Guys.... need some help with a couple small problems that Ihave just been hand flying out but now I'll take the time to sort out at home.

Bobcat Composite - JR 9303 - flap/crow setup as per BVM manual (Chad's 9303adaptation from the 10x instructions) Matchbox on the flaps. Two problems:

1) Ihave the deployment on a 2 sec delay, the right flap goes down slightly faster than the left resulting in a hard left bank followed by stabilization when all is down. How can Isynch up their deployment? (Lower delay settings accentuate the effect instead of minimizing)

2) For the life of me, Ican't get the "take off" flap setting symetrical. I run out of throw on the match box trying to get them matched. Ihave recentered the servos and installed the arms in the BV prescribed way. (servo arm straight in line with load on full flap, etc.)

Thanks in advance.

Smitty

For problem (2) the easiest way I have found is to mechanically set up the flaps in the take off position. It is much easier to limit the throws at the end points than in the middle as you have more adjustment available in the TX at the ends. I never could match up the take off positions electronically.

Smitty

On the BC the flap width/horn to hinge position can vary, this will give a mechanical speed difference. If you have two channels available that would be better. If not you need to move the horn position. This might also point to problem 2. Are the pushrods the same length?
I always set the TO position with the mid switch position and no sub trim, then you can set each end point.

Hope that helps

Dave Wilshere

Yes, the pushrods are the same length. Idon't have an extra channel and I don't really want to move the horns so: is there a methodical way to go about lengthening or shortening the pushrods to attain the desireed result?

If you are using the same servos, eg JR591, then you need to ensure the pushrod is connected to the same hole on the arm. ie the distance out from centre is the same. You probably have this right already. I would slow down the flaps to the max, to give you time to see the deployment. I think the flap menu gives 2 sec max? but you could try the servo slow function and see if that makes it slower.
Then you can look for where the difference occurs.
I agree with dave, centre the servos in sub trim, match the end points, set the flaps to half down position, (reposition the servo arms to achieve this with no sub trim). Centre everything on the match box. Try the system and see what happens. Hopefully this should give you a good starting point to move on from.

Good luck

Why don't you use a matchbox???????????????????????????????




ENT

Read the second line of the first post!!!!!!!!!!!!!!!!!!!!!!

Open mouth, insert foot

Why don't you read the thread???????????????????

Smitty

The first part of the travel will be fast, last part slow. In reverse...going up the first part slow and second fast, this is presuming std arm position set up, with the arm near vertical in the flaps up position. Basically with the servo on it's side and arm between 5 to and 5 past the hour is fastest, between quarter to and ten to the hour and ten past, to quarter past the hour is slowest.
Slow things right down as recommended and see which one is slowest going down, I worry more about the total down time from flaps up to full flap as this could cause a problem slowing down to land, if you have to accept something then the take off position, to flaps up is least important, as you are accelerating and aileron control is good.
On this servo move the arm one spline forwards away from the surface and lengthen the rod, this if my brain is working should speed up the down time.
Then play with the slow speed to find the best set up. make sure you have strong servos that can resist the airflow trying to blow the flaps up.

Dave Wilshere

If you did flight condition deployments, Ie, 15eg flap, 45deg flaps, gear extend while in a banking turn it will all be a mute point concerning their speed to deploy.


I find it strange that a $100 matchbox is less desirable for me, in which I have removed from flaps in a CompB, KC, and Viperjet models in favor of a $10 one of these. (EXPERT is private label JR)

http://www.horizonhobby.com/Products...ProdID=EXRA325

I have found servo reversers to be unreliable and will not use them. The centering feature on my Expert frequently went out of adjustment. A Matchbox is probably much better, but I would rather reverse a servo or better yet use two channels if I can.

Joe

Just curious,
what servo's are you using? I have my flaps set up on my Super Bandit without a Matchbox, just into a Powerbox, but no adjustment. I used the servo speed function to slow them down when they deploy, and they come down at the exact time and finish at the exact time. I am using JR2721's on the flaps, same servo's on the flaps on my Kingcat, Razor, and Raptor, and they ALL work perfectly without a matchbox.
I try to always pair my servo's as closely as possible so that I don't HAVE to have a matchbox or if I do, it's work is minimal. I've never had a problem with JR servo's, the only time I've ever had bad luck trying to match servo's was on the odd sport plane I've owned with Hitec servo's. Hitec says just match them with the programmer, but I don't know why they can't make relatively accurate servo's to begin with

Actually, LGM, I have never had this issue either, now you mention it. I prefer to stick with JR servos, had some poor quality 'other' brands in the past. [:-]
This is an interesting one.

For you two guys , I use the Jr servos with the matchbox in my planes without any problems, maybe this
could be a servo problem, I don't really know. That I did
not finish reading the thread, that's my fault. But that doesn't give you any right to jump
on a person trying to help another with some advise. I think I made my point very clear. If you can not make a mistake
then , sorry for you.


ENT

I only use JR, but this can happen with linkage differences. For sure Hitec servos are a source of many problems.

Dave W

Some great info. Servos are 8411's. Idid not build/rig this - there is something asymetrical somewhere that is the culprit. Inow just have to find time to deal with it. Iwill post my action and the results. Thanks for the great advice.

I had a problem like this that I was able to electronically compensate for on different channels and different servo slow speeds on my 12x and BARF.

The culprit? If you see the image below (it just happens to be an 8411) the servo arms from JR can be very close looking from one to the other if you aren't careful at matching them. One servo arm will be different than the adjacent arm, eg.

My dumb arse was off by one hole and finally (after hours, at the field) pulled out the servos and saw my mistake.

I have no excuse, I built and put mine together. Flaps can be a pain in the butt...[:@]

Raf

RAV, great point, I'll check out the arms

c/f..... Itried a reversing Y instead of matchbox..... jitters like crazy and makes other control surfaces jump also.... Idon't trust it.
Ihave about 75 flights on this plane in this condition - deploy in a bank, etc. Ijust would like to take the time now to make it work like it is supposed to work.

ENT, no harm but Ithink people "jumped" on you because of your number of ???????????????????????????????????????'s

Hi, Smitty, Thaks for your words, but, I was just trying to give my humble opinion, since
i have this setup as I posted and has not given me any trouble. BUT, what Ravill says makes sense
regarding each servo. It's not the number of ???, but the remarks made. I'm a professional and as such
I do not make regards against anyone, but only constructive ones when I can.

Thanks;

ENT

RAV!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!

slow wing.....fast wing</p>

By the looks of your pictures I see you found your problem.

MACE

Yup, new arms installed..... travel time matches now. Ok, where do Istart to get it matched up the best? Subtrim is at 0, trim 0...... Iam going to clear the matchbox programming, anyone have a step by step recommendation?

A general rule of thumb is to set it all up mechanically...

Use your radio to program any end points and travel as a last resort. Make sure that with all travel at 100%, endpoints etc. that you have your arms on the same spline as the other servo. Everything must match as physically close as possible then go to your radio and match box for anything else. I would try a mechanical setup first then see where that gets you. Your servo arm positions will make a huge difference on endpoint adjustments and how close the match is during travel.

MACE

Yup, I agree with mace, I would go for half flap as servo centre, and work from there. You then have end point adjustment for the up and the full flap positions using the matchbox.
These should be VERY close to each other if your mechanical setup is good. You may even get it all done on the Tx without needing to go to the matchbox at all.
Good luck and enjoy the new smmmooooottthhh flap deployment.