Printing a flange in mid position

[stamford]

I have a part with a flange in mid-air, shaft OD55mm one end, shaft OD45mm the other end and the flange OD 90mm in mid-position. Obviously this 90mm flange starts 75mm up from the datum plate. How best to support this to avoid stringing and rough finish? Is it a case of multiple supports or within the 3D design file create sacrificial rings to cut off after printing? I'm fairly new to this and done a few R&D jobs successfully so far including mating threads. Using a Qidi I-Fast, PLA filament.

[airscapes]

I try and eliminate the need for supports at all cost even if it mean multiple parts. I also use a lot of ABS as you can chemically weld ABS.
If supports are used, then you will need to learn what works best, supports are more of an art form then science. My older version of simplifed 3d does fairly well with supports leaving an ok finish that need post processing clean up, but that is part of the additive fabrication process.. However they use a the spacing between supports and part as multiples of layer height so a .5mm layer with large nozzle makes for bad bottom layer over supports. If you can design your own supports try leaving .1mm between the top of the support and the part for better finish assume correct extrusion
Good luck