HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old May 05, 2006, 10:32 AM
RC 4 Life
sparks's Avatar
Fort Worth, TX USA
Joined Feb 2001
4,548 Posts
Discussion
7 ft. span 757 - my first DF project

I'm designing this model based on the lessons learned from my MD-80 design.
Its a pusher prop design so you may not have seen it.
I've learned from an A-10 design years ago that a prop placed in front of a high bypass cowl looses a huge amount of efficiency.

I've seen a 757 kit here somewhere ( looks like a 737 to me) and the sound in the flight video was enough to sell me. So. . . . . . my 757 has to be ducted fan.

The idea is to use the tooling I have to make
the wings and fuselage,
stretch the gear and add trucks,
redesign the nose and tail
and mount the motors on the wings. Same plane, different configuration.
sparks is offline Find More Posts by sparks
Last edited by sparks; Jul 07, 2006 at 08:26 AM. Reason: added current photo.
Reply With Quote
Sign up now
to remove ads between posts
Old May 05, 2006, 10:34 AM
RC 4 Life
sparks's Avatar
Fort Worth, TX USA
Joined Feb 2001
4,548 Posts
Pylon

The fan units are 90 mm. (close enough to scale for me)
Motor, Mega 22/30/3.
This should be enough since the projected weight of the model will be 6 to 7 pounds ready to fly.
I'm using light ply and balsa for the pylon construction.
Placement of the ESC is still in the air.
There is room in the pylon but behind the motor is an option too.
I'll start cutting the wing skins and ribs soon.
sparks is offline Find More Posts by sparks
Reply With Quote
Old May 05, 2006, 01:07 PM
Registered User
Larry Dudeck's Avatar
Williamsville, NY, USA
Joined Sep 2000
4,494 Posts
Terrific looking MD80, even if it is propped.

Twin EDF's make beautiful music...

This will be a "must follow" thread...
Larry Dudeck is offline Find More Posts by Larry Dudeck
Reply With Quote
Old May 05, 2006, 01:52 PM
Suspended Account
Joined Oct 2002
1,034 Posts
2 90mm fans should have more than enough thrust with the Megas to fly this jet.

Rob
NCC-1701 is offline Find More Posts by NCC-1701
Reply With Quote
Old May 05, 2006, 02:49 PM
Or am I...
Bournemouth, Dorset, UK
Joined Jan 2005
2,461 Posts
Cool. Lets see some progress!!
im-sad is offline Find More Posts by im-sad
Reply With Quote
Old May 07, 2006, 01:34 PM
RC 4 Life
sparks's Avatar
Fort Worth, TX USA
Joined Feb 2001
4,548 Posts
Wings 1

This type of wing uses the Panel Type construction and is covered in the book Building with foam.
http://home.att.net/~parkflyerplastics

The wing skin and wing cores have been cut.
It took about 1/4 sheet of blue foam to get a good set of skins.
Cutting the dihedral angles with the skins and cores assembled is the most accurate way to get job done.
After the angle cuts have been made, the cores are held together with tape so the gaps for the spar and motor support can be cut.

The bottom wing skins are then bonded together , the wing core is placed on the skin so the ribs can be laid out.

More Tuesday.
sparks is offline Find More Posts by sparks
Reply With Quote
Old May 09, 2006, 07:55 PM
RC 4 Life
sparks's Avatar
Fort Worth, TX USA
Joined Feb 2001
4,548 Posts
closeing

I've got the core all cut up and the ribs in place.
The controls cables have been ran so I'm ready to close it up.
The blue tube is going to be the conduit for the landing lights.
It shouldn't be long before I start the glass work.
sparks is offline Find More Posts by sparks
Reply With Quote
Old May 09, 2006, 10:32 PM
It's Prime Time for Slime Time
b7gwap's Avatar
Joined May 2004
1,723 Posts
This is going to be sweet by the looks of it. What livery are you leaning towards on this?
b7gwap is offline Find More Posts by b7gwap
Reply With Quote
Old May 10, 2006, 01:05 PM
Registered User
Joined Oct 2005
114 Posts
Im curious about your MD-80. Did you have a thread about this or anything I can see about it?

Im working up plans for an MD-80 myself, so you can imagine Im quite interested in yours.

Thanks!

Jason
jwalsh1 is offline Find More Posts by jwalsh1
Reply With Quote
Old May 10, 2006, 03:43 PM
RC 4 Life
sparks's Avatar
Fort Worth, TX USA
Joined Feb 2001
4,548 Posts
80 Plans

I'm afraid there's not much there but here it is.

http://www.rcgroups.com/forums/showthread.php?t=483632

I have to hold back on making posts because it will be a construction article soon.
Not knowing which images they will want to use keeps me from showing them.
However. . . . . . .I do have plans and plastic parts available.
sparks is offline Find More Posts by sparks
Reply With Quote
Old May 10, 2006, 04:21 PM
Registered User
Wade Joos's Avatar
United States, UT, Salt Lake City
Joined Aug 2002
1,230 Posts
I'm in

Put me down for a set of plans and plastic parts.
Let me know when you are ready & how much
You do amazing work

Later
Wade
Wade Joos is online now Find More Posts by Wade Joos
RCG Plus Member
Reply With Quote
Old May 11, 2006, 12:30 PM
Registered User
Joined Oct 2005
114 Posts
Quote:
Originally Posted by sparks
.........I do have plans and plastic parts available.
Yea? How can a guy get these plastic parts and plans?
jwalsh1 is offline Find More Posts by jwalsh1
Reply With Quote
Old May 11, 2006, 04:31 PM
RC 4 Life
sparks's Avatar
Fort Worth, TX USA
Joined Feb 2001
4,548 Posts
Give me a chance to figure the cost of the plastic and I'll make a post soon.
sparks is offline Find More Posts by sparks
Reply With Quote
Old May 12, 2006, 08:58 AM
Registered User
Joined Oct 2005
114 Posts
You rock.
jwalsh1 is offline Find More Posts by jwalsh1
Reply With Quote
Old May 12, 2006, 04:18 PM
RC 4 Life
sparks's Avatar
Fort Worth, TX USA
Joined Feb 2001
4,548 Posts
To avoid confusion about the 757 I have posted plans and plastic information about the MD-80 in the thread located here. . . . .
http://www.rcgroups.com/forums/showt...=2#post5466179

BTW
The wing has been glassed and I'll start on the fuselage soon.
I had to take a week off of the project to do some plastic tooling on a customers kits.
I should be able to fire up the bow next week.
sparks is offline Find More Posts by sparks
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
My first electric project jfrabat Sport Planes 57 Sep 22, 2012 03:45 PM
My first fanfold project shakysticks Foamies (Kits) 0 Jan 22, 2004 05:03 PM
wohoo my first balsa project takes to the skies! : Dandy sports someone special Parkflyers 7 Jun 02, 2003 05:56 PM
Pibros Twinn EDF-50 "My first EDF project" Appie Electric Ducted Fan Jet Talk 13 Oct 25, 2002 04:57 PM
When should I attempt my first scale project? totalboss Scale Kit/Scratch Built 3 Nov 14, 2001 02:34 PM