You must Sign-in or Register to post messages in the Hobby Squawk community
Registration is FREE and only takes a few moments

Register now

Announcement

Collapse
No announcement yet.

Roban 800 size Bell 222

Collapse
X
Collapse
First Prev Next Last
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Roban 800 size Bell 222

    Didn’t see a thread out there for the 222, so here one is. Last year, I acquired an NIB Mercy Air Bell 222 off of the other forum that a user had purchased new from Motion. It sat on the bench until a month ago. Over the last few weeks, I have gotten it assembled and in the air. Overall, I’m pretty pleased with it, but there are a few things to watch in the build.

    Components in the build were:
    Motor: Align 800MX 520KV
    ESC: HobbyWing 130HV
    Servos: Xpert R2
    FBL: Ikon2 BT

    No pictures from the build unfortunately, but here’s a list of the mods, issues, and changes that I’ve run into.

    1. Retracts - The stock arrangements work fine, but are a bit complex. Be very precise on the setup! The bellcrank should not be imparting any torque to the retract on-ground. That load should be going through the wood stops that contact the struts. I would also recommend reinforcing the wooden tray that hold the main retract units. In its stock configuration it cracks fairly easily. I added a small 1/4” plywood doubler over the perimeter of the retract box where it meets the tray.

    2. Tail Rotor Direction - this was not scale for a 222 in the stock configuration. In addition, it can also be less efficient and have slightly less control power. I elected to change this so that the inboard blade rotates up into the rotor wash. This was done fairly easily by relocating the upper tail rotor bevel gear to the lower side of the shaft. I also pinned the torque tube to prevent this from unscrewing the threaded ends.

    3. Light controller - the Roban light controller gave me a bit of trouble at first. Initially, I had it on a Y harness with the BEC input and the flashing pattern seemed to change with every boot. I relocated it to the bind plug and it’s worked fine ever since.

    4. Paint - the paint quality is good, but one of the critical paint lines is off in position. Normally, this wouldn’t be a huge issue, but it would cut straight through the large MERCY AIR decal that goes on the sides of the aircraft. I’m still trying to figure out what I’ll do there. Either I will order some smaller letters that fit in the white area, or I will squish together the existing letters a bit. Minor gripe, but the tail number is also incorrect. The included numbers correspond with a skid gear 222. N408MA or N406MA would be more correct.

    5. Mods-to-come: Blade paint, Medical interior, wire cutters, and searchlight.

    Overall, the aircraft flies very well. I’m currently governed to 80% to keep good tail authority. It is quite stable and well behaved even in winds. With the low tail clearance, a slight rolling takeoff and landing are recommended if possible. Attached are a few photos from my last few flights this weekend and last.

  • #2
    A few reference photos of the full sized machine that I’ve found as handy references for detailing.

    Comment


    • #3
      Looks awesome, F106.

      Comment


      • #4
        Originally posted by PawPaw View Post
        Looks awesome, F106.
        Thanks! Finally finished up the blade paint today. Should look pretty neat in flight with the high-vis scheme.

        Click image for larger version

Name:	7EFB5DA6-BE8F-4BA6-B850-2232AF9E885F.jpeg
Views:	948
Size:	172.0 KB
ID:	280667

        Comment


        • #5
          Regarding the rolling takeoff/tail clearance mention: I discovered those wire tail skids are very brittle, either by design or just cheap metal. My B407’s snapped flush with the fin base but the impact appeared to be very slight. No damage at all to the fin. Instead of replacing the skid with tougher metal, I opted to reuse the fractured skid & installed a brass coupling to hopefully preserve the fin from my future ignorance. Click image for larger version

Name:	FA9A9E72-D286-4AD5-86C0-B7D1FF2B1977.jpeg
Views:	605
Size:	141.0 KB
ID:	280715Click image for larger version

Name:	1097D043-DAA1-43A2-BF1E-11F09532B663.jpeg
Views:	632
Size:	123.4 KB
ID:	280716

          Comment


          • #6
            Very nice, I'll keep that in mind. Still need to paint up my stinger as well. Got the cockpit and pilots installed today and got in a few flights. Love how those high-vis blades look in flight!

            Comment


            • #7
              A few closer shots of the new pilots

              Comment


              • #8
                Very nice! That’s some awesome photography also.

                Comment


                • #9
                  Got in a few flights with Chris Pry’s Airwolf this afternoon. Was great to see both 222s in the air together!

                  Comment


                  • #10
                    Got in a few flights on Friday doing running takeoffs and landings on pavement with the 222. Handled it well for a while, but at the end of the day one of the gear up-stops let go. Was able to set it down in the grass gear up with no damage luckily. Upon further inspection, the other gear stop was fatiguing as well. It was only a matter of time before it would fail as well. Will be reworking these in aluminum soon. In the mean time, here’s a few flying photos from that day:

                    Comment


                    • #11
                      Awesome, F106!

                      Comment


                      • #12
                        Finally got around to fixing my main gear down stops. Removed the stock wooden stops and fabricated new ones out of 1/8” aluminum and bonded them in with hysol. Also added a searchlight under the rear fuselage. I used a landing light from the Freewing F-14 and connected it up the a digital switch so I could turn it on/off from my TX. The main issue was, that I’m running 7.5V, and the LED is only designed for 5V. To resolve this, I soldered an older Freewing BEC in line with the servo power wires to step down to 5V. Not the cleanest setup, but it seems to work well.

                        Comment


                        • #13
                          A few photos from this evening doing some night flying with the Roban 800 Bell 222. The searchlight worked great!

                          Comment


                          • #14
                            Mitey Nice!

                            Comment


                            • #15
                              I’m currently building the same choppa, I did quite a few changes to mine, not so true to scale changes just a few personal fantasy mods. I replaced the head entirely with a 4 blade head, also installed a unilight light system. I may need some assistance since im not the shabbiest when it comes to setting up electronics. I had a friend helping me at first but I would like to learn the systems to make it more user friendly for me in the long run.

                              Comment


                              • #16
                                I am building a Roban 800 Bell 222. The front retract mount was not included. Any help on where I could buy one would be highly appreciated. No luck with Roban

                                Comment


                                • #17
                                  Originally posted by LeonBotha View Post
                                  I am building a Roban 800 Bell 222. The front retract mount was not included. Any help on where I could buy one would be highly appreciated. No luck with Roban
                                  Retract mount? The piece of plywood that the retract unit mounts to is missing? Hard to imagine how that could have been missed in assembly. Can you show a photo of what you need? I have some parts leftover from the wreckage of my 222.

                                  Comment


                                  • #18
                                    Thanx for the response. Yes, I could not believe that it was not installed. The rear retract mount is included for installation but as far as I can see the front plywood mount should have been installed. I will send you picks later today.

                                    Comment


                                    • #19
                                      Click image for larger version

Name:	FD5C9734-34A7-4A37-9A32-829A3C22EFCF.jpeg
Views:	107
Size:	45.0 KB
ID:	352842
                                      Attached Files

                                      Comment


                                      • #20
                                        That is exceedingly bizarre. Unfortunately, I don't have any of the plywood left for the front retract mounting area. I have the retract unit itself, and the main gear mounting plate. Have you contacted customer service? To me this is a clear factory error and should be covered. You'll probably have to scratch build a retract box otherwise.

                                        Comment

                                        Working...
                                        X