Cox Engines Forum
You are not logged in! Please login or register.

Logged in members see NO ADVERTISEMENTS!


Latest plane. Finished yesterday, maidened today Cox_ba12




Latest plane. Finished yesterday, maidened today Pixel

Log in

I forgot my password

Search
 
 

Display results as :
 


Rechercher Advanced Search

Latest topics
» Older ignition books
by lla Today at 4:17 pm

» Fox .35 Modifications
by Onelife Today at 3:54 pm

» Jim Walkers FireBee - This is going to be fun
by rsv1cox Today at 3:33 pm

» *Cox Engine of The Month* Submit your pictures! -May 2024-
by getback Today at 10:23 am

» S1 Ringmaster
by Onelife Today at 8:40 am

» Speed plane - Crispy but not too crispy
by rsv1cox Today at 7:54 am

» O&R 23 & Brown Jr
by getback Today at 7:47 am

» Introducing our Cox .049 TD Engines
by MauricioB Today at 2:31 am

» Jim Walker Firebaby
by rdw777 Yesterday at 4:16 pm

» Hemostat clamp/smooth-jaws
by roddie Yesterday at 3:48 pm

» Black Widow Run time
by Ken Cook Yesterday at 3:44 pm

» 1:64 scale Diecast (Hot Wheels)
by roddie Yesterday at 3:33 pm

Cox Engine of The Month
April-2024
OVERLORD's

"Kress ducted fan with new Cox Conquest 15 RC"



PAST WINNERS
CEF Traveling Engine

Win This Engine!
Gallery


Latest plane. Finished yesterday, maidened today Empty
Live on Patrol


Latest plane. Finished yesterday, maidened today

Go down

Latest plane. Finished yesterday, maidened today Empty Latest plane. Finished yesterday, maidened today

Post  batjac Tue Sep 03, 2013 2:43 am

So, since the Delta Park fly-in was today, I needed a new plane to fly there.  I decided I wanted to do a PeeWee powered plane, so I dug around for designs for the .020.  I settled on the Little Gem from the June 1961 issue of Model Airplane News.  It had a few unique things about it that made it my choice for the next building project:

1) It was old Vintage.
2) It had an offset fuselage.
3) It had a diamond airfoil.
4) It wouldn't take up too much of my on hand balsa.
5) I could fly it all day on two ounces of fuel.


As usual, I forgot to take a picture of the "kit" I cut out from my wood supply.  I was almost finished with the wing before I remembered to get the camera:
Latest plane. Finished yesterday, maidened today DSCN0623_zps590c1094


And gluing on the leading and trailing sheet.  Diamond airfoils were a fad for a while back then.  I don't know that they had any flying advantage, but I wanted to try building one as I figured it'd be easy to build the wing flat on the board with the straight angles, instead of a curved airfoil that would need a jig to build.
Latest plane. Finished yesterday, maidened today DSCN0625_zps06cc5ba0


The wing, minus the center section, and the rest of the "kit".
Latest plane. Finished yesterday, maidened today DSCN0627_zps378d6155


Mounting the bellcrank.  The plans call for an aluminum sheet bellcrank, but I find that it's easier for me to just cut one out of 1/16 ply and put a layer of thin CA over it to harden it.  I've done this with two other planes, as it's cheaper for me to use my scrap ply than the $2.00 Goldberg bellcranks from Cox International (sorry Bernie).  I just trade an hour of fabrication for the $2.00 for the plastic ones.  I guess my time is pretty cheap.  Time will tell if they last.
Latest plane. Finished yesterday, maidened today DSCN0628_zpsc42fc525


The parts covered and ready for final assembly.
Latest plane. Finished yesterday, maidened today DSCN0630_zpsa9febef9


And assembled, waiting for the motor.  I had to test run the motor and get it tweaked in before mounting.
Latest plane. Finished yesterday, maidened today DSCN0632_zps0101f00f


With the motor mounted.  This is my $6.00 eBay PeeWee.
Latest plane. Finished yesterday, maidened today DSCN0638_zps2c07c050


The plane ready to fly weighs 2.25 ounces, or for our friends across the pond, 64 grams.
Latest plane. Finished yesterday, maidened today DSCN0636_zps0c1436cd
Latest plane. Finished yesterday, maidened today DSCN0637_zps1d34f606

At first, I was a little worried that it'd be really squirrely, since the bellcrank holes are only about 1 1/8" apart.  But, it was okay after I got a toss from Duke's eldest son.  But, on 18' lines, this thing was FAST! I tried counting, and it seemed like I was doing about 2.5 second laps.  this was with the standard 4.5x2 Cox prop.  The MAN article says to use the 3 bladed prop if using a stooge for great verticals and for speed.  I don't even want to know how fast this thing would be on the 3 bladed prop.

The Vintage Mark
batjac
batjac
Diamond Member
Diamond Member

2022 Supporter

2023 Supporter

Posts : 2336
Join date : 2013-05-22
Age : 61
Location : Broken Arrow, OK, USA

Back to top Go down

Latest plane. Finished yesterday, maidened today Empty Re: Latest plane. Finished yesterday, maidened today

Post  Cribbs74 Tue Sep 03, 2013 8:16 am

Mark,

I built one of those too for my son. I didn't offset the wing and I chose to sheet the entire wing. It flies ok.

I too built a bellcrank out of ply. I am using the 3 blade prop.

Your's looks great! Here is a pic of mine.

Ron

Latest plane. Finished yesterday, maidened today 6Mcz87Ol
Cribbs74
Cribbs74
Moderator

2022 Supporter

2023 Supporter

2024 Supporter

Posts : 11895
Join date : 2011-10-24
Age : 50
Location : Tuttle, OK

Back to top Go down

Latest plane. Finished yesterday, maidened today Empty Re: Latest plane. Finished yesterday, maidened today

Post  duke.johnson Tue Sep 03, 2013 8:52 am

Mark let my son fly this little plane yesterday and now wants to build one. He loved it!
duke.johnson
duke.johnson
Diamond Member
Diamond Member

Posts : 1734
Join date : 2012-11-05
Age : 52
Location : Rochester, Washington

Back to top Go down

Latest plane. Finished yesterday, maidened today Empty Re: Latest plane. Finished yesterday, maidened today

Post  andrew Tue Sep 03, 2013 8:56 am

The Lil' Gem was my first scratch-build; the full size plans were a pullout in MAN, circa 1961.  I didn't have a .020, but did have an .049 from a COX plastic Cub, so I scaled it up a little larger.  I don't remember if I built it with the offset or not.

Latest plane. Finished yesterday, maidened today Little10
andrew
andrew
Diamond Member
Diamond Member

Posts : 1813
Join date : 2011-08-11
Age : 76
Location : Western Kentucky

http://web2.murraystate.edu/andy.batts/ps/POWERSUPPLY.HTM

Back to top Go down

Latest plane. Finished yesterday, maidened today Empty Re: Latest plane. Finished yesterday, maidened today

Post  batjac Thu Sep 19, 2013 5:55 pm

Cribbs74 wrote:Mark,

I built one of those too for my son. I didn't offset the wing and I chose to sheet the entire wing. It flies ok.

I too built a bellcrank out of ply. I am using the 3 blade prop.

Your's looks great! Here is a pic of mine.

Ron

Latest plane. Finished yesterday, maidened today 6Mcz87Ol
Ron, that looks great! I was thinking about doing another one without the offset like you did. I have another fuse cut out, so I could just do another wing and tail set. I was thinking of making the wing tips and tail tip diamond shaped also, just using a wing rib cut in half to give the half-diamond shape. And maybe making the snout a little more pointed also.

The Pointed Mark
batjac
batjac
Diamond Member
Diamond Member

2022 Supporter

2023 Supporter

Posts : 2336
Join date : 2013-05-22
Age : 61
Location : Broken Arrow, OK, USA

Back to top Go down

Latest plane. Finished yesterday, maidened today Empty Re: Latest plane. Finished yesterday, maidened today

Post  Cribbs74 Thu Sep 19, 2013 8:55 pm

Mark,

I would consider adding some offset. As designed it has no tip weight or rudder offset. While rudder offset is not really needed without engine offset I feel it would go slack in anything besides a large flowing inside loop. Not to mention it may have a tendancy to roll in without the tip weight.

Just a thought, I haven't given mine enough of a workout to get a true feel of things. For some reason my controls are stiff and need to be looked at. It was my second or third scratchbuild and I did things I would not even consider doing now.

Ron

The Jr. Falcon decals were for my then 6yr old son. He wanted something on the wing and I had those laying around.
Cribbs74
Cribbs74
Moderator

2022 Supporter

2023 Supporter

2024 Supporter

Posts : 11895
Join date : 2011-10-24
Age : 50
Location : Tuttle, OK

Back to top Go down

Latest plane. Finished yesterday, maidened today Empty Re: Latest plane. Finished yesterday, maidened today

Post  Sponsored content


Sponsored content


Back to top Go down

Back to top

- Similar topics

 
Permissions in this forum:
You cannot reply to topics in this forum