Author Topic: Confirming bellcrank neutral?? (Read 3037 times)

Jim Oliver · « **on:** February 20, 2008, 07:24:07 AM »

I have been puzzleing over the issue for a while, and have developed a means to "sorta/almost" determine the bellcrank neutral after the center section is sheeted, but would like to pick some brains to learn if there is a better way.

So, guys-----tell it, tell it all!!

Thanks,
Jim

Bill Little · « **Reply #1 on:** February 20, 2008, 07:31:19 AM »

Hi Jim,

I measure the movement of the wires at the tip. Then mark neutral on them. I try to be sure there is exactly (as close as possible) the same amount of movement in both directions so that the end result is valid.

Mike Spiess · « **Reply #2 on:** February 20, 2008, 07:40:18 AM »

I finish the lead outs to the same length before the center sheeting. That is the wingtips are installed before the center sheeting is done. Just my way. Ofcourse my wife says I do allot of things wrong

Clint Ormosen · « **Reply #3 on:** February 20, 2008, 10:15:34 AM »

Quote from: Mike Spiess on February 20, 2008, 07:40:18 AM

I finish the lead outs to the same length before the center sheeting. That is the wingtips are installed before the center sheeting is done. Just my way. Ofcourse my wife says I do allot of things wrong

Yup, that's the best way for me too. However, that's difficult to do on a foam wing model so the measureing method had to work for me on the 'Chip.

Bill Little · « **Reply #4 on:** February 20, 2008, 10:59:31 AM »

Quote from: Mike Spiess on February 20, 2008, 07:40:18 AM

I finish the lead outs to the same length before the center sheeting. That is the wingtips are installed before the center sheeting is done. Just my way. Ofcourse my wife says I do allot of things wrong

Hi Mike,

Your way is the MOST RELIABLE way, *if* you can do it, I totally agree!

A foam wing, though, doesn't allow it to be easily done........

Mike Griffin · « **Reply #5 on:** February 20, 2008, 09:13:40 PM »

Hey Jim,

You sound a little like Lewis Grizzard there. I do it like Bill Little does. Just use a sharpie to mark each line so I can tell where neutral is.

Mike

Ralph Wenzel (d) · « **Reply #6 on:** February 21, 2008, 03:57:14 AM »

Al Rabe described his system for solving this problem in a recent Stunt News.

He drills matching holes through the B/C, B/C mount, and fuselage top. to accept a 1/16" wire pin. When adjusting linkages and wrapping leadouts, he installs the Locater Pin to lock the control system. When finished, he removes the pin.

Jim Oliver · « **Reply #7 on:** February 21, 2008, 07:19:57 AM »

Ralph,

That technique is what I have determined to use on the next wing--didn't remember seeing it in the S.N. however.

On my current project, a Brodak Legacy, after busing and installing the bellcrank, I carefully cut the leadouts to the same length with the crank in neutral. Now if I can make the terminations accurately I will be OK, but being just a "little" obsessive/compulsive, I want a more positive technique.

Thanks,
Jim

wwwarbird · « **Reply #8 on:** February 21, 2008, 08:16:31 AM »

I usually find a reference point on the wing or fuse, anywhere can work, and put some sort of permanent mark on the pushrod.

Will Hinton · « **Reply #9 on:** February 21, 2008, 08:20:58 AM »

Even on the foam wings I do my leadouts before joining the wing halves. The BC needs to be installed in the spar first before joining anyway, so I install the spar in the inboard wing half, do the leadouts, then join the outer wing half to it. Works every time.
Will

Dave Denison · « **Reply #10 on:** February 21, 2008, 10:56:00 PM »

Great ideas all of them!

I'll add another, that has worked on both built-up and foam wings.

BUILT-UP: After the bottom wing sheeting is finished and some, has been applied to the top of the wing, center the bellcrank(B/C). Insert the B/C pushrod in the correct hole. Take 1" long stick of 1/8sq. and tack glue it to the edge of the trailing edge, the other end of the stick is tacked to the pushrod which is in isn't normal position. Check again for perfect position. Now comes the easy part.......take a 2 1/4" length of 1/16~1/8 m.wire, sharpen one end. Now from the bottom side of the wing push the wire thru the bottom sheeting and thru the "unused hole" in the B/C and thru the top sheeting, remove "stick" Funny, it takes longer to write about it that to do it. You now have "pinned" the B/C in the perfect position. The pin can stay in, right up until the sheeting is applied to the fuse bottom,or removed for wing install and then reinstall the pin.

FOAM WING: We are using the same idea again. This time the "gluing sequence" is important. Have the m.wire pin made (about an 1/8" longer that the wing is thick). Align and glue in the spar joiner with the B/C mounted. This is glued to the inboard panel. Fish the lead-outs thru and out the wing tip. After the glue is set, now set the B/C to that perfect position. Hold the B/C still and push the pin from the bottom, thru the "unused hole" in the B/C to the top of the wing. Again the pin can be removed and reinstalled at any time. This will allow you the feature of always finding the "perfect alignment"

I don't have photos of this procedure....yet. The next build will give me the opportunity. Happy to answer questions.

REGARDS. DAVE.

Bill Little · « **Reply #11 on:** February 23, 2008, 06:32:21 PM »

Quote from: Will Hinton on February 21, 2008, 08:20:58 AM

Even on the foam wings I do my leadouts before joining the wing halves. The BC needs to be installed in the spar first before joining anyway, so I install the spar in the inboard wing half, do the leadouts, then join the outer wing half to it. Works every time.
Will

Ah, but Brother Will, that means you have to do the wingtips before you join the wings! (at least one, and I always like to do wingtips last...... or at least a good while after the wing is already built! LOL!!!!! )

hmmmmm........... could it be I don't LIKE doing wing tips??? OH NO!!!!!!!!

Bill Little · « **Reply #12 on:** February 23, 2008, 06:34:05 PM »

Has anyone mentioned simply cutting the rough ends of the lead outs exactly the same before installing the BC?? Then all you have to do is measure from the ends.......

Naw, that's TOO easy...........

Wynn Robins · « **Reply #13 on:** February 24, 2008, 03:50:12 PM »

I install the Bellcrank and leadouts - make sure it is neutral and then put a bend in the leadouts about 10-12" out from the tip, this leaves a L shape on the leadouts.

Once you have sheeted the wing, and are ready to wrap the leadouts - you just line up the 2 Ls' and cut the leadouts to length........the wrap away!

Jim Oliver · « **Reply #14 on:** February 25, 2008, 07:53:57 PM »

What I have done previously is to center the bellcrank, much as has been suggested, and carefully cut the leadouts the same length.

As Bill said, too easy-------

Cheers,
Jim

MikeyPratt · « **Reply #15 on:** February 28, 2008, 10:33:53 AM »

Quote from: Jim Oliver on February 21, 2008, 07:19:57 AM

Ralph,

That technique is what I have determined to use on the next wing--didn't remember seeing it in the S.N. however.

On my current project, a Brodak Legacy, after busing and installing the bellcrank, I carefully cut the leadouts to the same length with the crank in neutral. Now if I can make the terminations accurately I will be OK, but being just a "little" obsessive/compulsive, I want a more positive technique.

Thanks,
Jim

Jim got it right. Cut the leadouts the same length before the bellcrank is installed in the wing, DUUHHH!!! Easy no hassel way to do it.

Later,

Mikey

Bill Little · « **Reply #16 on:** February 28, 2008, 05:16:08 PM »

Quote from: MikeyPratt on February 28, 2008, 10:33:53 AM

Jim got it right. Cut the leadouts the same length before the bellcrank is installed in the wing, DUUHHH!!! Easy no hassel way to do it.

Later,

Mikey

HEY MIKEY!!!!!!!!!!!!! I"M HERE TOO!!!!!!!!!!!!!!!!!!!!!! AND I SAID IT FIRST!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Re: Confirming bellcrank neutral??
« Reply #13 on: February 23, 2008, 08:34:05 PM »
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Has anyone mentioned simply cutting the rough ends of the lead outs exactly the same before installing the BC?? Then all you have to do is measure from the ends.......

Naw, that's TOO easy........... Grin
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LOL!!!!!!!!!!!!!!!!!!!!!!! love ya, Mikey.

Randy Ryan · « **Reply #17 on:** February 28, 2008, 06:09:32 PM »

This thread got me thinking. I always set up neutral with the leadout length, but its still a struggle sometimes to get everything zeroed out. Full size aircraft control systems all have rig pin holes to do it. On my next model, I'm going to add rig pins so I can individually set the sufaces and bellcrank and always have a reference back to zero.

Jim Oliver · « **Reply #18 on:** February 28, 2008, 07:12:42 PM »

Quote from: Jim Oliver on February 21, 2008, 07:19:57 AM

Ralph,

That technique is what I have determined to use on the next wing--didn't remember seeing it in the S.N. however.

On my current project, a Brodak Legacy, after busing and installing the bellcrank, I carefully cut the leadouts to the same length with the crank in neutral. Now if I can make the terminations accurately I will be OK, but being just a "little" obsessive/compulsive, I want a more positive technique.

Thanks,
Jim

Bill,
Not to argue the point, but post No. 7 contained this info.........

Cheers,
Jim

Dave Denison · « **Reply #19 on:** February 28, 2008, 07:30:10 PM »

Just a follow up on my early post ,on this topic. Randy's comment on full size aircraft use of "pinning positions".....this was my use of their application of "pinning".

I love the fact that after you pin the B/C, you can either build each panel separate, or as a complete wing and then add the wingtips later. The principal gives you many choices. I'll try to get photos posted soon.

REGARDS. DAVE

Bill Little · « **Reply #20 on:** February 28, 2008, 09:49:02 PM »

Quote from: Jim Oliver on February 28, 2008, 07:12:42 PM

My apologizes, Jim!

I missed that, that is why I posed the question....... Anyway, I was just funning Mikey since he hasn't answered a few recent posts that I replied to!!!! I am really pretty hard to miss in person, but I can completely disappear on the 'net.

Jim Oliver · « **Reply #21 on:** February 29, 2008, 07:49:40 AM »

Hey Bill,

No problem on this end-----always looking for more help!!

I have noticed that, sometimes, one person can say (post) the same info in with slightly different wording and cause us (me) to look at a situation in an entirely different way. Many times, this different view is the better view.

Cheers,
Jim

Bill Little · « **Reply #22 on:** February 29, 2008, 07:51:04 AM »

Quote from: Jim Oliver on February 29, 2008, 07:49:40 AM

Hey Bill,

No problem on this end-----always looking for more help!!

I have noticed that, sometimes, one person can say (post) the same info in with slightly different wording and cause us (me) to look at a situation in an entirely different way. Many times, this different view is the better view.

Cheers,
Jim

I hope we get to see each other over the next year or two.

Bill Gruby · « **Reply #23 on:** February 29, 2008, 08:35:00 AM »

Hmmm -- seems like a simple task? Pull one leadout all the way out and mark it at the wingtip. Pull the other leadout all the way out and mark the first leadout again. Now you have two marks. Pull the first leadout back out an measure and mark it half way between the two exhisting marks. In neutral belcrank the half way mark should be at the wing tip. At least I think it will be? Maybe that's too simple.

"Billy G"

Bill Little · « **Reply #24 on:** February 29, 2008, 12:56:20 PM »

Quote from: Bill Gruby on February 29, 2008, 08:35:00 AM

Hmmm -- seems like a simple task? Pull one leadout all the way out and mark it at the wingtip. Pull the other leadout all the way out and mark the first leadout again. Now you have two marks. Pull the first leadout back out an measure and mark it half way between the two exhisting marks. In neutral belcrank the half way mark should be at the wing tip. At least I think it will be? Maybe that's too simple.

"Billy G"

Billy G,

Tell Latimore to step away from the computer, he's playing again!

That one was covered somewhere in the thread above! (actually reply #1 by yours truly!

)

(hey, Jim! It must be something about being named *Bill*!!!

Bill Gruby · « **Reply #25 on:** February 29, 2008, 02:12:02 PM »

But "Billy Boy" --- I believe he said he liked hearing the same thing said in a few different ways.

When you said it you said lines, when I said it I narrowed the field, I said line. That's different ain't it?

"Oswald" ---- "Latimore went for beer"

Bill Little · « **Reply #26 on:** March 01, 2008, 09:20:09 AM »

Quote from: Bill Gruby on February 29, 2008, 02:12:02 PM

But "Billy Boy" --- I believe he said he liked hearing the same thing said in a few different ways. When you said it you said lines, when I said it I narrowed the field, I said line. That's different ain't it?

"Oswald" ---- "Latimore went for beer"

LOL!!!!!!!! my bad.....

I shoulda known it was Oswald....................

Mike Lauerman · « **Reply #27 on:** March 08, 2008, 03:06:11 PM »

Quote from: Ralph Wenzel on February 21, 2008, 03:57:14 AM

Al Rabe described his system for solving this problem in a recent Stunt News.

He drills matching holes through the B/C, B/C mount, and fuselage top. to accept a 1/16" wire pin. When adjusting linkages and wrapping leadouts, he installs the Locater Pin to lock the control system. When finished, he removes the pin.

BMW used this method in the '60s on multiple carburetor linkage on 3.0 litre engines. George Hurst also used it on his shift linkage. Al was running in good company...

Author Topic: Confirming bellcrank neutral?? (Read 3037 times)

Mike Griffin