jonlowe

My Feedback: (12)

I know I'm going to get a lot of "you shouldn't do that", but here is my problem. Based on what Bob Pasterello did on mounting Hitec HS-55's directly to Hyde mounts for a very precise and light throttle servo arrangement, I started doing that last year. I was using Hyde mounts, both AR and ARI, on two different airplanes, both with OS 1.60s. The servos lasted the whole season, probably 150 flights on each airplane. This year, with two different airplanes, I began using Budd mounts with the same servo arrangement, again with OS 1.60s. The HS-55's are lasting maybe 30 flights, before pot wear starts the servo jittering at midrange. They never fail outright, so I can always land without incident. A waivering midrange is my indication the servo is going out. Is anyone else doing this with Budd mounts? Have you found a servo that lasts?

Here is a link to Bob's website that shows what I'm talking about.

http://www.rcaerobats.net/ThrottleServoHyde.jpg

Thanks.

Jon Lowe

DaveL322

Jon,

My Vivats were setup with the throttle and mixture servos on the Budd mount. 3421sa's, and they typically died from fuel soak (usually 200 flights or so). I think I did have one where a wire broke from fatigue. FWIW, my servos were mounted horizontally, so the dominant vibration would cause rotation between the pot/wiper, not "bouncing" (same idea as mounting aileron on their side, instead of vertically in the wing).

I suspect the issue you have is that any given plane / mount is going to have a "bad" resonance for a specific servo, and if you've happened on that, any change in the system is likely to result in an improvement.

Regards,

Dave Lockhart

jonlowe

My Feedback: (12)

Thanks Dave. I'm trying to picture the servos mounted on their side, and how you mounted them, but can't. Do you have a picture?

Jon

jetmech43

My Feedback: (9)

why dont you mount them in the standard place, Ive never had a failure

jonlowe

My Feedback: (12)

More precise, lighter, very short linkage, easy to adjust.

Jon

DaveL322

Jon,

I think a pic is attached. Basically, I drop the engine in place, and the bolts for the engine capture a piece of alum angle stock which has the servo mounted to it.

Dave

jonlowe

My Feedback: (12)

Dave,
Great idea! I will give it a try!

Jon

bla bla

Are those really easier to adjust?
It's hot, wet and as wobbly as can be in there... and it's that violent shaking, as opposed to normal vibration thats doing your servos in Bubba.
What is wrong with the area that balsa sheeted in the same pic'?
Cut a hole and drop in the servo(s)... ok so the push rod is twice as long but they're definately easier to adjust and eyeball an occasional inspection.
And don't mention that you cant get a straight run with the push rod as you've got to go over the fire wall and then drop down to the throttle/mixer arm.
You just turn the arms up instead of the normal down position.

Pro pattern

Hello everyone,

I’ve second that, it much easier in my opinion.
Well I also have this setup on my Focus II form the start.
I’ve seen how Bob did it and I’ve thought it is/was a need idea and decided to try it and till now no problem at all.
I’ve got about 360 flights on them and still no sign off any ware.
Still working as they were new.
But I’m using a Hyde A-type engine mount for my engine.

Here follows a couple of pic’s. (Now I’m using instead off the Z-bend, MK ball-bearing)



Regards,

Danny Koolman
www.arubarcclub.com

f3a05

Wow,360 flights with a Webra 160! That must be near automatic qualification for sainthood, surely!

Pro pattern

Hello there f3a05,

Well, after 360 I’ve needed to change the bearing.
Actually abet sooner, because I’ve didn’t notice (paid good attention) that my rear bearing was
wearing out, and have cost me some damage to my engine.
I don’t really know the actual sequence, but I’ve cracked my connecting-rod , cracked open
the down bushing in the connecting-rod, and sleeve of my engine due to this.

I think when the bearing went out, every thing went out of balance and have cost the previous
mention damage.

I think it could/would off lest about 300 flight with out any problem, but will need to change the
bearing’s (front and rear) when reach 300 flights or soon after. (to be on the save side )
Well now that it’s what I’m going to do. Every 300 flights I’ll change them.



Regards,

Danny Koolman
www.arubarcclub.com

Super D

Looks like a good idea, if and when I do it, I think I would use HS-65. I've had a lot better luck/reliability with 65's versus the 55's. They are also nearly the same weight and karbonite gears