rustyrivet

My Feedback: (6)

I'm getting ready to build a Ace Big Bingo. Can I replace the 11 lite ply ribs in each wing half with hard 1/8 balsa? The kit's lite ply ribs already have 5 fairly large lightening holes cut out in them. If strength and structural integrity was so important, then why did they do that? (You should see how close the lightening holes are to the notches, and rib edges in some places).

I am not familiar with large birds nor have the flying experience yet to judge if this plane was designed overly heavy, or this type heavy construction was necessary. (I love building, and sombody else will fly it) I can sure tell you that I am not pleased either with the 5/8" O.D. diameter cpvc water piping that is used for the leading edge. It weighs a freeking ton! If you think it's safe, I'll replace the lite ply ribs with 1/8 " hard balsa, and I'll probably replace that pipe leading edge with something lighter too.
A Moki 2.1 engine and a 32 Oz tank will be powering this bird.

So what do ya say?.....leave it alone, or stick in 22 new balsa ribs, and a new L.E.??

SST

My Feedback: (2)

I doubt if you'll save much weight with the ribs, but Lone Star Balsa sells 5/8 Carbon Fiber tube that has to be lots lighter than PVC...

Tall Paul

I have a Big Bingo kit.... and I'd throw out almost the lite ply. The thing must weigh a ton built per plan!
Seriously overdesigned!

rustyrivet

My Feedback: (6)

Paul,

You're one of the few that has this 10 year old kit, and so you see exactly what I'm talking about. If I cut new balsa ribs with the front of the ribs cut flat faced (instead of a circular cut out like on the existing kit ply ribs), then I can use a table saw to split a 5/8 wood dowel right down the middle. I can then glue the round faced half of a dowel to the front of the ribs. (instead using that heavy CPVC water pipe that comes with the kit.)

Doug,

I have already cut a sample 1/8 balsa rib with smaller lightening holes. I have also weighed half of a 5/8" wood dowel v.s. the cpvc pipe that comes with this kit. I WILL END UP SAVING 1/2 A POUND! Tht's worth the extra fussing.( 4oz with the ribs and 4oz. with the leading edge.)

I just don't know if those heavy lite ply ribs and tough water pipe leading edges are necessary in this aerobatic plane for structural integrity.

The owner of a local hobby shop used the simple logic "If they designed it that way, then use it that way". But you and I know there's plenty of flaws in kit engineering.

I get a kick out of that new Giant Top Flite P-51 ARF. The thing is 2 - 3 lbs lighter then the Kit of the same sized plane!!!! Talk about cutting out excess and needless weight!

SST

My Feedback: (2)

There is no way I'd use even 1/2 a wood dowel with CF available.

Tall Paul

Looking at the plans, I'd not use: the lite ply trailing edges on the wing, the lite ply wing center section sheeting (1/8" balsa out one more rib bay on each side..).. the lite ply centers for the horizontal and vertical, the lite ply outer fuselage sides. All these will be 1/8" medium balsa.
The CF tube leading edge is another must-do!
And I'll be mounting the landing gear in the wing. Makes for a more controllable takeoff.
The motor will be a US Engines 35cc.
.
Shoot, almost got a hernia picking up the box!

rustyrivet

My Feedback: (6)

Well, I love building planes, but not flying them! I only recently started putting a big one together from plans that's is now almost complete after a year and a half. I only have beginners experience flying with 60 size trainers too. No low wings as of yet.

So I don't have enough experience to make my own judgements with the construction and engineering of this plane, without knowledgeable input from others. But I have heard enough about this plane mentioned here on RCUNIVERSE to know it's FREAKING HEAVY. I also have enough common sence to recognize there's a whole lot of ply and heavy water pipes on this thing. Pipes are what you balance and walk on up in your attic, and ply is what holds your roof on during 60 M.P.H. winds. Strange stuff to use extensivly in a toy plane!

I'll check the carbon fiber tubes at Lone Star. But don't forget, even aluminum or titanium will be just as heavy, or heavier then CPVC plastic, if the walls are thick.
I already checked 5/8"O.D. aluminum Gator Tubes with .035 wall thickness. They are actually heavier then the cpvc pipe that is supplied in the Big Bingo kit. I suspect the carbon fiber tubes in 5/8" OD will not have thin light walls either, and will be as heavy as these sorry cpvc pipes. Only K&S makes thin .014 wall tubes, (39" long as needed) but they want to sell me a minimum $85 worth !!!!!!

Anyway, I'm taking the plans to another Hobby Shop where an older experienced gentleman who has been building large scale plans all his life works. I can run your suggestions by him for final approval. THANKS FOR THE INPUT!

PS I've been hauling that box back and forth around the house everywhere. And all this time I thought I got my dislocated discs at work!