Espritmodel.com Telemetry Radio
Reply
Thread Tools
Old Jan 05, 2013, 12:06 PM
Pencil grip
hoffboy's Avatar
Olympia, WA
Joined Feb 2008
1,223 Posts
Build Log
"TV" Sparky (Aeromodeler 1951) - Britplan Build Off January 2013 to June 2013

Placeholder in the hope that my 10-year-old son and I can bang this out by the deadline.
hoffboy is offline Find More Posts by hoffboy
Last edited by hoffboy; Jan 06, 2013 at 12:45 AM. Reason: Added "TV" to title
Reply With Quote
Sign up now
to remove ads between posts
Old Jan 05, 2013, 09:29 PM
First to go over 106K feet
Crist Rigotti's Avatar
USA, IA, North Liberty
Joined Mar 2008
2,479 Posts
Hey, September 1951 was when I was born! I'll be following your progress. It would be neat to build a design as old as I am!
Crist Rigotti is offline Find More Posts by Crist Rigotti
Reply With Quote
Old Jan 05, 2013, 10:46 PM
Pencil grip
hoffboy's Avatar
Olympia, WA
Joined Feb 2008
1,223 Posts
Quote:
Originally Posted by Crist Rigotti View Post
Hey, September 1951 was when I was born! I'll be following your progress. It would be neat to build a design as old as I am!
Owen (my boy) and I have been reviewing the plans, discussing RC mods. Rudder will be interesting. I've been thinking of how to integrate a tail wheel while keeping the keel. Hoping to hide the rudder and elevator horns in the fuse.
hoffboy is offline Find More Posts by hoffboy
Reply With Quote
Old Jan 06, 2013, 01:55 AM
I like real wooden aeroplanes!
Sundancer's Avatar
South-west France
Joined Sep 2007
4,521 Posts
This one was on my "possibles" list too, I'll be interested to watch your progress
Sundancer is offline Find More Posts by Sundancer
RCG Plus Member
Old Jan 06, 2013, 05:20 AM
Registered User
United Kingdom, England, Richmond
Joined Apr 2011
75 Posts
Hi hoffboy your photo of a Sparky in your post is mine! It first flew in 2008 and is still giving good service. It really is a good fun vintage R/C plane and does amazing rolls with the rudder. I kept the original rudder and added elevators, power is a Scorpion 2215-18. If you build it you will not be disappointed.
Alan
edit: I have just looked at your plan which looks like a cleaned up/redrawn version. I notice it states the span as 40 inches, the original span was 48 inches - is this an error or are you going to scale it down?
ukengineman is offline Find More Posts by ukengineman
Last edited by ukengineman; Jan 06, 2013 at 05:25 AM.
Reply With Quote
Old Jan 06, 2013, 06:28 AM
I like real wooden aeroplanes!
Sundancer's Avatar
South-west France
Joined Sep 2007
4,521 Posts
Quote:
Originally Posted by ukengineman View Post
Hi hoffboy your photo of a Sparky in your post is mine! It first flew in 2008 and is still giving good service. It really is a good fun vintage R/C plane and does amazing rolls with the rudder. I kept the original rudder and added elevators, power is a Scorpion 2215-18. If you build it you will not be disappointed.
Alan
edit: I have just looked at your plan which looks like a cleaned up/redrawn version. I notice it states the span as 40 inches, the original span was 48 inches - is this an error or are you going to scale it down?
Oh yes, you are absolutely right, I hadn't noticed that when I looked at Hoffboys plan, the original was definitely 48 inches. This plan is Hogal's CAD re-draw, so maybe was deliberately scaled down? Here is the original plan. I'm sure it would work OK at the scaled down span.
Sundancer is offline Find More Posts by Sundancer
RCG Plus Member
Old Jan 06, 2013, 09:16 AM
Pencil grip
hoffboy's Avatar
Olympia, WA
Joined Feb 2008
1,223 Posts
Quote:
Originally Posted by ukengineman View Post
Hi hoffboy your photo of a Sparky in your post is mine! It first flew in 2008 and is still giving good service. It really is a good fun vintage R/C plane and does amazing rolls with the rudder. I kept the original rudder and added elevators, power is a Scorpion 2215-18. If you build it you will not be disappointed.
Alan
edit: I have just looked at your plan which looks like a cleaned up/redrawn version. I notice it states the span as 40 inches, the original span was 48 inches - is this an error or are you going to scale it down?
I noticed that size discrepancy as well. The CAD plans printed at 48", so it's an error on the plan. Did you go with the lifting elevator, or a slab? Since we'll have discrete throttle control, and a functioning elevator, I lean toward a slab. Considering enlarging the rudder by moving the hing line forward so we can run the pivot down through the keel and pick up a tail wheel. But that might be complicating things unnecessarily. Just thinking about ground handling.

Love your Sparky! (Your photos are what inspired this build, in fact.)
hoffboy is offline Find More Posts by hoffboy
Reply With Quote
Old Jan 06, 2013, 09:21 AM
Pencil grip
hoffboy's Avatar
Olympia, WA
Joined Feb 2008
1,223 Posts
Quote:
Originally Posted by Sundancer View Post
Here is the original plan. I'm sure it would work OK at the scaled down span.
Oh MUCH cleaner than my copy of the original plan and article. THANKS! I can see why Hogal thought it was 40" as that bit at the top is a tad blurry. I agree that scaled down would have probably worked fine, but I'm glad the CAD version printed at 48".
hoffboy is offline Find More Posts by hoffboy
Reply With Quote
Old Jan 06, 2013, 04:14 PM
Registered User
Canada, ON, Hamilton
Joined Oct 2005
2,469 Posts
Matt, you caught me off guard with the “Sparky”.
The Comet Sparky was what first came to mind, since I built two when I didn’t know how!
I like the article that mentions the various “set ups” tried, and the lifting tail using two degrees of negative and the engine requiring no down thrust.
On my little Brigidier (on my blog), I used a lifting tail but set it just the opposite with about two degrees positive and still used down thrust.
Looking forward to your interesting build. Good luck.
John
JohnAV8R is offline Find More Posts by JohnAV8R
Last edited by JohnAV8R; Jan 06, 2013 at 04:17 PM. Reason: lifting
Reply With Quote
Old Jan 06, 2013, 06:16 PM
Registered User
United Kingdom, England, Richmond
Joined Apr 2011
75 Posts
Quote:
Originally Posted by hoffboy View Post
I noticed that size discrepancy as well. The CAD plans printed at 48", so it's an error on the plan. Did you go with the lifting elevator, or a slab? Since we'll have discrete throttle control, and a functioning elevator, I lean toward a slab. Considering enlarging the rudder by moving the hing line forward so we can run the pivot down through the keel and pick up a tail wheel. But that might be complicating things unnecessarily. Just thinking about ground handling.

Love your Sparky! (Your photos are what inspired this build, in fact.)
I kept the airfoil tailplane exactly as the plan, only mod is the addition of small elevators - about 3/4 inch but I can measure and confirm. The original article explains the importance of the lifting tail. Rudder is as per plan. The forward undercarriage does lead to the occasional ground loop but I kept as per plan as I think it is part of the plane's character. I made one mod to the wing, I sheeted the underside from the LE to the spar as per topside, makes me feel more secure when I pull a loop.
Alan
ukengineman is offline Find More Posts by ukengineman
Reply With Quote
Old Jan 07, 2013, 02:42 AM
I like real wooden aeroplanes!
Sundancer's Avatar
South-west France
Joined Sep 2007
4,521 Posts
Quote:
Originally Posted by hoffboy View Post
I noticed that size discrepancy as well. The CAD plans printed at 48", so it's an error on the plan. Did you go with the lifting elevator, or a slab? Since we'll have discrete throttle control, and a functioning elevator, I lean toward a slab. Considering enlarging the rudder by moving the hing line forward so we can run the pivot down through the keel and pick up a tail wheel. But that might be complicating things unnecessarily. Just thinking about ground handling.

Love your Sparky! (Your photos are what inspired this build, in fact.)
I'd be inclined to keep the tailplane "as per"; if you did change to a flat plate I would expect that you would need to move the CG forward a bit. Sheeting the bottom lwing leading edge as ukengineman says is a worthwhile mod, but would only attain maximum effectiveness if you also web the spars with 1/16" balsa (grain vertical) for at least the inner 1/3 - 1/2 span to produce a full "D" box, probably well worth doing though.
Sundancer is offline Find More Posts by Sundancer
RCG Plus Member
Old Feb 11, 2013, 11:25 AM
Pencil grip
hoffboy's Avatar
Olympia, WA
Joined Feb 2008
1,223 Posts
Got the fuselage framed up, but it's looking like we won't have the time to continue working on this, so pausing for now. We'll get back to it one day though. Too sweet of a model to not complete.
hoffboy is offline Find More Posts by hoffboy
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Build Log Dart Kitten - Britplan Build Off January 2013 to June 2013 Colonel Blink Vintage & Old-Timer Designs 404 Mar 09, 2014 11:16 AM
Contest "Britplan" Build Off - 1st January 2013 to 30th June 2013 Now 22 Finished Models! Sundancer Vintage & Old-Timer Designs 257 Jul 16, 2013 12:23 PM
Discussion Cyril Shaw "Envoy" - Britplan Build Off January 2013 to June 2013 cpmcgraw Vintage & Old-Timer Designs 280 Jun 26, 2013 01:35 AM
Discussion Auster-Britplan Build-Off Jan 2013- Jun 2013 mrdj Vintage & Old-Timer Designs 6 Apr 02, 2013 06:02 AM
Discussion K. Edgerton "King Harry" BritPlan Build off January 2013 - June 2013 Doncrashum Vintage & Old-Timer Designs 4 Jan 14, 2013 05:30 PM