Babe bee and balloon tank

It will work, but usually a 1/4" hole is drilled in the side of the tank to get the line to the balloon. Same method as used for a bladder for some of the free flight guys. It kind of ruins the tank for normal use again. Ken, I tried moving the bladder tube parallel to the bellcrank on an F2D combat and used a balloon tank. I tried one with perforated tubing inside, and just having the tubing peeking in a bit. Same result, cutting after a lap. Used an AP .15 with a fairly small venturi, and both suction and muffler pressure. Any ideas? Just don't like bladders. Tried a hard tank too, and it was a bit better but would cut on outside loops.

Thanks guys , also can I mont the bladder under the engine ?

pressure bladder can be any where all the way out to your handel.....tho the long fuel line adds a ton of drag....grin

balloon tank is same as any other vacuum feed tank and needs to be centerline of nva..too high will flood...too low will not draw properly

for stunts you want tank neutral draw up down inverted flight

We need to watch that we don't confuse people about the use if terminology here. A balloon tank and a pressure bladder are two different things. The balloon tank (an actual kid's balloon) is merely filled with fuel but not inflated. A bladder (usually a peice if surgical tubing I think) is inflated under pressure. The balloon relies fully on fuel draw by the venturi wheras a bladder forces fuel into the engine.

Oldenginerod wrote:We need to watch that we don't confuse people about the use if terminology here.  A balloon tank and a pressure bladder are two different things.  The balloon tank (an actual kid's balloon) is merely filled with fuel but not inflated. A bladder (usually a peice if surgical tubing I think) is inflated under pressure.  The balloon relies fully on fuel draw by the venturi wheras a bladder forces fuel into the engine.

Can I just add (before anyone questions my qualifications) that I don't consider myself an expert in any way, having never used either type of tank system. I've just learnt heaps of good stuff over the years from other more knowledgeable members here and I give them the credit for anything that I know. I just find that if there's something comes up that I know about, I can't help myself and need to comment (hopefully for the benefit of others).

Rod.

Oldenginerod wrote:

Oldenginerod wrote:We need to watch that we don't confuse people about the use if terminology here.  A balloon tank and a pressure bladder are two different things.  The balloon tank (an actual kid's balloon) is merely filled with fuel but not inflated. A bladder (usually a peice if surgical tubing I think) is inflated under pressure.  The balloon relies fully on fuel draw by the venturi wheras a bladder forces fuel into the engine.

Can I just add (before anyone questions my qualifications) that I don't consider myself an expert in any way, having never used either type of tank system.  I've just learnt heaps of good stuff over the years from other more knowledgeable members here and I give them the credit for anything that I know.  I just find that if there's something comes up that I know about, I can't help myself and need to comment (hopefully for the benefit of others).

Rod.

Comment all you want. I have tried all three tanks and none have worked that well. I guess the pressurised bladder works good, but I don't have the speed required to get the clamp off the tubing every time. Yes surgical tubing is common, pen bladders and pacifiers were used. A bit hard to find nowadays. There is a little red cap that works OK for pressurised systems. It is a lower pressure than the surgical tubing for easier needle settings. I think the OP is thinking of using the limp balloon. They are all good for not having air in the tank for the most part.

Thanks guys, and Rod , thanks for clearing that up , I thought they where the same

Oldenginerod wrote:Can I just add (before anyone questions my qualifications) that I don't consider myself an expert in any way, having never used either type of tank system. I've just learnt heaps of good stuff over the years from other more knowledgeable members here and I give them the credit for anything that I know. I just find that if there's something comes up that I know about, I can't help myself and need to comment (hopefully for the benefit of others).

Rod, I think not an apology is required. Only a very select few may be considered as ultimate authorities. Larry Renger used to post in these forums among a few others. Most here vary in experience, some very experienced here and there and others not so. I am more among the not so, but what I have learned is still of value to some as we all have different experiences, which helps to fill gaps, confirm what others have observed, or add a new twist to shed light on something not considered or tried before.

All learning experiences are of value. All research with discernment is of value. And, the gentle correction by the more experienced to the lesser experienced is also greatly appreciated. We all learn from each other.

No one person has the corner on the market, but each specialize in a special way to shed light to others their successes. I think this is what makes this forum unique.

I am surprised Ken didn’t elaborate. Yes you can use a bladder or a balloon tank except the baby bee as designed can use neither.

Also mentioned you will will have to drill a hole in the stock tank and attach the balloon through a small diameter fuel line to the backplate nipple. However, a bladder would require a complete re-work of the needle valve as the stock needle is too course to work properly under pressure.

What I would suggest for either setup is using a horseshoe backplate as seen in RTF’s standard needle for balloon and fine thread needle for pressure.

I’ll also suggest purchasing a TD or Medallion as they are far superior performers with the fuel delivery you desire.

Ron

My day yesterday became involved with replacing my brake lines . I see a lot got posted here. One thing that hasn't been mentioned is the procedures needed to fill the tank. Fred mentioned about having the tank on the engine centerline, that's not as critical as it is using a hard metal tank. Because the head pressure inside the balloon isn't the same as being in the tank.

Whenever I have used a balloon tank I take my syringe and withdraw the air in the balloon. With the syringe still attached, I use my pinch off to squeeze the fill line which maintains a vacuum inside the balloon. Fill the syringe with fuel and purge the syringe of any air the same way a doctor does prior to giving a injection holding the tip up and squeezing until just a spurt of fuel exits. Then insert the syringe and fuel the balloon. AT NO TIME DO YOU EXPAND THE BALLOON. In other words if your filling the balloon and it becomes expanded and under pressure, this tank won't work. If your filling the balloon and expanding it, the balloon is too small. Using the syringe, you should be able to offer the balloon a predetermined amount of fuel every time by using the graduations on it. Of the examples I have seen working, many used a 35 mm film canister as a holder for the balloon glued or zip tied to the side of the plane with the lid in place and holes drilled through the lid.


My pinch off or hemostats are in place up to the point the engine is running. You prime the engine and burp it out getting it to run on prime only. When ready for start, prime again, get it fired on prime and prior to it running the prime out release the pinch off and it should maintain.

Alan, I'm a dyed in the wool bladder user when it comes to F2D or combat. I did use the AP .15 short term for .15 combat we were doing. I put a lot of high expectations on the engine and it didn't fulfill my needs. However, the engine for the price was very well designed and made.  Global distributors were selling these unboxed in plastic bags at one point for $30 making it a good choice. My engine was a r/c version. You mentioned a small venturi, I know they offered a control line venturi for this engine, but it was too large for suction use. I'm gathering you had something to fit or had one made?

             You posted your dilemma but essentially what I'm reading is that your plane just dies on the outside maneuvers. Was it shutting off from being too lean or rich? Is the fuel load too far away from the engine?  You also mentioned the use of muffler pressure, the muffler on the AP is absolutely horrid and it robs in excess of 1000k rpm's. However, if you have to use it I can only suggest that you place your fuel balloon inside of a larger balloon. Then you can separate your muffler pressure from your fuel load by using the muffler pressure outside in the larger balloon. This way the muffler pressure can assist in collapsing the inner balloon and insuring positive fuel delivery not too mention ridding the fuel balloon of it's contents. A balloon Tettra tank so to speak

aspeed wrote:

Oldenginerod wrote:

Oldenginerod wrote:We need to watch that we don't confuse people about the use if terminology here.  A balloon tank and a pressure bladder are two different things.  The balloon tank (an actual kid's balloon) is merely filled with fuel but not inflated. A bladder (usually a peice if surgical tubing I think) is inflated under pressure.  The balloon relies fully on fuel draw by the venturi wheras a bladder forces fuel into the engine.

Can I just add (before anyone questions my qualifications) that I don't consider myself an expert in any way, having never used either type of tank system.  I've just learnt heaps of good stuff over the years from other more knowledgeable members here and I give them the credit for anything that I know.  I just find that if there's something comes up that I know about, I can't help myself and need to comment (hopefully for the benefit of others).

Rod.

Comment all you want.  I have tried all three tanks and none have worked that well.  I guess the pressurised bladder works good, but I don't have the speed required to get the clamp off the tubing every time.  Yes surgical tubing is common, pen bladders and pacifiers were used.  A bit hard to find nowadays.  There is a little red cap that works OK for pressurised systems.  It is a lower pressure than the surgical tubing for easier needle settings.  I think the OP is thinking of using the limp balloon.  They are all good for not having air in the tank for the most part.

I was totally against using a bladder, until I was forced to have to use one. I always thought I’d flood the engine, or never get the clamp off soon enough. I found some tutorials on bladder use and the suggestion that the clamp be removed while pinching the line before starting so that your finger pressure regulates flow. Run on prime to get some heat in the engine, pinch line with finger and thumb, remove clamp. As soon as the engine fires let go of the line and you should be good to go. Needle at your discretion. I use an IV pinch as my clamp.