Working on an orienatal build up and It was suggested to me to make the leadouts adjustable.  Has anyone done this on this plane? If so, would you mind sharing pics and comments?

Thank you
Mark

I would absolutely use adjustable lead outs on any stunt model as it is a very important flight trim feature.

I am currently building a SIG Banshee and installed an adjustable lead out guide. I am using one I purchased from Brodak.

I also have an Oriental ARF that came with adjustable lead outs from the factory.

Colin

So once you cover the wing you cant adjust them correct?  (I  am a newbie fyi) I just finished a Ringmaster s1a and went to this. 

Quote from: FlightRiskMK on June 18, 2026, 04:24:42 PMSo once you cover the wing you cant adjust them correct?  (I  am a newbie fyi) I just finished a Ringmaster s1a and went to this. 

Yes you can. The whole point of them being adjustable. You just have to carefully manipulate the covering around the completed slot opening and the lead outs. I'll try to find another pic from a different model.

Colin

A couple more pics from a SIG Skyray 35.

I would also install an adjustable outer wing tip weight box which is also an important flight trim feature. Also available from Brodak.

Colin

Ahh ok so you need a flashlight to adjust .. got it! makes sense.  So another question, why not just put them where the plans call?

Quote from: FlightRiskMK on June 18, 2026, 05:47:06 PMAhh ok so you need a flashlight to adjust .. got it! makes sense.  So another question, why not just put them where the plans call?

A model like the Oriental was designed a long time ago. The designers back in the day used somewhat conservative lead out locations for novice pilots. Farther back from CG is more conservative for line tension but may cause other flight issues and not be optimum for desired flight performance. The LO location on the plans 'may' be just fine, but there is no way to really tell until you fly the model. Options remain open if trim items are adjustable.

I have seen a few times where kit plans show a suggested CG location. And the centerline of the lead outs might work best at say 3/4" behind the CG. But once in the air one finds that the CG needs to be more forward to fly well. If that happens then the lead out location might also need a corresponding adjustment.

The amount of effort one wants to embrace in building a new model just depends on your ultimate goal.

Colin

Here's a kit-built Oriental wing with the adjustable leadout hardware installed. I left the slot fairly wide because the guide is inset a ways from the tip. The hope is to reduce rubbing during buffeting winds...?

Should I move the adjustable part more to the tip?  It's about 1 inch from the tip.  I haven't glued it yet due to my question.

Quote from: Colin McRae on June 18, 2026, 06:36:34 PMA model like the Oriental was designed a long time ago. The designers back in the day used somewhat conservative lead out locations for novice pilots. Farther back from CG is more conservative for line tension but may cause other flight issues and not be optimum for desired flight performance. The LO location on the plans 'may' be just fine, but there is no way to really tell until you fly the model. Options remain open if trim items are adjustable.

I have seen a few times where kit plans show a suggested CG location. And the centerline of the lead outs might work best at say 3/4" behind the CG. But once in the air one finds that the CG needs to be more forward to fly well. If that happens then the lead out location might also need a corresponding adjustment.

The amount of effort one wants to embrace in building a new model just depends on your ultimate goal.

Colin

My goal is to build this right.. whatever that is.  Keep in mind I am a newbie and lots to learn still.  Hoping to fly tomorrow at a local event.

Quote from: FlightRiskMK on June 19, 2026, 03:57:33 AMShould I move the adjustable part more to the tip?  It's about 1 inch from the tip.  I haven't glued it yet due to my question.

What is important is the allowable adjustment travel range for the 'centerline' of the 2 lead outs. I have only been using the Brodak lead out guide design where the 2 lead outs are set together (about 3/4" apart), and not independently adjustable. Looks like you have one where you can set the location of each lead out independently. I have not used the independent type so can't speak to the pros/cons.

Seems to me one would set the 2 lead outs at about 3/4" to 1" spacing from one another, then pay attention to the 'centerline' of the 2 lead outs in relation to the model CG location when determining the maximum travel range.

Concerning the travel adjustment range, it depends on the ultimate model CG location preference. I would start with the CG location shown on the plans, and mark where the lead out centerline is approx 3/4" to 1" behind the plan CG location. Then position the LO guide to give the maximum available adjustment range from there.

I have never flown an Oriental so don't know the 'optimum' CG location. If it were me, I would attempt to poll others first to see where they find the model to fly best and use that CG location verses what is indicated on the plans. That will probably give you the best chance of success.

Also important, once you set the max travel range make sure you trim all the ribs and any webbing as needed to ensure the lead outs do NOT rub against any wood no matter where the lead outs are positioned. 

And a couple other ideas for your build. I believe the design of the Oriental uses a 3" bell crank. You might consider upgrading to a 4" bell crank. And don't put in any fixed rudder offset.

Colin

Colin is 100% correct.  I *have* used independently adjustable leadouts and quit using them when I discovered that having them as close to each other was better.  There is nothing wrong with them.  Just more difficult to adjust in the field. The 3/4" aft of the CG is a really good starting point.  Place the set so that the maximum forward location of the leadout centerline is just a bit forward of the CG.  I have never had need to have the leadouts forward of the CG.  Please remember to trim the ribs.  Lead-out wire will saw through balsa and lockup controls in a couple of laps.  Also be careful of wing mounted gear.

Ken

Quote from: FlightRiskMK on June 18, 2026, 05:47:06 PMAhh ok so you need a flashlight to adjust .. got it! makes sense. 

Yes, they can be a bit difficult to adjust, but really not so bad. Just remember that the adj lead outs are a model flight trim feature. After you have flown the model a number of times and are satisfied with the flight performance, you pretty much don't need to adjust them anymore.

I have had models where I liked the lead out location. Then I have had pilots' way better than me fly my model and they suggested a tweak on the LO location. My model then flew even better after their suggestion. Something I would not have done based on my experience level.

Colin

Quote from: Colin McRae on June 19, 2026, 08:24:52 AMWhat is important is the allowable adjustment travel range for the 'centerline' of the 2 lead outs. I have only been using the Brodak lead out guide design where the 2 lead outs are set together (about 3/4" apart), and not independently adjustable. Looks like you have one where you can set the location of each lead out independently. I have not used the independent type so can't speak to the pros/cons.

Seems to me one would set the 2 lead outs at about 3/4" to 1" spacing from one another, then pay attention to the 'centerline' of the 2 lead outs in relation to the model CG location when determining the maximum travel range.

Concerning the travel adjustment range, it depends on the ultimate model CG location preference. I would start with the CG location shown on the plans, and mark where the lead out centerline is approx 3/4" to 1" behind the plan CG location. Then position the LO guide to give the maximum available adjustment range from there.

I have never flown an Oriental so don't know the 'optimum' CG location. If it were me, I would attempt to poll others first to see where they find the model to fly best and use that CG location verses what is indicated on the plans. That will probably give you the best chance of success.

Also important, once you set the max travel range make sure you trim all the ribs and any webbing as needed to ensure the lead outs do NOT rub against any wood no matter where the lead outs are positioned. 

And a couple other ideas for your build. I believe the design of the Oriental uses a 3" bell crank. You might consider upgrading to a 4" bell crank. And don't put in any fixed rudder offset.

Colin

What would a 4 inch do that a 3 inch wont? wow.. had to reread that one haha

Quote from: FlightRiskMK on June 19, 2026, 11:51:03 AMWhat would a 4 inch do that a 3 inch wont? wow.. had to reread that one haha

Better control leverage which means the effective flap movement is greater and the controls slower.

The stock 3" will fly OK, but fly better with a 4".

I redid the controls on a Nobler ARF. Changed from stock 3" to 4" bell crank. Flies quite well. (but I did have to cut into a bunch of ribs so the lead-out's cleared all wood)

Colin

Quote from: Colin McRae on June 19, 2026, 12:12:15 PMBetter control leverage which means the effective flap movement is greater and the controls slower.

The stock 3" will fly OK, but fly better with a 4".

I redid the controls on a Nobler ARF. Changed from stock 3" to 4" bell crank. Flies quite well. (but I did have to cut into a bunch of ribs so the lead-out's cleared all wood)

Colin

ok yeah i was thinking the same about cutting ribs
i may have a 4"

The adjustable guide can be inset from the wing outline a bit. One inch is not a problem. I would make the slot in the tip somewhere around 1/8" or a bit wider. If you subscribe to the theory that the guide MUST be at the outermost tip then you need to make a "moveable eyelet type" guide. Almost no one does those any more, but they work fine if your workmanship is good.

As far as the "need" for a 4" bellcrank in anything, there are reasons and then there is hype. What matters is control ratio between the handle spacing and the bellcrank leadout spacing, and separately, the amount of force available from one line opposing the aerodynamic control forces.

If you match your handle spacing to the bellcrank spacing, you have a 1:1 input ratio. That says that the motion of your hand equals the motion of the bellcrank. There is nothing magic about 1:1. Many guys fly with quicker, or much quicker controls. The old Hot Rock handle was wider and it flew a lot of 3" and 2" bellcranks. The higher the ratio, the smoother your hand inputs need to be. With trial and error, you can find out where you prefer it.

Another way to look at this is that if you have a certain handle that is common to all your planes, or if you are in love with a specific (perhaps non-adjustable spacing) handle, then you are picking ONE PART of control sensitivity when you pick the bellcrank size.

A lot of older planes were designed around the 3" bellcrank and it worked fine. Sometimes squeezing in a much larger bellcrank (3" -> 4") can cause new issues that may not be worth it, or done poorly could cause a crash. I reworked a handed-down SIG Twister that had bellcrank issues where the forward leadout where attached to the bellcrank was interfering with the leading edge. Clearance is needed. Details matter.

Where the 4" bellcrank starts to show value is when the line tension in one line is insufficient to move the controls against the air loads. Compared to the 3" crank, you increase your MAX force input by up to 33% with all other things being held equal. This really only matters under two circumstances: when the winds get really strong (and perhaps your plane is really moving out) and when you are maneuvering and your total line tension goes so soft that you are hoping for any kind of control. Neither of these would be what we should call "normal conditions."

Don't confuse this with control ratios between the flaps and the elevator. The bellcrank leadout spacing has nothing directly to do with that.


And the bellcrank size is only one half of the equation (or less) when someone is talking about "how quick" the controls are. Include all the factors and then it will make sense.

Quote from: Dave Hull on June 19, 2026, 08:39:27 PMThe adjustable guide can be inset from the wing outline a bit. One inch is not a problem. I would make the slot in the tip somewhere around 1/8" or a bit wider. If you subscribe to the theory that the guide MUST be at the outermost tip then you need to make a "moveable eyelet type" guide. Almost no one does those any more, but they work fine if your workmanship is good.

As far as the "need" for a 4" bellcrank in anything, there are reasons and then there is hype. What matters is control ratio between the handle spacing and the bellcrank leadout spacing, and separately, the amount of force available from one line opposing the aerodynamic control forces.

If you match your handle spacing to the bellcrank spacing, you have a 1:1 input ratio. That says that the motion of your hand equals the motion of the bellcrank. There is nothing magic about 1:1. Many guys fly with quicker, or much quicker controls. The old Hot Rock handle was wider and it flew a lot of 3" and 2" bellcranks. The higher the ratio, the smoother your hand inputs need to be. With trial and error, you can find out where you prefer it.

Another way to look at this is that if you have a certain handle that is common to all your planes, or if you are in love with a specific (perhaps non-adjustable spacing) handle, then you are picking ONE PART of control sensitivity when you pick the bellcrank size.

A lot of older planes were designed around the 3" bellcrank and it worked fine. Sometimes squeezing in a much larger bellcrank (3" -> 4") can cause new issues that may not be worth it, or done poorly could cause a crash. I reworked a handed-down SIG Twister that had bellcrank issues where the forward leadout where attached to the bellcrank was interfering with the leading edge. Clearance is needed. Details matter.

Where the 4" bellcrank starts to show value is when the line tension in one line is insufficient to move the controls against the air loads. Compared to the 3" crank, you increase your MAX force input by up to 33% with all other things being held equal. This really only matters under two circumstances: when the winds get really strong (and perhaps your plane is really moving out) and when you are maneuvering and your total line tension goes so soft that you are hoping for any kind of control. Neither of these would be what we should call "normal conditions."

Don't confuse this with control ratios between the flaps and the elevator. The bellcrank leadout spacing has nothing directly to do with that.


And the bellcrank size is only one half of the equation (or less) when someone is talking about "how quick" the controls are. Include all the factors and then it will make sense.

Thank you for this detailed explanation. I do like the 1:1 ratio since I think that will help me get started.  I do tend to be a someone that likes to set it and forget it.  Off to an event (free fly) and hopes to learn something and retain it

Thank you again and everyone that has giving me tips!

Quote from: FlightRiskMK on June 20, 2026, 03:25:27 AMThank you for this detailed explanation. I do like the 1:1 ratio since I think that will help me get started.  I do tend to be a someone that likes to set it and forget it.  Off to an event (free fly) and hopes to learn something and retain it

Thank you again and everyone that has giving me tips!

With the 4" bell crank I start out on a new model with a handle spacing at the same 4" which maintains the 1:1 initial ratio. Then adjust my handle spacing as needed based on flight performance. BTW, I use a dedicated handle and set of lines for each model. Once the model is trimmed and dialed in, I just go to the field, hook up and fly.

And yes, one needs to pay special attention to the build details. On my Nobler ARF control mods I needed to move the larger 4" bell crank a bit aft from stock (maybe 1/2" as I recall), so it cleared the leading edge. I had a previous Nobler ARF that I acquired already built that was stock (3" bell crank). The controls on my newer Nobler ARF w/ 4" crank is just smoother IMO.

Colin

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