8411 conversion to SA

vicenterc at comcast.net vicenterc at comcast.net
Thu Jul 29 13:17:20 AKDT 2004


Troy:
Thanks for taking the time and give us a very nice and detailed respond.  I need to start at some place so I ordered the new gears to eliminate any slope in my servos.  I guess that that could be considered step number one.  
Now, I need help to do the step #2,etc, unless you move to KC.  Looks like you have a good experience setting up your planes in the last few years.  Can you give us a compiled version in this opinion group?  This could be an important document.  I know that this process have been discussed many times for particular problems but there is not a good guide for pattern planes in one document (I know that there is one in Horizon Hobbies web site directed to IMAC planes) that I am aware.
OK.  Keep doing a good job. Thanks,
Vicente Bortone 

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Vicente,
I can feel when the servo gears are worn and also when the pots are worn. I'm not the natural pilot that some of the guys are....I work very hard at it. I become very "in Tune" with my model and I can tell when something changes. Yes Digital servos will compensate for worn pots better than analog servos because of the way they find center. Same thing with worn or sloppy gear trains. I said compensate better...but the problem still remains. In a really good setup I believe anyone can feel it.
Where I find the biggest problem in my flying with worn pots or gears in in loop tracking. I learned a little last year from an expert in pattern model trimming. I found that my models while they flew well didn't loop track for beans. I had a model that once we got done with it.....I could set the power at about 1/3 and pull or push tight I mean tight square corners....As in pull the wings off it square corners for about 3-5mins without ever touching the ailerons, rudder or throttle....and the model without any wind would stay in the exact same spot! I thought we were going to pull the wings off it....
You may think I'm crazy and that it is not possible but we did it. Since then I have repeated the same thing with about 4 other models. If the wings were level the model would pull the corner perfectly straight every time. When the servos especially on the ailerons get worn you CAN"T do this type of thing. In a corner the ailerons are forced by flight loads and they are required to hold their position. A weak servo will blow back, and a servo with sloppy or worn gears will move some amount before the servo begins to hold its position. In this scenario you are getting a "flapperon" effect. Inside corner will result in the ailerons raising slightly before the servo pushes back and holds the position. The ideal situation for the air foil and the model is to not have the ailerons move at all....but in reality things are flexing and twisting all the time. 
So you say well the slop is the same in both servos so they flex the same amount......is it really the exact same slop on both sides? How can you tell its the same? Any difference in the two sides will change the shape the of the wing and cause more lift on one side vs. the other.....When this happens you can't pull or push a straight corner. The reason is one side will make more lift than the other.
Next problem with sloppy gears in turbulence....If the gear trains are loose in turbulence the model will not lock on. The pilot may say man it bumpy up there....In reality the model will sit still better if the ailerons are not allowed to move that 1/8th to 1/4 degree. I proven it with my models.
I hear from pilots all the time that "I'm not good enough to feel that little difference" My answer to them is your model is not setup well enough to allow you to feel it. I'm not saying that your setup is not good...I'm just saying if you can't feel the difference in new vs. sloppy gear trains your set needs to be better than it is.
In the last 2 years I really have been a student of how bad my model setups were, and how much better they can get. As a result my quality of flying has gotten better and better in the last couple years. It still needs to be better to reach the goals I have set for myself. However without properly trimmed models I would never had achieved the small amount of success in the last 2 years that I have.
Trimming is a thing that is only as good as your level of expectation. Once you feel one that it is correctly setup and trimmed all lesser setups will feel poor to you. If you have never tasted a Filet Minot then you might think that Burger King has the best Beef around. This is not being stuck up or arrogant...Its a fact. Grab up the average sport fliers Tiger 2....and you will be able to tell the linkage is sloppy or the servos are weak....or the thrustline is off. The reason is you know in your head it can be better than it is. Same thing with pattern models. Until you fly a really well trimmed model you have no idea of how much better it can be. Many take the "That's about Right" approach and are sadly happy with the result they got. As your knowledge grows so does your expectations.
In the past couple years I have been lucky enough to fly lots of models. Both in helping other pilots trim their models, and my own models. I can say this almost any design out there can do the sequences, and any design out there can be setup to fly them very well. Attention to detail, and the knowledge that the model can get better is a start. Then the expectation the models needs to be better than it is will drive you to excellence. 
If your setup can't tell the difference between a new tight servo and a sloppy one.... then let us work on your setup so you can "Feel the Difference." The difference is there but other issues and problems in a setup will mask it. We spent lots of money on precision digital servos, stiff CF pushrods, slop free ball bear clevis links, Laser pointers to set control throws to 1/10th of a degree and yet many don't pay attention to the basics of the model setup. We pay lots of money for precision equipment like 1024PCM that has resolution like nothing we have seen in the model industry since the beginning and then we set our Dual rates at 50% travel and only use 1/2 of the electronic resolution of the TX, and servo.
Back in the old days before I was even flying pattern, the radios didn't allow for a quick fix of this or that, and the pilots had to be good with the sticks or had to know how to make the model setup correct. I'm not saying that I wish the old days were here...but Trim work is an art form. There are very few artists left...Most pattern pilots think the model is trimmed if it doesn't have any coupling with rudder. Well there is a ton more to model setup and trim than just setting up a Prog Mix that gives X% elevator when the rudder is deflected.
Please don't anyone take offense when I say the above.....I'm not telling you your skills at model setup are for crap....I'm just telling you that your model can be better than it is. To me this was an eye opening experience and I really started to feel the differences. 
The best advice I can give to someone that is struggling with pattern or with flying a certain maneuver is make you model fly better and the work load on you the pilot will be much less. WHEN the model is doing the work...the rest becomes much easier. Our models are tools to do the job. We expect laser type precision at times, and yet some guys show up with a chainsaw. Yes both will cut the thing that needs cut....its just a matter of the end results.
TN
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