Originally Posted by HouseOf4Doors
My AM has a lightly glassed interior of the nose and a reinforced motor mount (extra interior struts), always using a balanced prop. Made lots of noise, this terrible "mooing" sound everyone talks about - which bummed me out.
I decided that the best culprit for this sound is the mating surface between the ring motor mount and the 2 mounts on either side of the fuselage, where the thrust-adjust screws contact the 2 mounts. I theorized that the screws were "chattering" against their seats on these 2 mounts. I padded the seat of each thrust adjusting screw with a tiny patch of duct tape. This forms a cushion for the screws, and the result is an absolutely silent, vibration-free airframe.
NO MORE MOO!
I stripped the 2 motor mount screws, so I swapped them out for slightly larger, coarser-thread, wood screws. These screws I believe are stronger and hold the mount and thrust-adjust screws tighter against the now-padded screw/mount seat.
Thanks for the tip. I will try "padding" the screws on mine too. I hate that vibration. I have been trying all kinds of things to get rid of it. I used plywood inside the cowl to strengthen it and balanced my props as well. Same issue from time to time.
I also have a hard time with their "stock" equipment. I think the plane performs best with a 12 inch prop but the stock motor exceeds its current limits with a 12x6 prop.
I is a great little durable airplane that just needed a few tweaks in the design before they released it to be a great airplane.