Feb 10, 2013, 12:23 PM
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sniper1's Avatar
Thanks again for the pics mate! But let me get this straight- You drilled a hole in the black plastic tub to insert the metal trunnions to go all the way through and into the fuse to get a flush fit?
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Feb 10, 2013, 04:36 PM
B-58 Hussler

Elevator Trunnions - each independent shafts

Sniper1, If I understand your question, NO each side is independent. I did not go through the fuselage to the other side. I did not take pictures of the trunnion assemblities as I made them! Darn me! Let me try to explain.

First the plastic trunnion. If you look at the Trunnion housing there is a closed end and a open end. The open end allows you to place the steel collar and long lever screw, as in the picture you refferenced above. Looking down there are three open cells perpindicular to the elevator shaft. This gives to four walls total, two inter and two outer walls. These outer two are the walls you will drill for the bearings to be incerted. The two inter walls make the center cell that holds the steel collar with the shaft passing through it. The collar secures the elevator shaft fro falling out.

I drilled out both outside walls to the outside diamiter of the bearing. These have to be centered with the actual shaft hole center. Because I used a 4mm carbon shaft as my elevator piviot shaft (see my earlier photos). I had to drill out the two remaining inter walls to 4mm, currently they are the size of the steel L-rod that Fly-Fly uses. (Note: the bearings must be a little wider than the cell so that the outside wall holds the bearings in place. (two bearings per Trunnion)

After the Bearings are in place and new sized collar is in position - slide the assembly together and cut the carbon shaft to size. I left 10 mm to slide into the fuselage foam - it does not interfer with the exhuast flow. You will have to drill a little into the foam to fit the trunnions and full elevator assembly flush with the plane's fuselage. Then fit your lever screw down on to the carbon shaft to set after all placements are where you want them. after you are completely sure making sure that your bearing surfaces are flus with the walls pour a little 5 minute epoxy in to the two outer cells now occupied by the bearings to secure them into place. I say a little at a time because you want the bearing cell completely filled when you are done, but not so the freeze the bearings.
Feb 11, 2013, 01:16 PM
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sniper1's Avatar
Thanks for all the effort you put into helping me out with that detailed description and photos! You answered my question and more, despite slightly misunderstanding my predicament. I just wished I had drilled through the outer wall of the elevator support housing and into the fuse before I glued the thing in there. I'm not an experience builder, so when I saw a hole in one side and not in the other, I presume it is not supposed to have a hole there, especially when nothing is mentioned in the instructions.

These forums, and the patient people in them, have saved the day again!
Thanks for all your help!
Feb 12, 2013, 12:56 PM
Registered User
MADISONMaster's Avatar

F100 FLYFLY : MODS - Construction of elevator and the new location for servo


another method....

Feb 13, 2013, 02:59 PM
B-58 Hussler

Leading edge slats Mod???? Anyone comment?

I have a general question for anyone that has done the leading edge stats modification. I am thinking of doing it to my F-100.

Did you notice any difference? Did it improve the handling ? Now that you have modified the Hun, would you do anything different? Still if you didn't fly your f-100 before without (?), i would still like to hear from you-all!
Feb 13, 2013, 04:47 PM
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4stripes's Avatar
Originally Posted by Hussler View Post
I have a general question for anyone that has done the leading edge stats modification. I am thinking of doing it to my F-100.

Did you notice any difference? Did it improve the handling ? Now that you have modified the Hun, would you do anything different? Still if you didn't fly your f-100 before without (?), i would still like to hear from you-all!
I cut the leading edge and hinged it at the top. Added trailing edge flaps (split flaps as I didn't want to weaken the wing in that area. Both are connected to one servo in each wing and they drop together. Works great, and the plane has no bad stalling habit (stalls straight ahead). I also added the belly airbrake which works well. Neither the flaps or airbrake change the trim when deployed.
My flying stab is stock except I added a CF strip along each trailing edge. The best mod was using a Changesun 12 blade 90mm fan. I'm pushing 2300watts and the plane flies great! I wouldn't do anything different if I had to do it again.
Feb 13, 2013, 09:47 PM
B-58 Hussler

12 Blade CS - Questions

Thanks for resopnding Big-E, What motor did you settle on? What kind of thrust do you think you are getting? Please explain you Huns flying habbits a bit - if you don't mind. I have noticed that several folks describe what they are doing, and less about what it has done for the flight characteristics. I am a fair builder, but I am timid flyer! (read not so hot!) Ilike to build way beyond my flying ability! Ha!
Feb 14, 2013, 05:30 AM
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4stripes's Avatar
The turnigy XK 4074-B-1400 running 7S is holding up well with cooling holes drilled in each end, along with external cooling fins. Thrust in the plane is about 3.5kg. I added the LE flaps after my good experience doing the same with my Starmax F/A 18. It worked well on my Starmax F16 (after beefing up it's linkages and hinges). What they do is help with take off and landings. More lift making lift off easier. Yes, there is also more drag which really helps give a stable approach with power on (just like full size jets). Stable approach speed gives more consistent landings. Stall speed is reduced as well with no top stall tendencies. Some will say they are not needed on a foamy but they do help in my opinion.
Feb 14, 2013, 05:45 AM
Registered User
Probably like flaps are always useful on any plane (foamie opr not). So a bit more of a 'tool' for landing (or any slow flight situation) can't hurt.

How did the front cap come off the 4074? I have never taken off a front cap as they seem "well held on"... loctite? The rears usually pop off easily enough.
Or did you drill the front one in situ, with the armature out of course!
I need to do a few of my fully closed inrunners. (a XK4074-1400kv also)

With the bearings.... "all of a sudden" (and it is seemingly weird) I have three motors (3674-1650kv, 3674-1660kv, and the X-Flight outrunner) that feel 'graunchy' to me. If run up on their own they have some 'resonations' - which I figured are the bearings. So I took out the armature and spun it off just the one end breaing (for each end) and they feel
'graunchy'. But if you can assure it is dead centred and no offset weight on the bearing - eg spin it with the armature/shaft vertical - it is not graunchy. So it seems they can rotate cleanly unless there is any offset pressure - which I expect ALL motors will have some! Due to imbalances etc.
So I tried a few 28mm motors and they seem to do similar. And now it is making me wonder if ALL motors do that anyway! I had never noted it before!
I would assume GOOD bearing would be dead smooth in all manners.... so I suspect they really are 'pitted' or something... all of those! The 3674-1650kv and X-Flight outrunner were brand new though....
Feb 14, 2013, 11:37 AM
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4stripes's Avatar
The motor shaft end cap has 4 Allen screws to remove and the cap will come off. The other end has 3 small screws that must be carefully removed (they strip easily, so I loosen them first with pliers). That end may have a little glue holding it as well but you can force it out from the inside.
As for bearings, most of these HK motors have cheap noisy bearings but I haven't bothered to replace them (yet).
Feb 14, 2013, 03:23 PM
Registered User

how to loosen (heavily loctited etc.) screws...

Originally Posted by 4stripes View Post
The motor shaft end cap has 4 Allen screws to remove and the cap will come off. The other end has 3 small screws that must be carefully removed (they strip easily, so I loosen them first with pliers)..
I once tried to dismantle a (Lander) inrunner - the small Allen screw heads were not providing enough grip for the torque needed, so I quickly ruined them.
To weaken the effect of loctite you can heat up a screw, but that's not always possible without harming other parts. Another method I know is to hit a screw hard, but that is also out of the question here. How do you use pliers to save the screw head (or the thread, I don't quite know what you talk about when you say that they "strip") - thank you for the time and help
Feb 14, 2013, 04:22 PM
Registered User
4stripes's Avatar
A pair of pliers with nice sharp little teeth can grab the outside of the 3 small Allen screws and they can be loosened with the pliers. Once loose, the Allen key can be used to unscrew them completely. If you look at the plier handles close to the hinge, they have a small section with teeth as well for more gripping power.
Feb 14, 2013, 04:35 PM
Registered User
thanks - now I know what you mean. I encountered flat head / counter sunk screws on outrunners, and there is no way you can get at them with pliers
Feb 14, 2013, 04:41 PM
Registered User
4stripes means on motors with an allen head screw/bolt... seeing that sticks out of the motor case. No use for the philips (cross head) silver screws that are countersunk into the motor case.

"Strip the thread" means the thread of the screw (usually) or the nut/tapped-thread is mangled and can't hold the other items thread solidly anymore.
But I think he/you meant 'mangling' the screw cross head - the screwdriver part of the screw. I don't think it has a technical term really.... you just 'mangled' the screw head! LOL
err.... damaged.... ruined.... gouged..... hehe

Firstly you want to use the correct screw driver to perfectly suit a screw always, if you can. Buy some.... if they aren't suited to all (or this) task... buy some more others.... Align (helicopters) make high quality and accurate screws driver and allen driver sets! And they will cover 80%+ of all situations you encounter with motor/EDF model stuff. But also have a good quality jeweller's screwdriver set.
Secondly, as you feel force build up YOU have to be the limiter to stop damage before it occurs. You can actually 'feel that coming'.
You also need a combination of very good inwards force, to assure the screwdriver tip has its best chance of remaining seated in the screw head at all times. One slip and it can all be over with these cheap Chinese screws!!
Feb 14, 2013, 06:27 PM
Registered User
4stripes's Avatar
Quite right Peter,
I meant mangle not strip.
Those cheap allen screws only give you one shot sometimes. The pliers worked better than any of my metric or english allen keys on those small screws the XK4074 has.

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