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"Cox Tee Dee .010"



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First time benching

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Help! Re: First time benching

Post  PlaidHatter on Sun Jul 19, 2015 7:12 pm

Ok, three times for about how long? Til the fuel is spent?
Is this amount of heat normal? Wouldn't this damage or warp any of the planes parts that are in close proximity?
Doing something like this after 5 seconds of running seems extreme to me.
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Help! Re: First time benching

Post  Cribbs74 on Sun Jul 19, 2015 7:48 pm

Ok,

So, two things could have happened. You could have had some crap in the system and as it sucked it through it started to run better.... Possible

Or, you have an air leak... Likely

Gasket to crankcase, venturi to tank, backplate and/mounting screws.

Do you have access to a syringe?

you can close the needle valve, plug a vent and pump air into the tank to find an air leak.

It's an air cooled engine, yes they get hot.

Did you balance the propeller?
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Help! Re: First time benching

Post  1/2A Nut on Sun Jul 19, 2015 7:52 pm

Remember your prop is too small APC 4.2 x 2  it is going to spin up way too fast so you have to keep it running rich till you get the right prop or you will destroy the ball socket and may break or stretch the piston rod if you allow it to rev too high. Use a C clamp to hold the engine test stand down so you don't cause anymore harm to yourself.

As the engine heats up it will cause the present needle setting to appear to go leaner.
Another thing the engine may be new and is breaking in as the part begin to seat and smooth up it will pickup rpm.
Also the reed valve could be degummed as it warmed up and is performing better seating and unseating with ease.
Your stand material is not ideal for an IC engine vibrations and can cause cracks. Ok for display purposes.
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Post  cox24711 on Sun Jul 19, 2015 9:42 pm

really that prop is tiny
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Help! Re: First time benching

Post  Oldenginerod on Sun Jul 19, 2015 10:08 pm

Oldenginerod wrote:
If the engine is new and unrun, run it slow and rich for about a minute and then stop it to allow it to cool down.  Do this 3 or 4 times because it helps to temper the metal and relieve stress.  An unbroken engine can wear out really quickly but the same engine that has been correctly "heat cycled" will last a long long time.  Having said that, you're usually pretty safe with a Cox because they're very accurately made and don't seem to need as much break-in as other engines.

Rod.

As said previously. Screwing the needle out makes it richer and slows it down. It also makes it run cooler. If it starts to take off in the revs just unscrew the needle a bit more to slow it down. I recall that you mentioned the adaptors for the prop weren't right, so I suspect he vibration is mainly caused by the prop being off-centre. Also, if the prop came with adaptors, it sounds like one for an electric motor, which will not be strong enough for the Golden Bee and may fracture.

Rod.
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Help! Re: First time benching

Post  Cribbs74 on Sun Jul 19, 2015 10:15 pm

Yes, the prop is small.

It can work though, I have even done it myself with the same prop.

What the boys are suggesting is that you run it in a break in configuration (rich) just to get you up and going until you find a more suitable prop for bench running.

The APC prop comes with a large hole, it MUST be centered or it will vibrate like crazy. Spacers are available to allow centering, but in the meantime you could use a piece of fuel tubing or even tape wrapped around the prop screw.

Ron

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Post  getback on Sun Jul 19, 2015 10:52 pm

Man after reading your post went and fixed me another drink drunken  first off , Next time you decide to run that sucker GET SOME VIDEO!! bounce Popcorn What?  I know the feeling when u feel like ur about to bee chased Thumbs Up   What all the above was said BUT , these are just Toys from the 60s and I think you will chatch on soon now !! Get the right stuff , mount that tight , clamper down JED and turn her loose affraid tongue  Eric Beer Cheers  Son Bitch got powered
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Help! Re: First time benching

Post  Cribbs74 on Sun Jul 19, 2015 10:57 pm

balogh wrote:That bench looks nice for a display but may lead to vibrations...I would go for a metal bench e.g. like the multi-purpose COX stand Bernie sells: http://coxengines.ca/engine-test-stand-for-cox-010-020-049-51.html

Otherwise welcome to the CPMFC: COX Prop-maimed fingers club:



Courtesy photo: trophy-picture collection of one of my TeeDee051-s...took the ER assistant a few stitches to make my finger look at least like this.

That's too funny. Bet it hurt though!
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Help! Re: First time benching

Post  PlaidHatter on Mon Jul 20, 2015 2:37 am

Cribbs,
Valuable info, thanks. I do have a syringe, I've been using it to fill the tank. I'll give that a shot.
I did balance the propeller, I found a washer with the same ID as the center screw and the OD that fits inside the prop.
How big of a prop should I be looking at? I'm going to try and find one locally tomorrow, but keep in mind since I'm not actually going to be running any planes I'd like to use the smallest prop that I can.

1/2A Nut,
I really had no idea that propeller size was that critical to these engines' function. I've been scouring the forum for as much info as I can and asking questions like crazy, but I guess there's still always some things that get overlooked.
I'm going to see what billet aluminum stock I have available to mount it to tomorrow, this way it can help dissipate some of the heat as well, also a more appropriate prop (what size?) and maybe some lock nuts if I can find them in such a small size.

Cox24711,
Lol, yes, I think this is becoming well established.

Oldenginerod,
I was attempting to try and give it a good run at this time, but it didn't really go to plan as I really didn't know to expect the intensity of some of these aspects within the first 5 seconds of run time.
A correct prop is in the plans for tomorrow, I got this one balanced as well as I could and I believe it's decently centered, but everything happened so fast earlier that I didn't have time to focus on if the propeller looked off. Haha
But I'm still not hearing what the smallest size prop I could be looking for is, just that this one is the wrong one.

Getback,
Haha! Cheers! Beer Cheers I was actually supposed to take a video when I started but ended up just forgetting to, it would have been entertaining to watch for sure. As soon as the nuts loosened off the back everyone bounced from their chairs and hit the door like I had just released a lion, or a killer bee! Lol.
I really just want a little engine that I can have set up on a station with everything that it needs to function attractively mounted with it. And the fact that you can upgrade parts to get it to perform just makes it that much more up my alley. But I just need to learn more about how this particular engine functions and operates before I can continue. It may be a toy, but it's a pretty awesome and serious toy.

Again thank you all for your input, I value everyone's info. Maybe soon I'll finally get a run that I'm happy with. Lol.

I'll leave this here for your amusement. . .
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Help! Re: First time benching

Post  cox24711 on Mon Jul 20, 2015 2:51 am

i am 12 and i do flying rag with them its so fun starting it in your hand is fun!! lol! lol!
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Help! Re: First time benching

Post  AUjack2003 on Mon Jul 20, 2015 3:23 am

Wow those burns look a bit of pain but you do get over them after a while. lol! lol! lol! lol!
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Help! Re: First time benching

Post  1/2A Nut on Mon Jul 20, 2015 3:24 am

4.5x4
4.75x4
5x3
5x4
5.5x3
6x2
6x2.5
6x3
6.5x2
7x2
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Post  gossie on Mon Jul 20, 2015 3:40 am

6X3 prop. would be good.
Good fuel mix is 50% methanol, 25% castor oil, 25% nitro.
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Help! Re: First time benching

Post  PlaidHatter on Mon Jul 20, 2015 3:50 am

Cox24711,
What's flying rag? And you start bare engines in your bare hands?! Paranoid

1/2A Nut,
So a 4.5 x 4 would be an acceptable prop if I'm looking for the shortest possible?

Alright guys, off to sleepy land, see you all tomorrow! sleep
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Post  AUjack2003 on Mon Jul 20, 2015 5:09 am

A flying rag is basically an 0.49 with a rag strapped to it lol!
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Post  Oldenginerod on Mon Jul 20, 2015 7:53 am

The "rule of thumb" of props is that if you go up one inch in diameter you come down one inch in pitch (the second number in the size). So a 6"X3" will perform about the same as a 5"X4". That's about the size that will give your engine about the right amount of load to run in the sweet spot. So if you're looking for a smaller diameter prop, get one with a higher pitch number.
As for the flying rag, just look it up on youtube.

Rod.
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Help! Re: First time benching

Post  fredvon4 on Mon Jul 20, 2015 9:23 am

Here you go Jack ( on your other thread I told you some of us older guys would fuss about SAFETY!  No!

I have to tell you that the flying rag is a very very bad idea now matter how fun it seems  Huh...

a propeller at high RPM is dangerous and there is absolutely no way to hold a small engine to launch with the rag without your body and face being in the path of of the propeller---if it breaks or the engine decides to come straight at you...you WILL get hurt

Please do not ever do the "flying rag" and don't ever encourage your friends, little brother/sister or anyone to do it
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Help! Re: First time benching

Post  PlaidHatter on Mon Jul 20, 2015 4:29 pm

fredvon4 wrote:Here you go Jack ( on your other thread I told you some of us older guys would fuss about SAFETY!  No!

I have to tell you that the flying rag is a very very bad idea now matter how fun it seems  Huh...

a propeller at high RPM is dangerous and there is absolutely no way to hold a small engine to launch with the rag without your body and face being in the path of of the propeller---if it breaks or the engine decides to come straight at you...you WILL get hurt

Please do not ever do the "flying rag" and don't ever encourage your friends, little brother/sister or anyone to do it

Oh boy, now I've GOT to look up a video! Lmao!
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Help! Re: First time benching

Post  PlaidHatter on Mon Jul 20, 2015 4:37 pm

Ok that didn't look as cool or as dangerous as I first thought in my head. I figured you tie a rag to it and hold onto the other end of the rag. This seems like a good way to lose or damage your engine. Lol.


Last edited by PlaidHatter on Mon Jul 20, 2015 6:26 pm; edited 1 time in total
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Help! Re: First time benching

Post  robot797 on Mon Jul 20, 2015 4:50 pm

starting a cox in the hand i childs play
i did it many times
starting a 26cc in the hand that is madness
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Help! Re: First time benching

Post  PlaidHatter on Mon Jul 20, 2015 6:00 pm

Familiar with this model, I am not.
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Post  getback on Mon Jul 20, 2015 6:46 pm

https://www.youtube.com/watch?v=ph2PMs2-7G4 This is the best flying rag video U will See ..,, .,,. Get the correct equipment and go from there ,,, Jumping ahead will only SLOW you down , there are shotting a 100.00+ $ engine in the air Small Cox Logo lol! Not Mine !! Popcorn
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Help! Re: First time benching

Post  TopBannana on Mon Jul 20, 2015 8:34 pm


*THERE IS A SWEAR*



(not Mine either but heres another)
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Help! Re: First time benching

Post  1/2A Nut on Mon Jul 20, 2015 9:51 pm

What would be cool since it flies stabilized by the rag is add a throttle sleeve an RX, batteries and servo. With the .049 and a 6x3 prop it will make enough thrust to allow you to throttle back and hover the engine if it climbs too high you can always back off the throttle bring it back down 10ft off the the deck and hover it. Low wind days this will work great. But yes wear safety glasses and use a big enough field to fly in away from houses.  The first vid with the .010 is small enough to run in a large back yard. The trick is minimal fuel just enough duration to fly within your boundaries.
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Help! Re: First time benching

Post  PlaidHatter on Mon Jul 20, 2015 10:14 pm

So essentially you can set this up to function as a helicopter as without being able to steer direction?
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