TD .049 powered trainer and wedge tank location.
 

I am in the process of renovating an old 80's, 26" span CL trainer for my grandson, which was a construction article in a copy of MAN back then. It was originally powered by a Cox .049 Baby Bee which after countless flights teaching my son and several of the neighbourhood kids to fly, has done its time.

I plan on using a TD.049 with a 2 oz. wedge tank, but having forgotten most everything regarding CL planes, I need to know where should the tank outlet be in relation to the engine's needle valve and how far away can the tank be located. Thanks

RE: TD .049 powered trainer and wedge tank location.
 

A two oz wedge tank is going to give you more run time than you want, like 10 minutes, or more. For a trainer a smaller tank would be better. Get it as close to the engine as you can, and more or less vertically line the fuel pickup with the needle valve. I assume it is the usual double vented stunt tank.

RE: TD .049 powered trainer and wedge tank location.
 

Karolh,

Remember also that the TD will have about twice the power of a BabeBee. I would suggest a 6x2 prop to slow it down some, and use longer lines.

Another possibility would be to repair your old BabeBee or locate a used one for a few bucks.

In any case, good luck with it.

George

RE: TD .049 powered trainer and wedge tank location.
 

I realize that the run times will be quite long with a two ounce but can find nothing smaller. I might just have to use it half filled. I can remember the days when we made our own tanks from empty milk tins and copper tubing.

RE: TD .049 powered trainer and wedge tank location.
 

George,

I never gave the extra power from the TD much of a thought, thanks for raising the point. Using the TD is really a last resort for me as I tried getting a replacement Baby Bee, but here those things are not just laying around. Guess I more than likely will have to run the TD off peak.

Karol

RE: TD .049 powered trainer and wedge tank location.
 

Karol,

I empathize with your plight. Do you know what is wrong with your Babe Bee? Perhaps a simple parts replacement will put the old gal back into flying trim. My link to the Cox web site appears to be broken, but perhaps someone has a good one.

Additionally, one can usually pick up Babe Bees and parts relatively cheaply at (GASP!) eBay. Don't skip the the engines without tanks. They can usually be had for less money than the engines with tanks. They will bolt on to your existing tank with no modification. At the very least you may end up with a new glow head for less than the current price Cox charges. See:

[link=http://search.ebay.com/cox-engin_W0QQfkrZ1QQfnuZ1QQfsopZ1QQsatitleZcoxQ2aQ20e nginQ2a]Cox Engines[/link]

Maybe your engine just needs some TLC after sitting a long time. Maybe a bit of fuel in the cylinder will loosen it up and breathe life back into her.

RE: TD .049 powered trainer and wedge tank location.
 

Truth of the matter is that I loaned the model to a friend about six years ago to help start a CL club for the kids in his area. Asked him a few weeks ago if it was still alive and he said yes.

When it was returned it came minus several items, prop, prop nut, needle valve and the plastic tank was busted and was just in a general overall state of disrepair.

Needless to say I was a bit disappointed as I had loaned it without my son's permission, but it was all for a good cause. I thought about building a new model but my son would hear none of that, wanting his 7 year old son to learn on the exact same model he did.

I visited the new Cox website and saw their Sure Start 049 which would be ideal for this model, but the hastle to get one here is just too much. I have just about exhausted every possible option I can think of locally to get a replacement, but to no avail.

With my grandson now tugging constantly at my leg I have no alternative but to put the TD into service. Though at least 20 years old it is NIB and has never been run.

Guess I am having as much fun getting this memories packed 25 yr. old model back into the air, as he will have flying it.

Karol

RE: TD .049 powered trainer and wedge tank location.
 

In it's present form the fuel inlet nipple on my TD .049 engine is on the left side of the engine, but in order to have it as close as possible to the fuel tank, I want to swap the complete needle valve assembly around to have the nipple on the right hand side of the engine.

From all indications this seems a straight froward change by pulling the venturi locknut, taking off the assembly, turn it upside down while swaping ends and tightening back the venturi, but I just want to be sure it's okay to do so. Thanks.

Karol

RE: TD .049 powered trainer and wedge tank location.
 

No problem. Just be careful to get the venturi tight but do no harm to the plastic holder thingie. If you still have a low compression head as on the Baby Bee, that will slow the TD down some.

RE: TD .049 powered trainer and wedge tank location.
 

Jim

I gather from your reply that the Baby Bee's glow head can be used on the TD to de tune it a bit....that's a great idea as I do have a couple of those lying around.

What is the best brew for these little jewels.

Karol

RE: TD .049 powered trainer and wedge tank location.
 

Krolh,

Should your TeeDee need further detuning, try putting the prop on backwards. That will slow it down, too.

RE: TD .049 powered trainer and wedge tank location.
 

Adding an extra glow plug copper gasket or two will further detune it.

For your purposes, I would use 15% nitro and 22% oil (at least half castor).

George

RE: TD .049 powered trainer and wedge tank location.
 

Thanks George.

RE: TD .049 powered trainer and wedge tank location.
 

Just a thougt, wouldn't a T.D. fit on norvel tank if one of those is available? Then wouldn't it mount on the plane just like the baby bee did?

RE: TD .049 powered trainer and wedge tank location.
 

Yes. The TD and NORVEL .049/.061 have the same mounting holes. One caution, it does not work the other way around sometimes because the NORVEL crankcase is just a tad wider.
With either the TD or NORVEL on a NORVEL tank it will change the balance. The Babe Bee is a short engine (backplate to prop) when compared to the other combination. Might work though. Tank mounting holes are the same.

George

RE: TD .049 powered trainer and wedge tank location.
 

We have no local hobby shop here in Jamaica, so most all our stuff comes from the US or from our modelling pool.

We have learnt to adapt and use what is available here if at all possible. The 1/2 A size models enjoy very little if any popularity here, that is why finding a replacement B/Bee engine met with no success, much less finding a Norvel fuel tank.

You guys having everything at your finger tips or within easy reach don't know just how lucky you all are.

Karol

RE: TD .049 powered trainer and wedge tank location.
 

Karol

I should have been more considerate of your situation. While there is no hobby shop in the town where I live, there are a few within a hundred miles of here. Also for most of the US, mail order is a possibility. I have heard of using several kinds of small containers for fuel tanks, I have even heard of using surgical tubing in such a way as to end up with a pressurized system. Using the larger tank that you mentioned earlier may be one of the easier options. Keep in mind that the fuel will be "slung" to the outside of the circle so be sure that the intake inside the tank is positioned accordingly. With a few trial runs and a little practice you should be able to measure the right amount of fuel to result in the run time that you want. As mentioned by GCB, be sure your overall balance is correct. Most important, enjoy.

Wayne

RE: TD .049 powered trainer and wedge tank location.
 

No problem Wayne, just the stark reality of living in a third world country while having a first world hobby.

RE: TD .049 powered trainer and wedge tank location.
 

Hi Guys,...

With all this talk about COX 049 engines, its got me thinking about some aftermarket cylinder heads that I once saw. These cylinder heads screwed onto 049 cylinders but were drilled and tapped for normal glow plugs! Therefore one could use regular FOX glow plugs in their .049 engine.

Does anyone know where to get these cylinder heads? Who makes them? Would these cylinder heads decrease the performance of the engine or make them even more finicky?

Sincerely,
Steve T.

RE: TD .049 powered trainer and wedge tank location.
 

Steve,

NORVEL makes one. Be prepared to lose some RPM. Apparently the loss is from how the threads on a glow plug fit.

If you want a screw-in plug, you might consider a Galbreath head and Nelson plug. It's not the standard 1/4x32 threads though. Available at "Kitting It Together."

George