RE: Sig 1/4scale C/W Cub build
 

Ok,

Thankyou very much to all of you. Very good advise and very quick response.
I am so grateful.
Cheers,
Sidekick.

RE: Sig 1/4scale C/W Cub build
 

Robert,
Quick question, Scrounging in my shop I found a 22" piece of thin wall AL tubing I was going to use on another wing. Any reason it wouldn't work fine for a clipped wing cub?
At 25% of span it's probably a bit overkill but should make it nice and strong.

Thanks,
TM

RE: Sig 1/4scale C/W Cub build
 

No reason what so ever. But you will need a tube for it to go into. I can tell you how to make a tube. If you want  PM me.

RE: Sig 1/4scale C/W Cub build
 

My turn! I'm making a little progress. At this rate I figure I'll be done in less than two years! (Hopefully a lot less.)

First of all, I want to say hope everyone had a very good Thanksgiving! http://www.rcuniverse.com/forum/js/f...unge_smile.gif Now to start working off the calories! http://www.rcuniverse.com/forum/js/f.../cry_smile.gif

I finished up my Plug-n-Play wing. I fabricated a little cover to hide the wires in the back of the cabin area. I also left a hatch to access the wing center section... just in case.

I also am finishing up my control sticks. I got the floor, sticks and control tube painted. Need to let it dry a bit longer before re-assembling. I'm also adding a micro servo under the front seat to work the stick sideways movement. I intend to use a Y connector in one of the aileron channels to control it. Since the elevator servo is in the fuse, I'll rig up a mechanical connection directly to the servo arm... some how.

Here are a few photos:

RE: Sig 1/4scale C/W Cub build
 

Hmmm. Very well you have done.

RE: Sig 1/4scale C/W Cub build
 

I've nearly finshed the right wing. Still a few things to do like finish shaping the leading edge and wingtip, adding the little piece of sheeting on the wingtip and adding the servo hatch. Starting the left wing now.

Pic 1: right wing
Pic 2: starting the left wing

RE: Sig 1/4scale C/W Cub build
 

Looking good Neddy!

RE: Sig 1/4scale C/W Cub build
 

Happy turkey day to all! Hope everyone had a good weekend off.
After finishing up another plane and spending the day with family, I got my table cleaned off and unpacked the kit to label the parts. Holy Crow that's a lot of sticks! [:-]
I made copies of the plans at work last week so I cut those up for the top and side views then started on the formers.

I started using Elmer's wood glue but has anyone built one of these using CA only for the regular joints? Obviously epoxy is needed here and there but I mean regular butt joints and such.

Also, Robert I did shoot you that PM in case you get a chance to check your inbox.

RE: Sig 1/4scale C/W Cub build
 

I useCA for most balsa to balsa joints. But I use wood glue for everything else including balsa to balsa stress points.
I had to take a look and I did send you a responce to your PM.

RE: Sig 1/4scale C/W Cub build
 

Got it, thanks.
I work from home so I have been stealing moments here and there; after my workout and before work, then at lunch and I'll work a bit more after I "punch out".
The formers are together and I'm working on the fuse sides. With any luck I'll have enough pins to also get the horizontal stab glued up tonight.
Last night I made a whole bunch of dust cutting the marked parts out of the balsa sheets.

I think I'll continue using the Titebond on the fuse joints as it fills gaps better. But I will likely use CA on the wing's tighter joints.

RE: Sig 1/4scale C/W Cub build
 

The left wing is coming along. Since I am modifying it to plug into the one-piece fuse center section I am building it like the right wing instead of per plans (left wing-center section as one piece). This post is to show in detail how I built the dihedral brace box within the wing. The plans for the right wing call for it to be built in-place in the wing. That didn't make sense to me so I built it outside the wing and then installed it.

Pic 1: I made a jig from scrap 1/4" ply that lines up with the bottom of the dihedral brace slot on the root rib, for the brace to sit on to hold it to the proper dihedral. I'm putting 1 degree of dihedral in the wings so I cut the jig to 91 degrees (not 89 like I wrote on the jig)
Pic 2: A pic of the dihedral brace through the slots on the jig.
Pic 3: Since the left wing isn't supposed to be built this way per plans I had to cut new pieces of 1/8" ply for the box sides (pieces P4 per plans)
Pic 4: I dry fit the ply box backing with the dihedral brace in place and traced the top of the brace onto the ply to mark the angle and where the 1/4" spruce box top should go
Pic 5: 1/4" spruce scrap glued to the top of the ply piece at the mark I made for the correct 1' dihedral angle
Pic 6: bottom 1/4" spruce stick being glued into place. I used the brace to make sure the fit was tight and removed it as the glue was drying so it didn't get accidentally glued in.
Pic 7: ply piece with sticks glued into place

RE: Sig 1/4scale C/W Cub build
 

Pic 8: back of the box dry fit with the brace in place. Fits very well.
Pic 9: front piece of ply glued on to complete the box
Pic 10: Per the plans the box is glued only to the balsa ribs and sits just a little forward of the spars. I used some scrap spruce and sanded it down to fit snugly between the box and the spars then glued it into place. I did this to add more strength/support to the box for when I'm taking the wings on/off before I have the functional struts in place to take the weght of the wings.
Pic 11: Edges of the box glued to the ribs. Dihedral support brace complete. This was exactly what I did when I built the one in the right wing.

RE: Sig 1/4scale C/W Cub build
 

Nice Neddy.  Interesting building techniques.  I built my per the plans (particularly since I had very little building experience) and it held up very well.  There was (and is) no worry of damage before getting the struts on.  But hey, better safe than sorry I guess.  Next time though, I'll build the center section into the fuse and use the tube method for wing mounting.  So much cleaner!

Oh yeah, nice detailed explanation on you build too!  I like it!

Keep 'em comin'!
David

RE: Sig 1/4scale C/W Cub build
 

Here's some shots of mine. The wing panels are retained with thumb screws through the front and rear spars to fitting mounted to the cabin structure, ( I can get some better shots if anyones interested ).
The centre section is now just a cover that clips on when the when you've finished rigging the wings. After purchasing what was a very unloved and damaged J3,this method was the easiest and most practical way for me to fix what had been turned into a one piece wing with a dubious centre section repair.

RE: Sig 1/4scale C/W Cub build
 

Nice Job Neddy, it's coming along!

David, Your cub is all "tricked out"... looks great. Now FINI**** !!!!!!!! LOL

RE: Sig 1/4scale C/W Cub build
 

Hey, when you don't got no money, you gotta make it last!  ;)

RE: Sig 1/4scale C/W Cub build
 

Neddy, Thanks for the great photo break down. It is nice to see very clear pictures and have a good description to go with them.
So far I have just framed up the fuse and horizontal stab so there's nothing interesting to report. It's all per plan and surprisingly the build is moving along faster than I expected. :D

I'm sure the purists will scream for my blood, but I'll be building the wing as a 2 piece, tube supported affair with zero dihedral. Not so much for any performance gains it just will build faster and easier. None of my other planes use dihedral so why trouble with it here?

I contacted Fiberglass Specialties and they were very nice to email me pictures of the J3 cowl with engines and without since they don't have the pictures posted on their site. Would anyone like to see them or are you guys all well past needing a cowl?

RE: Sig 1/4scale C/W Cub build
 

I'm past the cowl bit myself.  I bought the one with the engine and now wish I had gone without and did the built up dummy engine.  They look so good!

Take care,
David

RE: Sig 1/4scale C/W Cub build
 

My build is slow. I'm almost 3 months in and haven't finished the wings yet.

RE: Sig 1/4scale C/W Cub build
 

Man! I'm three month's in on my Pitts and I haven't even opened the box of wood yet.

RE: Sig 1/4scale C/W Cub build
 

Which Pitts you building? German kit? I'd love to build a S2

RE: Sig 1/4scale C/W Cub build
 

Hey there Neddy! Welcome to my world! http://www.rcuniverse.com/forum/js/f.../msn/49_49.gif

Robert, you darn well know why you're so stinking slow. Because you built two others in that time! SHEESH! http://www.rcuniverse.com/forum/js/f...sn/biggrin.gif

RE: Sig 1/4scale C/W Cub build
 

Not a kit. It's a Andy Sheber plan build. The box of wood is what I ordered from BUSA for it.

RE: Sig 1/4scale C/W Cub build
 

I'm still planning to build the S1-11b one day but I've always loved the old school Pitts.

RE: Sig 1/4scale C/W Cub build
 

Well, I know your one step closer to that Lil Stinker.
By the way, if you wanna start a s1s sooner I have some plans for that too. ?
Better yet I know where one can get a real, real, real nice kit.