John_M_

What, no air mattress and mini frig... obviously you haven't pissed the wife off to the point of being sent to the "Dog House" for the night , nice dog house though... you need to put a VERY large bowl of food & water out by the front of the door... that would keep the unwanted away!



John M,

spaceworm

For what it is worth:
"Correct Procedures for Rigging a SuperCub
Per Piper Service Bulletin 910A, Service Memo No. 19, the procedure for rigging a
PA-18 and PA-19 is as follows:

Rigging Procedure: Raise the forward part of the airplane so that the wheels are just
clear of the ground, and support it by props under the front landing gear fittings. Raise
the tail to approximate level flight position and support it there.
Leveling:
Level the airplane as follows: Drop plumb bob from P. K. Screw in door
frame top channel to intersect punch mark in enclosure door rear hinge.
Dihedral Angle:
To check Dihedral angle at the front spar, proceed as follows:
Stretch a string along the top of the wings above the front spar, from wing tip to wing tip,
and draw it tight.
Check the dimension vertically from the string to top of fuselage front spar wing hinge
fitting. For correct dihedral this dimension should be 3 1/8 inches.
To check for equal Dihedral in each wing, proceed as follows:
Using the 30 inch level (without any spacer blocks), hold it spanwise against the bottom
of the wing under the front spar in the space between the jury struts and lift strut
attachments. Note the position of the bubble and do the same on the other wing. Readjust
the front struts until both wings show the same amount off level, being careful with
each adjustment to set the left strut out the same number of turns as the right one is set in,
and vice versa.
Wash out:
To adjust the wash out in the wings (dihedral of the rear spar), proceed as
follows:
Set a 3/8 inch spacer block on top of the 30 inch level at one end. Working on the rib
adjacent to the outer end of the aileron, hold the level fore and aft along the bottom of the
rib with the spacer block at the rear and the front end of the location of the front spar.
The correct wash out will exist when the bubble is centered. Adjust the rear struts in or
out to obtain this condition.
Tail Assembly
: With the airplane in level position, the stabilizers should be leveled at
their rear spars. The hinge line should be straight from tip to tip.
Plumb the fin at the rudder hinges."

The distance, at 1/4 scale for the space from the string between the wing tips "to top of fuselage front spar wing hinge
fitting should be 3 1/8" inches divided by 4, or 0.781 inches.

Over and out. Sincerely, Richard

acerc

Thanks for posting that Spaceworm. At .78 inches on our 1/4 scale models there is very little visible dinedral. And it is even less visible with a clipped wing. I would assume most kit and ARF mfg's give more dihedral for better recovery of the aircraft. This is a safety net for themselves by means of a better experience from the end user. Most end users prefer a better flying experience over a true scale model.

Leroy Gardner

Yep I remember those service memos Richard and vaguely the string, took 3 guys to set it up and get one wing right, at any rate the close to 11/16" per side dihedral for 1/4 scale may be good for some, I believe the 1.5 deg. per wing will improve handling of our scale models. As far as wash out goes from what I know this plane will fly fine without it however I have seen builds where builders do put some in it, for what gain I don't know as I have never had to deal with it.

I have always believed you could build a perfectly scale plane and have worked on a couple EAA models for wind tunnel tests that were but someone was going to be flying in it not controlling it from the ground. Yes I know all about Top Gun planes and pilots and they are far from the average RC fliers. Tweak it and make it more friendly to the thumbs, might last longer too.

Leroy

VincentJ

A little late, but I just wanted to add my two cents on TNT products and service. I have used them on more than one occasion and have had good service and reasonable delivery of their products to my door...

John_M_

Leroy, I just checked my dihedral using the method described by spacewalker rigging method, and mine measures at 1", scale would be 3/4" or 13/16"... that image I posted of that Piper L-18C, looks like its more than 3 1/8", but images can be deceiving... go with what you feel is right for your build.




John M,

rt3232

My Feedback: (6)

Hay Leroy

As I have not even done more than hang the plans on the wall, So as you build does this kit build in the washout ? or do you put it in with the struts.

Cheers Bob T

Leroy Gardner

Vince it's good to see you here, your never too late. As far as TNT is concerned the delay I had last year was the result of their supplier, not anything they were doing. I have spoke to Kathy and Tom both and find them to be sincere about the whole business and service comes first, Like so many others in this industry they rely on suppliers and they wait for stock also.

Leroy

Leroy Gardner

There is no wash out on mine, may not need it and at the same time the rear strut could be used to put some in it if it's adjustable.

Leroy

John_M_

Regarding the washout... I've flown with, and without washout on the same cub... there is an appreciable / noticeable difference in flight performance, but nothing that makes it mandatory, or a must have.

"Without washout", she had a tendency to float on approaches, needed power applied and down trim... she fell out of turns at slower airspeeds, but manageable... and of course the nasty snap / stalls on takeoff, but that's usually pilot error when that happens, I've never really experienced it, but have come close a few times, that's were you need plenty of reserve power ... she was totally predictable, unless you really stall it close to the ground, then recovery is almost impossible, but that's pretty much a given with most RC aircraft.

"With washout", the turns were easier to coordinate, less tendency to balloon when power was applied abruptly... on approaches she would always come up short on final (sinks) and needed some power applied along with some up trim, but just enough to keep her on the glide-slope (just took some practice)... rolls were ok... inverted flight was ok in level flight, but fell all the way out in turns.

If you want a more sporty flight characteristic where you can do some aerobatics, then "no" washout... if you want more of a scale flight characteristics, then put washout... I had it setup with -1.5 degrees... -1 degree may improve the sink rate on approaches and the inverted flight characteristics.




John M,

acerc

Mine has no wash-out either. Shims at the mount would do the trick if wanted or needed. I don't know how but after completion mine had some wash-out and a shim (basically a washer) took care of it, and being between the strut mount bracket and the wing it can't even be seen, .

John_M_

Being a clipped wing cub, washout wouldn't do it Justus Ace, would be defeating the whole Idea of the CW... my inlaw flies his H9 cub with washout, he says its feels better on takeoff... I think as long as you keep the airspeed up you don't need it.



John M,

Hinckley Bill

My Feedback: (569)

Leroy.....I want your shop, or at least something close to that size!

Kind of funny, with the kids married and out on their own we're thinking of downsizing the house but I want a shop that's way, way bigger....a 20' x 40' (or 60') pole barn would suit me just fine

Keep up the great build...I'm subscribed and in it for the long haul with ya'

Bill

FlyerInOKC

My Feedback: (6)

And attached to the wall a very large broken section of logging chain!

Corsair2013

My Feedback: (2)

+1 Hinckley - small house - LARGE Workshop.............. that way the wife won't ask you to help clean and you have a place to stay when it gets "warm" inside........

K

tedbmoss

I am not an A&E, but I helped rebuild 22 Piper Cubs when I was 16 years old, just the airframes. It was a lot of sanding and priming and sewing Irish Linen and doping; about 6 coats; nitrate,anti fungal, butyrate,aluminum power mix and yellow . They all had dihedral. The washout was to keep the wing tips from stalling first. I am rebuilding an old Hanger 9 SuperCub that an expert pilot dumped into the ground on landing when the wing stalled. I checked the washout and it was actually washin on the wing side that dropped off. (Warped). I put some washout in the wing and some dihedral.

Leroy Gardner

Some of this wing setup does more to cause confusion and if you add the prop wash from the bigger engine along with the torque roll tendencies on the real plane you can figure this is no trainer as a model, it's a flat bottom wing that you have to fly just like the real one. I have spoke to pilots that have put 150 & 160 HP engines where there was once a 135HP and the air frame did not like it especially the 160 with that 78" prop. I here this model likes a 16" prop and a 18" prop will cause the same thing it does on a real one, lots of rudder use. While the model can be aerobatic to a degree the real one was not. I think I'm going to find out more about flying from the ground with this one.

Hey, where the dog house is concerned, my lovely wife has never put me in it but has came out there a few times to get me out of it, how sweet is that. I don't go out there to eat or watch TV, my back door is only 12" from the shop one, "very convenient " to say the least and no there is no bed either, have one in the house

I gotta get to work,

Leroy

Leroy Gardner

John-M you post a lot of good Information offering choices on setup, I just hope I do it right the first time, won't have to pick up the pieces, " yikes ", don't want to think of that.

Robert I like your approach, don't worry about it, I hate those " what If's " that linger in the back of the mind.

Now I'll get to work.

Leroy

acerc

Here is some excerps from manuals provided to me by Cubman in regards to dihedral.
"From a page out of the L-4 maintenance book. talking full scale, stretch a string from tip to tip along the front spar. in center should have a 4 3/8 gap from top of center wing section to the string.

From a J3 book, it has 4.25"

And this is the last I will speak of it here.

cubcrasher

My Feedback: (6)

Wash in, wash out, washey clothesy. That big fat wing can handel anything you can throw at it. Don't know
if either of mine have wash in or out. I eyeballed the dihedral and they both fly good. And another thing. If
you watch me fly them it will make you want one.

John_M_

No need to reply on this Ace, just an observation.

It's interesting, spaceworm shows it as 3 1/8" in his post (#127) for the super cub.... but none the less, if its 4.125" for the J3, then I'm golden at 1"



Just make is so it flaps it wings Leroy, that way you'll have all the bases covered,




John M,

acerc

All I meant was I'm done hashing over it. It has been covered quite well and I believe the consensus is "whatever one likes". I have seen them with minimal (such as mine at zero) and so much they look like a Tower trainer. Never heard anyone have a bad experience either way.
Be careful what you advise, I have seen one with flapping wings before.

John_M_

LoL, I've seen some wings flap as well... but the funny thing Ace, no matter how hard they flap, they never make it back to the runway.


https://www.youtube.com/watch?v=iMhdksPFhCM



John M,

Leroy Gardner

Some of that stuff is funny but what can happen is not. Personally I think if you stick to the plan where all these things have been tested for flying before the plans and manual were even written you will be okey.

Now I have accomplished a little on the build, all the spreaders are in and they will get the gusset treatment, rear cabin former is in (after the picture) and gear mount is in, I recessed it in the bottom sides (not on the plan) and made a new one to replace the kit one. I will use the gear supports to mount the floor as was intended. Tomorrow it's on to the fire wall and chin, I'm hoping the wing tube shows up by Saturday so I can get the wing center made up and on then I can do the turtle deck. It's going pretty good considering the Tightbond waiting, you know how that goes.

Here's what I have for pictures.

Leroy

cubcrasher

My Feedback: (6)

Nice work.