ever body has a baby and i want one too!! SO.....

Here's something to consider that we've learned from one of our life long master model builders. That center spar running through the ribs is known as... brace yourself... the Rib Ripper. It has only one function known to modern pilot. That function is to shatter every rib in the wing, in the event of an otherwise benign beginner's crash. You may want to consider leaving it out. But before you decide, get advice from other Baby Ring builders. Just wanted to get that out there before you glued it in place.
Rusty

I second Rusty's comment. I have first hand experience with it ripping the ribs on my BRM. If you really want to use spars use 1/4" strips top and bottom. They are really not needed at all though. If it was me I would omit them. Are you using a solid leading edge?

getback wrote:... I am sure i'll need some more advice if possible later. try not to bother anyone with my issues but experience is always helpful Thanks guys, Eric

Eric, don't worry about asking too many questions. Ask all you want, that's what this forum is for.
Rusty

The baby ringmaster I just finished had 1/4' wingtips. Is that what the biscuits are?

Jim

I never use the Rib Ripper center spar, I do use the two 1/4" top and bottom spars and have never had a problem. The weak point of this model would have to be the nose. I'd build one out of wood.

getback wrote:

Cribbs74 wrote:I second Rusty's comment.  I have first hand experience with it ripping the ribs on my BRM. If you really want to use spars use 1/4" strips top and bottom. They are really not needed at all though. If it was me I would omit them. Are you using a solid leading edge?

 yes a 1/4 " balsa solid piece  I will omit that spar , and am I to sand the leader round or leave it pointed and cover?

I would sand the leading edge some, but not much. I would think somewhat pointy would cut the air a little better. The two wedges go on either side of the engine mount. From experience I would use triangular balsa blocks inatead. The little bits of balsa the plans say to use will fail the first time you nose it in.

Ron

Sand it to the profile of the fuselage cutout. It won't fit without any sanding. It shouldn't be pointed, and it shouldn't be flat. It should blend in. There is a lot of acceptable variability.

Solid cheek blocks that extend past the leading edge of the wing will definitely hold up better to some rough landings and light crashes.

Phil

Eric, I'm going to keep my fingers crossed on this one. While heating and twisting works, your wing appears at least from this picture to be really twisted. I would get a helper and a heat gun and really twist and apply heat. Remember, your dealing with a low temp covering that really is thin. It can and will burn a hole right through it. Hold it until it cools about 2 minutes. Sight the trailing edge because with certainty it will be bowed upwards. I use my pinky and thumb hooking the tailing edge to take that kind of bow out while applying heat. It may have such a bad torsional twist that it really is unrepairable unless you cracked some of the glue joints to release the stress. Good luck with it. Ken

Eric, was this a kit? I would like to offer some advice. I think your on the right track in terms of how to deal with it.  Kits or plans  with built up trailing edges and leading edges can be very problematic especially for someone returning back into the hobby or a new pilot. They're a real pain in the rear. They're very susceptible to the problems your experiencing and they're also extremely weak. Just gluing the pieces together can result in a warp that you won't remove once the glue is dry.  The Brodak Baby Flitestreak for instance  has a ridiculous leading edge. I looked at it and threw it right in the can. I have the luxury of making solid leading edge stock. However, the Brodak Baby Lightning Streak is identical in outline to the Baby Flitestreak aside from the tail feathers.  It also has solid leading and trailing edges not to mention less ribs. It can be built faster and it's stronger without the problems you just experienced. When a solid leading edge breaks, gluing the piece back together followed by a splice of 1/64" ply or 1/32" ply and some patched covering gets you back in the air quickly. When you have built up pieces, things tend to explode and this can be quite difficult to repair. I hope your able to get it straight enough to at least get some fly time on it. Ken

I like the built up leading edge Brodak uses. It is almost the same as the original Flite Steak kits used. It has a lot of advantages, strong, relatively light, no significant stress concentrations.

It DOES have a major disadvantage of being able to have a twist, warp or J-hook (hockey stick) built into it. It MUST be fastened straight to prevent this bad geometry, and can remove this character from the sticks the edge is built from...within reason.

How straight was the wing before covering? Sometimes it is better to remove the covering and try again, especially if the wing was good and straight to start with.

Phil

Here's mine, first engine i used a O.K. Cub .049A...motor was worn out after about a dozen flights, then used a Babe Bee, lol, notice glowhead and prop.

If the uncovered wing was straight, and covering caused this severe warping, then stripping the wing and starting over is best. Hand stretch and edge tack both sides, then shrink just what is needed.

If the wood was warped before covering, then the wood needs fixed. breaking joints is a choice. I would hesitate to make that choice, but sometimes it really is the best easiest choice.

Steaming or otherwise heating the wing and shaping it back will make HUGE changes in geometry possible, and it might be the best easiest way. Steam heat will often allow the plastic to relax some, but it wont be much. If the covering was over shrunk without any covering on the other side then it may force the wing to be stripped anyways.

Phil

Hey! You guys cant have all the fun makin' babies. I just happen to adopt one recently. Came with a "Desirable Golden Bee" motor. Holding it  up to the light it does not have that "Rib Rippin" spar and she looks nice and straight. The Desirable Golden bee, is just a well worn gold anodized tank with a sure start front end.The good thing is  now Ive got something to fly on the Fly it if you got it ringmaster day  when ever that is.

I love my baby's too, and bigger ones!

It might be the pic, but recheck the wing and H-stab are in the same parallel planes to each other. If the stab is canted it will want to come in/go out with up/down maneuvers making the plane grossly unstable.

The elliptical shape makes it photograph poorly.

Looking good. Went with the steam?

Phil