Rib build QnA (I ask, you answer! :D ) - Page 5 - RC Groups
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Oct 07, 2017, 02:10 PM
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Extreme Sports: the cut-to-size coat hanger weight was 15g [as seen in the attachment]. The Alt. is 10g, so I think I'm going to use that. We don't have anymore bamboo skewers, but even if we did I'm concerned with having a wing spar that's not in a single piece. The two chop sticks I could use are 10g, but I'd have to cut part of another to get it to fit across the entire wing [not shown in the attachments].

Questions that relate to the attachments:
  1. Will the mini popsicle sticks work for control arms for the rudder and elevator? How do I get the holes in them - just use a power drill with the smallest drill bit?
  2. In regards to the old umbrella push rods: Should I use the long piece (the one shown that doesn't have the fabric attached is straight) or get the inside prongs that support the nose of the umbrella [not shown, but you should know what I'm talking about. If not, I can always get pics ]?
  3. I must apologize for being a complete newb, but will the wing spar not being exactly straight negatively impact flight? Also, where should I put the wing spar in relation to the KF Doublers? The plans show about an inch or two behind [I'll have to check the plans I printed off for the exact measure], but I want to be certain I'm doing things right so I practice the correct way and won't have to re-learn something in the future.
  4. Finally, in checking to see if the alt. wing spar would work for its initial planned use last night [pushrods], I found the holes on the servos a bit too small. How can I attach the umbrella rods to the servos and control arms? I've seen some sort of wire being used [piano wire, I think], but we don't have any of that. I just checked something, and I do have a large roll of weed wacker [a.k.a., weed eater] line I could use a significant portion of [i.e., length of line needed doesn't matter at all] - would this work, and if so how do I properly attach it (knot type [I can google it, but I do want to learn knots at some point anyhow], tape or glue, etc)? It does fit into the servo control horn holes, so all I have to do is properly get it affixed to it and I'll be Gucci! [I think that's the term kids are using nowadays to mean 'good'] Yes, still trying to stay relevant.
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Oct 07, 2017, 02:34 PM
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Extreme Sports's Avatar
Wow, only 15g. That's way, way lighter than I expected. How rigid is the wire? Maybe it's thinner wire than the coat hangers we get this side of the globe. It does not matter if it's not perfectly straight, as long as it does not distort the wing. But its job is to stop the wing from bending, so if you can bend it easily, it is probably not rigid enough.

That said, why would you not rather use a spoke from that umbrella? Usually they are made from springy steel that does not bend.

Still not clear to me why a normal wood dowel is not your first choice....should be available at any hardware store.
Oct 07, 2017, 02:58 PM
Registered User
Quote:
Originally Posted by Extreme Sports
Wow, only 15g. That's way, way lighter than I expected. How rigid is the wire? Maybe it's thinner wire than the coat hangers we get this side of the globe. It does not matter if it's not perfectly straight, as long as it does not distort the wing. But its job is to stop the wing from bending, so if you can bend it easily, it is probably not rigid enough.

That said, why would you not rather use a spoke from that umbrella? Usually they are made from springy steel that does not bend.

Still not clear to me why a normal wood dowel is not your first choice....should be available at any hardware store.
The wire is fairly rigid and doesn't bend much at all. I think it might have a coating on it or something to help make it more rigid, but I'll measure the diameter after lunch to give you an idea.

Truth be told, I didn't think about using one of the spokes from the umbrella. There look to be some bent spokes on the umbrella, but it may just be the force of the fabric - I'll update when I take the umbrella apart in a few minutes.

I was raised in a very frugal home where we learned to use what we have first. I guess that - combined with me wanting to fly this and not having access to a car or much spending money atm - is why I'm not willing to go to the store if I have stuff laying around that I can reasonably use.
Oct 07, 2017, 03:22 PM
Registered User
Extreme Sports: Yes, some of the umbrella spokes are bent, but I'll try to straighten one out after cutting it to size like I did the other two. Also, in the attachments you'll see the diameter of the metal coat hanger that I'm probably going to stick with if the umbrella idea doesn't pan out. The white metal alt. is too bendable for my tastes now that you point that out. Thank you
Oct 07, 2017, 03:32 PM
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Extreme Sports's Avatar
Fully support using what you have lying around. That can be half the fun.

I'd give the hanger wire a try if the umbrella spokes are all bent. Worst case you can replace it with something better later.
Oct 07, 2017, 03:54 PM
Registered User
Quote:
Originally Posted by Extreme Sports
Fully support using what you have lying around. That can be half the fun.

I'd give the hanger wire a try if the umbrella spokes are all bent. Worst case you can replace it with something better later.
Yea, and the umbrella spokes are a pain to remove. I'm just going to use them for the pushrods, but they still have a small piece attached that I can't get off.
Oct 07, 2017, 04:30 PM
Registered User
Just got the servo holes cut and checked to make sure in theory I've got them rotating correctly, as well as the wing put together. We're getting close!
Oct 07, 2017, 04:40 PM
Hot glue held together by foam
balsa or carbon's Avatar
Quote:
Originally Posted by FlyinWingFanatic
Extreme Sports: the cut-to-size coat hanger weight was 15g [as seen in the attachment]. The Alt. is 10g, so I think I'm going to use that. We don't have anymore bamboo skewers, but even if we did I'm concerned with having a wing spar that's not in a single piece. The two chop sticks I could use are 10g, but I'd have to cut part of another to get it to fit across the entire wing [not shown in the attachments].

Questions that relate to the attachments:
  1. Will the mini popsicle sticks work for control arms for the rudder and elevator? How do I get the holes in them - just use a power drill with the smallest drill bit?
  2. In regards to the old umbrella push rods: Should I use the long piece (the one shown that doesn't have the fabric attached is straight) or get the inside prongs that support the nose of the umbrella [not shown, but you should know what I'm talking about. If not, I can always get pics ]?
  3. I must apologize for being a complete newb, but will the wing spar not being exactly straight negatively impact flight? Also, where should I put the wing spar in relation to the KF Doublers? The plans show about an inch or two behind [I'll have to check the plans I printed off for the exact measure], but I want to be certain I'm doing things right so I practice the correct way and won't have to re-learn something in the future.
  4. Finally, in checking to see if the alt. wing spar would work for its initial planned use last night [pushrods], I found the holes on the servos a bit too small. How can I attach the umbrella rods to the servos and control arms? I've seen some sort of wire being used [piano wire, I think], but we don't have any of that. I just checked something, and I do have a large roll of weed wacker [a.k.a., weed eater] line I could use a significant portion of [i.e., length of line needed doesn't matter at all] - would this work, and if so how do I properly attach it (knot type [I can google it, but I do want to learn knots at some point anyhow], tape or glue, etc)? It does fit into the servo control horn holes, so all I have to do is properly get it affixed to it and I'll be Gucci! [I think that's the term kids are using nowadays to mean 'good'] Yes, still trying to stay relevant.
Yes , the mini popsicle sticks will work ..... just drill a hole in them for whatever you're using to attach to the pushrods . If you are using metal rods or wires for pushrods , just put a Z bend or L bend on the ends .... to fit in the hole on the control horn and the hole on the servo arm . If the push rod or wire is too thick to fit in the holes , you can attach something like a paper clip wire or safety pin wire to the ends of the pushrods . Use whatever you have to use , to attach the wire to the pushrod ... super glue and heat shrink tube , tape etc .

If you have an old wooden yardstick , that might make a good wing spar . Or sacrifice one of your good arrows . The most important place on the wing to have a spar is the center part .... where the wing is most likely to fold . It's not so important to have the spar reach all the way to the ends of the wings .
Oct 07, 2017, 05:04 PM
Registered User
Just finished gluing the wings to the middle back piece and the horizontal stabilizer / elevator
Oct 07, 2017, 05:35 PM
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Just got the wing and horizontal pieces glued in place. Had to remove the middle back and horizontal tail stabilizer and reglue separately due to them not lining up, but I think I've got them now.

E2A: and yes, I dry fitted it first
Oct 07, 2017, 05:58 PM
Registered User
I just need to add components now!
Oct 07, 2017, 06:02 PM
Registered User
Can I mount the motor just on top of the fuselage, or do I have to cut part of it away to get it set in some?
Oct 07, 2017, 07:03 PM
Registered User
All I need to do now is connect the servos up. Might not get the Maiden done today since I can't take this to the park on my bike.

Btw, CoG is good as well - @3.5" from the leading edge of the plane wing
Oct 07, 2017, 07:42 PM
Hot glue held together by foam
balsa or carbon's Avatar
Looks good !

Does the motor spin up and push the plane forward ?

If possible , show us a video of everything functioning .... motor/prop , rudder & elevator , etc . , with your movements on the TX sticks included . The two mistakes made most often are : prop on backwards & elevator movement reversed .
Oct 07, 2017, 07:50 PM
Registered User
I just sat down because my back be hurtin' lol. I had to switch two wires the first time I throttled up, but I felt for the thrust and there was more towards the front of the plane (very, extremely careful not to come close to making hand-prop contact). When I switched two wires and throttled up I could CLEARLY tell the thrust was going towards the back because the plane was already trying to take off while I was holding it!

When I moved the stick down the plane's nose would've pitched up, and when I moved the stick up the nose would've pitched down. I'll double check when I get up and will try to film it because now I'm second guessing myself..


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