Hi Josh. I just spent 45 minutes writing a reply to your post, and the damn thing disappeared when I clicked Send.

Please e-mail me at rknrusty at AOL dot com, and we can talk about these engines.

Rusty

admin wrote:
Right, with pressure, you start with the needle set much leaner than normally vented... or else it floods. The Big Mig runs very well on normal suction, but for C/L stunting, pressure will keep the fuel feed more steady during high gee loops, wingovers, inverted, etc.

Have you gotten it running on pressure since you first posted?

Rusty

I'm not sure about the prop on an .074. Type this into Google without the quote marks, and you should find it:

"Norvel .074 prop site:rcgroups.com"

Or this:

"Norvel .074 prop site:rcuniverse.com"

Good luck,
Rusty

Guillows kits are pretty small aren't they, how big is yours? You have a very fast engine after it's fully broken in. I flew a Big Mig .061 on my 6oz, 24" wingspan self designed stunt plane on 40' lines, and it was turning 2.5 second laps, or about 73mph. I didn't think it was ever going to run out of fuel that day. I had to do lots of lazy 8s and loops just to ward off the dizzies. And your engine is faster than mine.

It was much more comfortable on 45' lines. I usually pump 3/4oz of fuel into my pressure bladder. I haven't timed it, but I think that's about 3 minutes of flight running screaming full speed, maybe more. An APC 6x2 prop lets the engine run fast enough to be happy and cuts the speed considerably. I use that on my 7.2oz Baby Flite Streak and can manage it easily on 35'. The 6x3 prop that NV recommends is really too much load on the engine. These engines are meant to unwind at high RPM so as not to bog in loops.

Please don't turn your Guillows back into a pile of sticks, and post back to let us know how it goes. If you need quick advice, you might want to try RCgroups.com in the "Control Line" and "Engines" sections, or coxengineforum.com in the "Other engines" section under "Models and modeling." There are lots of knowledgeable Norvel users there.

Sorry NV Administrator, I hope it's okay to direct members to other sites. Please let me know if it's not. Just want to help the guy out as much as possible.
Rusty

metalhead100 wrote:
Ah, so it does. Nice looking helicopter, those are amazing machines.

I'm just curious, Metalhead, have you got one of the new NV engines or an older Norvel? I'm curious if the NVs are still built tight like the old Norvels, or do they make them looser so the inexperienced masses don't have trouble getting them running?

I think the instructions for cold spinning a new engine with castor to reduce the pinch is part of dumbing it down to prevent complaints from mechanically challenged "modelers." That is actually very bad for the engine. Rather, a new one should be heated with a heat gun before cranking to naturally relieve the pinch, instead of grinding it down and ruining the Revlite coating. Their recommendation of a 6x3 prop on .049 and .061 airplane engines is equally baffling. These engines are meant to run high RPMs and the larger prop won't let them spin up.

I guess if they don't make it easy, they can't stay in business. Understandable but disappointing.

I don't know if it's just my browser but the pictures are cropped. I ended up linking to my pics on Photobucket.com.

According to the engine guy at Sig Mfg., as quoted on RCUniverse, when they were the Norvel distributor, the engines came in new either way. He said whenever he assembled one, he put the hole on the lead edge of the sweep as viewed at Bottom Dead Center. That's the way I put mine, but I can see good arguments for both directions.

Just as I thought. I've run into some righties lately and thought I should check.
Thanks for the reply.

Hi Colin. Not much happening around here. I searched and tried to find you a useful answer. I was hoping to tell you the Merlin Glo-Bee dropin plugs work but they must be smaller or something. They're almost identical to the Norvel .049 and .061 plugs. The head clamp on the .074 must be too large for the same drop-ins as the smaller Big Migs.

Everything I could find already posted on Rcgroups and RCuniverse was about the adapters for standard plugs, and those are said to come with an inherent drop in RPMs. The plugs these engines have when new must be available somewhere. Damned if I can find it though.

I would suggest posting on either of the two forums I mentioned above. RCgroups.com has plenty of active members with Norvel engines. Good luck.
Rusty

On a Big Mig, holding the engine with the cylinder vertical and looking at the connecting rod, which side should the oil hole be on, left or right?

Thanks,
Rusty

I have a new kit built Baby Streak and it's built lighter than the older one I've posted here. This new one has a Big Mig .061. I have it tamed a bit with a 6x3 MA prop. I'm planning to try some different APCs just to see how they do. I know the engine would probably be happier at a higher RPM. But anyway, here it is today with the 6x3.

Fullscreen is enabled. If it's jerky, set it back to 480p.

Okay, I'll give it a try. I guess you could call the one I'm using a Super-fine thread. My bladder is pretty thin so the pressure isn't too high.
Thanks, admin.
Rusty

Does anyone know where to get fine thread needle valves for a Big Mig?
I like to run pressure bladders on my aerobatic planes, and that requires a fine NV. I have one fine thread NVA that was made by Larry Driskill at kittingittogether.com. but he no longer makes them. I can probably cobble a remote one together from one of the few remaining Cox product engine backplates, but they were rare back in the good ol days. I don't know that they are long enough to press into the screw holes in the engine, minus the venturi. That's a helluva hole too, probably needs a restrictor added on after pressing in the NV.

Anyone else here use these? Surely there are some combat guys/girls around that still use them.
Thanks,
Rusty

Yeah, I knocked some of the pretty off the canopy and bent the fine thread needle with that inverted landing. The next time out, this past Sunday, I sealed the venturi with a ring of latex bladder tubing and put a shorter 5.5x3 prop on it and it didn't bog any more. It was not happy with the 6" prop the first time out. I don't know why NV Engines recommends that size.

This time I launched at 22,300rpm. It screamed around the sky with a death wish. I really had my hands full. I think I better add a few more feet of line to tame it. It was a wild flight. Luckily I could stand still and do loops and 8s to get my balance back. The Norvels sure do blow the wings off my Tee Dees. A club member has given me two more Big Migs and I have another Baby Flite Streak that's going to get one.

I forgot to post this. I took it out last Sunday. Never having flown a Norvel, or this plane, I tamed the engine with a 6" prop. It flew great and looks like I hit the CG right on the mark with no balancing weight. Pretty lucky.

So anyway the first flight was the best. This engine has a venturi that refuses to seal, so I had Permatexed it. Don't ever do that. The RTV started melting after the first run, and I found later it had formed a deposit on the glow coil. I videoed a flight though and you can hear the venturi leaning it out a few times. I have that fixed now for the next excursion, along with a smaller prop, but here's what I got my first day out:

Full Screen is enabled

Thanks for the help, Admin.

I got my first Norvel engine this Summer, an .061 Big Mig that looks like a new old stock engine from Russia. I fretted over getting it cranked the first time but finally got it pretty well bench-run-in. I'm going to fly it this weekend on a plane that I built just for it. It should be a screaming little hotrod and I'll take the video camera to catch the action. Hopefully it won't need much trimming.

About two years ago I built a Goldberg Li'l Jumpin' Bean, 21" wingspan to learn to do stunts with. It went through hell and back as I figured out how to do loops, 8s, wingovers, etc., all the time with a Black Widow and then a Medallion. It finally became so demolished it was impossible to repair. Especially when the bellcrank broke loose and gutted the inboard wing.

I finally cut off everything but the center of the fuse around the wing root and rebuilt it from scratch. All new ribs, wingtips, relocated the bellcrank and added a beam mount and two tail booms like a Li'l Satan. I also increased the wing area with static flaps to give it better wing loading with the more powerful Norvel.

Here's what it looks like now:




It ought to be a hot little stunter with the .061. I plan to take it out this Sunday.

Hopefully I'll have some entertaining flight video soon. I've been working on that old Jumpin' Bean for a couple of months now and I'm really looking forward to flying it. I renamed it the Refried Bean.
Stay tuned,
Rusty

I shot the venturi retaining nut across the shop today and don't know if I'll find it or not. I had to rob my only other Big Mig to replace it, Can someone tell me what size screw and nut I need to look for to replace it?

Also, next time I open up the engine, I want to replace the four head bolts with some that are a little bit longer. That way if I ever bust a cap off. I can grab it from the bottom.

But right now I really need the nut that secures the retaining bolt that holds the venturi on. If someone knows the size I'd greatly appreciate it. Thanks,
Rusty

Thanks Victor. I'm building a new plane for my first .061, the one I was breaking in a couple of months ago, and it should be a mean little control line hotrod. I'll post another flying video as soon as she's ready to fly. Soon I hope. I'm covering it now.

The grungy old .061 I got yesterday is soaking in fuel now and looks good. Still has a nice pinch at TDC and all the internals look clean. I've got another Baby Flite Streak for it as soon as I can find a fine thread NVA for the bladder.

I have a Revlite Big Mig .061 with a polished prop driver and new type muffler retainer, and it has "10" stamped on the side of it. I was recently given another engine that looks just like it, obviously Revlite, polished prop driver, but with the old style muffler retainer spring, and it has "61" stamped on the side. He told me it was an .049, but I'm thinking the "61" stamp means .061 cubic inches. Is this right? Do some .061s have "10" and others have "61" stamps?

www.servimg.com/image_preview.php?i=104&u=16760059

Thanks,
Rusty