bikerbc

Does your dowl run full length across the elevators ? Mine Was just a short piece about 4" long that joined the two together.. After it was epoxyed together I glassed it for extra insurance.. That also covered the hard points for servo horns . It added practically no weight...I used 3/4 oz cloth...I used maybe 4 square inches .. Not even ..

Props4ever

Yes, I'm running dowel full length covering both elevators. I suppose shorter one would work also but I didn't changed the original design, just
made newer section following original design except for adding trusses to give more strength and preventing surface from twisting....
I will also be adding hard points for flying wires/struts on both stab n the fin.

Props4ever

Other thing that I'll will do is to tie the key joints like dowel LE to TE with carbon toes, ill wrap it around, so this way, there is no way those joints
will ever fail for the life of this model.

smkrcflyer

So I’m considering building a ¼ scale clip wing cub because its really the plane I would like to have. I built the Sig ¼ full wing version years ago but did not like the way the wing is attached. I would like to keep the center section on the fuse and have two wing panels. Has anyone done this? I think the BUSA cub is like that but its not clip wing. Could I reduce the wing size to 83 inch?
For power I want a 4 stroke twin is the 160 enough power or too much?

SunDevilPilot

I've modified the center section on a Sig 1/4 Cub like you are describing. Here is a link and a photo of the modification.

(In the photo I just installed the top glass so some of the glue is still visible)

http://www.rcuniverse.com/forum/m_88..._1/key_/tm.htm

SunDevilPilot

Cub Flyer Fresno

I like the way you did that, SDP.  Simple!  Just don't forget to hook up your struts!  [X(]

SunDevilPilot

The Struts are 100% functional. If you loose them the wings will fold immediately. However, with the struts the wings are rock solid, just like the full scale!

SunDevilPilot

rafeeki

My Feedback: (11)

Pl. listen to the voice of experience... If and when the strut mounting point at the wing fails your wing will FOLD. Use a wing tube...

Rafeek

SunDevilPilot

A wing tube may help but it is not needed.....

If my strut attachments rip out of the wing, which fully capture both main spars, then a wing tube wouldnt save the plane.

The struts themselves are aluminum with brass pins and JB Weld holding them together. I doubt I could rip the stuts apart.

SunDevilPilot

rafeeki

My Feedback: (11)

That is nice workmanship
My wing struts were hinges at the point of attachement tp the wing so I could fold them for easy transportation. The hinge pin failed so you get my drift....

smkrcflyer

SunDevilPilot
Your struts are very nice. I built ones like that for my cub. How are you attaching them to the wing?

SunDevilPilot

4-40 bolts into blindnuts.

My struts are fixed on the wings leaving them as strong as possible.

You can just see the bolts in this photo.

I'll also post my cradle, how I transport the wings to the field.

SunDevilPilot

smkrcflyer

Vary cool. That's a big prop what engine do you have on it.

SunDevilPilot

The prop is a 20X10 on a Hacker A60-7S motor (Electric).

stevegauth30

Hey sun devil, real sweet looking cub you've got there. I'm a big fan of your struts. Makes me want to re do mine. Awesome job.

Props4ever

Stabilizer and elevators are all structurally complete, here are 3 shots of present stage.

Making hinge blocks from hardwood, installing them, drilling holes for the hinges and adding Robart point hinges is next followed by making hard points for the wire/cable struts.

Elevator control horn will be the last thing to be added before covering is commenced.

stevegauth30

Lookin good. Can't wait to see finished/restored cub.

Props4ever

Thanks Steve, it's coming along nicely.

Starting on fuselage soon.

Props4ever

Dry mounted the stabilizer on the fuselage, fuse was brought in the hanger, placed on the table and then lift from bottom of the rear fuse till cabin windows are level. I figure Cub's water lines goes right under the cabin windows.

I use old boxes to prop up the fuse and then placed new stabilizer at its location, it was tilting a bit to right. As it turns out that aft most section of longeron isn't perfectly level which forced old stab to til on right side.

I used Popsicle stick and 1/16" piece of balsa sheet to use as shim, this lifted up the stab, making it perfectly level and square to the fuselage.

Water level was placed on top of the stab's center base to make sure stab is perfectly level.

Props4ever

Stripped fuselage.

Lets see if someone can figure out who's kit built or scratch built this Cub is now the most of the covering is stripped off from the fuselage.

It has double pull pull system, one for rudder and other for elevator!, funny thing is, instead of both cables from servo going to the flight control surface directly, they stop in side the fuse aft section, connected to servo arm and then there are 440 rods the go through the right side of fuselage to operate flight control surface it's for ie: Elevator or Rudder.....

As I stated before, internal main structure of the fuselage is in very good condition, it needs some cleaning to make it pretty looking again.

stevegauth30

Is it just the arm, used kind of like a bell crank? Seems like unnessasary weight. Are you going to run the cables all the way or keep it like it is?

Props4ever

Yes it sure is access weight and I really don't see any logic behind using it instead of routing flight controls from one side of the fuselage. Plus there is a tail wheel servo and 2 440 rods on it also which again I don't know why it was used.
Tail wheel could easily be hooked up with 2 springs from either side of the rudder as it's on actual aircrafts and would have been fine....

I'm not sure as yet how I will go about it, prolly in coming days I will figure out what I want to do on this end. But for sure lighter tail is much much batter the heavy one!

rafeeki

My Feedback: (11)

Will the stabilizer end up being perpendicular to the firewall?

In other words what I am looking for is the relation between wing, stabilizer and firewall if any one knows. I dont.

Rafeek

Props4ever

Spent last 4 hours cleaning all the longeron, stringers, trusses by light sanding them after all the covering was pealed off. This model has all sorts of covering!, films, fabric, tissue, paint you name it, iI was surprised how many layers I had to take off from the forward fuselage section!. I counted 3 layers of covering at minimum that came off.

Took the front windshield off the fuselage, it took 45 mins to do it very carefully with out damaging it, so in the end all is good. Turned around and found some black power stuff, sorta like black plant sand all around the edges of the windshield and the frames and above the dash board, not sure what this stuff was but it was oil based!. How long it's been on the model I have no clue or where it came from.

It took another hour to sand off black stuff off front top of forward fuselage, section behind the firewall but in front of the wind shield. I used 100 grit paper with block to sand as much off ass possible. You will see cleaned picture of this section.

All the frames were also cleaned with rag, this area has some tissue covering the wood with paint on it, so maybe tonight I will try to sand off old paint as much as I can.

I'm going to post pictures of the fuel tank compartment, this area also have this black stuff on the back of firewall, on its top of compartment ans the floor. Also looks as couple of different engines were also mounted on this model in its carrier, you can see filled holes from prior engine mounts and present holes for G45 that was on this model. I'm going to fill all holes, sand front of the firewall flat, then add 1/8" plywood sheet to give it face lift as well as add reinforcement at the same time.
Once I figure what this black crap is, I'll sand it off and then spray K-Tone spray to see if this stuff gets pulled from back of this compartment, hope fully it will come off as this stuff did dried up firewalls and compartments soaked with glow fuel on few other model in the past.

Then plan is to reinforce pretty much all of this compartment with carbon fiber and epoxy resin.

Props4ever

Lets see if you guys can see something different now...