B-25 Mitchell Scale Wheel Rims FlightLine

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Scale wheel rims for the FlightLine 1.6m B-25 for use with Robart tires (3.5" Main, 2.25" Front). These rims and tires have been fitted and optimized to fit the B-25. Posting remains a work in progress until after I have some flight experience with these. Link https://robart.com/collections/wheels-scale-wheels-2-4 Motion RC https://www.motionrc.com/collections/main-wheels?filters%5Bbrand%5D%5B0%5D=Robart The OEM main tires measure OD 3.33" and the Robart 3.5" measure OD ~3.53". The increased diameter decreases the clearances to the gear strut and doors. Moving the wheel inboard seems to balance these clearances. Removing the OEM 1.75mm aluminum spacer will create space for the outboard gear door to close. A single washer may replace the spacer. The 3.5" Robart mains looks great on the B-25. The fit to the gear strut and outer door is a bit closer than the OEM tire. The Robart tires have ~2mm clearance and do not interfere on my setup. Main Wheels Options 1) Robart 3.5" Tires on 3.5" printed rims. 2) B-25 OEM Main Tires on 3.5" printed rims. Destructively remove the wheel spokes from 1 side of the OEM rim. Remove tire and trim its ID to approximate the printed rim OD. Posted on HobbySquawk https://www.hobbysquawk.com/forum/rc-airplanes/rc-propeller-airplanes/380695-official-flightline-1600mm-b-25j-mitchell-pnp-thread?p=388746#post388746 3) Robart 3.25" Main Tires on 3.25" printed rims - This rim appears much smaller and spoils the scale appearance IMHO. It should offer greater clearance when retracted. I don't have this tire so it was not fitted to the rim or plane, but I think it should work. Side by side photo of 3.25", 3.5" and OEM is included in the image set. Robart rim measurements 3.5" OD 47mm, W 23mm. 3.25" OD 41mm, W 21mm. Front Wheel Options 1) Robart 2.25" Tire on 2.25" printed G16 rim 2) TPU Tire on 2.25" printed G17 rim, printed G1 tire - my 1st TPU part design. Pretty basic 3) B-25 OEM Front Tire on 2.25" printed G18 rim Build Steps The rims are joined with a tapered hex key and are intended to snap together. Recommend securing the rim halves to each other with glue prior to flight. I am planning to use Clear Gorilla Glue (non-foaming) on the OD of the hex pins and along the rim split line inside of the tire ID. Tool Set P04.STL is provided to facilitate clamp fixtures of the Main and Front rims while adhesive is curing. CAUTION: Radial loads on the rims from taxi, take-off or landing may introduce a force which could separate the rim halves. Use your judgement & appropriate countermeasures to ensure this doesn't result in a wheel lockup or wheel separation from the landing gear. This includes blue thread lock on the axle grub screws. Post Print Steps Finish drill the axle holes before installing the tires. Press the hex pin into one half of the rim. Use a fine felt tip pen to accent the timing marks on the OD of the rims and the hex pin peak. Press the second rim half onto the hex pin. The center-line gap between halves should be very small. Step drill the axle holes 3.9, 4.0, 4.1 mm and 4.9, 5.0, and 5.1 mm. Verify the wheels roll smoothly on the axles. Rims are ready for painting if desired. For tire assembly, align the timing marks on the rim ODs and press/snap the hex key into place. Minor cleaning of the rubber flash on the ID of the tires can reduce interference at the rim split line. Hand stretching the tire while squeezing the rim is an effective way to close the gap between rim halves. A bit of strength and a good amount of persistence is helpful. Use a light to verify the split line gaps are same as when axle drilling was performed. I used a single thin metal washer between the rims and the struts both main and front. The front wheel cap is also snap on/off. Removal is best accomplished by using the mushroom head of the installed OEM B-25 axle to apply force from the inside of the cap.