gkaraolides

Hi David,

Later Super Sicrolys and earlier Curares had the system you describe. Later Curares had separate spoilers recessed into the wings just in front of the flaps that were rigged to come up when the flap reached full downwards extension.

Best regards,

George

doxilia

My Feedback: (3)

Hi George,

I recall that setup too but more on the Arrow than on the Curare. Did Prettner and Matt do this in their later F3A entries?

I have to look back in Chino's thread to see if that's what he is doing...

If so, I would JB Weld some thin metal flanges around the tubes and then do the same with the flanges on the spoiler. The trick I think is to make sure one gets good adhesion after the spoilers have been finished. It will be a pain to finish them once installed unless sprayed in some careful fashion. I'd be concerned with overspray.

David.

chino_2005

Bjr 93tz: You are right, but the plans doesn´t call for any tag. Then, when I mounted the system I had same concerns about how to glue the spoilers-flaps. Now is too late to solder a plate, maybe I´ll use a good glue but who knows if it will hold them in place.<o></o>

Jim Purcha: I had to modify the upper airfoil zone to fit it properly.<o></o>

Doxilia: See the plans capture of the spoiler-flaps set up. About the servos I´ll use a single servo for the ailerons and for the spoiler-flaps, it´s too late to modify some things…<o></o>

Regards,<o></o>

Chino<o></o>

doxilia

My Feedback: (3)

Chino, George,

that's what I thought - those are the recessed flap/spoiler combo I was thinking about. No separate spoilers as on Matt's Arrow George.

I don't understand why there is any need to attach the spoilers to any torque tube, they get glued on to the flaps and extend on to the wing. Ideally in a recess. The flaps are the ones that are inserted into the torque tube. Without the flaps attached, there are ways to do this if there is no insert into the flap. You could use LG metal straps which are wrapped around the tube and then the flanges simply inserted into the flap as if it was a hinge. Provided the flanges are roughed up, epoxy should be fine when glued into the wood. For the bond to the brass tube, I'd go with JB Weld (you must have something similar in Argentina).

This design doesn't decouple the flaps and spoilers though. They move in tandem, right?

David.

chino_2005

David,<o></o>

Yes, they move in tandem.<o></o>

What´s the meaning of JBweld? I was planning to use epoxy.<o></o>

By the way, I wroke one ofmy planes yesterday and I´ve a O.S. .40 available. I´m going to build a Tiporare .40with the plans you scaled down.<o></o>

Chino<o></o>

gkaraolides

Hi David,

Prettner used them on his '77 World Championship Curare described in the RCM&E article. The earlier style are shown on the plans but the later style are clearly shown in the photos and described in the captions.

Best regards,

George

doxilia

My Feedback: (3)

George,

of course, thanks for the reminder. It's be a few years since I read that article.

Chino is not building his Curare in that fashion though, right? He's using the older flap/break combo as in the drawing shown a few posts up. I guess I was just trying to figure out with the rest of you guys how one could rig the controls to the brass work...

David.

doxilia

My Feedback: (3)

The web is your friend :

http://en.wikipedia.org/wiki/J-B_Weld

http://www.youtube.com/watch?v=A8kFwEYf7s0

It's basically steel armored epoxy as I mentioned in my first mention of it. It will bond just about anything to anything forever provided it can grab on to the part (i.e., the part has to be "rough").

Cool! So long as put a pipe on it, that's ok... [8D]

David.

chino_2005

Ok, I´ll see if I can get one like this in Argentina.

doxilia

My Feedback: (3)

Chino,

if you can't find epoxy like that in Argentina (I doubt it in this day and age), you could also use slow cure epoxy (I'd use 45 min or longer) and lace it with a good dose of milled fiberglass (not the same as micro balloons!) until it feels nice and "gritty" to the stir. It will have a similar effect to the JB Weld although it's not quite as good on metal.

If you are able to slide a thin metal flange between the brass tube and the wing TE and make some pseudo-hinges out of the metal, that would work out well. All you would need is two per flap/spoiler with two small holes in the "hinge" portion to aid in the glue gripping to both the flap wood and the metal flange - a "glue pinning" of sorts. Basically fold the metal over the rod, then flatten the two ends together once wrapped around, cut both flanges to length (~1/2"), glue the piece to the rod and the two flanges together. Then, when cured, drill the two holes through the flange portion at each end, make the cutouts in the flap and glue the flap on to the hinge with the same stuff. Regular epoxy may "slip" off metal like that, even if roughened, unless there are holes in it to produce a bridge of sorts between the upper and lower slot in the control - that's why plastic hinges like DuBro for example are drilled through.

The weak point in that setup will be the bond of the metal loop hinges around the brass rod. Make sure both metals are rough where they mate and you should be fine if you use laced epoxy with steel or fiberglass. You could even use CF if you can source that but it might be trickier. This is the FG I'm talking about:

http://www3.towerhobbies.com/cgi-bin...?&I=LXK312&P=7

And this epoxy should work:

http://www3.towerhobbies.com/cgi-bin...?&I=LXK303&P=7

And JB Weld:

http://www3.towerhobbies.com/cgi-bin...&I=LXR376&P=ML

Tower will ship to you, although it might take a little time...

David.

chino_2005

Thank you David for the info!

I usually travel to USA and can buy things from Tower. I´ve the same Great Planes epoxy but 30 minutes.<o></o>

Good idea thepseudo-hinges, maybe I´ll use something like that.<o></o>

bem

My Feedback: (1)

Hi,

Juat wanted to add that Hanno Prettner had a third variant (and the last) of the spoiler in Tournament Of Champions (TOC) 1977 where he won with his Curare. See pictures below from Model Airplane News, March and April 1978.

/Bo

gkaraolides

Hi Bo,

Great info about the third evolution of the Curare spoiler, thanks for posting it!

Even more interesting: looking at the photo of the underside of the wing, it looks like an an aileron pushrod is emerging from a slot in the wing just outboard of the spoiler - or alternatively, is attached to a servo arm or bellcrank protruding from the wing - the picture isn't clear enough to tell.

It also looks like a clevis on the end of that pushrod is attached to a particularly long aileron horn, which appears to be raked back in a manner which would provide differential aileron throw (more up than down).

This would suggest that Prettner abandoned the concentric torque rods for ailerons and flaps for his 1977 TOC Curare, and that he could even have gone to servos in the wings.

None of these features are on any plans of the Curare or the later Magic that I have (and I have several) or that I know of.

Does anyone have any additional information?

Best regards,

George

helisrme

Where may I go to get complete plans for the Curare 60? Please email me directly at southerngentle_1 at yahoo dot com. Thanks

gkaraolides

You might find the following to be a helpful start:

[link=http://www.airagestore.com/curare.html]Curare plans from MAN Plans Service (USA)[/link]

[link=http://www.myhobbystore.co.uk/product/15941/rc1323curare]Curare plans from RCM & E Plans Service (UK)[/link]

[link=http://www.vth.de/shop/warenkorb/artikel-einzelansicht/4003/2b9f911814d09f3f145411aea28f1cf6.html]Curare plans from VTH (Germany)[/link]

[link=http://www.trentonrcflyers.com/pattern/plans/Curare.zip]Curare parts outlines and plans[/link] on the [link=http://www.trentonrcflyers.com/pattern/articles-plans-instructions.htm]Trenton RC flyers Classic Pattern Articles Plans and Instructions[/link] page.

Best regards,

George

chino_2005

I didn´t know that theCurare had this type of brake.... like some antique gliders.<o></o>

Chino

bjr_93tz

Here they are "deployed".

Airbrakes certainly don't get any easier than this to install and they do a great job of slowing down and stabilising the plane. I've tried the occasional landing without them on windy days and the plane just feels too slippery, it's what you get used to I suppose. I wouldn't build a Curare without them...

Wrapping a tab around the brass torque tube with JBweld as suggested sounds a good option.

chino_2005

dchuah

My Feedback: (1)

Chino,

Didn't catch the earlier part about your canopy. Singapore Hobby still has some. I bought it not too long ago to complement the Eureka kit. And Don's replicated them.

Let me know if you want it? I'm due to be in Santiago on Nov 29th and have a few colleagues flying there sooner.

Dave

chino_2005

dave_anderson

My Feedback: (47)

Subscribed! Great work.

chino_2005

Thank you!

mobileraptor

My Feedback: (1)

I presume the front servo is controlling the speed brakes and the aft servo is controlling the alerions threw a long steel wire running down the trailing edge of the wing.

dave.windymiller

Heres my curare from a few years ago (before i repainted it). I didnt find these spoilers much use so just use flaps with no extension now.

bjr_93tz

Yep, just as per plan.

20 years later with today's cheap technology and my improved paypacket I'd ditch the concentric torque tube and rod arrangement and run 4 digital servos in the wing.....