taildraggerdave

My Feedback: (1)

Hello again,
As my Raptor 30 breaks in further, I seem to be having a problem keeping it running below hover setting---I can hover for the entire tank of fuel fine, but if I set it down early and lower the throttle, it dies.
I fiddled with the needles a bit and would refly it and it would die around 1/2 throttle on the way up--just before it lifts off.......
I've been flying behind my work so I went and got a 55 gallon drum, put the heli on top, kneeled down next to the drum and ran it up to about 1/3 throttle and started turning the low speed until the revs picked up. Wow, I was off by a lot. Unfortunately, I don't remember if I was rich or lean as I turned the screw each way then peaked it and I was more concerned about the spinning rotor over my head
Don't have enough in me to try full throttle like that but I felt pretty safe up to half throttle. I flew it again and it is much better.
So here's the question. If most guys set it and then fly it, how are you ever sure that the mixture is set right? My fixed wing background says to go wide open then richen just below peak, but how can you do that with a heli--safely?
Thanks in advance, Dave

Spaceman Spiff

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Most likely it is getting too hot.

helis need extra fuel to keep them cool, so you tune them by temperature. Most folks just check it by touch, but others get thermometers, you can get a nice IR thermometer from tower hobbies for 25$

There is a good article on this subject on www.raptortechnique.com

`3D

My Feedback: (1)

The seting will also depend on the fuel type you are using.

With cool power 15% 1 turn should be a good starting point, I wound up at 3/4.

Wildcat fuel 15%, was a little richer..about 1 1/2 turn to start .then fine tune.

rough, blubber and a lot of smoke means too rich.

A quick cut out on throttle up usually means to lean.

I wouldn't suggest the barrel thing...it might decide to take off and chop your head off!!!!..or hands, arms...ETC....none of which would be pretty.

taildraggerdave

My Feedback: (1)

Thanks for the info. I'll screw in the needles tonight and find out how many turns out they are. Just to compare.
Regarding the barrel, I have a very short set of training gear on the heli and I put my hand on top of the center "puck" and held it down forcefully the entire time. Still not entirely safe, for sure. I have a heat gun on my service truck. I'll give that a try also.

Spaceman Spiff

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Maybe its my muffler,different engine, different altitude.... but mine ended up around 3 turns out for main, and 1.5 turns out for idle. TT39, mavrikk muffler, cool power 30%

geoff_nwt

hi there
there is a product called a head loader
two balls similar to the ones on training under carriage
they have a fixing bar on them and you take off you main blades and bolt on the head loader to you heli they load up your head like the main blades do but allow you to get in closer to set up ye engine ect ect

good luck
Geoff

`3D

My Feedback: (1)

30% requires a richer mixture

flyingjmerritt

My Feedback: (3)

whitch part on tower hobbies is the IR thermometer at?
engines? feild equipment?
i would like to get one of these also what is the temp range for a os 32 sx-h engine?

Kovedawg

Wow, the barrel idea actually doesnt seem too bad if you could just stick a 2X4 or something over the skiis to hold it there, or even a clamp. Thats probably alot safer than my method. I have mind on my training gear, and I just belly crawl up to it and tweak the needles with one hand and hold the tail boom in the other with the blades spinning a foot over my head. Mama always said I wasnt the sharpest tool in the shed. Heheh, anyhow, it brings me to a question of my own. I was having trouble getting my engine to support an air load at throttle. At idle it would run very smooth, and would be quiet responcive to half throttle, but once I lifted off it would only stay in the air a few seconds and then bogg down until I went to below half again. I tweaked the high speed needle until it was turned all the way in, if I tried to take it out even an 1/8 turn it would start to get very rich and die. I then tweaked the low speed a little until it ran a little higher at idle and that let me back the high speed off a bit and I was able to get it flying. But the engine still doesnt seem to be running its full power curve. Any suggestions? Oh yeah, iv got one of those IF temp gauges, but I havnt used it yet. Anyone know a good cool temp for a Webra 35?

`3D

My Feedback: (1)

Sounds like maybe your pitch curve is to great...try reducing the % pitch in 3 & 4 of the pitch curve.

Stanley makes a IR temp for about $80 +-

My webra 35 ran at 3/4 needle with cool power 15%

Raptor^Norway

What is the ideal temperature for the engine? And where is it measured? (Beacuse the temerature will be diffrent on the head/cylinder/crank-case) I guess the best place to measure is the head. And please, if you know the temperature in centigrades it is really helpful Got a IR-gun at work, so I figured i could try it one day

da_man

My Feedback: (30)

Did anyone say it could be the glow plug or bad fuel. Do you also have a pitch gauge?

If you return your engine to factory settings, get a new plug, new fuel, new lines, clean filters and run it at 1700 rpms and if you can't get it to run continously then it is an engine problem.

S1Pitts

My Feedback: (4)

Does anybody use a run-up stand anymore ?
I have one that securely fastens the heli approx. 5 ft from the ground allowing me to run from idle to full throttle -- pos/neg pitch curves . It is great for setting thr/pitch relationships & with a radio that provides multiple pitch points you can get a fairly constant head speed without a gv-1. Each time I rebuild or have a new heli it goes on the stand for a tweaking. A few hrs spent there & I have no suprises at the field. Would have to say it's my most valueable tool.
Ken

Furyflyer2

My Feedback: (117)

A run-up stand may not simulate actual flying conditions and IMO can't provide a accurate summation of engine tune, that's why nobody using them. The BEST method is flying it.

ronh

I had trouble getting my engine to run smooth. It was missing and rough. It turned out to be a loose muffler ! One screw had come a little loose. The tank back pressure was being lost, causing the engine to run lean.

iflynething

Ok..........i didn't want to read everything in these forums about mixture, I WILL most certainly get either a Venture or a Rappy 30 V.2 (that is later in life when I actually have the money (I'm ONLY 14 (No Job Yet))). But, how DO you set the fuel mixture on the helis. I mean I don't know much about them right now. But it seems to me that with all that rotor spinning on top, you wouldn't be able to get under them to set the mixture. Thanks for any help that you may have. Any site about this subject, any other forum that you have seen that answers my quesiton, or you can just tell me yourself. Thanks Very Much. Just wanting to get as much info on heli set up, anything that I can before I actually get on in the very near future.

Michael Carr
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AIM & Yahoo! Screename: xp3viper

"Why drive when you can fly?"
"That plane needs to be set free, give it freedom. If it doesnt' come back to you, then you should've checked your battery."
"Taking off is the second greastest thrill known to man; LANDING is the first!!!!!"
"Those are my principles, if you don't like them, I have more!!!!!!"

iflynething

I am thinking that you just set the needle on the ground and then fly, and if the mixture isn't right then you would bring it back down and keep resetting until you got the right mixture.........

cootertwo

taildraggerdave, just remember that with the TT39, the LOW needle is the main needle, at least up to about 3/4 throttle. This engine adjusts totally different from any plank engine I've ever had. Once I got used to how it adjusts, I like it.[8D]

taildraggerdave

My Feedback: (1)

I'm finding that out lately..........
Thanks