What do you think of this??

LAST EDITED ON Oct-18-04 AT 10:45 PM (CDT)
 
I know it's a bad picture. But it shows the crimp attachment of the leadout wire to the nylon bellcrank in my ARC Cardinal. Wonder how long it will take for it to grind thru the bell crank with my LA 46 on board. I plan on fixing mine. I admit I am disappointed.

Hmm... Well, it's not the way I would do it.

I'm kind of skeptical about some of these reports of bellcrank failures. People flew for years with the old Veco/Fox bellcranks. They would wear, and the holes would get augered out eventually, but it usually took a very long time. The advent of nylon bellcranks with cable leadouts offered even longer life and reliability.

That picture appears to be of a nylon bellcrank with a cable leadout. If that's true, I would expect the combination to last a very long time. If the crimp was improperly done, that might be a weak point, but your post didn't target that item.

Why aren't more people using the piano wire leadouts with nylon bellcranks? That seems like the longest lasting - smoother, too. I'll admit, though, that I don't know much about the latest control line "science" yet.

These days I bush my bellcranks but I used bare cable through nylon cranks for quite a few years without misshap.

The last one worked well for about 200 flights before I crashed the 40-sized stunter. My autopsy found no control system problems within the destroyed aircraft. The only defects were in the pilots head and hand.

I agree that solidly doubt would work better with a nylon bellcrank but we all know the downside. Solidly leadouts can be a pain in the butt to deal with.

These days, I use flexible lead outs combined with bushings in the bellcrank arms.

BIGS

" What constitutes the dignity of a craft is that it creates a fellowship, that it binds men together and fashions for them a common language. For there is but one problem - the problem of human relations."

Greg,
I just finished my arf Cardinal. At 40 oz. with a OS .40
lA and 4oz. tank. I can't wait to fly her. I'm not to worried about the leadouts eather. A $100 airplane, especialy the 1st. The first one is really a trial one don't you think? I,m waiting for the 1st. post that says the leadouts broke at the bellcrank or the wing tip.
Then if I get anouther one I'll modify it. As for now I wouldn't worry about it.

I think this is one benefit of choosing the ARC. You can see what there is to see, and fix it with minimal sweat, if you don't like it. An extra hour isn't a big deal to save the rest of the time and money invested. I plan to change the leadouts, sleaving them where they go through the BC, then bind with copper wire. My OrientARC came with dual adjustment type leadout guides, which will get replaced also. It's my choice and it's easy to do while doing the leadouts. I'm kinda surprised it's that way, actually. CardinARC should be here by Friday...and it will get the same look.

Anybody know if the parts are laser cut in Pennsylvania, or China? Who picks out the balsa? My OrientARC isn't particularly light. Maybe tomorrow night, I'll pile up all the bits and get a total. Steve

> My OrientARC came with dual
>adjustment type leadout guides, which will get replaced
>also. It's my choice and it's easy to do while doing the
>leadouts. I'm kinda surprised it's that way, actually. (snip)
>

I am with you on this. I have never understood the reason for the dual adjustable guide. You want the leadouts as close together as possible without fear of binding. So a dual guide now means you have to move two, but you still move them as close together as possible.

>Anybody know if the parts are laser cut in Pennsylvania, or
>China? Who picks out the balsa? My OrientARC isn't
>particularly light. Maybe tomorrow night, I'll pile up all
>the bits and get a total. Steve
>

I asked about this thinking maybe John did the cutting and sent the parts to China for assembly. Wrong! It turns out they are cut in China which means they get the balsa shipped directly there, too.

>Greg,
>I just finished my arf Cardinal. At 40 oz. with a OS .40
>lA and 4oz. tank. I can't wait to fly her. I'm not to
>worried about the leadouts eather. A $100 airplane,
>especialy the 1st. The first one is really a trial one don't
>you think? I,m waiting for the 1st. post that says the
>leadouts broke at the bellcrank or the wing tip.
>Then if I get anouther one I'll modify it. As for now I
>wouldn't worry about it.

The problem is not just the plane, but I don't want to smash up my favorite motor also. Actually was planning to use a ST 46. But now I won't take that chance.

If that is stranded wire my estimate is 50 flights.

I guess we will see. I will keep track off my flights.

> If that is stranded wire my estimate is 50 flights.

Sorry, no dice there. I've had several planes with hundreds of flights on a Brodak nylon bellcrank, and no detectable wear.

Tom Dixon's original Time Machine prototype had over one thousand flights on it with that bellcrank setup. It held just fine. If people want to change the leadout setup, thats just fine if it makes you sleep better. But I see no evidence that it is needed.

That looks like Brodak bellcrank. I use them for longtime. I had a chance to inspect it after my crash in Muncie - it was my #1 ship so it was after many contest pulltests. I did not find ANY sign of wear. However I always use wire instead of cable.

I would say if it is good material and the model is not heavy, it will survive also with cabel. BTW also the cable can have problems, it consists of thin wires and it can wear much quicker then single wire of the same thickness. Warning for me was black oil in eyes of that bellcrank after crash. It means it contains metal from wire. Those new plastic materials contains glas, it can eat hard metal without problems.

I think it should not be too much problem to replace it by some wire eye.

LAST EDITED ON Oct-19-04 AT 07:16 AM (CDT)
 
While all the fellows who fly better than I do highly recommed the use of a bent tubing bushing when using cable leadouts in a nylon bellcrank, I have my experience to report. My current Banshee has been flying with flexible leadouts in a stock 3" SIG Nylon bellcrank for over 15 years. I also have a thirty plus year old CG Shoestring with a 3" Top Flite Nylon Bellcrank with cable leadouts that has not given me any problems as a result of the control system. Both these planes were built before I knew any better, and they are still flying well.

I must say that, were I to do those controls today, I'd heed the advice of those better flyers and bush the bellcrank somehow, just to be on the safe side, but my limited experience does not indicate to me that I should cut into either plane and redo the control system. If I had an ARF Brodak Oriental or Cardinal set up the same way as pictured, I wouldn't cut into it to redo the control system either. I would replace the leadouts in a TF ARF Nobler in a new York minute.

As further evidence this may be a tempest in a teapot, I'd think that the commonly available adjustable leadout devices would be a great deal more susceptible to leadout "sawing" than bellcranks. Those braided, highly abrasive cables do, after all, actually move back and forth in those guides in a sawing motion a much greater distance than the pivoting motion one would see from the cables acting within the bellcranks. How often do those devices fail? I've yet to see any noticeable wear on those that I've installed.

If my Nobler ARF had been done like this, I would have left it alone. I have Veco, Fox and Perfect bellcranks that were never bushed. They have very little wear. Back then my engines were leaned out to run fast and pull hard. If I had a Brodak ARF setup like yours I would go ahead and fly it. Now scratch building or doing a kit I would bush everything. Later, DOC

PS:If you are just learning the pattern, you may be putting pieces back together anyway.

>I just finished my arf Cardinal. At 40 oz. with a OS .40
>lA and 4oz. tank. I can't wait to fly her.... Greg Hart

Greg,
I'm curious as to how you like the .40 LA on the CardARF. I'm guessing that you're waiting for the rain to stop so you can fly it. Haven't picked an engine for mine yet.

Thanks,
Kim Mortimore
Alameda Aeronuts

Greg... I left mine stock. I don't thinks it's going to be a problem. I wish the nose had been made from "Unbreakium" !

"I wish the nose had been made from Unbreakium" !

I agree Divot Dick, I've seen you fly befor and you could sure use it!! (Tanager)

I have experienced lead out failure one time in over 40 years. It was on the Fancy Pants that I reviewed in Stunt News.
The metal B/C sawed through the down line cable. Through a miracle it resulted in minimal damage.
The plane is still flyable today, with patches to the lower wing covering.
Bill <><

It seems clear to me that the stock setup pictured will work well and reliably. Personally I could not stand to have such a setup, simply due to not trusting someone unknown to me doing the crimping, a job quite easily muffed in variuous ways. Yes, even with proper tools.

While I do in fact used bushed leadouts, 1/16" brass tubing bent into a long, narrow "U," it has little to do with reliability. A very cleanly drilled hole in a nylon bellcrank, hole properly and lightly countersunk, will result in a slightly smoother control system over life of the model, again with brass bushings on leadouts. A bit of motorcycle chain lube helps as well.

For what it's worth, on anything larger than a 35-sized model I use either the Tom Morris or Windy bellcranks, kinda preferring the latter when ends are run through a table saw and so "forked," leadout attachment being with long-shouldered 4-40 grade 8 cap screws.

LAST EDITED ON Oct-19-04 AT 02:16 PM (CDT)
 
I use the 1/16th tubing on my cable L/O, but do very little to the solids I use other than to make sure there are no sharp bends in the wire. I have never experienced a failure with a nylon or phenolic B/C, and therefore I no longer use any metal bellcranks. Just personal preference.
Bill <><

Greg,
I normally have some wise remark to make but I also have some experiences to share. I started flying around 1951 or '52 and have built and flown several ships from 1/2A to .60s In all of those I have never personally had the type of failure you questioned. I have seen failures due to crimp failure, solder failure, music wire that rusted thru to failure, pushrod keepers that didn't, belcrank mounting bolts that came out, belcrank mounting platforms that pulled out due to fuel soaking (long time for that one). I have heard people on this forum mention belcrank cut thrus but never seen it. So, I guess, I would not be too concerned with what I see in the picture. BUT,, I also know that if I AM concerned about a potential failure, whether real or imagined, I make an effort to avoid it. SO if you see this as a concern, change it to satisfy yourself... Remember it's not our airplane we're talking about, it's yours..

I have been flying a Brodak Cardinal that is kit built.I did not bush the bellcrank so it is just like the photo except I wrapped the cables rather than crimped.It has about 200 flights at this point now and all seems well.It has the stock Brodak bellcrank in the plane.I have pulled a sig bellcrank out of a old plane that had many a flight on it,with cables grinding away on the nylon.I could see no visable wear?I will admit that my new planes are getting the Windy bellcranks in them but I see no reason that these will cut through the bellcrank in 50 flights!I would be more concerned with the crimp!Do a good pull test on the system before assembly?

The only problem I ever encountered was with a non bushed metal (Perfect) bellcrank and cable lead outs which were not sleeved with brass tubing, and the cable broke.
I haven't used a metal bellcrank for years because I am too lazy to bush the holes when the nylon/phenolic ones never see to wear out or damage the lead outs whether they are cable or solids.
Bill <><

Greg,
In the Picture that you posted, it looks as if there a shinny spot on the sleeve, is this solder?

>Greg,
>In the Picture that you posted, it looks as if there a
>shinny spot on the sleeve, is this solder?
>
>Mike Clark

Hi Mike,
No, the shinny spot is just a reflection off the crimped sleeve. There is no solder in any of the control system. Each sleeve was crimped in 2 places. I have seen the cable work it's way thru aluminum bellcranks so I was a little paranoid when I saw the stock attachment. It seems that those in the know say it's not a problem.

My kit-built Gieske Nobler had stranded leadouts through the nylon bellcrank. After about 10 years, but not a huge number of flights, one of the leadouts failed right at the bellcrank. The other one was just about ready to go as well. The bellcrank itself looked fine.
Of course I was flying over asphalt, and the plane and motor were both destroyed.
Pat MacKenzie

SO if you see this as a concern, change it to satisfy yourself... Remember it's not our airplane we're talking about, it's yours..

Well, Mr.66RAGMAN your right. I just couldn't sleep nights so I took the Stock bellcrank out and installed a Tom Morris unit in it's place.
Thanks to all of you and you input. Sincerely

You might be interested in what Gary Nelson will tell you of Stranded cable-nylon bell cranks.

> You might be interested in what Gary Nelson will tell you
>of Stranded cable-nylon bell cranks.

What is this, 20 Questions? We don't see Gary here much; why don't you tell us in his stead?

Whoa! I just remembered that Don McClave had a real nasty experience with this sort of combination. Hmmmm...?!

Where *were you* at Fall Follies? I had like 6 gallons of home-made blue berry ice cream, a whole 1/2 gallon on reserve just for you!

You might be interested in what Gary Nelson will tell you of Stranded cable-nylon bell cranks.
John Leidle

Yes, I might be??

Blue Berry Ice Cream? My favorite. Any way Gary built a Stilleto in 1994 or 1995. He had a ST .46 in it ,the plane was white & Blue . It flew about 40 to 70 flights and it had a nasty accident splattered face down on the asphalt at the Boeing space Center.Upon further inspection they found the stranded cable just hacksawed through the nylon belcrank. If I use stranded cable I use an eyelet to wrap the cable around.then notch out the bellcrank to accept the eyelet. Or I would use SOLID music wire to go through a bellcrank.

Paul Walker witnessed this mishap. The poor Stileto looked like Humpty Dumpty.

Nobody offered me any blueberry ice cream. The onions were nice, though. Thanks.

I have seen one saw-through of a nylon bellcrank, and one where the arms broke. Both were Fast Combat planes. The first was at a Nats, it was Gil Reedy's model and it was fairly old, not having been flown for some years (it had a wooden boom, everone else had gone to arrowshafts). The second was at a Dayton, OH contest - a SIG bellcrank. Both resulted in flyaways and crashes.

That said, I've never had it happen to me. I use external controls, and can see if any sawing is taking place, and I recycle my bellcranks when planes get destroyed. I've got a big box full of the SIG bellcranks, which I'll probably never use up in my lifetime.