crashed2

My Feedback: (4)

WOW, I don't know if I like the new look of RC Universe!

I am scratch building the Pondmaster that was featured in the June issue of RCM Magazine, and in the article they used monocote hinges. For the life of me I can't figure out how that is done.
Could someone please give me a clue!

Thanks!

William Robison

My Feedback: (3)

Crash:

Go here:

http://www.rcuniverse.com/forum/m_10...tm.htm#1057345

It's all explained, and Cabanestrut has appended a good illustration.

I found it with a search on "Covering" and "Hinge."

Bill.

Dsegal

Also take a look at http://www.rcuniverse.com/forum/m_33...tm.htm#338086/

With the method described in William Robison's link you must be sure to allow a slight gap between the surfaces or you will not be able to deflect the surface downwards. The Higley's suggest using a cardboard shim after you roll the aileron up and back in order to create a small gap.

Dsegal

Another approach is to make rolling hinges from strips of covering material. These are practically frictionless and if done for the full length of the ailerons will seal the gap. And they will hold onto the ailerons more strongly than any other method. Hard to describe in words, but here goes.

The aileron is held by adjacent strips of covering material (matching that on the wing and aileron) which are placed close alongside each other from one end of the aileron to the other. A strip will start on the top of the wing, go down through the gap and then adhere to the underside of the aileron. The next strip starts on the bottom of the wing and goes up through the gap to the top of the aileron. And just keep going.

The trick is how to get the adhesive to switch sides as it goes from top to bottom. This requires each strip to be made up of two pieces of covering joined, adhesive to adhesive, where they touch. The width of the overlap is critical and should be worked out by sample tests. The overlap must be great enough so that no adhesive touches the LE of the aileron or the TE of the wing. This is critical- you do not want the strips glued to the hinge area so the strips can just bend gently or "roll" as the aileron moves. But if the overlap is too great they will tend to stick up from the wing surface. Easy to work out in a few minutes.

The good news is that the strips can be made in batches. (I will make up some dimensions for this example.) Cut two pieces of covering 1" x 10". Overlap them on the long edge by 1/4" with the adhesive sides face to face. Place on a glass sheet and use a trim iron along the overlap to join them. You now have something that is 10" long by 1.75" wide. This is the stock from which you will slice off 1/2" strips. The strips are your hinges and they are ready to install. Actually not hard to do as there are no critical steps like cutting hinge slots. Just spend a mindless evening with the radio on and your iron hot and it goes quickly. I hope this makes some sense to you.

BTW, this is originally intended to work with mating surfaces that are rounded to best give the rolling effect. But I have salvaged a plane which had a square wing TE and only a rounded aileron LE. It should work OK on the common V-bevelled aileron LE. But it is not the way to go if the aileron LE has a slant bevel. .

crashed2

My Feedback: (4)

Thanks for the help on this. Both ways sound good I like the way it shows at the link Bill gave, that looks like it might hold up better, but I think it shows on the plans the way Dave explained it. It shows 3 little strips in a few different places on the control surface connecting it to the wing and stabs. Does that method hold well? Seeing that the stabs are 3/32 slab surfaces, I would like to do it that way if it will hold.

Thanks again for the help!
Jim

Dsegal

The rolling hinges are never going to let go if ironed on well. I install them all the way across the aileron surface.

crashed2

My Feedback: (4)

Dave,
When using these hinges, do they get put on before covering so the covering might help hold them on, or after covering so they are on top of the covering?

Thanks, Jim

Rodney

Dsegal describes the way I do it most of the time. Doing this way allows you to not have any gap at all and you can leave the trailing edge of the wing flat and the leading edge of the aileron flat; i.e. butted tight against each other. I do iron on a strip of the proper color over the mating edges and lap about 1/4 inch on top and bottom before ironing on the hinge material. Apply the hinges prior to covering the wing and ailerons. I use this on 1/4 scale sized planes as well. I have used Monocote, Solartex, and Ultracote--all work equally well. I have never had a hinge failure in well over 12 years of using this type hinge, in fact my big Phaeton 90 with a Quadra 72 on it, is now over 12 years old and an esitmated 1000 plus flights is still going strong with this type of hinge.
A gentlment named Swooper put a good picture of this on http://www.flightlines.com/forum/For...ML/000053.html but I do not think it is any longer accessable. Perhaps if he sees this he would be so kind as to reissue that graphic as it was extremely good.

Dsegal

With my planes no bigger than .25 size, I have ironed the hinges on after the model was covered. But Rodney's method looks good also.

crashed2

My Feedback: (4)

Thanks guys for all your help. The roll method I think is what is supposed to be used, but I may even try the other way. Which ever way I choose at least I know now how to use the Monocote hinge method.

Thanks again, and Happy Flying!

BWooster

Another good source on Monokote hinges and control surface design is Andy Lennon's book, the name of which escapes me.

Dsegal

Having belatedly joined the digital image revolution I can now post a photo which may make the rolling hinge clearer. At the top is the hinge material composed of two strips of covering material ironed with the adhesive sides facing each other. Below this the assembled strip is cut into hinge strips. In the mockup at the bottom the hinges have been inserted, from alternate sides, and then ironed down.

bluesago

I've used both type of monocote hinges (rolling and the other type mentioned) with success. Since "everyone" uses CA hinges I'm trying them, without great success.
Why are CA hinges so much more common?

CafeenMan

CA hinges are easy to install. That's why "everyone" uses them. There are so many things wrong with them that I'm not one of the "everyone" who uses them. In fact, on my custom builds, I won't put in CA hinges unless the customer absolutely demands it and then I make it very clear I'm not going to be held responsible for any failure of any type on a control surface using CA hinges and subsequent damage.

CrazyHerb-RCU-delete

My Feedback: (2)

I wouldn't even hesitate to use monokote hinges on anthing up to a giant scale.

Here's my drawing of how I do it...

http://www.crazyherb.com/PlansandDra...ERINGHINGE.jpg

I have several designs I've used this method on .... one that has been going for two years and doesn't show any signs of wear...
My latest is the Plank 40...just using clear packing tape...

I love the gapless look and zero resistance of monokote/packing tape hinges.....all the power of the servo goes into pushing the surface...not fighting the hinge stiffness.

Good Luck!
CrazyHerb

O2man

My Feedback: (5)

Question?

What is your specific concern about the new look of RC Universe?

Kenny R

I use monocaot hinges for the ailerons , I dare say if they are put on right I beleive you would tear the wing into before you could pull the aileron off.