Hi all, wondered if anyone has jr 8411s on elevators on sm f15. These servos are giving me 5mm total slop on elevator leading edge, is this acceptable? Also useing dubro heavy duty plastic servo arms and clevis, i think these will be strong enough, is this ok?

Regards Steve

Steve...I have 8611s on my elevators. They are working fine and have been for over 70 flights. I also have the dubro arms on mine and they too have been fine, no probs. I did however swap out the pushrods from SM and replaced them with the H9 titanium rods. I put a dubro c/f locking clevis on one end and a ball link on the other. Mine is an older F15 and the clevises that came with it were kind of fragile looking.

Mike

I have JR8511s fitted with heavy duty clevises and tight fit on both horns, yet there is still some slop due to the size of these elevators. I also added some lead to the elevator leading edges for balance. Total about 60 flights flying with elevon setup.

B777

Steve,
Slight slop is normal when using 8411's due to the gear lash inherent with this servo. 5mm seems a bit much. Can you take a picture of your linkage setup, would help us to see if it can be improved any?... Is there any play in the linkage or is the slop strictly from the servo itself?

Todd,
I have a similar problem with my setup. However, I am using 8611. I have a lot of slop in the elevator too. Havent measured how much. I am using tight ball links and most of the slop is from the servo itself. Whatever comes from the linkage is probably from using the dubro HD arm..seems like we may have to use metal arms.

Hi Ragz,

!!!Off topic question!!!
Where do your guys fly jets at New Delhi?

B Regards

I'm using 8611's, metal arms, and titanium links and I have a couple of mm of play in the elevons. I have traced it directly to the servo. There is absolutely zero slop with this linkage set up.

I've found slop in the metal arms, we started using heavy duty plastic arms here in TX. I can't guarantee it, but in many cases I've seen with my own eyes the servo blamed for the little bit of slop to actually prove that in fact it's not the servo and something else. I always tell someone to go back and re-look at it 5 times if they have to, there is almost always something more you can do to remove slop if it's there. That being said, on the eurofighter, that was the worst airplane to try to get slop out of because of the flex in herent in it's hinging system.

Steve,

Stop worrying and fly the thing or I will bit*h slap you.

St Athans here me, steve and the F15 come.(plus a few of my models if I can fit them in the van the f15 takes up some space)

All the best

Ant

Steve, we suggest 8511 (8611 in us).

AsiaSRC, I dont fly jets in delhi. Although there are a couple of large areas that will handle turbine jet flight. Sohna is one such place. I actually fly my jets in Nagpur (central India) this is where I live. We sometimes go down to Hyderababd and fly off a full scale strip or go to Pune and fly at a strip there.