seancorder

My Feedback: (1)

I have an edgeling that has an AME .061 norvel with throttle control. I believe that this engine is not near as nice as the big mig, but I do not really know the difference. I do know the engine is not performing as well as I would like for it to. I have tried several props, and decided that the 6X4 APC is working best for the engine, but it is still very underpowered.
STILL waiting on my .074 which has been backordered for 2 1/2 months at my LHS, so my next option is to make my plane more powerfull.

Will 45% ruin the engine? Will this make it more powerful, and perform better?

Thanks for your input.

DICKEYBIRD

The AME .061's are designed to scream at high rpms. A 6x4 is way too much prop (IMHO) Try a 5.5 or 6x2 APC or 5x3 Cox black to let it run in the rpm range it's designer's set the timing values for. Should be at least 18,000 I'm thinking. Heck, my antique old Tee Dee .049's do that! I have an old pre Revlite Big Mig .061 on a pizza box-like plane and the "hover-prop" for it is a 5.5x2 APC. It loves to get way up there an' holler to be happy. It'll do 19,200 easy at a slightly rich setting....an AME needs to get up higher than that.

You can't really think about "big prop equals more thrust." Big wood will KILL a Norvel. 45% nitro will just overheat your engine unless you reduce the compression (extra head gaskets) and put a TINY prop on it.

Now that I've opened my big mouth, I'm sure the Norvelite clan will jump in and tell you the real story.

Andrew

The AME is NORVEL's high performance offering for the .061 and will have a more robust highend. The porting on the AME (3 large oval ports) gives better induction at high RPM's, but may have a slightly poorer idle and midrange than the BigMig -- the BigMig will have 5 smaller round induction ports. Both engines appear outwardly the same, but can be differentiated from each other by removing the muffler, moving the piston to BDC and counting ports (a small flashlight helps).

NORVEL does not recommend more than 35% stating that "As a practical limit, stay below 35% Nitro, or the wear rate and potential for damage to the engine become excessive. We know that competitors use up to 65% nitro fuels, but they are willing to replace an engine each flight if that is what is needed to win."

The AME is happier at a high RPM and a 6x4 is a bit overpropped. You might look for a 5x3, 5x4, 5.5x3, 5.5x4, or 6x3. The AME's are also a little tighter than the BigMig's and may require some additional breakin. You should get good performance with 20% or 25% nitro. I have had better performance -- easier starting and cooler running -- with fuel that has a minimum of 10% castor.

Some of the guys here have run high synthetic content fuel, but I believe the majority will be running 14% to 20% castor. Unless your engine is still tight, running too lean or too hot, or overpropped, the AME should be kicking butt.

How much does your Edgeling weigh and why do you think it is underpowered? Have you tached you engine?

Heck, even for a COXist, DB gives pretty straight advice -- I really think he is a closet NORVELite.

Tim Wiltse-RCU

My 2cents is that the AME NEEDS pressure to run 100%

LAter,
Tim

Andrew

You're right!! I run pressure on everything and never thought to mention it.

Lynn S

I tried a 6x3 Master Air Screw yesterday on my AME and found that it ran very low rpms. (not sure how low)The only other prop I've run up to now has been a 6x3 cox during the bench break-in and then all my flying has been with a 5x3 Cox.
As soon as you put the 5x3 cox on it, it will be a different engine.
I havn't tached it yet, but will today. I also cut down the 6x3 MAS to a 5x3, its thinner than the cox and turns around 17,000. I'm using 15% nitro fuel with 20% blended oil.
I found that my .049 big mig didn't like the 6x3 MAS at all and loved the 5x3 cox. As Dickeybird has pointed out many times the 5x3 cox "rubber ducky" is great prop for engines that like to scream.

seancorder

My Feedback: (1)

Well, I belive the edgeling is around 12 to 13 ounces, and with a big mig, they are said to be able to hover around 3/4 throttle.

I have put the rubber prop on before, and the idle would not come down enough to land! With a 6X4, at least I could land it :-) I will probably change that though, after reading this. The 5x3 prop seemed to want to go fast, but I don't think it would have hovered... I will try it again.

Sean

Japanman

Try a few props of different brands in the 5X2.5 to 6X3 range. you will find that for various reasons a cox 5X3 will perform very differently to an apc 5X3/ other brands.
One of those props will suit your engine and plane a lot better than the rest.

J.M

Lynn S

I just went out (with the AME)and tried the cut down MAS with 25% nitro fuel and it ran 18,800 but the plane didn't fly that well at all. I put the 5x3 cox back on it using the same 25% Byron's 1/2 A fuel and it turned 19,000 and flew with more speed and power than ever. That prop really kicks in the thrust with the extra rpms. I had only used 15% fuel up to now.

XJet

Just as a matter of interest, I heard that castor doesn't like staying in solution when you're using very high levels of nitro -- and since the Norvels really do need castor, perhaps this might also set the upper limit that can be used.

Bipe Flyer

A 6X4 is too much, try an APC 6X2 with 25% nitro and be patient. It takes time to break in a Norvel, especially the AMEs. Even after break in it will continue to produce more power over the next several tanks.

William Robison

My Feedback: (3)

When running high nitro add 2% amyl acetate to the fuel, it will keep the castor oil mixed. You might more easily find the amyl acetate by asking for banana oil.

Bill.

combatpigg

My Feedback: (3)

I think the 5.7-3 APC was made for the AME 061, they seemed to arrive on the scene at roughly the same time. 30% helicopter fuel with a shot of extra caster agrees well with the AME. I only run mine with a pressure bladder . I have never been able to find any application where a 6-4 prop is the best choice. If you cut down a 6-4 to 4.25", your AME will run very well [if mounted on a clean racer type plane]. The AME should be broken in with a light load prop at a rich scream in the 20,000 + range.

seancorder

My Feedback: (1)

I am going to try an APC 5.5X2 this evening to see what I can get out of it. My hobby shop does not have cox props, where can I order them at?

Sean

Andrew

A GOOGLE search on --- COX propeller --- will give you a lot of hits -- you can check mailorder shops and pricing when you visit their sites.

Bipe Flyer

Tower has COX props.

http://www2.towerhobbies.com/cgi-bin...93p?&C=QBB&P=7

Larry Driskill

How much nitro to use in 1/2A engines is nearly as tough a question as how much and what kind of oil to use. In fact, I bet it is a tougher question as I am convinced "ALL CASTOR and at least 20% of it by volume" is most often the best answer regarding oil type when you are talking plain bearing 1/2As with non-bushed conrods.

First, specifically toward your questions, "Will 45% ruin the engine? Will this make it more powerful, and perform better?"

"Will 45% ruin the engine?" - I doubt using 45% will ruin the engine. I have not run the RevLite Norvels very much, but I ran lots of 35%, 40% and 50% through the first AMEs. They were good engines and I don't think I had any trouble due to high nitro that I could not fix with proper head clearance. But even in National Championship level competitions I usually ended up running 35%, or less. I might not have been at the peak of the power possible curve, but I was closer to the "get a good run every time" goal.

"Will this make it more powerful?" - More Powerful? Probably, but maybe not enough more powerful to justify the added expense and effort . . . assuming you are running 25% nitro or so already.

"Perform better?" Less of a sure thing here as 45% nitro will probably also bring you more sensitive needle settings, shorter glow plug life, higher fuel consumption, and generally more cantankerous behavior.

All the new generation 1/2a engines I have worked with ( VA .049s, Norvel .049s and .061s, Cyclon .049s, .050s, and .061s, and Fora .050s) like to turn up higher than the TeeDees we ran for so many years. I ran my TeeDees in C/L Combat at 24,000 or below. I run the new engines at 30,000 or above.

So . . . for sport applications where you may need the thrust of a 5.5 or 6 inch prop, you will need to try less pitch than the traditional 3" and that, as Dickeybird and others have written in this thread, probably means 2"s of pitch and a 6X2 or 5.5X2. Not that the engines will not run on a 6X3, but even the .061s may be smiling more broadly at the higher RPMs

Finally, Norvels are fine, fine engines and lots of us have had tons of fun with them.

But all 1/2As are just as tough, or tougher, to manufacture than .15s, or .40s. And we want to buy them for less money than we pay for the easier to build .40. Consequently, I think every one of the relatively very inexpensive 1/2A engines are not necessarily created equal and some examples of the same engine of the same brand are going to be stronger than others. Many times the engine that is a bit ‘tight' will end up being the better engine after a careful, albeit longer, breakin.

raddad

Jonesbore hobby shops don't carry cox props. most people don't have the knodledge to run and tune a small engine anyways cuz todays Arf world has deminished the skil in building and tunning small aircraft engines. ask for help from one of your older club members you will be suprised what they know and willing to share. I personaly carve my own props and have great results.
Raddad

Lynn S

My AME is about to hit 20,000 rpm with a 5x3 cox prop. The last time out I use some fuel (25% nitro)that has been opened for several months and it ran 19,000. Today I ran the same brand fuel from a newer bottle and it turned 19,880. It will probably run 20,000 rpm or more after a few more runs.

combatpigg

My Feedback: (3)

When I used to run TDs in combat, it was a waste of time to hook a set of lines up unless you could get 23,500 out of a "maximized" .049 running a 5-3 prop. If you want to get into the power curve, try twisting those rubber blades a little to take some of the pitch out. A good running AME 061 should be giving considerably more than 20 grand with a 5-3. If the crank is polished per LARRYs' instructions, that would only do some good.

seancorder

My Feedback: (1)

raddad:

Older more experienced builders! I could never carve my own prop, I can't even carve a turkey. It is a good thing I have older and wiser club members around...............