HI, this is my first scale build and wanted to share some pics and a flight video. I think some of the information I can post here will help others with building similar birds. I bought the kit from MotionRC last October. I went slow with the build and made sure to get everything correctly built. one of the things I spent more time on was the Gear mesh for the umbrella gears for the TT. I went as far as to match the gears with one another. See every umbrella gear in the kit has a tiny wobble or high and low spot. If you match one gears high spot with the other gears low spot, you have to gears running in harmony and now can get the mesh as close as possible with the included shims without binding. After about 2hours of flight time I cleaned the gears regressed and sealed both front and rear gear boxes with 3d printed covers. They now have over 2hrs covered and almost 5hrs total flight time.
I did have one mayor setback while building the mechanics. The big belt pulley the 78T aluminum belt pulley was making the belt vibrate. This was caused from the incorrect milling of the teeth. The pullies teeth were milled offset causing the belt to tighten and loosen every rotation. I got in touch with MotionRC and had to walk over egg shells for them to believe me. Even with videos showing the defect on the pulley. After many videos and hours They still did not believe me but, still decided to send me a new pulley. When I saw the confirmation email, the pulley they were going to send was the incorrect one. Turns out MotionRC does not carry the pulley and never have. Instead they gave me store credit for my next purchase and I had to order the pullet directly from Roban in China. This took over a month.
While building there were a few minor thing that I did have to go over. One was the TT is was not very straight. I had to straighten it I wanted to use it, this was done gently by hand with a dubro balancer the 2 TT bearings and a marker. When I finished the tt was perfectly true on the boom. You could take of the tail box and spin the head to the the TT and it would have zero wobble. I also pinned the TT by drilling a hole and press fitting a 2mm pin. Another thing that had to be fixed was that the tail shaft was bent. The bend was enough to notice my pitch slider wobbling when turning the head by hand .I also had to bend this straight with some small pipes I used as tools. the end result was a perfectly straight tail shaft.
I did disassemble the mechanics and went over the whole thing. All my screws were Loctite with a very strong brand. I can assure you that nothing was going to come loose. I did make a test rig to make sure everything worked fine before putting them in the fuse and, did over 2hr flight time on the test rig. I was very impressed with the mechanics. The SM2.0 mechanics look great. They are also built very rigged and, the fitment is excellent. Then only part I did change was the plastic ball links to SAB 700 plastic ball links. I did keep the Roban balls.
The fuselage, this is were the kit really shines. The model is huge (I included a picture next to a 700 Goblin) and the paint is flawless. This kit also includes so many details and full interior. The only mod here was that the hole for thee landing light was made to far up. It actually looks like they made the hole for the fresh air vent hole and forgot to make the hole to mount the landing light. I used a dremel and made the hole in the correct area and installed the landing light. I am also using the included lights with a 5v bec to feed the led controller.
The main blades were the only disappointment for me. They were all balanced writhing one gram and the CG of all 5 blades were very close 1-2mm. The problem was they were not straight, and were also twisted. One blade was straight, two were bending upwards and, the other two were bent downwards. I fixed this by placing the blades over 2 blocks with weight in the middle to bent them straight. I left them like this outside in the hot sun and eventually got al the blade straight. Then I notice when I used my pitch gauge the the pitch would move up to 0.7 degrees on the worst blade. This was fixed by sanding the blade hubs at different angles an matching the grips with the correct blades.
So far I am very happy with the kit and would buy another one. The only thing that has failed in the kit was the shaft the the One way bearing rides one. I do have to admit I was flying it very hard with the test rig to make sure if something broke it was before I installed the fuse. This part was not available at MotionRC so I made it from a sab 700 feathering shaft.
I did have one mayor setback while building the mechanics. The big belt pulley the 78T aluminum belt pulley was making the belt vibrate. This was caused from the incorrect milling of the teeth. The pullies teeth were milled offset causing the belt to tighten and loosen every rotation. I got in touch with MotionRC and had to walk over egg shells for them to believe me. Even with videos showing the defect on the pulley. After many videos and hours They still did not believe me but, still decided to send me a new pulley. When I saw the confirmation email, the pulley they were going to send was the incorrect one. Turns out MotionRC does not carry the pulley and never have. Instead they gave me store credit for my next purchase and I had to order the pullet directly from Roban in China. This took over a month.
While building there were a few minor thing that I did have to go over. One was the TT is was not very straight. I had to straighten it I wanted to use it, this was done gently by hand with a dubro balancer the 2 TT bearings and a marker. When I finished the tt was perfectly true on the boom. You could take of the tail box and spin the head to the the TT and it would have zero wobble. I also pinned the TT by drilling a hole and press fitting a 2mm pin. Another thing that had to be fixed was that the tail shaft was bent. The bend was enough to notice my pitch slider wobbling when turning the head by hand .I also had to bend this straight with some small pipes I used as tools. the end result was a perfectly straight tail shaft.
I did disassemble the mechanics and went over the whole thing. All my screws were Loctite with a very strong brand. I can assure you that nothing was going to come loose. I did make a test rig to make sure everything worked fine before putting them in the fuse and, did over 2hr flight time on the test rig. I was very impressed with the mechanics. The SM2.0 mechanics look great. They are also built very rigged and, the fitment is excellent. Then only part I did change was the plastic ball links to SAB 700 plastic ball links. I did keep the Roban balls.
The fuselage, this is were the kit really shines. The model is huge (I included a picture next to a 700 Goblin) and the paint is flawless. This kit also includes so many details and full interior. The only mod here was that the hole for thee landing light was made to far up. It actually looks like they made the hole for the fresh air vent hole and forgot to make the hole to mount the landing light. I used a dremel and made the hole in the correct area and installed the landing light. I am also using the included lights with a 5v bec to feed the led controller.
The main blades were the only disappointment for me. They were all balanced writhing one gram and the CG of all 5 blades were very close 1-2mm. The problem was they were not straight, and were also twisted. One blade was straight, two were bending upwards and, the other two were bent downwards. I fixed this by placing the blades over 2 blocks with weight in the middle to bent them straight. I left them like this outside in the hot sun and eventually got al the blade straight. Then I notice when I used my pitch gauge the the pitch would move up to 0.7 degrees on the worst blade. This was fixed by sanding the blade hubs at different angles an matching the grips with the correct blades.
So far I am very happy with the kit and would buy another one. The only thing that has failed in the kit was the shaft the the One way bearing rides one. I do have to admit I was flying it very hard with the test rig to make sure if something broke it was before I installed the fuse. This part was not available at MotionRC so I made it from a sab 700 feathering shaft.
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