rt3232

My Feedback: (6)

acerc/Robert

When I built my sig cub that would be about 2000 and I was not even aware of RCU at that time I even went back to look at old film neg's to see if I had saved them after putting it all on that h/d, should have just put them on a cd which is ware every thing I have sence joining RCU. When I got my first T/F G/S Corsair and looked/opened that box that is ware I decided I need some help and got on the old group build.

That's enough B/S back to Leroy's build thread.

Cheers Bob T
AMA13377 Corsair Brotherhood # 6

flyoz

My Feedback: (7)

I love build threads I get to build vicariously between my own builds and always learn new tips

re the tank. I used a Thundertiger X50 Heli Tank PV1328 (8cmWX9cmLx6.5cmh) 14oz (430cc) squarish shape that tucks away out of site well (they may also have a bigger ones for the 60 and 90 size helis PV0310 Lg 550cc 18.9ozFuel Tank and
MA128-100 15.5 oz. Fuel Tank Set).[h=1][/h]).

i hide wires by running up behind the center cabin struts and across the rear cross member covered with cardboard bent as half tubes painted as interior and tack glued to wires with some silastic. The D connector idea is great Acerc.

PS to make the wing struts easier to mount for regular flying I extended an aluminium tongue off each point of the strut that attaches to the Fuselarge that was long enough to fit under the fuselarge. I then drilled 1/4 holes up thru the alumin plates and the strengthened floor to accept 1/4" DSUS pins which just 91/4 turn) twist lock into their base plates in a fuselarge mount block.
you can glue on balsa or plastic bits to the alumin to resemble the real turnbuckles. (i leave the struts attached to the wing. the triangle spe isnt to much of an issue when loading in the car escpecialy when the wing halfs are turned inwardes 180deg to each other).

spaceworm

I have the kit built Sig 1/4 scale J3 and the generation 1 Hangar 9 100 inch J3, and neither one has any dihedral (that I can see) in the wing. How/where did you arive at the "1.5 deg. per side"? Thanks, I am very curious.

Sincerely, Richard

acerc

I would like to know as well for I thought it was a half a degree.
After some thought I believe the cub wings are flat and any dihedral was added with the struts. Of which varies widely by the owners preference of flight characteristic's.

John_M_

I think the full size cub has a bit more dihedral than one would expect... here's an image of a Piper L-18C ( based on the Piper PA-18-115 Super Cub )... its the only image I could find quickly that really shows the dihedral well.

http://www.airliners.net/photo/Skywo...-18/1937318/L/






John M,

rt3232

My Feedback: (6)

Guys I went to the same web site spent all most a hour looking at those birds and you can see from flat to my estimate of about 1.5 deg's, so with my little knowledge of aerodynamics dihedral makes for an easer flying plane, by that I mean when properly trimmed it will fly straight and level and will not tend to roll left or right, a flat wing like an monocop, that I was a partner in one back in the early 60's you had to be on the stick at all times but fun to fly.
So take your pick

Cheers Bob T

Leroy Gardner

Robert I did see the truck light idea, I gotta stop just thinking planes. I have a very dense drilling board and I cut a relief in it when drilling with a forstner bit, there are two kinds of them, a bottom hole bit and a through hole bit, the through hole bit has perimeter cutters that cut before the clean out cutters make contact and there is no tear out but the bottom of hole will spin on the bit, just raise it and take it off and so on through the stack. The relief in the board allows the last bottom a place to go. I can drill holes in 1/64" ply and never damage it with the bits I use. Aside from that I install the sleeves much the same as you. Once the center sleeve is in proper alignment with the wing root rib the rest is easy. I will show that process when I build it.

I found a light kit on Amazon and bought it, 2 strobes, 2 beacons, 2 landing lights and 1 ea. red & green, mounts and receiver patch. Wiring enough for 60 size planes so will be adding to that, $ 29.00 and free shipping, if I had a code I could have saved a few bucks. I also ordered the wing tube, 7/8" X 36" with sleeve, from TNT landinggear.

I redrew the rib locations on the plans, each side will have 16 ribs per scale, I have some to make and replace, some die cuts are not straight. As soon as I get the left window slides made I can start getting the fuse, sides together and stabilizer mounts in and work up from there.

Lots to do and I hope to have more pictures in the next couple days.

Leroy

Leroy Gardner

Flyer that's the beauty of a build thread done right, get others involved and share their ideas and pictures for me is what makes your build successful . there is so much to learn from others rather than just build your plane your way and not learn other ways that will make you better at your own build. I'm glad when other experienced builders step up and share with us all. There is a very experienced core group on RCU and I'm very happy to get some to follow my build and help when asked.

Thanks to you all, Leroy

Leroy Gardner

I just did the wing dihedral lay out on this Balsa kit for the wing tube size and it's 1.5 deg. per side, that's really not that much, with a wing tube your not going to be able to jack it up or lower it so get it right. a total of 3 deg. should be okey and I'm going with it. I do agree with Robert, some of the planes I looked at surely had more, I didn't see any that looked flat, but close. That could be another subject for discussion.

Leroy

Leroy Gardner

Richard it came from the distance wing was propped up following the instruction book, they never said it was 1.5 deg. but that's what it comes to with my Sterrett gauge. That is not an unreasonable number for this plane. If I remember right it's only 1.5" at the last rib not including the tip taper. I could double check for you if you like.

Leroy

stevegauth30

Don't be surprised if TNT takes a month or two to send you your tube and socket. I had to threaten to cancel my payment after five weeks before they finally put my order through and sent it. It took over six weeks from the time I ordered to the time I got it. Heard others complaining as well about it.

spaceworm

Hi Leroy, no, it is your plane and you flying it. I looked at dozens of full scale plane photos that show that most are flat. Adjustments to the dihedral can apparently be made with the struts, I did not know this. I have to get out my Sig 1/4 Cub plans and see what they called for in my Cub, it has been too long since the build. Dihedral will make it easier to fly, although the RC Cub was not intended or advertised to be a trainer. Flight protocol for the full scale and rc models call for cordinated turns using both ailerons and rudder for non skid turns. Perhaps the dihedral will reduce or elinimate the riudder input required. My Cubs are not hangar queens and both show the mistakes in piloting I have made flying them. Battle weary you migh say. Good luck with your build, I hope you don't put so much effort into building it that you won't want to fly it. Flying them is at least half the enjoyment get out this hobby/sport.

Over and out.

Sincerely, Richard

Leroy Gardner

Steve I can only speak for myself as I don't know what your hang up was, what I do know is Kathy and Tom are quality people and are not out to stick it to anyone. Another thing I know is they like others rely on their suppliers especially the wing tube sleeves. I wanted a 1" tube & sleeve and Kathy said they were waiting for 1" sleeves and would be a week before they had them so I asked about the 7/8" tube & sleeve which was in stock, I ordered it and it would be shipped today and I believe it.

I spoke to Kathy about some of the bad press seen on RCU and she was sorry for any of that but it's up to the customer to confirm status of stock especially ordering on the internet, a phone call will eliminate some of those delay problems. Personally I like them and their products, expect my order by the weekend.

Leroy

Leroy Gardner

Richard I have spent a few years as a certified A & E mechanic and had the wings off several cubs being recovered not to mention a lot of other work done to them and others. When the wings were put back on the tail was raised to level and struts put on using a level with a segmented bubble for dihedral which they all had some of. I have also seen high wing planes with anhedral, (slight droop) for what reason I don't know. Most high wings have dihedral to some degree but not near as much as a low wing, the mustang as an example has 10 deg. dihedral. Aeronautics is not part of A&E training which is called A&P today but I still learned something of it just working on many of them.

Leroy

stevegauth30

I'm not bashing them. Just my experience, was quite different. And I did, and do call before ordering. Guess I just have crap luck.

John_M_

Leroy, I suggest you take your time with the dihedral setup... one thing I noticed while building my cub, was the dihedral looked excessive, even though it was within scale dimensions... I ended up reducing it to where it looked good; don't recall what I set it too but I think it was 1 degree per wing... its one of those things that just goes out of perspective when scaled down, it just rubs the eyes wrong.


Here's a shot of my Cub taken with the ol chem film cameras back 15 years ago.. if I would have built it as per the plans, the dihedral would have been half as much again.


John M,

captinjohn

That is a nice looking Cub. Do you like how it flies with less dihedral? Thanks Capt,n

John_M_

Thanks CJ... its all torn apart now, and when I'm finished with it, it will look even better.

Regarding how it flys, that's a tough one to answer, because I don't know how it flew with the original dihedral... but the way you see it in that picture, it flew great... the J3 cub is a baby in the air, very stable... I use to fly it just below half throttle and just cruise around low and slow... the tail dragger ground handling on take off, takes some practice... if you jump on the throttle and are not ready for it, she'll dive to the left, so be ready on the rudder... slowly advance the throttle and steer with rudder until the tail comes up, straight down the runway, and she'll lift off when she's ready, don't force her off the ground or you'll be taking her home in pieces.


John M,

cubcrasher

My Feedback: (6)

Plus one on that dihedral thing. Every Balsa USA Cub I have seen looked like it had too much. Kinda like
it was a free flight model. The Sigs call for a little too much also. I always just eyeball them and if it looks
good I go with it. It doesn't seem to affect the way it flys. I don't put the scale effort that you guys do but
I have built a lot of the Sigs over the years. Leroy, flatten that baby out some. You don't want some guy
looking and thinking "man that is a nice build job, looks weird though with all that dihedral."

cubcrasher

My Feedback: (6)

Heres a little clipped action.

acerc

I'll add mine, it is a modified Sig clipped wing with "NO" dihedral.

John_M_

I really like that color scheme Ace, must stand out quite well in the air.

On the std J3 wing span, having "NO" dihedral at all, gives the wings a droopy appearance, maybe not so much with the clipped wing cub, but on the J3 you need some positive dihedral to make it look right... its these little details that really make it stand out scale wise.



What I think I'm going to do with my new revamped wings, I'm going to make the box the dihedral brace slides in at the wing spar root, a tight fit at the opening, but taper the slot on the inside... the load will still be on the brace, but allow some adjustment of the dihedral; that way I can use the struts to set both the dihedral and the washout if desired... more thinking to do.


John M,

Leroy Gardner

I will look at that dihedral again, while it's on paper now the 1.5" from root to tip just don't look like much given the length of wing. I think I'll make another trip to the airport and get a better prospective. John that picture you posted on #116 clearly shows dihedral and it looks good to me.

A little on the build: I cut all the slider slots for the windows in the sticks, the windows are styrene .030 thick with aluminum vertical bands, they both will slide and get pulls when finished. For the slot culler I found a neat set of Dremel type saw blades and the large saw was .034 wide and perfect for the slots. I jigged it up on the Dremel drill press and 3 passes in the spruce ( Dremel is no power house) got it done, those teeth on the saw blades are razor sharp, "oh" I got them at Harbor Freight $8.00, nice set with many uses. I also have some shallow slots I'd like to put in the cowling for the panel lines and cowl front, may end up doing the chart tape and primer but the cut lines would look more scale, we'll see.

Tomorrow I hope to get the door side upper wing saddle on and get the two sides layed up with the cross members and engine mount. I have plenty to keep me busy and winter finally caught up with us, I'll hibernate in my shop.

Forgot to mention that the lower window slide is not glued in, that will be done during final assembly, I have to be able to put the windows in first.

Leroy

Leroy Gardner

Spaceworm I'm going all out on this one with the details because I go to scale fly-ins where the planes are judged as well as the scale flying which is much about the pilot and awards are presented. I have 3 on two of my other planes, the modified Sig 1/4 scale Spacewalker 11 and my sold TF 1/5 scale gold kit built Mustang. These events are like no other, great planes and builders, I got hooked this summer but like the Sunday fliers too. Building is my winter love and I have a warm wonderful shop to do it in, it's called the dog house and I'm in it a lot.

Leroy

John_M_

Nice sliding windows Leroy

I think Ace has a good idea regarding how he sets up his dihedral with the enlarge holes for the wing tubes, and then gluing the hole doublers in place once you get the wing and struts in position... that way you can stand back a get a good look at it from a distance... if you plan on using those H9 struts, they're more than man enough for any loads you'll being putting on them... just check the thread fit on those aluminum clevis ends, mine were a loose fit, so I made new ones out of SS, the added weight was nothing to worry about.

John M,