SWB's
 

Stupid me, I just got my 1.25" SWB arms and I noticed something that I didn't think about. I was planning on faving the servo arms point up instead of down. But there is a clearance issue. I know I've seen people with their servo arms up and I am now wondering if they got the 1" arms or if they lowered the servo in the fuse. Anyone else run into this problem? As far as the mechanical advantage is there over the arm up or down? I thought that with it up it would be better.

Any thoughts ??????

RE: SWB's
 

I ran into the same issue. I am running them down and see no problem. I am not a eng. so I can't tell you if there is any disadvantage. I have see this posted in the past , others have said it ok. Call W.H. , they will know for sure.
ASTRO

RE: SWB's
 

I have my servo arms pointing down all the time. Be sure you have solid servos with a 1/5" arm, that's a lot of mechanical advantage against the gears.

TF

RE: SWB's
 

OK. I'll do it with them down for now. Got 5945's and an 8611 so I think the oz's are ok.

RE: SWB's
 

The mechanical advantage IS better if they're pointed up. I can send you a program to compute the forces if you want it.

I did this...

... I took the SWB arms and a moto-tool cut-off wheel and cut off the last hole. It gives you between 1" and 1 1/4". Mounted upright, I get almost 40 degrees of travel, which is plenty for me to harrier, do walls and parachutes, wicked tumbles, super flat inverted and upright spins, etc etc etc.

Just my .02.

RE: SWB's
 

Do you have a picture of the arms after they were trimmed???

RE: SWB's
 

It really doesn't matter which way the arms point as long as you maintain good distance geometry with all the linkages.

I also trimmed a small amount off the top of my JR aluminum arms to clear the elevators. Just grind down the end until it clears. One individual had the innovative idea of installing the elevator servos in the rudder servo openings, and as long as the angles aren't to great between the arm and the elevator horns, it should work well.

RE: SWB's
 

of those of you who used SWBs or Hanger 9s aluminum servo arms, on the JR 8611s, did you
have problems with the servo arms fitting correctly on the output shafts of the JR 8611s? I
bought Hanger 9s first.. they did not fit... reading about SWBs here, I ordered some from them,
and only one of the five I ordered from SWB fit on the servos. Did anyone else have this problem?
I put in a call to SWB, and left a message. Will see what they have to say if anything.



Sitting here hating the thought of Plastic servo arms on my WH Edge 540.

Gerald

RE: SWB's
 

From what I hear is that the 8611's aren't all the same size, SWB makes the new double-loc arms for that reason.....to take out the inconsistencies.

RE: SWB's
 

i used the same arm for my 8611 heres a pik

RE: SWB's
 

Thats the same arm that I got for my rudder too...SWB also makes them in the half-arm version.

RE: SWB's
 

No, I don't have a picture... sorry.

The only problem with mounting the arms inverted is this...

... the angular load on the servo motor is slightly more, probably not enough to worry about with an 8611. However, the linear load on the linkage and output shaft bearings is greater (by about 10%), especially when deflecting the elevators down. This once again is probably nothing to worry about, but it's the way I went.

RE: SWB's
 

Rockyaged,

What do you mean by not fitting? If you are referring to what appears to be an arm that is so closely machined that it requires almost a press fit to go onto the shaft, that is the way it's supposed to be. If you have a correct fitting servo arm, it will generally require that the retaining screw be used to set the arm onto the shaft.

If the arms are loose, then you have another story altogether. At that point, call SWB and see if you can return the loose arms for a set of the bolt down arms.

In any case, you do not want to use a servo arm that fits sloppy or loose on the servo output shaft. two things happen. You will soon have a servo that has a worn out or broken gear train, and you are inviting flutter.

RE: SWB's
 

Silversurfer..
Thank you for your comments, and I totally agree. I did try to
press fit them to the servos, but came very close to stripping the
head of the servo screw which I took to mean that the fit was not
going to be made. I'll keep the servo arms as they fit nicely on
my throttle and choke servos. I have since made another order to
SWB for the Double Lock servo arms.
For you that are familiar with RC Blimp Productions, I am the
Father of the man behind that manufacturer of Carbon Fiber
accessories. This evening he gave me the proto-type tailwheel
assembly designed for the 25% to 28% aircraft. It will be going on
My WH Edge 540. If the tailgear passes the tests, it will save
you close to a full ounce at the tail of the airplane. I was an Aircraft
weight and balance technician in the USAF for 24 years. Please believe
me when I say that will "help" cure the tail heaviness of a DA 50R equiped
WH airplane. That it matches the Carbon Fiber Landing gear up front is
a personal opinion of mine. When the testing is complete, I will post the
results here in this forum and in the Giant Scale main forum.

Gerald

RE: SWB's
 

I'm in the same boat, I ordered the 1.25" SWB's, and they are STILL too long when I try to face the arm up.(hits the horizontal stab).


TW

RE: SWB's
 

I've decided to just leave them down for now. We'll see how it does and I'm sure that it will be alright. Looks like I'll have my Edge 99.9% done this afternoon. Waiting on a loaded battery tester and two more ball-link's for my pull-pull. LHS ran out on me...[:@] Figures.

RE: SWB's
 

Just curious if anyone is going with Hitec servos, they look to come with the metal arms. And if so, is anyone replacing those arms withthe SWB?

RE: SWB's
 

I am using 5945s, 8611 for the rudder. The blue arms that some with the servos are 3/4" I think. I wanted more leverage, but might be good for you. I don't think that the blue arms are threaded for 4-40 as the SWB arms are. I am using ball-links on my arms as well. If you use the sullivan hardware that Tom supplies in the kit the blue arms will probably work as long as you don't try and get huge throws out of them. Its all about torque.

RE: SWB's
 

Hitec's blue arms are 7/8 inch from the center hole to the outermost hole. I think they would be fine if you want to fly precision with the WH planes but for 3D throws they don't quite cut it.