Norvel for speed?

.049

I'd guess the Aero combat. It doesn't even have a venturi, you just ram the fuel right into the hole. It'll probably still need a 128tpi needle. Let's wait and see if Ken agrees.
Rusty

RknRusty wrote:I'd guess the Aero combat. It doesn't even have a venturi, you just ram the fuel right into the hole. It'll probably still need a 128tpi needle. Let's wait and see if Ken agrees.
Rusty

That's what I was thinking.

Jim

I have experience using the AME Zeus which is what NV engines lists on their site as the Aero. I run it on a hard tank using case pressure. I have it on a small speed plane currently. The stock needle valves will not work using bladder. Even the Driskill spraybar and needles have their shortcomings . They will work using the venturi, however I remove the venturi entirely and the Driskill needle is too touchy to run in 1/2A combat. The Cox 128 works far superior. While my success has been good, it's hard to offer advice due to certain factors. These engines don't like a lot of pitch. Pitch is what's needed to go fast. I run Russian glass props on my AME. I've heated and tweaked the blades for slightly more pitch. This could also be done on a APC. These engines though need thin blades to run correctly. The Aero isn't afraid of nitro and we commonly run as much as 40-60% in them. Here's a picture of it. Currently I'm having issues with the tank. I believe I need to pull the pickup tube slightly out of the rear corner. I might also pinch down the rear corner. This is very problematic when your trying to run speed if you use a typical square backed tank. Bladder is the obvious solution. Ken

Ken,
Cool looking plane! How is performance on 10%, per AMA guidelines?

Thanks,
Jim

Neat plane Ken. Looks like a marriage between a Ringmaster and a Banshee.

Jim, the AME Zeus in my experience here didn't behave on bladder on 10% fuel. Seeing you want to run FAI fuel, this may take some experimenting. I run a lot of full synthetic fuel in these engines. I use 30% nitro heli fuel with 24% oil but full synthetic. If I do run castor fuels, it's usually 17-18%. Whenever I tried to run 10% on this engine, it would cool the plug off and it would run ratty and die about 1/3 of the way around the circle. Once you started pumping the nitro to it, it would come alive and stay lit. The 10% may work with the stock plug setup, but it didn't with the Nelson/ Galbreath. The hot plug didn't work well with it either. I haven't tried the Merlin plugs on this engine , but I see you had some Glo Bees in your TD which also might make things come alive. My glass prop is approx a 4 13/16" x 3 pitch. I tweak the blades a little though. Ken

Cribbs74 wrote:Neat plane Ken. Looks like a marriage between a Ringmaster and a Banshee.

It does look like a ringmaster and a banshee had a baby.  

I just ordered a norvel .049 aero and some Merlin flat coil "glo bee" style plugs, hot and medium. Got the lowdown from Rusty on his fine thread needle setup. Let's find out how fast my son can spin in a circle!

Jim

Where did you grab the glo bee head? I have a bunch of plugs, but no head.

Edit: nevermind. I assume you will use the norvel head.

Merlin's site is so non-descriptive, I've always been confused as to what's what.
What's the difference between a 2019B and C flat coil and a 2019? What's a flat coil? Are the 2019 the ones Bernie sells? is that the 2020 clamp ring he sells too? Which ones are the stock Norvel plugs? And the ones called Drop-ins on the bottom right, what are those, do they also fit Cox and Norvel? Please enlighten me. Is the 2020 clamp ring for all of these?
Thanks,
Rusty

The flat coil is a wierd flat shaped coil if I am not mistaken. It's not really a coil, but more of a crooked line. Think circuit board runs.

Those are the ones I have.

GloBee flat coil.

RknRusty wrote:Merlin's site is so non-descriptive, I've always been confused as to what's what.
What's the difference between a 2019B and C flat coil and a 2019? What's a flat coil? Are the 2019 the ones Bernie sells? is that the 2020 clamp ring he sells too? Which ones are the stock Norvel plugs? And the ones called Drop-ins on the bottom right, what are those, do they also fit Cox and Norvel? Please enlighten me. Is the 2020 clamp ring for all of these?
Thanks,
Rusty

2020 is the clamp ring Bernie sells, 2019 is the insert. So 2019a is the ring and three inserts for $15. Pretty good deal.  I have bought it and it is exactly the same. The glo bee flat coils are supposed to fit the ring. I will report when they arrive.

Jim

Well shoot!

I had the right stuff all along. I was going to use the glo-bee setup for the tach race, but couldn't find the clamp. I had a couple on other engines and didn't realize.

The original Glo Bee made 3 different types of plugs. One was a sport version, and one was a racing version. The coils were the same but the combustion chamber was quite different. One and I can't remember which took almost 7 gaskets to make it work and I believe it was the sport. The other  Glo Bee was the drop in plug  which was very small only about 1/4" in diameter and this used a very small clamp ring. The clamp ring that I use for this plug is a burnt out Nelson plug. I drill the center post out and this is used in conjunction with the Galbreath head. Larry Driskill had the last of the originals that I know of. Here's a close up of the current Merlin drop in http://shop.sam-rairacing.com/Merlin-Racing-Glow-Plugs-GloBee-Drop-Ins-MGP-GB10.htm  

This plug won't work with a standard clamp ring that you find with the Merlin or standard Glo Bee plugs. You have to use the specified clamp or use a burnt out Nelson plug and drill it like I mentioned. The cylinder head be it entire head or button requires a tapered seat. Note the bottom of the plug has a convex shape which would seal in the Galbreath head. A standard Merlin or Glo Bee is flat.

The next problem you would encounter is all the different center diameters. All of the Merlin plugs fit Norvel's, Cox, Stels, AP etc. What won't work is the center post of the plug in just one clamp. I either turn the plugs to all fit one clamp ring or  drill out the clamps that are undersized. The Glo Bee has the smallest center section . A actual Stels plug will however swap out with a Glo Bee head clamp.

Al Kelly is the owner of Merlin plugs. He can somewhat difficult to contact. If you wish to ask him questions you MUST fill out the contact form in full and he will call you back. It will take some time though. I don't believe e-mail gets checked on a daily basis. Ken

I can't comment on the reliability and performance of the Merlin drop in plug. I have a decent supply of Glo Bee plugs left. The Glo Bee plugs work performance wise very well. The problem is their reliability is horrible. They either work, don't work or blow at any given second. Nelson plugs in my opinion work far superior to any given plug on the market not to mention their cost is far lower than any one given plug.

That pretty much covers it, thanks for the answers and info. Now we can get back to the main topic.
Rusty

Just spoke with Al Kelly, the glo bee 2019B&C are designed to work with the 2020 cox/norvel clamp ring.

Jim

Just recieved the Merlin Glo Bee plugs, flat coil direct drop into the cox international style heads. Will give them a try tomorrow.

Jim

Cool, they do fit. I had a bunch of plugs and no clamp, or so I thought.

Well, initial "just screwing around in the backyard" test have them about 1000rpm slower  than the Nelson/Galbreath combo.

Jim

What's the reason for using a flat coil rather than a helical coil. More exposure to the methanol?
Rusty

I've wondered about that myself.