Cox Engines Forum
You are not logged in! Please login or register! Guests are limited to posting in the "General Questions (Guest Posting Allowed)" section only. Becoming a member is fast, easy and FREE!


Log in

I forgot my password

Search
 
 

Display results as :
 


Rechercher Advanced Search

Latest topics
» Cox .020 Skycopter fuel tank replacement
by NEW222 Yesterday at 11:08 pm

» Vintage U control tether car
by Mark Boesen Yesterday at 10:32 pm

» If you thought that USPS was bad ...
by 944_Jim Yesterday at 8:53 pm

» The new W-196 arrives......finally
by crankbndr Yesterday at 8:42 pm

» Ronnie's engines
by Cribbs74 Yesterday at 8:27 pm

» Out of ideas - Help :(
by roddie Yesterday at 8:08 pm

» Cox Engine Forum Speed Contest 2018!!!
by getback Yesterday at 5:17 pm

» .010 Freeflight
by Ken Cook Yesterday at 4:55 pm

» CEF Honors All Who Served
by GallopingGhostler Yesterday at 1:16 pm

» Question re. Helldiver fuel tank
by Cox International Yesterday at 11:31 am

Cox Engine of The Month
November-2018
1/2A Nut's

"Speedy Teedy .020"



PAST WINNERS
Speed Contest 2018
CEF Traveling Engine

Win This Engine!
The Traveling Prop
Gallery


World of Aviation

Is it worth buying the parts for a 049 tee dee rather than try finding one?

Page 3 of 3 Previous  1, 2, 3

Go down

Re: Is it worth buying the parts for a 049 tee dee rather than try finding one?

Post  balogh on Wed Mar 07, 2018 12:52 am

xtal_01 wrote:Just want to keep learning ....

Kim explained why I want to use a wedge tank for U-control flight ... makes sense.

So why do I see some people using a balloon tanks?

And why / when do you the pressure port on the tee dee?

And why do some people drill / tap a pressure port in the back of the engine?  Do you then need a check valve?

Just all kinds of questions.

Mike

Mike,

I can only speak for R/C applications and about my experience, others may chime in with similar R/C and C/L advice.

The balloon tanks I use are not pressurized, I actually select a party balloon the size of which is just a bit larger than the volume of fuel I want it to carry....typically 1...2 oz for 049....09 COX engines, and smaller for the 010...020 size TeeDee-s. With a 2 oz syringe I fill up the balloon only to such a point when fuel starts to flow by itself into the engine with the plane in horizontal position, indicating that the fuel has just occupied the full volume in the balloon before it gets pressurized. Pressurization would make the mixture too rich at take-off and NV setting therefore problematic.

A balloon tank only takes 2  lines, one filler, and one supply line, no need for venting, no foaming due to engine vibration, good supply of fuel in inverted flights even without a heavy clunk, etc. The photo shows the tank of my LilRoughneck R/C bird (driven by a Killer Bee clone I assembled from parts, that I call TeeDeeReedie owing to its cylinder), removed from the tank compartment in the nose of the fuselage. I added a small plastic filter between the tank and the engine.



Or, another arrangement for the SIG Wonder R/C I built recently for TD09 engines:



Reedie and TD engines both have enough suction power to draw the fuel if the diameter of the fuel line is not too small, the distance between the tank outlet and engine fuel nipple is max, say, 10 cm or 4 inches, and the tank bottom is not more than 1 inch below the carburetor level.
avatar
balogh
Diamond Member
Diamond Member

Posts : 1976
Join date : 2011-11-06
Age : 60
Location : Budapest

View user profile

Back to top Go down

and now I know ther rest of the story!

Post  xtal_01 on Wed Mar 07, 2018 12:25 pm

Thanks for the explination! I made the bad assumption (thus I know enough to ask) that a balloon tank meant a pressurized system. Obviously not the case!

Makes more sense to me now.

Still not sure why then people use the pressure port or they tap the back of the case for pressure if it is not needed? Is this only if you use too small of line ... or drill out the carb too big (so there is little suction) ... or have the tank too far away ... or ?

Mike
avatar
xtal_01
Bronze Member
Bronze Member

Posts : 42
Join date : 2018-02-26
Age : 56
Location : Jericho, Vermont

View user profile

Back to top Go down

Re: Is it worth buying the parts for a 049 tee dee rather than try finding one?

Post  fredvon4 on Wed Mar 07, 2018 12:29 pm

For combat and speed events ( that allow pressure) one great way to get a lot of power/rpm is to run as big a venturi as possible... when you do that to many engines, they will not run on suction...so pressure supplied from crank case or Bladder is needed
avatar
fredvon4
Diamond Member
Diamond Member

Trusted Seller
Posts : 2516
Join date : 2011-08-26
Age : 63
Location : Lampasas Texas

View user profile

Back to top Go down

Again ... makes sense!

Post  xtal_01 on Wed Mar 07, 2018 12:44 pm

I love it that I no longer have to guess at answers!

Thanks for the explanation!

What did people do before the internet to find answers?

Mike
avatar
xtal_01
Bronze Member
Bronze Member

Posts : 42
Join date : 2018-02-26
Age : 56
Location : Jericho, Vermont

View user profile

Back to top Go down

Re: Is it worth buying the parts for a 049 tee dee rather than try finding one?

Post  fredvon4 on Wed Mar 07, 2018 4:13 pm

WE Tried hard to trust our friends were not BSing us...grin

Most of us read EVERY magazine we could find as did you---- and a lot was passed from dad to son or old guy to neophyte

BUT still there were many many guys who held their secrets secret....

BUT a lot of it was just us kids tinkering around and finding what did or did not work

Then there was the hobby shop guy most of the time super helpful with "you need this" to do that...OR have you thought about this new fuel or glue or whatever...Hey Fred I just got in a few of the New "whatevers" want to try one out? How I got my first Black Widow...that I though was wicked fast with a new can of Missile Mist....



avatar
fredvon4
Diamond Member
Diamond Member

Trusted Seller
Posts : 2516
Join date : 2011-08-26
Age : 63
Location : Lampasas Texas

View user profile

Back to top Go down

Re: Is it worth buying the parts for a 049 tee dee rather than try finding one?

Post  Kim on Wed Mar 07, 2018 4:25 pm

fredvon4 wrote:

BUT a lot of it was just us kids tinkering around and finding what did or did not work


THAT was the fun part !!!!
avatar
Kim
Top Poster
Top Poster

I Support My Forum

Posts : 6267
Join date : 2011-09-06
Location : South East Missouri

View user profile

Back to top Go down

Huge shout out to Kiim!!!!!!!!!

Post  xtal_01 on Fri Mar 09, 2018 7:32 pm

Just wanted to give a huge thanks to Kim!

He gave me my first Tee Dee and I just got it in the mail today.

Man this is truly a piece of beauty!

I can't wait to hear it run!!!!!!!!!!!!!!

Thanks again Kim !!!!!!!!!!!!!!!!!!!!!!!!!!!!

Mike

PS .... now can someone send some warm weather ... still snowing here in Vermont
avatar
xtal_01
Bronze Member
Bronze Member

Posts : 42
Join date : 2018-02-26
Age : 56
Location : Jericho, Vermont

View user profile

Back to top Go down

What side does the need go on?

Post  xtal_01 on Fri Mar 09, 2018 7:49 pm

I usually see pictures showing the needle sticking out to the left (if looking at the front of the engine).

However, I just saw a picture saying this is for free flight and it shows the needle sticking out of the right (again looking at the front of the engine) for u-control.

First, is this true? Does it matter?

Second, if it is true, do you "flip" the needle so that you have the black metal spring piece on top (putting the needle between the venturi and the cylinder) or do you put it in front of the venturi? And if this is true, do you use spacers so the carb does not hit the body nut?

Thanks again ...... Mike
avatar
xtal_01
Bronze Member
Bronze Member

Posts : 42
Join date : 2018-02-26
Age : 56
Location : Jericho, Vermont

View user profile

Back to top Go down

Re: Is it worth buying the parts for a 049 tee dee rather than try finding one?

Post  Mark Boesen on Fri Mar 09, 2018 10:31 pm

the needle can be flipped and/or rotated front to back or left to right, it depends on where your fuel line is coming out and if it might come in contact with ground on hard landing.
avatar
Mark Boesen
Top Poster
Top Poster

Posts : 3628
Join date : 2011-09-01
Age : 60
Location : Rockford, Il

View user profile http://groups.yahoo.com/group/049Collectors/

Back to top Go down

Re: Is it worth buying the parts for a 049 tee dee rather than try finding one?

Post  Kim on Sat Mar 10, 2018 3:30 am

xtal_01 wrote:Just wanted to give a huge thanks to Kim!

Glad to hear it made it through all the weather that's stacking up on that side of the country!

Hope it works great for you!

Kim
avatar
Kim
Top Poster
Top Poster

I Support My Forum

Posts : 6267
Join date : 2011-09-06
Location : South East Missouri

View user profile

Back to top Go down

Re: Is it worth buying the parts for a 049 tee dee rather than try finding one?

Post  Sponsored content


Sponsored content


Back to top Go down

Page 3 of 3 Previous  1, 2, 3

Back to top

- Similar topics

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