B E L T D R I V E T A I L R O T O R A D A P T E R DAWSO S Ridgecrest, California 93555 www.approachengineering.com
1.0 Purpose To establish a process that ensures control and standardization in the manufacturing of the Tail Rotor Belt Drive Adapter. AP104. 2.0 Tools Required Note: (A) denotes tools required for assembly and (T) denotes tools required for testing. Basic Hand Tools (A, T) Allen Wrenches Small Socket Set (A) (A) 3.0 Reference Documents Exploded view drawings AP104. (A, T) 4.0 Attachments 5.0 Introduction 1. WAR I G This aircraft is not a toy. It is capable of serious bodily harm and property damage. Every precaution must be taken to properly build this kit and install all radio components. It is your responsibility alone to ensure all safety steps are taken outlined in the Academy of Model Aeronautics safety codes. If this is your first time building a aircraft kit it is highly recommended that you find experienced help for the first flights. Consult your local hobby shop or write to the AMA for further guidance. Academy of Model Aeronautics 5151E. Memorial Drive Muncie, IN 47302 (800) 435-9262 2. Please inspect all parts before building. If any parts are broken or missing please feel free to call or write for replacement. If you have any questions, comments, or improvements please call or write to: Approach Engineering www.approachengineering.com 3. We as the kit manufacturer can provide you with assistance and a top quality kit and instruction manual. When built light, straight, and true you will have a model that flies as well as it looks on the ground. However the finished product depends on the quality built into it. We can not guarantee the flight performance. Take your time and read all instructions carefully before and during construction. BELT DRIVE ADAPTER PAGE # 2
6.0 FUSELAGE ASSEMBLY 6.1 Using the second longer stepped shaft place the other bevel gear with the gear face facing away from the stepped shaft. Align the hole in the shaft with the hole in the gear body. Press in the 1/8 shaft to hold in place. Press in the 1/8 shaft to hold in place. 6.2 Press in the four 1/4 ID x 1/2 OD flanged bearings into the bearing blocks. Install them such that the flange fits flush in the recessed portion of the bearing block. The flanged face will fit flush with the bearing block. Front Side Flush Flanged Side Back Side 6.3 Press in the four 1/4 ID x 1/2 OD flanged bearings into the bearing blocks. Install them such that the flange fits flush in the recessed portion of the bearing block. The flanged face will fit flush with the bearing block. 6.4 Remove the belt drive gear and shaft from your tail rotor gearbox. Install it on top of the assembly and align the hole in the shaft with the pulley. Install the shaft and lock in place with a 2-56 set screw. Flanged Surface Washer 6.5 Using the shorter stepped 1/4 shaft place one bevel gear over the end with the gear face facing towards the stepped portion. Align the hole in the shaft with the hole in the gear body. Press in the 1/8 shaft to hold in place. Pin 6.6 Place one washer over the short end of the shaft protruding from the gear face. Slide the aluminum spacer tube on the other end of the shaft. Spacer Washer BELT DRIVE ADAPTER PAGE # 3
6.0 FUSELAGE ASSEMBLY 6.7 Install the other two bearing blocks so that the flanged bearing surface are facing toward each other. 6.8 Lay out the shaft assemblies on the on top of one frame side. Pull out two of the tail rotor shaft support brackets and lay them in place. Flanged bearing surface 6.9 Place the other two tail rotor shaft support brackets on top of the first two. Place the one with the hole on the lower location with the hole closer to the bearing block. 6.10 Place the other side frame on top of the assembly. Pull out the 4-40 screws and nylon lock nuts. Install the screws and lock nuts but do not tighten the screws surrounding the tail rotor shaft support brackets. Bracket Hole 6.11 Slide the new belt into the assembly by first wrapping it around the pulley. Then push it through the tail rotor shaft support bracket until the belt wraps around the pulley. 6.12 Using the short tail boom shaft with the machined slot in the end, slide it into the mechanics. Once fully inserted tighten down the frame tail boom screws. BELT DRIVE ADAPTER PAGE # 4
6.0 FUSELAGE ASSEMBLY 6.7 Install the adapter by sliding the belt through the short tail boom section and around the mechanics drive pulley. Pull the adapter section until proper belt tension is achieved and then lock down the tail boom support brackets. (Tail boom Sections are cut from your tail boom, 2 1/2 & 3 pcs.) 6.8 Pull out the other tail boom shaft and the two shaft housing support rings. Place a small amount of epoxy around the outside surface of the support rings. Slide the first one in one inch inside and the other flush with the same end. (Support Rings come with Apache 50) 6.9 Trial fit your mechanics into the fuselage and cut the driveshaft housing about 3/4 from the back face of the adapter. (Housing, Adapter and Flex Drive come with the Apache 50) 6.10 Using a dremmel tool cut your original flex shaft down to the appropriate length. For extra security you can also put some JB Weld on the end of the flex shaft. Using removable loctite tighten the set screw so that it comes in contact with the flat on the shaft. (Drill 2 holes to tighten Set Screws) 3/4 6.11 Slide the tail boom shaft over the flex shaft housing with the flush support ring facing aft. Install the mechanics by threading the flex shaft through the housing. Then slide back the support tube into the tail rotor adapter. 6.12 Once satisfied with the fit tighten down the screws locking down the tail boom short shaft. BELT DRIVE ADAPTER PAGE # 5
7.0 Testing and Maintenance 7.0 Ensure free movement and no binding of the adapter assembly. 7.1 Check all proper belt tensions. After the first flight recheck the belt tension. Verify that all screws remain tight. 7.2 Ensure that you have proper engagement of the flexible shaft with the telescoping tube tail rotor. 7.3 Ensure that the tail rotor blade plane is perpendicular to the aircraft center line. 7.4 Continue to check gear wear and flexible drive shaft condition annually. 7.5 Thank you for your interest in Approach Engineering aircraft. We are committed to provide any necessary help to make your project a success. We would love to see pictures of your completed aircraft and add it to our data base on the website for others to enjoy. BELT DRIVE ADAPTER PAGE # 6
8.0 Raptor Tail Rotor Gearbox Adapter 8.0 You may convert your Raptor tail rotor gearbox from a belt drive to a shaft drive by combining some Century components with your current gearbox. The additional parts needed to complete the conversion are: 1. Gearbox housings PN: HI3078 2. Ball Bearing tail pitch horn PN: CNBB0360F 3. Spacer Tube PN: HW3074 4. Tail Gearbox Input PN: HW3070A 5. 5x13x4mm Bearings PN: CNBB 1350 6. Control Horn PN: HI3102B 7. Tail Gear Set PN: HI3075 8.1 Disassemble your current gearbox as shown. You will be left with just the main shaft and tail rotor blade assembly. 8.2 Install the two bearings into the gear box housings. 8.3 Slide the tail rotor shaft into the housing with the servo bellcrank mount. Slide on the gear spacer and smaller bevel gear. Pin the gear to the shaft and secure with the set screw. Spacer Set Screw Smaller Gear Pin 8.4 Prepare the input drive shaft by first pinning the larger bevel gear and secure the pin with the set screw. Slide the two bearings onto the shaft. Insert the assembly into the opposite half of the housing and set proper bearing spacing by securing the flex drive adapter with a set screw and loctite. 8.5 Assemble the two gear box halves together and check proper gear mesh. BELT DRIVE ADAPTER PAGE # 7
8.0 Raptor Tail Rotor Gearbox Adapter 8.6 Assemble the bellcrank by installing the two flanged bearings into each side with the brass spacer between the two bearings. 8.7 Place the brass washer between the lower bellcrank bearing and the housing arm. Bearings Spacer Washer 8.8 Secure the bellcrank with the socket head cap screw. 8.9 Install the completed tail rotor to your completed aircraft. Connect and check travel of the tail rotor pitch horn. 8.10 Thank you for your interest in Approach Engineering aircraft. We are committed to provide any necessary help to make your project a success. We would love to see pictures of your completed aircraft and add it to our data base on the website for others to enjoy. Please remember that Dawson s Approach Engineering can not except any responsibility for your usage of this product or instructions. You are solely responsible for your actions with this or any other Dawson s approach engineering product. How you build or what you build is up to you. Happy Flying! BELT DRIVE ADAPTER PAGE # 8