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Author Topic: Brodak Cardinal Profile LE Bluntness  (Read 879 times)

Offline Peter in Fairfax, VA

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Brodak Cardinal Profile LE Bluntness
« on: June 10, 2022, 10:39:55 AM »
Does the Brodak Cardinal profile kit LE consist of a 3/8" square balsa stick with 1/16" balsa sheeting?  If so, does the plane benefit from making the LE blunt?

thanks,

Peter

Online Ken Culbertson

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Re: Brodak Cardinal Profile LE Bluntness
« Reply #1 on: June 10, 2022, 11:28:24 AM »
Does the Brodak Cardinal profile kit LE consist of a 3/8" square balsa stick with 1/16" balsa sheeting?  If so, does the plane benefit from making the LE blunt?

thanks,

Peter
I built this profile from a Cardinal rib set from Brodak.  I used a 3/8" LE and rounded it to the shape in the picture.  Wish I had taken more pictures.  Exceptionally good flying plane.  The LE shape I chose was more parabolic than blunt.  Hope this helps you decide but I would not make it sharp.  FYI I flew it on an OS46FX which was too much so I downgraded to an 46LA.  It was scheduled for electric conversion when I lost it in a fire.

Ken
AMA 15382
If it is not broke you are not trying hard enough.
USAF 1968-1974 TAC

Offline Brett Buck

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Re: Brodak Cardinal Profile LE Bluntness
« Reply #2 on: June 10, 2022, 11:31:45 AM »
Does the Brodak Cardinal profile kit LE consist of a 3/8" square balsa stick with 1/16" balsa sheeting?  If so, does the plane benefit from making the LE blunt?

  I forget how it is constructed, but I would round it off the extent possible, because there can be no conceivable benefit from making it sharp.  But the big and more important change is to remove a large amount of flap area, like 1/2" off each trailing edge.

      Brett

Offline Leonard Bourel

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Re: Brodak Cardinal Profile LE Bluntness
« Reply #3 on: June 10, 2022, 01:32:23 PM »
I now have a Brodak Cardinal that is 14 years old and still flies great with the original la46 I also agree with Brett I took about a half inch off the TE of each flap IT flew way better especially on windy days Before it was a real hand full also mine needed 1 OZ of tail weight to get the CG Close I pancaked it once in the early years when the weight fell off and I did not notice at a contest . Best Len

Offline Brett Buck

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Re: Brodak Cardinal Profile LE Bluntness
« Reply #4 on: June 10, 2022, 02:06:24 PM »
I now have a Brodak Cardinal that is 14 years old and still flies great with the original la46 I also agree with Brett I took about a half inch off the TE of each flap IT flew way better especially on windy days Before it was a real hand full also mine needed 1 OZ of tail weight to get the CG Close I pancaked it once in the early years when the weight fell off and I did not notice at a contest . Best Len

  Yes, the control loads become absurdly excessive even in pretty light conditions. We (Ted and I) both flew Paul Ferrell's airplane shortly before the 2006 NATs and it was having problems with the Netzeband Wall even in 5 mph winds. Cut of some flap (3/4" in this case), kids is the Senior National Champion two weeks later.

    Brett

Offline Air Ministry .

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Re: Brodak Cardinal Profile LE Bluntness
« Reply #5 on: June 14, 2022, 10:31:11 PM »


Quote
Flap width at root: 2 7/8 inches. At tip, 1 3/4 inches.

After we flew the ARF for a while, the factory sent me a wing for the ARC version, which I still have. Tony stated that it was identical to the ARF but of course, not covered. The photo shows the shape of the leading edge, as traced from the ARC prototype wing. Note that it is not sharp.

Bob Z.


Purloined ! .

======================================================================================================================================
Scribble or ready ledge wadeius ! The front ff the Sq / Diamond is what used to be NORMAL . But past say 1/16 down in front of the top of the daimond , with increased radius , just use ' finishing paper ' .
On a block or stick , of course . Showns 1/4 Sq with 1/16 sheeting .



Online Brent Williams

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    • Fancher Handles - Presented by Brent Williams
Re: Brodak Cardinal Profile LE Bluntness
« Reply #6 on: June 14, 2022, 11:31:50 PM »
Here's a cropped view from the Brodak plans for the Cardinal. 
I highlighted the wing for easier viewing.
Laser-cut, "Ted Fancher Precision-Pro" Hard Point Handle Kits are available again.  PM for info.
https://stunthanger.com/smf/brent-williams'-fancher-handles-and-cl-parts/ted-fancher's-precision-pro-handle-kit-by-brent-williams-information/

Offline Peter in Fairfax, VA

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Re: Brodak Cardinal Profile LE Bluntness
« Reply #7 on: June 15, 2022, 06:35:46 AM »
Brent,

Thanks for the plans.  LE measures 1/4" square from the plans.

Peter

Offline Motorman

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Re: Brodak Cardinal Profile LE Bluntness
« Reply #8 on: June 15, 2022, 07:15:01 AM »
Just be careful when you round it off that you leave enough leading edge sheeting for adhesion. I've sanded through and had to back fill with some 1/16 x 1/8 strips.

Motorman 8)

Online Ken Culbertson

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Re: Brodak Cardinal Profile LE Bluntness
« Reply #9 on: June 15, 2022, 08:56:44 AM »
Just be careful when you round it off that you leave enough leading edge sheeting for adhesion. I've sanded through and had to back fill with some 1/16 x 1/8 strips.

Motorman 8)
If you are building from plans you might consider using a 5/8" LE and butt joining the LE sheeting.  I did mine that way and it made rounding the LE much simpler.  I have always had trouble getting a smooth LE when I am having to taper the sheeting much.  Probably a character flaw.

Ken
AMA 15382
If it is not broke you are not trying hard enough.
USAF 1968-1974 TAC


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