This is a simple FPV race gate that I drew up in Sketchup.  

I have a much heavier duty modular FPV gate (cube) here if you are interested:

Modular FPV Drone Race Gate - Free 3D Print Model - MakerWorld

Each segment is 175MM long so it will fit on the A1 plate.  You will need to print 8 segments for each hoop.  They push together with just enough resistance to stay in place but are very fast to take down/set up.  I used squares as the attachment points so the octagon won't sag as the angles are set.  The inner square is 5MM and the snap in square is 4.9.  It prints perfectly fitting on my A1 mini in PLA.  Note that I chose the standard .2MM height setting and default infill but did override the walls to 3 to give it a little more strength.  I suggest printing just two segments and test fit before committing to a tray full in case your printer doesn't like the tight tolerance.  One stand will suffice but a second is a little more stable.