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Nov 14, 2010, 02:36 PM
Retired CAD guy
birdofplay's Avatar
WOW ! thats nearly 10' - aka a BIG Foamy !
Even 8' would be impressive.

You must be thinking PINK ! :-)

I was thinking something a bit more Park sized and transportable.
I might try ~ 60" since the wing is relatively narrow.
See early CAD screen grab below.

I will also look at how efficiently parts will fit on standard size depron
and make certain adjustments to that end.

djacob1: thanks for the pdfs !

I'm thinking that we'll need either balsa or Lite ply rib to HANG the Slats and flaperons from too.

More L8r

Bob
Last edited by birdofplay; Nov 14, 2010 at 02:48 PM.
Nov 14, 2010, 03:49 PM
Yes, "that" Karl...
karl k's Avatar
Quote:
Originally Posted by birdofplay
WOW ! thats nearly 10' - aka a BIG Foamy !
Even 8' would be impressive.

You must be thinking PINK ! :-)

I was thinking something a bit more Park sized and transportable.
I might try ~ 60" since the wing is relatively narrow.
See early CAD screen grab below.

I will also look at how efficiently parts will fit on standard size depron
and make certain adjustments to that end.

djacob1: thanks for the pdfs !

I'm thinking that we'll need either balsa or Lite ply rib to HANG the Slats and flaperons from too.

More L8r

Bob
I am kind of a sucker for the big planes.

I'm thinking 1/2" pink for the fuse and thicker pink for the wing with a couple spars from either 1x3 or plywood. Probably ply for the dimensional stability.

The problem with it being so big is the length of the fuse. I'm thinking that the tail could be made to be removable with 8 to 10 1/4-20 nylon bolts holding it on. Would just need to connect a few servo leads when it's assembled.

A side note as I'm thinking of the power system; Has anyone fuel proofed a foam plane before?
Nov 14, 2010, 04:46 PM
Retired CAD guy
birdofplay's Avatar
I do know whatcha mean :>}}}
I also do Aero Towing - Scale gliders of 3, 4, 5 meter size
towed up by 80, 100, 150 cc Monster tugs !

But about the 750 work:

I have done some flat CAD work to come up with general outlines
for a bird with 60" span. A mixture of Foam and Balsa and or Ply.

But, I Know I have to do a 3D work up at this size to check the Fit
and to develop some of the Curved parts.

I'm thinking Ply ribs with a foam rib on either side to glue toe foam covering down on.
The ply ribs will have extension for the Flap pivots and the Slat mounting.
Trying to stay as "Foamy" as possible I'm planning on using a shaped piece of
6mm Depron as the Slats.

If "see thru" windows are used then some ply inside the foam sides will be necessary
to hang the wings.

I'm also thinking about the Motor.
Either a Torquey Big Low-KV outrunner or a gear boxed Inrunner with a Big 3 blade prop !
Probably the former would be more efficient.

ON THE OTHER HAND, while I'm doing 3D I might Go crazy and
yeild to an urge to do a slot-locked ply construction altogether.

hmmmm????


See the tentative layout below
Last edited by birdofplay; Nov 14, 2010 at 04:54 PM.
Nov 14, 2010, 08:36 PM
Retired CAD guy
birdofplay's Avatar
Not done by a far piece but 'm getting there !
Nov 14, 2010, 11:08 PM
Retired CAD guy
birdofplay's Avatar
LATEST UPDATE !

Showing the Foam Ply rib sandwich

Covering over the ribs and Horner tips

Bottom view showing Slats and flaperons
Nov 15, 2010, 02:13 AM
Yes, "that" Karl...
karl k's Avatar
You'll have this built before I have all the materials!!!
Nov 15, 2010, 10:42 AM
Retired CAD guy
birdofplay's Avatar
Oh there is still a bunch to do to get the FRONT END looking better.
and the Wing connection and fairing to Fuse area is "messy" at best right now.
And with all those parts it might be getting heavy.

Foamy construction LIKE's lightness and therefore smallness.
I've found that scaling up usually is disappointing. IMHO
For instance a fairly Zippy little foamy will end up being a SLOMOTION bird
when scaled to beyond 125% .
I did a 150% Harpy which is a BLAST to fly.
The Large one was Slow, Magnificent, Majestic but not a Blast anymore !
It's just not a foamy any more its a BIG plane made out of foam.

I built a largeish Moni ( ~8') from foam once. It flew but it looked like a foamy.
For all the work it could have built from Balsa and looked much better. IMHO

So today I'm going back into CAD and work towards a more precise parts set.
And see what can be done about the Wing to Fuse connection.
Nov 15, 2010, 12:16 PM
Registered User
Broken Bottle's Avatar
Wow, Birdofplay, you're doing a great job, and a fast one, with the CAD model.
I remember someone building a huge(like half scale big) pink foam bird. I don't know if she ever got air borne but she looked great and I think the builder said it came out pretty light for how big it was.

Maybe I missed it but have you started looking at motors yet? I know it's better when you know how big the AUW range is but with this much plane, I think it might be worth the effort to start looking at them now. I know that once the weight gets beyond a point, finding motors gets freakin' hard.
Nov 15, 2010, 01:02 PM
Yes, "that" Karl...
karl k's Avatar
Power system isn't a concern. I've got the power system from my 106" Husky that suffered an ESC failure.

5335 axi and a 22x12WE prop on 12s2p a123 puts out 4500 watts

I don't think I'll need that much power. I have a few motors from 1kw to 5kw laying around.
Nov 15, 2010, 01:05 PM
Yes, "that" Karl...
karl k's Avatar
Quote:
Originally Posted by birdofplay
Foamy construction LIKE's lightness and therefore smallness.
I've found that scaling up usually is disappointing. IMHO
For instance a fairly Zippy little foamy will end up being a SLOMOTION bird
when scaled to beyond 125% .
I did a 150% Harpy which is a BLAST to fly.
The Large one was Slow, Magnificent, Majestic but not a Blast anymore !
It's just not a foamy any more its a BIG plane made out of foam.

I built a largeish Moni ( ~8') from foam once. It flew but it looked like a foamy.
For all the work it could have built from Balsa and looked much better. IMHO
I'm hoping for a BIG plane that floats just like the real thing.

As for the looks, I'm thinking it will get fiberglassed and painted once it's done.
Nov 15, 2010, 08:18 PM
Retired CAD guy
birdofplay's Avatar
Well I spent the FREE part of the day doing more design work on the 60" Foamy version.
However, most of that can be used on a large version IMHO.
I think a larger one in the Styple of the Espirit models stuff will work.
Like thier PC6 porter http://www.espritmodel.com/index.asp...OD&ProdID=2870

The whole Nose section is still vexing me, at least in CAD.
I think I could "just build it" without having to "model it" in 3D .

It would be nice if someone knew of a Cowel that would work.

I have 3 1/2 ea. Depron Cutting sheets and 1 ea. of 1/32 ply.
I decided 1/32 ply was sufficient for a foamy.
The fuse Sides get a small 1/23 reinforcement around the Side windows
for Wing attach and support.

I plan to "sheet" the wings in 3mm depron.

I think a piece balsa TE stock will work for the Flaperons.

Plus some 1/4 sq balsa and CF tubing in the wings.

Hey I see Burnaby is only about 365 miles form The Mission BC Aero Tow Site !
C U There next Summer !
Nov 15, 2010, 08:41 PM
RC Adddict
Wilfor's Avatar
burnaby isnt that far away from mission ? Much Much closer then that So your coming to BC next summer hmmm .. Got room for some cut up foam
Nov 15, 2010, 11:01 PM
Yes, "that" Karl...
karl k's Avatar
Quote:
Originally Posted by Wilfor
burnaby isnt that far away from mission ?
Must not be.

I work with someone who lives in Mission and drives in to Surrey and Richmond every day for work.
Nov 15, 2010, 11:05 PM
Yes, "that" Karl...
karl k's Avatar
Quote:
Originally Posted by birdofplay
Well I spent the FREE part of the day doing more design work on the 60" Foamy version.
However, most of that can be used on a large version IMHO.
I think a larger one in the Styple of the Espirit models stuff will work.
Like thier PC6 porter http://www.espritmodel.com/index.asp...OD&ProdID=2870

The whole Nose section is still vexing me, at least in CAD.
I think I could "just build it" without having to "model it" in 3D .

It would be nice if someone knew of a Cowel that would work.

I have 3 1/2 ea. Depron Cutting sheets and 1 ea. of 1/32 ply.
I decided 1/32 ply was sufficient for a foamy.
The fuse Sides get a small 1/23 reinforcement around the Side windows
for Wing attach and support.

I plan to "sheet" the wings in 3mm depron.

I think a piece balsa TE stock will work for the Flaperons.

Plus some 1/4 sq balsa and CF tubing in the wings.

Hey I see Burnaby is only about 365 miles form The Mission BC Aero Tow Site !
C U There next Summer !
I used to have one of those PC6's from EStar models.
Built by Martin Hunter if my memory serves.
Should have never sold it.

I think for the cowl on the big guy, I'll just build a frame and some foam ribs and sheet with FFF. Maybe just carve it out of a huge block of glued together pink foam...


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