5955 Stock Servo Arms

[F3AFlyer7]

Is it necessary to use aluminum arms on the Hitec 5955's instead of the stock nylon servo arms that come with the servos?? The arms it comes with are quite thick and feel like they should be sufficient, but I'm not sure if aluminum would give me any advantages. Anyone have any advice?

[F3AFlyer7]

bump

[JoeAirPort]

I always toss them. They are too thick for a clevis and if I'm using a ball end I use aluminum. I guess you could use them depending on the size of the plane.

[TheTank]

100$ servo, you might as well spend the $8 for a proper arm. I like to use ball links, and the load on the plastic arm will cause it to twist under load. Plus, you take the chance of the metal output gear stripping the teeth on the plastic servo arm. Just my .02.

[F3AFlyer7]

Sounds good to me thanks guys. Any suggestions on good aluminum arms?

[bryson]

Swb Or Airwild Are Both Great Arms!!

[JoeAirPort]

	Quote: Originally Posted by F3AFlyer7
	Sounds good to me thanks guys. Any suggestions on good aluminum arms?

These are my fav:
http://www.swbmfg.com/

[YaKs are BeSt]

I like the Airwild 1.25 and 1.5'' the best, But like SWB the best when using a double for a pull pull.

The airwild ride real low so there aint any twisting, and they arnt wuite as heavy, or expensive.

[JoeAirPort]

Yeah but the Airwild being so low can cause problems too, like the push rods rub on the plane.

[3dubya]

	Quote: Originally Posted by JoeAirPort
	Yeah but the Airwild being so low can cause problems too, like the push rods rub on the plane.

The best three letters SWB.

[GilesTxStyle]

Hello Scott,

This is 3 months down the road from your posting but its "fresh" for me tonight. If you are infact an F3A flyer, then I would think that you are talking control surface movements of 10 - 13% both ways, perhaps on Rudder you might go as high as 17 or 18% but with such incrememtal movements, I think the servo arms that come with the servos would do a fine job.

If you were flying 3D and a 50% Yak which weighed in at 45 lbs, then loading on the control surfaces becomes a totally different issue as well as control surface movements in the 35 to 45% range. These need all the help they can get.

Personally, I like the full circle control horns, that allow me to drill my own holes in them. Back before Scott( SWB) and Airwild were making aluminum arms we used the Circle horns with plywood extensions attached them! Creativity was the name of the game. I remember the first peek inside Ron Chidney's Tiger Tail, here were Proline/Durham KPS-11 Servos very linear.

Anyway, JMHO and thanks for the post it got my attention!

GilesTXStyle

[KrisW]

I've used the thin stock HiTec arms on the 5955 without any problems whatsoever. They are very similar to the DuBro HD composite arms that I have been using for ages.

The ONLY advantage that aluminum arms impart over the stock arms is that they look cool. Mechanically speaking, there is no advantage to the aluminum arms unless you are stupid enough to hang a ball link 1/4" off the arm, in which case you are really whacking out both your geometry and adversely loading the servos mounting pads and bearings, and need to have your head examined anyway.

For 99% of applications out there, especially if the control surface and servo output shaft pivot on the same plane (servo laying on it's side for ailerons and elevators), a simple clevis on the stock thin composite arm is as good as any ball link setup you can buy. I've done it that way for many years. . never had a failure. . and in a crash, the arm will probably break, saving the servo somewhat. I'm sitting here looking at the wings for my 3M Composite-Arf Extra. .DuBro composite arms on 5955's. . with clevises .. and the arms and linkages have been in the plane for 3 years. . just swapped in 5955's in place of the older 5945's about 9 months ago. . never a whimper or problem.

I, personally, would not bother wasting money on trick aluminum arms unless you are using bal links and need to bolt the links to the arms (since you can't. . ever.. use a clevis with an aluminum arm anyway).

Now, if you want to use the aluminum arms (for whatever reason) either use the SWB arms, and put the ball link on the BOTTOM (servo side) of the arm to prevent rocking the servo on it's mounts too much, or buy the Air Wild arms and put the ball link on either side (though the bottom is recommended). both are bullet proof setups .. but IMO they are totally unnecessary.

[DKjens]

I have 5955 servoes in my 43% Giles, 2 per ail half, 1 per elev half, 2 on rudder. I used the arms that came with the servos on ail and elev and I have no problems. This Giles is set up for IMAC style flying, but it does have about 35-40deg on ail.

If the servoes are used in a 3D set up, aluminum arms may be the ticket. If used in a less radical set up, the stock arms are fine.