A guy built me a debonair as a gift, all its needed is an engine and radio equipment, it calls for dowel control rods, how do you make em and is there an advantage over normal control rods?

They are lighter and supposed to reduce binding over long servo-surface distance. You basically replace most of what would usually be metal on the control rod with a wood dowel. Making them is easy, you take a wooden dowel which is roughly 4"-5" shorter than the whole distance between the control surface and the servo. You then glue metal pushrods to the ends of the dowel to complete the needed length. Ive seen it done by wrapping string around the dowel to secure the metal pushrod. About 2" over the wood will do. Then use epoxy to harden the string.

You can always use metal pushrods and there wont be any trouble.

The advantage is that they can be lighter, and they won't flex as much over long distances as steel (unless the steel is in a tube supported every 5 in. or so).

I haven't actually made them, they've come with some of my arfs, but I've chosen to replace them with properly supported metal rods and nylon tubes. You can use whatever kind of push rod you like, as long as it's properly installed.

"Normal" control rods were dowels in the past, they are very thrusty. You only have to cut them to the necesary lenght, make a hole to insert part of the wire rod, glue the parts and add a shrinkable tubing.

Follow step 21 of the Super Stick manual which uses dowel rods to have a b etter idea:

http://www.horizonhobby.com/ProdInfo...700-manual.pdf

lol...some arf still comes with dowls as control rods

It's cheaper too, plus a 24" metal rod usually arn't lone enough

You just purchase regular metal rods and just cut them and connect them to the dowls.
You can wrap threads around the rod/dowls to secure it. Just use CA or epoxy.
You can drill holes into the dowl...but you don't need to.

If you want threads for the cleves on both ends...just buy shorter rod the threads/cleves on them.
If you want cleves on one end and a hook on the oposite. Just whack a 24" rod.

I was going to say the same thing.

Just drill a hole about 1 1/2 (One and one half) inches from the end of the dowel, then cut a "V" shaped notch from the hole to the end.

Make a 90° bend in the wire 1/4" from the end and insert that bend into the hole so the rest of the wire rests in the "V" groove.

Now wrap the hell out of it with plain ol' sewing thread, then smear some glue on it (Wood glue, CA, or whatever you like - I like thin CA but it makes a lot of fumes)

Do the same to the other end. Then bend the wires however you need them.

Note: you'll want to measure how long it needs to be before starting. If either of the wires has no threads, leave that one long so you have room to "cut to size"

The wood dowel control rods are NOT light weight. As a result, when you make a hard landing or crash, the inertia of the dowel may strip the servos. I prefer the nylon Nyrods. If you are into precision acrobatics, which I'm not, you will need something more accurate and consistent, like dowels. I believe carbon fiber rods weigh a lot less than the wooden dowels.

Hi!
Carbon rods ...or wooden or aluminum are good, But best is thin fishing steel vire.

And it's sensible to support dowel rods at least once along their length.

All pushrods with any length should have some support along their length.

Today I have to buy them but at one point I had A lot of friends that hunted with A Bow. Free Carbon Fiber rods in stock all the time and in different thickness and length too. Arrows are A very cheap item and if you know anyone hunting with A Bow then they tend to Robin Hood A lot, that kills there arrows and they are A throw away. I do like the Rock and install an Almost support, it almost touches the shaft but not quite. Carbon fiber doesn't warp or flex like the wood shafts. I make mine up different then Minn but the way he showed is just fine and A lot easier too.

What?!!!!

Where did this come from?


Try weighing them sometime and compare the weight to a thick CF rod. Not much of a difference.

The rods should NEVER move laterally, if they do the CONTROL SURFACE ( not the servo horns ) will move, introducing a blow back type response.

Think about it, and you'll realize that this is the case...

Nylon rods bend latterally so unless they are supported through the fuse at various points, the can give the most and even cause flutter on a model that otherwise would not.

Dowel type control rods are the simplest and cheapest way to do it, unless I'm putting together a big gasser, I like to use the dowel style, just for convience and strength. Carbon is good and plenty strong, but the joint where the metal connects to the rod must not stress the outter carbon tube, otherwise it will crack the carbon fiber tube and fail. Nylon is good for small aircraft that has light control surface loads, unless you buy the big honkin huge nyrods, for the arrow shaft method, buy the dave brown end fittings and plug the wire into them. On your trainer, just do dowels with wire method, I perfer wrapping them with thread, heat shrink tends to be a little weak for my liking, but that's my own oppinion.

Hi opjose
There are different view points on this. If my model can work OK with Nyrods I tend to use them. In a crash the Nyrod tends to put a smaller load on the servo than a wood or carbob fiber rod because the inner Nyrod rod weighs a lot less than the wood or carbon fiber rod. No need to get excited here. It is a minor point. I have stripped a number of servos thru the years and have studied what is causing that and if there is a way to reduce this. Because of my training, education, and career I happen to be comfortable thinking about the differences in the inertia of the two methods. I think I may have made some improvements in some of my models because of this. Others don't. I'm happy either way. Most people are not comfortable thinking of inertia in a dynamic situation such as a crash. The planes will fly either way. It has little importance and need not be considered. I do.

I think if a crash is bad enough to cause the pushrods to strip the servos, then you have a lot more to worry about than stripped servos!

yeah what I am thinking of normal is the metal control rods, i forgot about the nylon control rods

Villa:

Sorry, but a mistake made quite often with model RC planes it to apply larger scale scenarios, which tend to scare the RC enthusiast.

This is one of those things.

Wooden control rods have been in use for some time as they are quite effective and safe.

You are ( now ) refering to "G" forces experienced in a crash versus actual in flight behavior which was the original discussion.

While it is feasible that any extra weight, even a few grams, can through "G" loading, in an abrupt stop, help increase the risk of servo stripping... The amount of force this would require and produce will effectively obliterate any plane. The plane would disappear.

Most dowel pushrods weigh in at under .3 oz. A 30 G crash would produce 9oz of force at the servo. Even a standard servo has no problem with this. Indeed any servo that suffices to prevent blowback in a model would be safe.

Dowel pushrods tend to be used in mid-sized or larger flyers. Typically we use higher torque servos in these planes. Here the "G" forces exerted in a crash have a lesser effect due to the higher strength servos.

While you may have experienced servo stripping in the past, it is likely NOT due to the presence of a dowl pushrod.

1/4" or 5/16" dowel pushrods are fine when put together as Minnflyer shows. You can also cut a strip of covering to replace the shrink tubing and iron on a couple-three wraps if you don't have heat shrink tubing available. The only thing to watch for is the grain of the dowel is straight, otherwise the strength could be comprimised. For smaller lighter models (below 40 sized) 1/4" square balsa works well if firm and also staight-grained.

I have to agree with HighPlains. I never use anything but dowel pushrods. I've used everything over the years and always come back to dowels. Pine for large models and balsa for small ones. I prefer cable for rudder on large models but occassionally still use dowels. I always run a few horizontal balsa "sticks" above and below the dowels down the fuselage on larger models just to keep the engine vibration from setting up a vibration in the dowel. The only issue is that the servos sometimes need to be stepped one higher than the other because if you cross the dowels to help with the fuselage exit alignment, the different level servos will keep the dowels from rubbing each other.

Paul

here are some off topic questions, some might be a bit dumb

1. How do I center the mount on the firewall?

2. I was told to put fingernail polish on the firewall, what is it for?

3. This is the dumb question, Which is correct, push rod or control rod? ( this would be a good poll question)

I also may apply CA under the heat shrink as an added measure. By the time I do this I KNOW the dowels are of the correct length.

flyboy

draw a x on the firewall from corner to corner, then you have the center, if it is a commercially available mount it should have a template and use that,

the only reason I can see is to fuel proof the firewall, if it is plywood. I would paint it with thinned epoxy, if it is plastic cutting board, wich i prefer, there is no need

and it is a control rod, it pushes and pulls..................whatever

check out the plans on www.spadtothebone.com

Debonair is one of the best designed trainers, flies really good and TOUGH