Oxcart

I'm setting up a GWS A-10 and picked up a Quattro Lite with R610M receiver and
a pair of 241 servos (ignoring the steerable nose wheel - all the other flyers of this
bird say it's pointless extra weight :-) ). It would appear that a lot of the other
"Hog Drivers" are running the receiver off the same battery (typically LiPo) as the
ESC's and motors. Last time I was involved in this hobby (I'm not sure I want to
give away my relative geezerhood here ) most receivers didn't take too kindly
to dropping voltage. Then there's the issue of potential interference although with
an FM receiver as opposed to AM maybe that isn't such a big issue. Wanted to get
your thoughts on any "quirks" (if any - I'm not seeing much comment one way or
another about this rig here on RCUniverse) in the radio set plus any thoughts you
might have on running it in the GWS A-10. Possible issue - some folks think that
the GWS aileron setup is flimsy/flaky and are thinking about running a flexible
link from servo to aileron horn. Can the 241 servo handle that flexy linkage?
Any input you have here is appreciated. Oh, speaking of interference, the plane
comes with brush motors for the DF's......just about everyone is also switching to
brushless motors so take this into consideration when replying. Sure a nice forum
to have out here; and if nobody else has said so I imagine a lot of flyers appreciate
having you here. Thanks!

Duane
Lafayette, IN

dsnyder

Most all electric models of the slow/park flyer type use an ESC that has the BEC function so you run the receiver power from the flight pack battery, and this works well.

Are you thinking of running a direct pushrod from the servo to a control horn on the ailerons or something else, I'm not sure I'm understanding correctly? If that is it, will work ok, it may create quite a bit of differential which can cause poor roll performance if it is excessive. If you are thinking of bending/flexing a pushrod out, you may need to brace it with say a zip tie glued into the foam with a hole drilled in it for the pushrod to run through or similar.

Oxcart

Forgive me being a little behind the times, "BEC" would be an acronym for ?????
I gathered the function, I suspect, from looking at the radio paperwork - notes there
about interconnecting the radio and ESC with the battery if my guess is correct?

DuBro and maybe some others make or used to make a flexible pushrod that you could
bend much like the brake cables on a bicycle. My figuring was this - if I was going to
hack into the foam wing to insert spars, there would be little reason why I could not also
hack into the foam wing and insert one of these flexible pushrods. Looks llike there
should be enough space to keep the curve radius from getting too tight. Then mount a
control horn on the aileron and with the flexy cable coming in from the front at a nice
90 degree angle to the aileron I should be getting a good straight motion to move the
surface up and down. Pushing at the *center* of the aileron would, I would think, give
the most even pressure (for only one horn) across the entire width of the aileron, avoiding
the twisting motion that the GWS scheme appears to be prone to.

The GWS book appears to show some cockeyed aileron install that would apply the
movement to the *inside* end of the aileron and via some not-so-sturdy rods. It really
doesn't look all that well thought out, but maybe a holdover from another aircraft in
which it may have made sense. (also looks like really weak hinges that will also need
some re-engineering)

BTW, some initial checking out of the radio revealed an extra switch in the battery compartment
that isn't shown in the manual. From the back, it is above the row of servo reversing
switches. What is that switch for? Obviously, it could be something I should keep my
mitts off of but at the same time if it has an important function I'd just as soon know
about it. [&:]

What's really funny about all this to me is that 15 or so years ago I recall suggesting in
some internet newsgroup the idea of running Ducted Fans electrically. I got laughed
right out of the group. I also recall having a similar discussion I think with Bob Kress,
who I think told me that it would never "fly". I wonder if any of those guys remember
that? Seems like a lot of people are flying EDF pretty well these days, with a really
good amount of manufacturer support out there for lightweight gear and improved
motors and batteries.

Bob Kress sent me a couple RK049 fans, which I think was the smallest thing he had at
the time. Just to see what it would do, I crocked up a shaft and chucked it into my
Dremel MotoTool (mine is a ball bearing unit that will turn 20,000 RPM or so). Started
it off real slowly at first and slowly turned up the RPM's, and this little fan, even without
being in a proper shroud, was putting out some serious thrust. I was pleasantly surprised -
right up until the shaft, which unbeknownst to me had been slowly twisting, twisted
itself right OFF. That little orange fan took off across the room, bounced off a couple walls
and came to rest on the floor about 5 feet from where I took refuge under my workbench !
Lessons learned on THAT one.[:-] Funniest part was the fan was relatively undamaged.

Thanks again for the info, and keep those cards and letters coming in. [8D]

Duane

dsnyder

BEC stands for Battery Eliminater Circuit, it means that the speed control will provide the power to the receiver without powering the receiver seperately. I don't see why that type of arrangement wouldn't work on the ailerons, however I have set up and flown a GWS A-10 in the past and the stock aileron set up works fine. One thing to note, as with all electric slow and park flyer models, the key thing to avoid is adding un-necessary weight. Every bit of additional weight will only decrease performance. Beefing the model up here and there can have very large impact on the performance of the model, and can turn a good flying model into one that won't take off. Try to resist the urge to beef up slow and park flyer models as the flight loads on these types of models is very low.

On the switch, that switch doesn't serve any purpose, just leave it in the position it comes from the factory.

Oxcart

BEC, OK that makes sense and is about what I figured. Thanks for clearing that up.

OK, so to go back to the original question, will the receiver I mentioned be OK with
being tied into the same power source as the ESC's and motors? Between voltage
dropping and a directly fed potential interference source, I could see some problems
there. Sounds like a great location for a pi-net filter (a coil in series and a capacitor
either side of the coil to ground or common, as the case might be) on the + power lead.
Some motors and for that matter, some little microprocessors can put out some
wickedly nasty "hash".

I suspect that you are right about the STOCK GWS A-10. However, where I'm going
with this (along with a lot of the other guys posting on this bird at RCuniverse) is to
dump the stock motors and go brushless to get some teeth, power-wise. I pulled
and saved a very nice piece of video of a GWS A-10 that has been "worked up"
in this way, and I have to tell you - THAT was NO "slow flyer". THAT was an electric
fire breather, doing a lot of aerobatic stuff that I hear the stock plane with the stock
EDF's would probably pile into the ground on. Now that isn't neccessarily what I
personally am after, but I also did NOT buy an A-10 just to have a semi-scale whimp
that didn't have enough power to stand up to a few manuevers. It will be primarily,
for me, a considerable safety factor to have enough power available to get out of
a few potential trouble spots.....the fancy stuff can come later.

The video proves that it DOES work on this bird if done carefully and with
deliberation....which, of course, is why I am out in the forums asking questions.

You came highly recommended for JR and J-line radios and accessories, and your
expertise is obvious as I read many of your other replies before sending my
questions to you. My compliments on your knowledge !!!!!

So my question about the flexible pushrods I will also reiterate - do you know if
the 241 servo has enough oomph to handle that if the bends are not too "tight"
and the pushrod is sufficiently free in its movement?

Thanks again...

Duane

dsnyder

Yes, if you are using a speed control with BEC.

For those very reasons, for wanting the best performance, keep it light. Resist the urge to add weight, if you can improve something without adding weight, by all means do so. But avoid adding any un-necessary weight. I see that very often, where people add weight to "beef up" a model and make them unflyable.

Provided the pushrods move freely, I don't see any problem with that type of set up.

Oxcart

Sorry, not sure what you were answering "yes" to.

Roger on keeping it light - the other folks working on similar lines are
sharing information on specific materials; things like ultra light fiberglass
cloth reinforcements, specific adhesives that are foam safe but not "heavy",
carbon fiber composite materials, etc.

Glad to hear that you don't see any problems with the 241 servo and the
flexible pushrod given a good, freely moving installation. That is a big help.

Duane