Fej f-18 stabs
10-21-2013, 02:44 PM
#1
Thread Starter
My Feedback: (18)
Join Date: May 2004
Location: houston, TX
Posts: 328
Likes: 0
Received 0 Likes
on
0 Posts
Fej f-18 stabs
Hi
Went to load up my 1/6 scale fej f-18 this weekend to take to a jet rally for its 14th flight, did a small check over and found play in the right stab.
The shaft had play inside the elevator. Cut some 2" x 3" access panels on the bottom of the stab, one forward of the shaft and one aft of the shaft.
I could then see the counter rotating screws that were installed into honeycomb. Thats were the play was, u could take a hobby knife and stick threw the HC with very little effort just 1/8'' away or next to the counter screws.
Guys please inspect your airframe carefully before every flight, Especially if your a FEJ Honeycomb Aircraft owner.
Thanks
Robert Bernal
Went to load up my 1/6 scale fej f-18 this weekend to take to a jet rally for its 14th flight, did a small check over and found play in the right stab.
The shaft had play inside the elevator. Cut some 2" x 3" access panels on the bottom of the stab, one forward of the shaft and one aft of the shaft.
I could then see the counter rotating screws that were installed into honeycomb. Thats were the play was, u could take a hobby knife and stick threw the HC with very little effort just 1/8'' away or next to the counter screws.
Guys please inspect your airframe carefully before every flight, Especially if your a FEJ Honeycomb Aircraft owner.
Thanks
Robert Bernal
10-21-2013, 03:07 PM
#2
Senior Member
Join Date: Jan 2003
Posts: 1,172
Likes: 0
Received 0 Likes
on
0 Posts
Especially if you play outside the nature of things..
Here we go again...
Say you had one ballanced static and one without.
Which of them would be "in your mind" as time goes by?
But I totally agree, no such ancor should have a base in just HC.
A tad of mircoballoons under tough ply is all it takes to get the grip. But should be a mandatory thing, no matter manufacturer.
Both...
Here we go again...
Say you had one ballanced static and one without.
Which of them would be "in your mind" as time goes by?
But I totally agree, no such ancor should have a base in just HC.
A tad of mircoballoons under tough ply is all it takes to get the grip. But should be a mandatory thing, no matter manufacturer.
Both...
Last edited by Falcon 64; 10-21-2013 at 03:14 PM.
10-21-2013, 03:28 PM
#3
Thread Starter
My Feedback: (18)
Join Date: May 2004
Location: houston, TX
Posts: 328
Likes: 0
Received 0 Likes
on
0 Posts
Both stabs were static balanced by the builder before the plane was ever flown.
The play was very small, don't now why the right stab got the play first, but it was just a matter of time after what I seen inside the stabs.
Thank
Robert Bernal
The play was very small, don't now why the right stab got the play first, but it was just a matter of time after what I seen inside the stabs.
Thank
Robert Bernal
Especially if you play outside the nature of things..
Here we go again...
Say you had one ballanced static and one without.
Which of them would be "in your mind" as time goes by?
But I totally agree, no such ancor should have a base in just HC.
A tad of mircoballoons under tough ply is all it takes to get the grip. But should be a mandatory thing, no matter manufacturer.
Both...
Here we go again...
Say you had one ballanced static and one without.
Which of them would be "in your mind" as time goes by?
But I totally agree, no such ancor should have a base in just HC.
A tad of mircoballoons under tough ply is all it takes to get the grip. But should be a mandatory thing, no matter manufacturer.
Both...
10-21-2013, 03:51 PM
#4
Senior Member
Join Date: Jan 2003
Posts: 1,172
Likes: 0
Received 0 Likes
on
0 Posts
Then be glad you got 13 flights...and checking.
This means the shaft is placed too far forward, too much force on the servo, but of course, the ancor in HC is a nono..
Shaft too far back is also a option, but would be interesting to see a good picture of it. My dimes in too far forward.
Optimum would be "no" stress on the servo and torque in the shaft, as long as it`s "shaft-driven".
Thats when the symphony gets together and plays as one unit.
I will upgrade elevators on both my Skymaster and FEJ F-16 to "Avonds style".
This also makes it easy to remove the elevators, for transporting the model, done in seconds.
This means the shaft is placed too far forward, too much force on the servo, but of course, the ancor in HC is a nono..
Shaft too far back is also a option, but would be interesting to see a good picture of it. My dimes in too far forward.
Optimum would be "no" stress on the servo and torque in the shaft, as long as it`s "shaft-driven".
Thats when the symphony gets together and plays as one unit.
I will upgrade elevators on both my Skymaster and FEJ F-16 to "Avonds style".
This also makes it easy to remove the elevators, for transporting the model, done in seconds.
Last edited by Falcon 64; 10-21-2013 at 04:06 PM.
10-21-2013, 09:04 PM
#6
10-21-2013, 11:06 PM
#7
Back when people actually knew how to build they would static balance the stabs, instead now its throw a 20kg servo on it and jimmy up a linkage that is all the wrong geometry...
10-22-2013, 01:29 AM
#8
Robert glad to heir you picked up on this on the inspection of your aircraft. At least know you can fix the problem and have more enjoyable flights. Yes I guess it should not happen but it is what it is so at least you picked up on it. Just goes to show inspections are a must on all brand aircrafts.
On the other issue on balancing stabs and this is just my logic opinion. I believe that it would be better to balance the stab so the load on the servo is reduced. Look at it like this. Pick up a length of steel at one end and see how hard it is than if you pick it up in the middle when it's balanced. I believe the only reason why everyone that doesn't balance the stab gets away with it is because of the over power servo people choose to install.
On the other issue on balancing stabs and this is just my logic opinion. I believe that it would be better to balance the stab so the load on the servo is reduced. Look at it like this. Pick up a length of steel at one end and see how hard it is than if you pick it up in the middle when it's balanced. I believe the only reason why everyone that doesn't balance the stab gets away with it is because of the over power servo people choose to install.
10-22-2013, 01:53 AM
#9
Senior Member
Join Date: Jan 2003
Posts: 1,172
Likes: 0
Received 0 Likes
on
0 Posts
Would been interesting to see a picture or two. I sounds like you have the locking-pins vertical on the shaft, when those are glued the HC..
You can tell if the other elevator is different by scanning it in a airport-scurity scanner. Since it behaves better I mean..
You can tell if the other elevator is different by scanning it in a airport-scurity scanner. Since it behaves better I mean..
10-22-2013, 02:00 AM
#10
Robert has already repaired both stabs using the same method that EDFJim used on his smaller F-18 stabs.
http://www.rcuniverse.com/forum/rc-j...ild-fej-6.html
http://www.rcuniverse.com/forum/rc-j...ild-fej-6.html
Just was courious on the counter rotation screws that was locking into HC..
10-22-2013, 02:38 PM
#13
Hi
Went to load up my 1/6 scale fej f-18 this weekend to take to a jet rally for its 14th flight, did a small check over and found play in the right stab.
The shaft had play inside the elevator. Cut some 2" x 3" access panels on the bottom of the stab, one forward of the shaft and one aft of the shaft.
I could then see the counter rotating screws that were installed into honeycomb. Thats were the play was, u could take a hobby knife and stick threw the HC with very little effort just 1/8'' away or next to the counter screws.
Guys please inspect your airframe carefully before every flight, Especially if your a FEJ Honeycomb Aircraft owner.
Thanks
Robert Bernal
Went to load up my 1/6 scale fej f-18 this weekend to take to a jet rally for its 14th flight, did a small check over and found play in the right stab.
The shaft had play inside the elevator. Cut some 2" x 3" access panels on the bottom of the stab, one forward of the shaft and one aft of the shaft.
I could then see the counter rotating screws that were installed into honeycomb. Thats were the play was, u could take a hobby knife and stick threw the HC with very little effort just 1/8'' away or next to the counter screws.
Guys please inspect your airframe carefully before every flight, Especially if your a FEJ Honeycomb Aircraft owner.
Thanks
Robert Bernal
1. Leave it on the ground and appreciate how pretty it is.
2. Throw it way.
Good. Now, never buy another one.
10-23-2013, 08:15 AM
#16
For me this is the bigger problem. They don't seem to fail in the normal window people use to determine if a jet is "good". After 15 to 20 flights you start to trust your jet and wring it out some more, take it to events and generally have a good feeling that structurally and mechanically it is sound. Lewis' A7 had approximately 60 to 70 flights (if I'm not mistaken) which is generally way more than most people would need to trust their jets, then without warning a structural failure that was there since that second hole was drilled in China months ago. It is this insidious nature of the problem that I think will bite someone.....
10-23-2013, 08:59 AM
#18
For me this is the bigger problem. They don't seem to fail in the normal window people use to determine if a jet is "good". After 15 to 20 flights you start to trust your jet and wring it out some more, take it to events and generally have a good feeling that structurally and mechanically it is sound. Lewis' A7 had approximately 60 to 70 flights (if I'm not mistaken) which is generally way more than most people would need to trust their jets, then without warning a structural failure that was there since that second hole was drilled in China months ago. It is this insidious nature of the problem that I think will bite someone.....
10-23-2013, 09:08 AM
#19
My Feedback: (76)
Join Date: Aug 2004
Location: Baton Rouge, LA
Posts: 2,715
Likes: 0
Received 0 Likes
on
0 Posts
Hi
Went to load up my 1/6 scale fej f-18 this weekend to take to a jet rally for its 14th flight, did a small check over and found play in the right stab.
The shaft had play inside the elevator. Cut some 2" x 3" access panels on the bottom of the stab, one forward of the shaft and one aft of the shaft.
I could then see the counter rotating screws that were installed into honeycomb. Thats were the play was, u could take a hobby knife and stick threw the HC with very little effort just 1/8'' away or next to the counter screws.
Guys please inspect your airframe carefully before every flight, Especially if your a FEJ Honeycomb Aircraft owner.
Thanks
Robert Bernal
Went to load up my 1/6 scale fej f-18 this weekend to take to a jet rally for its 14th flight, did a small check over and found play in the right stab.
The shaft had play inside the elevator. Cut some 2" x 3" access panels on the bottom of the stab, one forward of the shaft and one aft of the shaft.
I could then see the counter rotating screws that were installed into honeycomb. Thats were the play was, u could take a hobby knife and stick threw the HC with very little effort just 1/8'' away or next to the counter screws.
Guys please inspect your airframe carefully before every flight, Especially if your a FEJ Honeycomb Aircraft owner.
Thanks
Robert Bernal
Bob, please post your fixes, I have the same jet and its been grounded until I get valid fixes, I have emailed FEJ regarding updated stabs but they haven't responded, I'll replcate what you are doing on mine to make sure they don't wiggle out.
Thanks,
10-25-2013, 08:48 PM
#21
Senior Member
Join Date: Jan 2003
Posts: 1,172
Likes: 0
Received 0 Likes
on
0 Posts
My F-16 is the best I have ever seen.
