RunRyder RC
 1 page 673 views POST REPLY
HomeAircraftHelicopterKyosho Caliber/Quest Neo-Caliber series › nexus clutch shoe bolt help
08-16-2010 04:21 AM  8 years agoPost 1

rrKey Veteran

Central Pennsylvania

My Posts: All  Forum  Topic

I have a nexus 30. About a month ago, when I landed and dropped the collective to idle, the rotor kept spinning fast. Shut it down and the the clutch drum was siezed to the motor. Got it home and when pulling apart, found the 3x6mm cap screw which holds the clutch shoe to the cooling fan had snapped. Had a little trouble, but got the screw piece out of the threads. Could see a little bevel to the sides of the screw hole in the fan but not any real damage to the threads. Got a new screw and put it back together. This past saturday when flying, the same thing happended again. Pulled it apart and found it was the same screw that snapped. This time, I couldn't get the old screw pieces out and had to go to a spare fan I had. When I was at the field, I had gunned the throttle a few times from idle as I am changing fuels and was testing engine response. I am wondering if this quick throttle action caused torque on the bolt and snapped it.

Is this a common problem for the nexus and how is it fixed? Whan putting locktite on the bolt threads and whan it breaks in the hole, there is just about no way to get it out. Too small for easyout and a drill bit walks and caused thread damage. I am tired of dealing with this problem. Thanks.

BTW, the fan that got stripped, I drilled and tapped the hole for 5mm, put a 5mm plug in it with JB weld, filed it smooth and am working on drilling out the plug and re-tapping for 3mm. Not sure if it will hold or not, but the plug is very hard metal and having trouble getting a hole thru it. I had another spare fan, but the back that goes up against the thrust washer was about 1/3" longer than the fan I took off, not sure why. I cut it down to match, but by the time I got it flat (cut at slight angle), it was not too short. Think it will be ok to place another washer between the thrust washer and fan to take up space? Would hate to knock the bearing out of the motor.

08-20-2010 09:50 PM  7 years agoPost 2


Mexico city

My Posts: All  Forum  Topic

Make bigger holes on the fan using a 1/8 drill bit. Pay attention here, the hole should be a little smaller than 4mm. Then retap to 4mm.
You must also bore out the clutch shoes to 4mm. (7/32 bit)
Mount the threaded portion of the bolt (4mm) on a drill, then by using a (8193) grinding stone, mounted on a mototool, grind off the bolt´s head so it fits in the clutch shoe.
That will allow using 4mm bolts insted of 3mm on the clutch shoes. A lot stronger than 3mm and won´t brake away indeed.

Happy flying!!

PM  EMAIL  Attn:RR  Quote
 1 page 673 views POST REPLY
HomeAircraftHelicopterKyosho Caliber/Quest Neo-Caliber series › nexus clutch shoe bolt help
 Print TOPIC  Make Suggestion 

 1  Topic Subscribe

Friday, August 17 - 2:04 pm - Copyright © 2000-2018 RunRyder   EMAILEnable Cookies

Login Here
 New Subscriptions 
 Buddies Online