RE: How much trim is to much?
 

The OPs problem was in the aileron trim, what would that tell you? 20 clicks is a bunch out of trim and he shouldn't have a lot of aileron movement left with that much radio trim. Before fly fly fly the problem should be located and corrected.

RE: How much trim is to much?
 

I use a straight edge on all surfaces to align them mechanically at zero trans. trim before flying. Maybe I obsess too much, but I rarely have to use more than a few clicks of trim(to allow for the CG variance and fuel load) from a 33% gasser to a trainer. Probably a carryover from the basic 4 channel days. I thought I was right uptown when I got my first radio with reversing switches.

RE: How much trim is to much?
 

Agreed. This problem MUST be corrected before the next flight or you risk the plane being in an attitude that it might not be able to get out of due to limited aileron control in the direction you need and then it will quickly become a pile of rubble.

RE: How much trim is to much?
 

Of course. With 20 clicks of trim, he has used a lot of travel in one direction which leaves a lot less of standard movement. It should, or should I say, must be mechanically adjusted out. No, don't just fly - fly - fly the thing, fix - fix fix it!!!

RE: How much trim is to much?
 

Ok, the OP said nothing about other problems with the airplane. So let's assume the plane flew just fine after landing, and after having put in 20 clicks of aileron trim (i.e. no control limitations). He now knows where the ailerons need to be. We could hypothesize for hours why.

The question was, should he go to the effort to mechanically correct the trim. Not required, and not a "MUST". How does the plane fly now? Do you feel you have enough aileron to turn in both directions? Do you run out of aileron in one direction at slow speed? Have you reached the trim limit? If he has no other noted problems, fixing it just for the sake of removing the electronic trim displacement so he can feel mechanically pure is pointless goal.

What if he has 20 more clicks of trim left? "...and then it will quickly become a pile of rubble" is extreme.

Kurt

RE: How much trim is to much?
 

I strongly disagree. It is of course an opinion but I believe a valid one.
I would like to see a setup that with 20 clicks of trim, with no altered trimresolution adjustments, that would not yield a drastic control limit in one direction. Come on Kurt. I think youknow better or at least you should.

RE: How much trim is to much?
 

Pamster,

But the OP didn't mention any drastic control limitations. I fly an indoor glider with the rudder trim max'd to the left. The controls are hot glued inside of an epp fuse. Do I need to fix it just for the sake of "fixing the trim." No. It flies fine as is.

If the OP landed and said "whew, I can barely turn left" maybe he should fix it. But he didn't. I like to question slippery slopes. Don't say 20 clicks of trim is too many because you think 20 is a big number. What about 10? or 5? Once again, I'll stick to my mantra: How does it fly? (see the other thread da rock!) See my complicated flow chart!

Kurt

RE: How much trim is to much?
 

He didn't mention any drastic control..... 20 clicks?

CGr.

RE: How much trim is to much?
 

Actually he did not state either way how the plane flew and has yet to post since the first post.
I am not familiar enough with indoor models and the power plants thereof to say about full left trim on rudder for the model to fly right. Though I would wonder how much right rudder throw you now have and would wonder about motor thrust angle. But again I may just need to be instructed about indoor flight before I can effectively comment on that.
But this is not an indoor plane, though he did not actually say, but 20 clicks from any radio I have ever owned, computerized or not, is a lot. And I would want to know what the problem is and how to correct it and feel this is what the OP wanted to know.
I understand what you are saying about how does the plane fly but if any of my planes, and I mean any, needed that much trim, there must be something wrong and I would fix it.

RE: How much trim is to much?
 

The OP also didn't say he is a beginner but this is a beginner question in a beginner forum.
So how does he know what to compare it to ? Being that the geometry of the linkage is off and the servo has more throw in one direction than the other. He may not know it and it's best to understand it and get in the habit of correcting it .
Come on.........anyone who has set up aileron throws so you have more up and less down on each surface knows to offset the servo arms so the servo moves more in one direction than the other. As stated many times in the thread, the servo throws are now limited in one direction because of all of the trim put in.
It will make a big difference when he moves into faster and larger planes so best to get in the habit of correcting it now.

RE: How much trim is to much?
 

The above question, taken from the original post, is should he remove the 20 clicks by making mechanical adjustments, and that's what we have been addressiing, not how much the 20 clicks have affected his control. We already know how much it would affect the performance because most of us have had to remove the electronic trim by using mechanical adjustments to zero out the sticks, which would include the trim. This means leaving the control surface where it is and then zero'ing out the mecahism so that the servo starts at zero with the trim accounted for.
CGr.

RE: How much trim is to much?
 

Until the problem/reason for the need of the trim is located there is no reason to do any adjustments. It could be something as simple as the wing not being installed at center? Perhaps a bad warp or the stab being installed incorrectly? At any club I have ever flown at there are usually several people that can check a plane to see what is wrong. Usually something like that would only take a quick glance to see the why of it. I don't recall ever having to add more then four clicks/beeps of trim in any of my planes but I spend a lot of time on a plane before it gets flown. I wouldn't worry about that and would fly fly fly the rest of the day but rest assured I will know why it required even that before I go home so I can correct it in the comfort of my shop. If I ever had to add that much trim in a plane I would find the problem and correct it before the plane ever flew again. I put too much time and money in a build to risk flying with a trim problem like that.
Then there is that time I flew a plane with a bad running engine and an RF glitch because the guys wanted to see the plane fly. That was an exciting 4 minutes but the loss of 6 months of my life. Never again.:eek:
By now I'm sure the OP thinks we are all a pack of Snarks and is afraid to post again!:D

RE: How much trim is to much?
 

My hope is that the OP is not embarrassed for what he may have found after a second look at his plane after reading the comments and decided not to post his findings.
HIs findings could help someone else reading this thread to solve a similar problem.
We have all made mistakes while in this hobby and hopefully learn from them.
Either way I hope he figured it out.

RE: How much trim is to much?
 

20 clicks of trim is a lot of aileron travel. I assume you are on the default setting of 4. Even on a trim setting of 1 that is still a lot of trim.
If the model is flying OK and not running out of aileron travel, there is no real problem. If you are only concerned with the transmitter trim setting not being zero and will not be correcting whatever is causing the aileron trim, then there is no point making mechanical adjustments as you will still end up with the same aileron setting. Obviously something is out of alignment, so if it was me i would want to find the problem and fix it. A correctly aligned model with minimal trim will fly much better.
You need to ensure the wing and stab are parallel in both axis. Also that the fin is at 90 degrees to the wing and stab and that the wing is not twisted. Get these correct and the model shouldn't need much trim to achieve hands off level flight. Once this is done then trimming the model completely is another ball game.
If you are happy with how the model flies and don't want to stuff around with all this, then forget about it and go fly and enjoy yourself.

Good luck.
Scott

RE: How much trim is to much?
 

If you're going to trouble shoot the reason your model took so much trim, remember an important thing. About the only thing that is powerful enough to require that much trim is the wing. Start by looking there.

RE: How much trim is to much?
 

This is true, except for if he never centered the control surfaces properly. That could easily account for 20 clicks of trim.

But, you are correct. I assumed that everything was together properly. But, you bring up a good point, as did Gene (Grey Beard and everyone else).

Assuming that all is correct, I would re-check centering of the control surfaces, and re-fly. If it still needs 20 clicks, well, I guess start over and do what's needed to get it right. I don't think I would accept 20 clicks as normal, though. That's just way to out there.

CGr.

RE: How much trim is to much?
 

Okay, here are some facts:
1. I am not a beginner, I posted this question to start a debate and get some info.
The Beginner forum is usually the most popular so you get a better debate.
DON'T EVER ASSUME THAT THE OP IS A BEGINNER IN THIS FORUM!
2. The plane is a World Models Mach II that has been rebuilt - wing and fuse, expect some problems.
3. The plane flies great now that it is trimmed.
4. I have not had a chance since Sunday to adjust it and I am going out today. I expect it will fly great.
5. It will get changed to where there is less than 5 clicks, -0- ain't reasonable.
If using Nyrods you can expect that much change from temperature expansion and contraction.
Some surfaces will need changing just due to speed, wind and style changes.

I have, and I hope others have, gleaned a lot of info from this thread.
I want to thank those that have contributed.

All have a Good Day,
KW_Counter

RE: How much trim is to much?
 

So this is your pastime ?

RE: How much trim is to much?
 

We are supposed to assume that the OP is a beginner, on account of this being the beginner forum. Asking questions that you already know the answer to is just a waste of everybody's time.

RE: How much trim is to much?
 

Only a beginner would use nyrods ! ;)
If you have 20 clicks of stretch in your nyrods...you have other issues!

RE: How much trim is to much?
 

I thought it was fun and I'm sure all the answers and debate gave some beginners a lot of information. Like don't ask a question!:D I was asked to join another site and I gave it a try but unlike RCU most of the people were too static, never debated anything and if you didn't post politely there feelings got hurt. Other then being able to post more photos and a lot faster the other site isn't much fun. Controversy and debate is more interesting. Much more fun then watching glue dry.

RE: How much trim is to much?
 

If this is what you do for kicks, then you need to get a life and stop wasting peoples time!! If you are after genuine advice, be up front and ask for it.

Also just because a model has been rebuilt there is no need to "expect" trim issues. Whether it is a new model or rebuilt after a crash or whatever, if it is built straight there will be no trim issues.

RE: How much trim is to much?
 

guys, whatever motivated any post or thread, they're going to be of value to someone somewhere. More someones get help when the responders share their knowledge and experience.

None of these threads are the property of anyone. OK, in fact they are. They're the property of everyone. It's up to us to make the property valuable.

This one has been quite good value. Any beginner with a modicrum of sense who reads through it will certainly be able to pick out good info throughout it and leave with a better understanding of the hobby.

RE: How much trim is to much?
 

Drac, you need to lighten up a bit. This IS a beginers forum, but anyone can ask questions for any reason. I manage this forum and allow pretty much anything to be discussed without sensorship except for when folks begin to get a tad bit testy. Take that advice and simply lighten up.

The information passed here will be helpful to someone. I use Sullivan rods and get absolutely great results from them. If you don't, perhaps you should look at your own setup.

If this thread goes the way it looks like it is going, I will simply lock it down... and most members know that I will do just that. So, keep it clean, keep it simple, and keep it on subject. If you have complaints, go report it. We will deal with it accordingly.

Consider yourself advised!!!

CGr.

RE: How much trim is to much?
 

Ok. But I wasn't the one who mentioned nyrods.