Re: CEF speed contest Design Discussions (2014)

pkrankow Thu Apr 09, 2015 9:23 pm

JPvelo wrote:
pkrankow wrote:OK, does a "tandem" wing aircraft fall under biplane rules? The span of the forward and aft wings are nearly the same.

Phil

Go for it!!

Sounds like fun!

Alright. I might have to. 12.5 inch wingspan sounds pretty nice!

Problem is the example I am looking at has fixed LG AND wing struts... just added drag. I could omit the struts I suppose.

Phil

modelbuilder49 Thu Apr 30, 2015 5:03 pm

JPvelo wrote:Mike,
I plan on using an external bladder secured through the spring end of a safety pin.

Greetings JPvelo! I really like your model .... it's sooooo kool! I would like to know where you got your wheels from or if you made them, just how did you do it because I'l like to acquire 3 or 4 sets for my "little birds".

Jim Carter

JPvelo Fri May 01, 2015 7:28 am

modelbuilder49 wrote:
Greetings JPvelo! I really like your model .... it's sooooo kool! I would like to know where you got your wheels from or if you made them, just how did you do it because I'l like to acquire 3 or 4 sets for my "little birds".

Jim Carter

Jim,
Thank you. I believe they are Glenn Lee racing wheels. I put the word out on Stunthanger that I was looking for them and someone came through. It's been long enough ago that I don't remember who it was.

Jim

modelbuilder49 Fri May 01, 2015 4:49 pm

Jim,
Thank you. I believe they are Glenn Lee racing wheels. I put the word out on Stunthanger that I was looking for them and someone came through. It's been long enough ago that I don't remember who it was.

Jim[/quote]Okee dokee!

Jim

getback Sat May 02, 2015 6:52 am

Google ed it http://www.planethobby.com/collections/vendors?q=glenn+lee There are other sites that have them too , mite get me some Thanks Huh...

pkrankow Sat May 02, 2015 7:25 am

getback wrote:Google ed it http://www.planethobby.com/collections/vendors?q=glenn+lee There are other sites that have them too , mite get me some Thanks

"sold out"

every return I found was also sold out.

I think adapting a hole saw to use a wire drill, or no center drill (drill press) might allow making something similar out of available plastic sheets.

roddie Mon Jun 22, 2015 9:27 pm

Been working on this for a few days. Just as my Rare Bear; I'm scaling directly from a screen-shot on my laptop.. and eyeballing to a large degree. The nice thing.. is the fuse's profile image I'm working from, is the size of the model.

CEF speed contest Design Discussions (2014) - Page 15 T33-110

CEF speed contest Design Discussions (2014) - Page 15 T33-110

Laid-up my laminated fuse.. 3mil luan-ply sides with 1/16" balsa sheet in-between.

CEF speed contest Design Discussions (2014) - Page 15 6-21-111

CEF speed contest Design Discussions (2014) - Page 15 6-22-110

roddie Tue Jun 23, 2015 5:54 pm

Before I get too far.. I have a wing-area question. Span is at the 15" mono-plane minimum. The root-chord is 4" and the tip-chord is 2" (symmetrical; root to tip). When I do the math.. this works out to the minimum 45 squares.. right?

CEF speed contest Design Discussions (2014) - Page 15 6-21-112

CEF speed contest Design Discussions (2014) - Page 15 6-21-112

ian1954 Tue Jun 23, 2015 6:32 pm

Not quite

(15 x 4) - ((7.5 x 1/2) x 4)

less the kerf produced by cutting

assuming 20 thou

(sqrt(7.5 x 7.5) + (2 x 2)) x 4 x .020

44.379033012149599050845501529

JPvelo Tue Jun 23, 2015 7:30 pm

Make some very small wing tips lol!

If you are making profile tip tanks that might add the span you need.

Jim

KariFS Tue Jun 23, 2015 11:54 pm

...or just make the cuts at the outsides of your markings, not in the middle of the line Wink

roddie Wed Jun 24, 2015 6:02 am

Thank You Ian, Jim and Kari... There's gusseting at the leading-edge's root on the full-size airplane, that will add the area I need. The wing-tip pods (which I plan to simulate) will add slightly to both; span and area too.

CEF speed contest Design Discussions (2014) - Page 15 Lockhe11

CEF speed contest Design Discussions (2014) - Page 15 Lockhe11

I'll use those tip-pods to help flight-trim this model. They will be a thin 2D profile shape. The inboard pod will allow ample positioning for a lead-out guide, and the outboard one will be of a heavier material to counter the extra weight on the inboard side. (controls/lines)

Oldenginerod Wed Jun 24, 2015 6:40 am

Roddie, did Cox make a jet engine?

Mike Mulligan Wed Jun 24, 2015 1:48 pm

Oldenginerod wrote:Roddie, did Cox make a jet engine?

In the last go-round, I did feel the need to point out that a DynaJet is, indeed, a reed valve engine!

Didn't get very far with that one...

tongue

Mike

roddie Thu Jun 25, 2015 6:14 am

Oldenginerod wrote:Roddie, did Cox make a jet engine?

No Rod.. but this wouldn't be the first jet model to be built for the speed contest.

Doug (GUS THE I.A.) built this cool A7 for the first contest.

CEF speed contest Design Discussions (2014) - Page 15 A71110

CEF speed contest Design Discussions (2014) - Page 15 A71110

I had considered an F-20 Tigershark.. but decided on the T-33 instead. There was a fan unit designed for the Tee Dee. I don't think it would work well with control-line though. It also wouldn't qualify for this "profile" event.

CEF speed contest Design Discussions (2014) - Page 15 Axiflo10

CEF speed contest Design Discussions (2014) - Page 15 Axiflo10

I think "Kress" made one too. Here's a model with a Bee powered fan unit.

CEF speed contest Design Discussions (2014) - Page 15 Lav10

modelbuilder49 Thu Jun 25, 2015 9:38 am

No Rod.. but this wouldn't be the first jet model to be built for the speed contest.
Doug (GUS THE I.A.) built this cool A7 for the first contest.
I think "Kress" made one too. Here's a model with a Bee powered fan unit.
CEF speed contest Design Discussions (2014) - Page 15 Lav10

[/quote]

Man!! Now that's jus' downright KOOL!! Very Happy

Ya' done good, real good!

roddie Thu Jun 25, 2015 7:42 pm

modelbuilder49 wrote:No Rod.. but this wouldn't be the first jet model to be built for the speed contest.
Doug (GUS THE I.A.) built this cool A7 for the first contest.
I think "Kress" made one too. Here's a model with a Bee powered fan unit.

Man!! Now that's jus' downright KOOL!! Very Happy

Ya' done good, real good![/quote]

Not mine Jim! I don't know who's model that is with the fan. I save random images that interest me. I really like it though.. because it's Cox powered! Small Cox Logo

The more I look at it.. the more it looks like a free-flight model..

rogermharris Thu Jun 25, 2015 7:47 pm

You know was doing a search yesterday and saw educated fan blades made for cox 049's

roddie Thu Jun 25, 2015 7:51 pm

rogermharris wrote:You know was doing a search yesterday and saw educated fan blades made for cox 049's

"Kress" made fan units for the Tee Dee years ago, having I believe an "RK" designation in the model#. I'll see if I can find a pic.

roddie Thu Jun 25, 2015 8:34 pm

The "Axiflow" RK-049 was a Kress fan kit that I remember seeing in magazines years ago. I found these images. I don't think it was in production very long.

CEF speed contest Design Discussions (2014) - Page 15 Kress_10

CEF speed contest Design Discussions (2014) - Page 15 Kress_10

CEF speed contest Design Discussions (2014) - Page 15 Kress_11

CEF speed contest Design Discussions (2014) - Page 15 Kress_12

CEF speed contest Design Discussions (2014) - Page 15 Kress_13

With all the high performance engine tuning that takes place on this forum.. along with some really skilled builders.. I'd love to see one of these kits utilized. Back when these kits were being made, radio gear was HEAVY.. compared to what it is now.

rogermharris Thu Jun 25, 2015 8:38 pm

Now that is cool! I would like to see it on a set of control lines

roddie Thu Jun 25, 2015 8:48 pm

rogermharris wrote:Now that is cool! I would like to see it on a set of control lines

I suppose it's possible Rog. It would have to be strictly a roundy-round model.. and have a smooth runway for take-off. There's not enough area for any kind of tight turns in a control line circle. I'd still like to see it though. The Dynajet wasn't a stunter either!

rogermharris Thu Jun 25, 2015 9:42 pm

Was trying to find video of it flying

Mike Mulligan Fri Jun 26, 2015 1:22 pm

I had one of those RK-049 fans when I was a kid. If you want to try to fly one control line you's better have a smooth lot to fly from and expect a five-lap take off run! Definately 'top gear' only!

Roddie, I'm really looking forward to seeing your T-33 take shape. Your models are always interesting, well thought out and well built. Cool subject too! I had given some thought to an F-94C for a TeeDee, but I should probably just finish what I've already started...

Post lots of pics!

Mike

roddie Fri Jun 26, 2015 5:32 pm

Mike Mulligan wrote:I had one of those RK-049 fans when I was a kid. If you want to try to fly one control line you's better have a smooth lot to fly from and expect a five-lap take off run! Definately 'top gear' only!

Roddie, I'm really looking forward to seeing your T-33 take shape. Your models are always interesting, well thought out and well built. Cool subject too! I had given some thought to an F-94C for a TeeDee, but I should probably just finish what I've already started...

Post lots of pics!

Mike

Thanks Mike! I saved a 3-view of an F-94C when gathering images for the T-33.

CEF speed contest Design Discussions (2014) - Page 15 F94c_310

I know all about the finishing what I've already started thing.. It's never too late to get back to something that was put on the back-burner.. or should I say; "after-burner" Cool

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