F-35 RC Airplane Flex Brace for Nose Gear Freewing 70mm EDF

thingiverse

The Flex Brace was installed on a brand new F-35 and has been flown 10 times so far. One bad landing managed to break the main gear mount, but the front gear/nose was entirely undamaged. The flex brace performed exactly as expected. Subsequent crash this aircraft also exhibited excellent performance of this brace. The setup included additional nose gear spacers to raise the nose by 7mm.This Flex Brace is an alternative to the typical rigid nose gear supports. It makes use of the elastometric properties of polymers and the shape forming capability of 3D printing. The web thickness of the Brace 'spring' and type of filament will both affect the stiffness/reaction force. If you want to support my contributions here, please consider leaving a tip https://www.paypal.com/paypalme/ShowmethedenaroOverviewDesign intent is to better distribute the aft and lateral forces on the nose gear between the 1) gear primary structural support , 2) fuselage foam on the perimeter of the brace Potential benefits include1) Improved nose gear & attachment durability2) Reduced damage to fuselage foam on the perimeter of the brace compared to typical rigid supportsFor the F-35, I also added two spacers to increase the nose height by 7mm to improve the takeoff performance. The 4mm nose gear spacer https://www.thingiverse.com/thing:4529124 sits under the retract servo. The 3mm nose strut spacer sits on the strut between the trunion and the oleo.The nose gear strut pin was modified as follows to accommodate the 3mm nose strut spacer. Extend the length of the OEM flat on the strut pin to leave a 0.5mm shoulder to the end of the pin.Add a flat 180deg opposite the OEM flat on the strut pin.Eliminate interference of the nose gear grub screws with the Flex Brace. Shorten both grub screws by removing ~0.7mm from the contact end.Note: The Freewing Stinger 90 Nose Landing Gear Connecting Pin (SKU: FJ30511085) is purported to be an ideal replacement for the F-35 with spacers.CAUTION: Filament selection is key for success with this design. I have found Polyamide (PA, Nylon) filament is more capable of handling the large deflections required for this design. Consider operating temperature range when selecting filament. Some polymers become brittle at low temperatures and could fail with 'normal' deflections. Some soften with increased temperature which could affect performance.The design is intended to be adhered to the fuselage on the entirety of the Brace perimeter. Select an adhesive which is appropriate for the foam and filament. My preference is FoamTac if the filament is compatible. Clear Gorilla Glue is my 1st alternate.See my other Flex Brace postings on Thingiverse for additional background information.