TDR-Manual 2009 - Henseleit Helicopters

Chapter – IV T a i l b o o m ( Assembly Group 8 )The bearings 0813b with the fixedbushing are pressed into the plasticbearing support 0813a.The two bearings 0828b and 0828c are pressed into the bearing flange 0828a so that they are flush with the flange. Thebearing 0828c additionally has to be tigthened using a small amount of Loctite (only degrease the outer bearing areacarefully). The pinion 0824 and the clutch 0831 are secured using two locking pins 0832.You need a round rod with a diameter of about 20mm and a length of about 1m to press the bearings supports 0813 into thetail boom.Use a thick felt-tip pen to mark three points at a distance of 220 mm, 410 mm, and 610 mm respectively starting at the endof the rod. Now take one of the bearing supports and press it into the CFK boom 0800 from behind (the side with the crossholewith a distance of 12mm from the boom edge) into the tail boom 0800, such that the side of the plastic bearing supportwith the larger hole diameter (i. e. the side from which the bearing has been pressed in) points to the back.You will notice that the bearing supports deform the boom to a certain extent. So, they keep their later position when beingunder tension.Use the rod to press the first bearing support into the boom until it reaches the 610 mm mark which is aligned to the end ofthe boom. Press the other bearing supports into the boom in the same way. The middle bearing support is inserted up to the410 mm mark and the last support is pressed in until it reaches the 220 mm mark.In order to exchange the bearing supports after a crash, press them out of the boom from the front. In most of these casesthe CFK boom is broken or torn. So it may be necessary to saw it into three pieces to remove the supports (Attention ! Riskof injury).The drive shaft 0810 is pressed through the bearings from the front side. Do not use excessive forces to press the shaftthrough the bearings. In the normal case it can easily be pushed through.If you do not find the hole of the second and third bearing immediately, slightly bend the shaft until it slides into the bearingand can be pressed further.Attention! It is recommmended to cover the clutch 0831with a shrinking tube. So, the driving pin of the driveshaft 0810 does not move out, if it becomes loose.The pinion shaft bearing flange is now pushed into thetail boom and tightened using the two M3x6 screws0828d.The drive shaft 0810 is not yet inserted in the clutch0831 !At first, it is moved through the boom until it points outat the back.The boom will be assembled to the mechanics and the struts later. The assembly of the push rod will also be described later(chapter X).14