Norvell .049

I was recently given a Norvell .049 by a local combat flyer. He tells me that the venturi has been opened up a bit to allow for a bladder type tank. I would like to use this motor for a 1/2A stunter ( a mini Chizler if you will) to do battle in Leprechaun Stunt at next months Palmer Classic. What would be the ideal venturi size for an optimal stunt run? Prop? Larry, NorCal Circle Jerks.

Actually, why not just go with the bladder tank? They give awfully good, steady runs.

And, there is a surprisingly good guideline in 1/2A stunt:

"He who gets a good engine run wins!" That works out all too often! Unless you are John Wright. It doesn't seem to matter how his engines run, the plane flies a great pattern anyway.

>Actually, why not just go with the bladder tank? They give
>awfully good, steady runs.
>
>And, there is a surprisingly good guideline in 1/2A stunt:
>
>"He who gets a good engine run wins!" That works out
>all too often!

Or even "He who gets his engine to run at all wins!", based on my numerous painful experiences judging WAM 1/2A contests out in the Central Valley sun.

LAST EDITED ON May-13-04 AT 04:43 PM (CDT)
 
>I was recently given a Norvell .049 by a local combat flyer.
>He tells me that the venturi has been opened up a bit to
>allow for a bladder type tank. I would like to use this
>motor for a 1/2A stunter ( a mini Chizler if you will) to do
>battle in Leprechaun Stunt at next months Palmer Classic.
>What would be the ideal venturi size for an optimal stunt
>run? Prop? Larry, NorCal Circle Jerks.

I have a 1/2a combat and a 1/2a stunt with a Norvel .049 on them both with a bladder. I have not drilled out the venturi the engines work fine like they are. Screw the needle in all the way then screw it out about 1/2 turn to start engine. I tried a 6x3 prop and the air airplanes are both very fast about 70 mph. I tried a 3 blade 5x3 prop it slowed the airplane down a little but its still very fast. I can not find a 6x2 prop not sure there is such a thing.

I think a 6x2 prop will show it down to a reasonable flying stunt speed for 1/2a.

My engine came with a fuel tank that held only 3 minutes of fuel. I later changed it to a bladder.

6x2 APC props are readily available from towerhobbies.com. Also a 5.5x2, 5.7x3 and other wierd sizes.

Gary says That these things are very fast, but I dont want very fast. Which is why I would like to know the original venturi size. I would think the proper size would give a steady stuntable run.Larry, NorCal Circle Jerks

>Gary says That these things are very fast, but I dont want
>very fast. Which is why I would like to know the original
>venturi size. I would think the proper size would give a
>steady stuntable run.Larry, NorCal Circle Jerks

Larry,

Love your optimism as to a "steady, stuntable run" from a 1/2A motor.

LAST EDITED ON May-13-04 AT 08:20 PM (CDT)
 
Larry, is it a AME or BigMig. The AME version is the high performance version for Combat. It will not run on suction.

Usually you can tell the difference between the 2 version, simply by the needle valve. The AME needle valve is point straight out, 90 degree from the crankshaft. The BigMig is angled back about 45 degrees.

The motor in question has the needle angled back at about 45 degrees. So I guess its a Big Mig. Larry, NorCal Circle Jerks

Thanks for all the help guys.

I think I read on the forum that if you put the prop on backwards, it will slow the plane down. I always thought if you put the prop on backwards, the plane would fly backwards, but that's how much I know. It might be worth a try.

Carl,
Putting the prop on backward was a good trick when you wanted less thrust. I am not sure whether the lower thrust was due to less efficiency, or maybe due to less effective pitch just producing less forward speed.

But it does work. It only goes backward if the darn reed valve engine is running backward. Makes for some unusual launches if you don't notice!

LAST EDITED ON May-13-04 AT 09:18 PM (CDT)
 
Larry,
I just pulled the screen off my Norvel Big Mig 049. The shank end of a 38 drill (0.101) won't go through, while a 39 drill (0.099)does. So I "miked" both and the shanks measures out at 0.1008" and 0.0983" respectively. Since these engines are Russian, the diameter might actually be 2.5 mm! 0.10" is good enough!

This was one of the original ABN 049's (not the newer RevLite). I had my best success using a cutdown black Tornado 5-3 (cut to ~4.75). This engine likes to rev. Best results were using ~45 foot lines on a 1/2A FliteStreak (old Top Flite kit).

Good luck.