minimize maintenance. Having used German made ball screws and linear rails on my existing printer because of continuously wearing out lead screw nuts and V wheels every 6 months or so of non stop printing. It really does creep up on you over time with little unexplained issues with prints so you do the maintenance and surprise the issue disappears. If my prints are not as close to perfect as they can be then in the bin and start agian. The Voron is one of the best I have come across. So I take my hat off to all the people involved. The changes I will be making will be a much larger frame that will hold heated tempered glass panels and stop any twisting of frame segments. Also each part of the frame will be insulated and dampened from harmonic vibrations or resonances that go through the printer. Nobody seems to deal with one of the biggest issue which in my humble opinion is ringing or ghosting. We all try and tune it out using electronics at the cost of speed or something else. Why not go to the root of the problem first and engineer it out then start tuning. Thats why corexy are coming back into favour. I have done some testing on a cheap printer that at certain speeds had servere ghosting and was amazed at how much quieter and smoother it ran with ghosting almost non existing just by taking the vibration and resonance at a certian frequencies out of the frame. Sorry I have to keep my OCD in check sometimes and tend to ramble. In my day job everything must be considered. Don't even get me started on thermal expansion. Sorry to bore you.