essyou35

My Feedback: (11)

Interesting note on the trim.  With the way my stabs are, the front is lower, so I would expect it to climb out and need down trim.   I guess the best thing to do is hit the throttle and get it up there fast so I can trim it out if needed.

Ok next weekend I will fly!  Assuming its not 30 mph winds again of course.    I plan to have an onboard video.

jetflyr

Just got back from Austin, TX and the Central Texas event. And yes she flew and flew (7 flights the first two days, flights 41-47)
First: I don't work for Henry, and if he patted me on my shoulder I wouldn't know who he was.
Second: I am primarily a scratch builder, and an inveterate kit basher... I know the way *I* like to do things......
Third: The first one I built was built as a review airplane for Model Aviation, so it needed to be built 100% according to the plans (it's a review, not a kit-bash article!)

That being said......I have built two, and had my hands in two others. Both of mine had the stabs AS DRILLED, with the wings set flush with the bottoms. With my CG approximately 1/8-inch behind the recommended CG (personal preference) I fly 1 click of "up" elevator up here at 7000 feet, and 3 clicks of down at near sea-level.
With 43mm of flaps, she slows down very nicely, BUT it can take time if you deploy at too high of a throttle setting, or wait until short final to drop them.......JUST LIKE EVERY OTHER AIRPLANE.

With the recommended crow set up (though I only have 43mm of flap) I need three clicks of throttle all the way to touch down. If you get her too slow on short final, she will raise her nose and you will become a Kangaroo. When slow, the crow setting (with the tanks) REALLY stabilizes mine, the only thing mine doesn't like is a hard cross wind (and some of that could be my mind set)

All that being said, I have to agree with Henry's comment: "Agian I can't tell you what to do with your money but I do not reccomened changing any stab settings"
I do know I've seen the wheel reinvented with some of the posts here, and since I have actually flown two of them, I'd de-rate the control throws (too fast for scale) and that is about it.
Build it as written in the instructions, go fly and THEN modify to taste. Henry has done a REALLY GOOD job bringing a model to teh market that works as advertised. If you want to complicate things (I frequently do [&:] ) that is your prerogative, but PLEASE don't claim omniscience!

Greg

jetflyr

NEVER!
It will swell the O-Rings and make them unusable. Use Parker "O-Ring Lube", which is available through McMaster-Carr, Fastenol, BVM and probably Dreamworks.

Greg

essyou35

My Feedback: (11)

Opps, I just got done putting vasoline on them.  Where can I get new seals?  It also did not seem to help at all, one tire is very stiff, the other did losen up.  I need new ones anyways.

Ideas?

jetflyr

Contact Henry, or Bill at Spring Air.....
Greg

essyou35

My Feedback: (11)

OH yeah.  Hoping its something I can get at ace hardware. 

 BTW 30 mph winds kept me from flying, going to aim for next weekend.  I did run it up, pipe didnt collapse, thats good!

mtnflyer14

I also had one wheel that was very stiff. I swapped the tire/rims from one strut to the other and it helped quite a bit. Obviously, the rims and axles were not milled to exactly the same size.
Regards,
Gus

brelaw

Yes essyou I will wait as it will take me several months to complete anyway due to work I don't get as much time on it as I would like. I do think you are right now about the stab holes, I will most likely leave them alone, Henry also says same thing. Thx for the help
Brett

essyou35

My Feedback: (11)

I did a lot of work on my brakes. I did use vasoline on them but that had no effect on them and nothing changed. I ended up having to sand one of the orings down a bit as it was way too tight. It came to me like this. I used my dremel to turn the tires for a few minutes to wear the o ring, now when I spin my tires I get 1 full turn before they stop without brakes.

With brakes, I can still push the model around on the ground, its hard to push but it does push, is this normal? I am not sure how strong the brakes are supposed to be. Applying 100 PSI and confirmed they are getting all of that.

mtnflyer14

SU35; did you swap the tires/rims from one strut to the other? That helped a lot on mine. The issue isn't the axle rubbing, it is the inside diameter of the rim that the o ring expands against. Give it a try. Regarding the brakes, with full brakes applied, my tires lock up.
Regards,
Gus

essyou35

My Feedback: (11)

yes, i swapped, the issue is with the hub, not the tires.

kimhey

Yes

essyou35

My Feedback: (11)

thx kim.  ill try a taxi test, see how well it stops.

essyou35

My Feedback: (11)

Well been waiting a couple weeks to fly this, and I still continue to tweak it.  It weights 21lbs 8oz all wet.  Today there is a 17mph wind, angled to the runway, we might go fly it.  Seeing how its been 40mph gusting the past 2 weeks it seems calm today.  The guy I am flyiing with flies in a lot of wind all the time.

Well let me list my worries or regrets now so if one gets me we'll know I knew about it.

elevator not symetrically mounted, so I expect some roll on take off.  (one has different AOA than the other)
I also may expect some elevator trim needed if the holes are not right.
The fuel tanks may bust open, someone shot them with a machine gun.
the pipe will collapse, I know it is not perfectly aligned but I cant get it perfect, when it looks straight one way it looks cricked another.  Even the CF rod I was using was slightly cricked.    All my formers are cricked so no real point of reference.
Finally, my  brakes may cause me to yaw off the runway.  I got them loosened up to be about the same resistance but they are awful.  I plan to send them back to Springair and get new ones.  With them loosened up to the same resistance, they dont provide a lot of stopping power.

I dont think there is much I can do to fix any of the above, it just will have to be trial by fire.  I did run the dog up a bunch and no issues with the pipe.  I plan to fly off at 5000 ft runway so if I dont have brakes it will be ok.

I do wonder though for some of the people having elevator trim issues, if it has something to do with thrust angle?  There are several degrees the pipe can move both up and down and back and forth.  I do know a coupe degrees can cause trim issues as I have a jet with thrust vectoring on it.  Just a thought.

I bolted my pipe dead center left and right, and to the bottom of the fuse.  Lets hope my thrust angle is good.

Ok let me say it for you:
"Greg:  Quit being a little beep and go fly already, it flies fine as is".

Ok Greg, WISH ME LUCK.

kimhey

Good luck

essyou35

My Feedback: (11)

Thanks Kim, wind picked up to mid 20s so may have to wait again.  Grrr. 

jetflyr

/>Ok Greg, WISH ME LUCK.



[/quote]

Good Luck!
Greg

essyou35

My Feedback: (11)

Another question!  I did a taxi test yesterday, the winds were strong, say 20-30 mph.  I only put a little fuel into it, but on the ground I could not control it.

It kept weather veining into the wind.  When I would get it to steer into the cross wind, the front tire would start skidding when I turned and the jet would turn back into the wind.

A lot of time when I would turn, the jet would just start bouncing on the front tire like it was skipping, and not actually turn...

My CG is no more than 30 CM back form leading edge, probably closer to 28-29. 

I've never had this issue with a jet, all my bigger EDF shrug the wind right off.

I know one rear tires has more resistance than the other, but didnt think it was that much.

Does this sound tail heavy or is this to be expected in high winds?

I'll recheck CG and try again in lower winds.  BTW brakes worked well, I was shocked that at idle thrust the jet gets moving fast.

jetflyr

My CG is right at the front of the rear spar, so check that, but, yes the nose can get very light in that strong of a cross wind.

Greg

mtnflyer14

SU35,
I've never tried to taxi mine in a 30 mph crosswind, but I'm guessing it would react exactly like yours did. I think you need to put your F-86 away until the wind stops blowing, or move out of Nebraska!
Regards,
Gus

essyou35

My Feedback: (11)

Thanks guys.  Yes, I need to move out of Nebraska.     Hey I've waited 2 weeks to do this, the winds havent let up at all.  Now my guy issnt available for 2 weeks so we'll see if I decide to go out and let her go anyways.

I am shocked the nose gets that light, the wing loading with no fuel must be along the lines of a slow stick, which btw I flew in that same wind while I was out there.

Ok no strong cross winds for the dog.  Noted.

BTW, I needed 3 batteries (2200mah), 6 oz of sticky led, and seven .45 caliber bullets to get the dog balanced.  The bullets are CA's to the mounting board all my stuff is mounted on, I was shocked how strong they hold! 

Lead wise that is about 9.5 oz, the bullets also have copper in them.  Lipos not sure. 

jetbro

Hi all , just joined up..
I recieved my Sabre D 3 days ago and have studyed it and this thread well..
so glad i know where to look twice now
mine survived shipping with no damage , still waiting on the KT-80 .. bought the landing gear combo also..
i measured the horizonal stab ,wing incidence using the engine mount as level reference and have 1.6+ with the wings matched well to the fuse bottom... so happy about that
only have front former at nose gear block slightly missaligned but gear well centered and strait.. I seem to have a strait kit

also , i discover a trex 500 tailboom will make a lovely main wing tube sleave..

the wheel well covers are unusable as they will not allow full gear retraction..

I will work to avoid the tail heavy build from the begining..hav a few ideas

for gear , will use all hyperion swervos , DX-8/AR9100 , electrodynamics #125 gear/brake manager , 3x LiFe 2100 , BVM smoothstop2 , BVM UAT , rhobert valves ..

Also,will bottom hinge the flaps for enough degree throw for the Kingtech..

This is my first turbine , so fingers crossed , lol

mtnflyer14

Good luck with your new F-86! I have two 6.6v LiFe 2100 Mah packs in the 'pocket' on the left side of the fuselage and a 9.9v LiFe in the nose next to the air bottle and only needed 4 ounces of lead in the right pocket for good CG.
Regards,
Gus

essyou35

My Feedback: (11)

Did you ever wiegh yours? I am wondering, short of getting al lighter turbine, if any weight savings can be had. If you do save weight somewhere, you end up adding more in the nose!

mtnflyer14

No, I don't know how much the airplane weighs. I have the Kingtech K-80 installed, did not glass the wings, have the Springair retracts/struts and didn't do any other significant modifications other than the brass tube and fibreglass tube to guid the main spar and aluminum spars respectively. We are at 6500' MSL here and the airplane certainly doesn't need any more thrust than the K-80! Greg thinks his fiberglassed wing/contol surface version is a little heavier than the stock version like mine, and he likes the extra weight, but I don't think he knows exactly how much extra that added.
Regards,
Gus