ELOSSAM
Senior Member
Posts: 146
Loc: MADRID, SPAIN
Reg: 11-19-01
|
 01-17-03 10:48 PM - Post#14768
Does anyone know if the the use of larger tail rotor blades can help to reduce the tail to shack?
Elossam
|
Billme
Senior Member
Posts: 198
Loc: MS
Reg: 03-26-01
|
01-18-03 01:34 AM - Post#14770
In response to ELOSSAM
Do you run flexable thin plastic blades ? What blades do you run now?
Every japan design that I've seen, the razor thin tail blades that flex, will vibrate ...I use NHP's carbon blades on the tail, due to its fat profile....
Bill
|
ELOSSAM
Senior Member
Posts: 146
Loc: MADRID, SPAIN
Reg: 11-19-01
|
01-18-03 08:50 PM - Post#14788
In response to Billme
No. Bill, I substitute the horrible original ones the second day and put in place a pair of SAB-X-CEL carbon fiber ones (same size).
Somewher I read that in case of tail shakes diferent tail blade size could help but can remembers if I should try with bigger gones first. I think so, at least if they doesnt work I can cut them 
Elossam
|
nsacco
Senior Member
Posts: 453
Loc: Raleigh, NC, USA
Reg: 01-10-01
|
01-18-03 11:36 PM - Post#14798
In response to ELOSSAM
When I was experimenting with my Xcell Gasser, I used 700mm NHP carbon blades and 95mm NHP tail blades. I liked the setup, but you do lose a little on the tail. Speed up gears I've heard work ok, but never used them. For my style of flying (nothing radical) I simply use the Xcell standard blades (plastic 105mm) on the tail.
Just like main blades and control response, it varies with rpm. Guys I know liked to run mains @ 1800rpm on the gassers, but I prefer 1700. Depends what you want to try and do. Let's face it a gasser is a lot heavier than a nitro heli of the same size. High rpms will indeed make it snappier, but at the sacrifice of longevity.
Keep an eye out for tail blade strikes which could bend and/or twist the tail blade axle contributing to vibs due to out of round. Tail blades should always be loose enough to swivel with light finger pressure. But no so lose as to flop around.
| Happy Flying!
It's not how much it costs, it's how much you can afford! |
|
Billme
Senior Member
Posts: 198
Loc: MS
Reg: 03-26-01
|
01-19-03 01:18 AM - Post#14803
In response to nsacco
Elossam ,
Just what kind of shake do you have on the tail...Is it side to side, or up and down?...Do the fins buzz too?
nsacco
I like 1650 rpm on my Xcell....I have the 33inch boom, so I run 720 Vblades with the 105 nhps..It feels lighter since the disk loading has been reduced...I'm not a stick banger, so that doesn't matter to much to me...It is fun making these machines perform though...
Enjoy reading your post...:)
Regards,
Bill
|
nsacco
Senior Member
Posts: 453
Loc: Raleigh, NC, USA
Reg: 01-10-01
|
01-19-03 12:36 PM - Post#14821
In response to Billme
When I ran the 700mm blades, I could run a bit slower on the mains and noticed a lighter feel. Now, flying 680 NHP at 1700, I definately have a slower climber and thus a heavier feel. Most folks end up trying to make the gasser fly like a nitro and to some extent they do it with lots of head speed. Personally I don't prefer that approach.
Occasional flips, inverted, loops and such do very well but I use the heli a lot for gound maneuvering, nose in and such.
What boom are you using? Did you wind up making a longer drive system (e.g., arrow shaft) also? Are you running a pod & boom or scale ship?
| Happy Flying!
It's not how much it costs, it's how much you can afford! |
|
Billme
Senior Member
Posts: 198
Loc: MS
Reg: 03-26-01
|
01-19-03 05:41 PM - Post#14845
In response to nsacco
Its my 3D machine..Pod, and boom:)
I run the Fury Ex boom, and drive....700's are still to small, although they are the minimum blade to run for my setup...Running the 680s , there is not enough pitch to load the engine...I can run the 680s with a straight fai setup, but it still flys heavy...Lowering the disk loading really makes a big difference..Also, I think like Mike Mas on lower rpm, it allows more power to be used for the manuver..
Bill
|
ELOSSAM
Senior Member
Posts: 146
Loc: MADRID, SPAIN
Reg: 11-19-01
|
01-19-03 08:48 PM - Post#14854
In response to Billme
Most of shakes I suffered were side to side but reducing gain solves it nothing. I discovered this weekend the tail blades holder were not perfectly straight so I changed it and I works better but still have some. I use a long tail due to the long blades I use (81cm) and so it´s possible I can note shakes that a shorter tail boom will not show.
|
nsacco
Senior Member
Posts: 453
Loc: Raleigh, NC, USA
Reg: 01-10-01
|
01-19-03 08:58 PM - Post#14855
In response to Billme
Sounds nice, Bill. Perhaps this summer I'll configure mine with longer blades etc. I agree that the 680s just don't load the G-23 as it should be loaded. I liked the way the heli felt with 700's. Having flown an Intrepid with 710's was much lighter feel also.
| Happy Flying!
It's not how much it costs, it's how much you can afford! |
|
Billme
Senior Member
Posts: 198
Loc: MS
Reg: 03-26-01
|
01-20-03 12:52 AM - Post#14864
In response to ELOSSAM
Elossam,
If you have reduced the gain, and its still doing it...I would think your lowend is still rich..Have you tried leaning the lowend a bit...Sometimes it not enough load....Simply add some hover pitch...If it stops, ok, if it don't, your still rich...Where are you on the needles? BTW, you would see it on a short boom too.....
Bill
|
ELOSSAM
Senior Member
Posts: 146
Loc: MADRID, SPAIN
Reg: 11-19-01
|
01-20-03 11:07 PM - Post#14881
In response to Billme
Hi Bill, I arrived at a point where the heli demands 1+1/2 turn on high (and never less) and I´m going about 1+1/4 on L. At this point I can check a beauty brilliant black with no residues on the metallic disc of the plug but still have a nasty white tone on the ceramic. The engine is running at 190ºF after a fast flight and 220ºF after some minutes hovering. I´m afraid leaning the low end, I think I´m close to the limit you recommend not to go below. How long must I flight non stop at full thr to have a good colour plug reading?
Elossam
|
Billme
Senior Member
Posts: 198
Loc: MS
Reg: 03-26-01
|
01-21-03 12:53 AM - Post#14891
In response to ELOSSAM
Elossam
I know your running motorcycle oil....You are running way to lean...trust me, PUT your high at 1 1/8.....On the RC230, when you get to 1 1/4, your lean....You should be at 1 3/8's on the low....If you were running AMSoil, this situation wouldn't be that lean....I'm going by your plug color, and you have a tail shake:)
You want a tan brown on the Ceramic...Don't worry about the color on the metal part, it will get kinda black while idling with my setup...Its the ceramic part that is important...White is ok, if tan is on the other side of the ceramic....Otherwise all white is not good, to lean....
We have the 230 running at 150 degs in 90 deg weather over here this past summer..., so i know 190 to 220 is hot for that engine...That engine has the best cooling system availible....
This is where your tail shake is coming from....
Get the heli in a hover, and start riching the lowend till your tail smooths out....You may have to add some throttle if you lose rpm...Clean your plug or replace it before you start all this:)
Regards,
Bill
|
Billme
Senior Member
Posts: 198
Loc: MS
Reg: 03-26-01
|
01-21-03 01:09 AM - Post#14895
In response to Billme
Elossam
I know your thinking, Gosh, he tells me I'm running to lean, but he told me to lean more on the High....
I'm going to tell you something that most people don't understand about gasser carbs..
3/4's of your fuel flow is done with the lowend needle...You have 3 orfices that the lowend needle regulates...It has to be open more than the high needle which only regulates one...
This IS the reason I run the needles the way I do...
Now, think about those who run at 7/8s on the lowend...It makes me feel like someone is scraping their nails on a blackboard:)
Regards,
Bill Meador
|
cbergen
Member
Posts: 44
Loc: Fayetteville, GA USA
Reg: 03-18-01
|
01-21-03 09:29 AM - Post#14910
In response to Billme
The only way to run 7/8's on the low needle is to use more oil.<G>
I'm starting to think that some of the flyers who are curious to try to run your setup, Bill, are a little hesitant. So they try some kind of compromise with, unfortunately, less than successful results.
If someone wants to run the setup that Bill suggests, then by all means, go through the entire process that has been well documented by Bill. We get more calls from flyers who are having trouble with vibes and tail shakes and inconsistent engine runs, only to find out, after lengthy discussions, that they wanted to try Bill's setup with less oil, but were scared to go quite that far. In most cases, the suggestion to go back to 5 oz of oil and setting the needles as suggested by us, gets the heli back in the air with acceptable results.
It may well be, that some are missing the point that you have to work on your pitch and throttle curves to get the engine loaded, and are just lessening the oil and trying to get the heli to fly.
| Chris D. Bergen
Bergen R/C Helicopters |
|
Billme
Senior Member
Posts: 198
Loc: MS
Reg: 03-26-01
|
01-21-03 02:12 PM - Post#14915
In response to cbergen
Chris,
I couldn't have said it any better myself....Heck, I had one guy running 5 ounces trying to run my needle settings, hehe
Then, another running 100:1 on 7/8s !...You can't win!...:)
Regards,
Bill
|
Billme
Senior Member
Posts: 198
Loc: MS
Reg: 03-26-01
|
01-21-03 05:56 PM - Post#14928
In response to Billme
BTW,
Elossam has done a good job overcoming problems by himself, trying to run the setup...But, the difference, just like we found, is in the oil...So, I have to make adjustments for this, and he has done well....This is the reason I give minimums on needle movement to catch stiff like this, and he went by the rules:)...The clue, was the the tail shake, after he told me a white plug...
He can still run his oil, he just needs to richen the lowend, which will give a more tan on the plug, and should smooth out the tail....
Load is a hard thing to desribe as to how much they need, and not be there. Different blades, and lenghts are in play. This effects the gasser tremendously..
Regards,
Bill
|
ELOSSAM
Senior Member
Posts: 146
Loc: MADRID, SPAIN
Reg: 11-19-01
|
01-21-03 11:36 PM - Post#14952
In response to Billme
Thanks Bill and Chris
I will try again with your setup (and as many times as required).Thanks for your patience; I think I´m one of the worst pupil you ever had but thanks to you I´ve a better idea of how to treat these little demons.
It´s completly impossible to get AMSOIL here and I started using KLOTZ at a 2%. (VARIO recomends this oil for his Gassers with same engine)
Have no idea about the minimum % required with this oil, that´s the reason I want not to go below this amount.
For starting up the engine I must always hold the choke, pull two or three times till the engine gives any explosion and then
take the choke out and pull the starter one time to get it running. Doing it so I don´t need to use the choke any more and the
engine holds a very stable idle. I run this way either with 90 deg or 45deg weather. I suppose that confirm you I´m running to
lean on the lowend because if not I must be able to start the engine without choke like someone tolds you time ago in some
post (I remember that but can tell you when was it posted)
Is there any relation between the amount of fuell into the fatten bulb and the way (lean or rich) I´m running the engine?
Take care
Elossam
|
Billme
Senior Member
Posts: 198
Loc: MS
Reg: 03-26-01
|
01-22-03 11:35 PM - Post#15020
In response to ELOSSAM
Thanks Bill and Chris
I will try again with your setup (and as many times as required).Thanks for your patience; I think I´m one of the worst pupil you ever had but thanks to you I´ve a better idea >>of how to treat these little demons.
Your doing fine, it takes a little time to grasp.. Nothing beats hands on knowledge…
>>It´s completly impossible to get AMSOIL here and I started using KLOTZ at a 2%. (VARIO recomends this oil for his >>Gassers with same engine)
That’s in Spain…each importer has their own favorite oil.. Belray is what Vario USA likes to use if the customer has reserves about AMSoil…England likes Rock oil etc…
>>Have no idea about the minimum % required with this oil, >>that´s the reason I want not to go below this amount.
I have my own minimum when starting out with any oil other than AMSoil.
50:1 is a very good figure for most oils, unless implied…also, only use oils that are designed to go higher than 50:1 ..
Nevertheless, the amount you are running now, you should be ok, you just need to richen the lowend to get a better color with a smooth run…If you richen, and still get a white plug. You may be not running enough oil, get it?
This is the reason I get the engine running good, then after some running , look at the plug. Then add or subtrack the amount of oil….In my case, I work between 1.5 to 1.75 ounces to get the color right
>>For starting up the engine I must always hold the choke, pull two or three times till the engine gives any explosion and then
take the choke out and pull the starter one time to get it >>running.
I prime the bulb 10 times, and pull three times, without ever using the choke
>>Doing it so I don´t need to use the choke any more and the
engine holds a very stable idle. I run this way either with 90 deg or 45deg weather. I suppose that confirm you I´m running to
lean on the lowend because if not I must be able to start the engine without choke like someone tolds you time ago in some
>>post (I remember that but can tell you when was it posted)
I don’t think I understand what you saying…There is some point where you have to richen up when the weather takes a drastic change
>>Is there any relation between the amount of fuell into the >>fatten bulb and the way (lean or rich) I´m running the engine?
I guess you have seen this, otherwise you wouldn’t have mention it….Yes you can get to lean, which can mess up the metering system, which will screw up the pumping system when there is not enough flow thru the system as a whole..when you richen up, it should come back up unless the metering lever is set to high....
Regards,
Bill
|
ELOSSAM
Senior Member
Posts: 146
Loc: MADRID, SPAIN
Reg: 11-19-01
|
01-23-03 06:26 PM - Post#15041
In response to Billme
Hi Bill, I did a short flight today. The needles were setted 1.3/8L and 1.1/4 H. the heli flyes as with the old way the first 15 min then I tried to rich a litle more the lowend. Just after this new setup the engine started loosing a power all the range till a point where it was unable to hover and after refuelling the engine didn´t want to start again.(but there is no wet plug). I removed the plug and it showed a black color on the ceramic ( not perfect black but black in each case) The metallic ring shows also a fine black tone. What should I do now lean the High or the Low end?
Note it was running within the same temp range as with the old way
You show me the L needle can also modify the full range of the engine and not only at lower RPM. It can toast the ceramic too, then how will I know when a H needle adjust is neccesary?
Elossam
|
Billme
Senior Member
Posts: 198
Loc: MS
Reg: 03-26-01
|
01-23-03 10:30 PM - Post#15049
In response to ELOSSAM
Put the high needle at 1/1/8...You should be able to start out on the lowend with 1 3/8's .....Are you moving the throttle up, as you richen...If you just richen, and not move the throttle up, it will just bog more...Your butterfly should be open from about 35 to 45 %...Don't try to run this engine low rpms...
Do this, put your high at 1 1/8 , put your low at 1 3/8's, and just leave them there..Don't touch them any more for a while, and just adjust the rpm, and load on the engine, and see what happens....I know everyone that I have setup runs good there with my setup, so it may be the oil, and amount that is messing things up...
What gear ratio are you running? What blades, and lenght, and how much pitch? I don't remember:)
Bill
|
|
Attachment: 