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Thursday, December 28, 2017

52" Extra EXP__One Year Endurance Test



A year is a long time in the life of a 3DXA airplane. Even under the best of circumstances it's going to take a solid thrashing, and when it becomes your daily beater then the abuse really gets heaped upon it. My beloved 52" Extra EXP 53A began as an experiment, and has always been flown hard. It's been a little over a year since her first flight and this has been an exceptional plane, which is saying something for a plane that comes from such an exceptional line up.

At the time this project began, money was especially tight, and I did not think this out very well when I ordered the plane. When it came time to order the servos, I had about $50 disposable cash left, so I had to improvise. I took a set of highly abused Hitec HS85MG servos and sent them in to Hitec for service.
These servos had problems that ranged from stripped gears and broken cases, all the way to another that didn't run at all, and one that had it's servo plug ripped off the end! When I got them back they were in brand new-like condition and apparently ready to roll, for $45 including shipping. This certainly beat spending $120 for new ones, and I didn't have that money anyway.


You might notice the absence of decals on this plane. Usually I like to take it out a few times to cycle it in and out of the air conditioning, into the sub light and generally see how the covering is going to hold up. It usually loosens up a little, and it's far easier to tighten it back up if there are no decals on the plane. This time, though, I love the scheme so much I preferred to keep it simple and clean.


 
 


While this was not the ideal way to start a project, Hitec service has always done exceptional work for me, and in a lot of ways a rebuilt servo can be even better than a brand new one. When I was in the audio business I learned that electronic equipment usually fails in the first 30 days, or never at all. If you can get past the initial burn-in period, electronics tend to run and run and run. Since these servos had already been through the wringer, it's safe to assume they were past that burn-in point.

So, I fearlessly dropped them in. You can read about it in 52" Extra EXP__What To Do With Your Spare HS85MGs.  Here it is worth pointing out that Extreme Flight recommends Hitec's excellent HS5087MH high voltage servo and the HS85s don't even get a mention. Running these servos is something I took solely upon myself to try. Your results could vary, but all I have to offer you is what's worked for me.


Flying



It's no secret that I am an Extra man. I've always loved Extras, from my first SHP through the 48" EXP and 60" EXPs and right into the 52", which might be my favorite of them all. As with the Slick, there is something about the 52" format sets this series apart. In general, they are far superior to the 48" span planes, and fly nearly as well as a 60". The 52s are still a very convenient size, and since they fly so nearly as well as a 60", I predict 52 is where it's going to be at in '18. We've been told some more 52s are in the works, and I am shifting my focus to these planes.

I kind of lost track of how much time I put on this plane, but it was a lot. I was so pleased with it that it became my primary plane, so it was out there three or four times a week grinding out the flights. I flew it hard too, and have become really connected to it. In a lot of ways I equate this plane to my first 48" Extra EXP, which was also blue. Both were beautiful, graceful planes that opened new worlds for me. The 48" Extra redefined what I could do with a 3DXA plane, and the 52" is showing me how to do it all better.


Mostly the Extra does things the way a plane is supposed to do them. You may notice when I do breakdowns of any plane's attributes that I always compare them to the Extra. The Extra does not always do everything better than all other planes, but it still does everything well enough that all the other have to live up to it. The Extra is truly the benchmark all 3DXA planes must be measured against.


Extra EXP__Long Term Abuse Testing 002 from Doc Austin on Vimeo.
Long Term Equipment Evaluation
After a year's worth of abuse, I took the plane completely apart to see how things were holding up. It was all surprisingly good news.


First, let's talk about the power system, because there is the least to say about that. I plugged it in, forgot about it, and flew the crap out of it. That's it. That's all there is to it, and that's exactly what I have come to expect from Xpwr systems. I get explosive power and speed, and such reliability that once I bolt the cowling on that's the last time I think about the power system until I move it into another plane. While all of this might not make for riveting reading, it certainly makes grab and go flying a reality.

Not much to say about the airframe either except it still looks and performs like new. It helps I've become a little more careful with my planes and have stopped bouncing them off the ground as much, but this is a pretty sturdy beast anyway. Since I built the plane I have done very little maintenance, and it only took about a half hour with a sock covered Monokote iron to get the Ultrakote drum tight and flattened down on the wood. Generally I don't like Ultrakote, but I think working with it over the last ten years has taught me a pretty good technique for getting it nailed down. The biggest secret I have found is using a sock on the iron. It puts the heat where you want it and provides enough cushion that you are less likely to dent the wood, and it's soft enough that you don't scratch the covering or dull the shine. My planes look a lot better since I started using this method. This planes has looked great for a year and it did not need a lot of attention. I only worked on the covering because I was going through the entire plane, and I am pretty obsessive about keeping my planes nice. For the airframe, the worst of it is that it simply needed a good cleaning. While I had the servos out of it and the cowling off, I wiped all the covering down with lacquer thinner and that got it spotless.

Focusing on the servos, these HS85MGs have performed admirably, especially considering that they were in such rough shape before I had them serviced. I did not have one instance of stalling or blowback, and these servos are nearly as fast as the high voltage HS5087MH. Of crucial importance to me, these servos also center extremely well, so the plane trims out and stays trimmed out. You can't fly decent precision maneuvers if the trim keeps jumping around, and it takes the fun out of flying when you are constantly trimming the plane. On this plane, I trimmed it once and forgot about it.

After a year's worth of beat down, the servos are still working well. Since they were as good as dead before servicing, this speaks really well of Hitec service. Three of the servos were getting sloppy gears, but this is no surprise because they were starting to get a little of that when I sent them in for service. Remember, these servos were a collection that had been abused, thrashed and crashed. It's not even really fair to the servos to expect anything from them at all. They had already served me well past what you could reasonably expect, but service gave them a new life. That, and as you can se from the video, even after I wore the gears pretty ragged the plane is still really locked in. A full year on worn gears serving in my primary plane was a little too much to ask from them, so I replaced them with four more used HS85MGs that I also had serviced. The servos I just removed will go back in for new gears, and that will give me another set of essentially new servos.


All of the video was shot with the first set of servos, but I have since taken the plane out with a fresh set of rebuilds and she is better than ever, which says a lot considering she has been already  pretty jolly awesome. . She is trimmed and the CG is totally locked in and this is absolutely my #1 Plane,

So, we are set for at least another year of abuse, and probably even more if I can avoid the ground or banging the elevator when loading the plane into the car. This plane has been especially robust and reliable, and it's performed well enough to bring me a lot of joy.

This has been a jolly damm good project.



Thursday, December 14, 2017

52" Slick__More Fun With Hitec HS5085MG Servos

Doc's Disclaimer: Extreme Flight recommends Hitec HS-5087MH Digital HV Premium Metal Gear Micro servos for this plane. Using HS5085MGs in this plane is something I took solely upon myself to try.

The spectacular new 52" Slick and Extra EXPs are selling so well that occasionally retail outlets will run out of the recommended Hitec HS5087MH servos. When this happened during a build of my latest Extra, my friends at Hitec recommended I give the HS5085MG a try. That project remains a delightfully surprising success. I love that plane and fly it often. You can read about that in Even More Reasons To Fly The Extreme Flight 52" Extra EXP. That project went so well, it was only natural to want to try the 5085s in a Slick 580.

While the 5085 works really well for me in the Extra, the Slick 580 could be a completely different story. The Slick has a very tumbly, gyroscopic nature, and in a hard snap or tumble it can almost chew it's own tail off. The Slick is capable of some pretty incredible violence, and a much harsher test of a servo than the Extra. With this in mind, we were going to give to give it a try!

Worth noting is that the Hitec HS85MG, HS5085MG and GS5087MH are all built on the same servo case. Therefore, it's external dimensions and mounting holes are the same, and all three of them will happily drop right into the 52s pre-cut and pre-drilled servo openings. We used the HS85mg and 5085mg for the better part of a decade in the 51" Slicks, and with near perfect reliability too, so it is always confidence inspiring to work with products that have performed so superbly in the past.


 
 






Specs And Stuff
Mostly I have found Hitec servos suit just about everything I have flown in the last ten years, so I don't spend a lot of time pouring over specs and comparing servos trying to find that extra one ounce of torque or tenth of a second in speed. I'm not a spec guy and this isn't a tech blog. I just share what works for me.

 I just fly them hard and they either work or they don't. So far I have been happy with all my Hitec servos, but if I ever found one lacking the plan was always to upgrade to the next best Hitec servo, which so far has never been necessary.

  However, I know some of you want these details, so here we go.............


HS-5085MG Servo Specifications
Performance Specifications
Operating Voltage Range (Volts DC) 4.8V ~ 6.0V
Speed (Second @ 60°) 0.17 ~ 0.13
Maximum Torque Range oz. / in. 50 ~ 60
Maximum Torque Range kg. / cm. 3.6 ~ 4.3
Current Draw at Idle 3 mA
No Load Operating Current Draw 290 mA
Stall Current Draw 2150 mA
Dead Band Width 2 µs
Physical Specifications
Dimensions (Inches) 1.14 x 0.51 x 1.18
Dimensions (Metric) 29.0 x 13.0 x 30.0
Weight (Ounces) 0.77
Weight (Gram) 21.9
Circuit Type G1 Programable Digital
Motor Type 3 Pole Metal Brush Ferrite
Gear Material Metal
Bearing Type Top Ball Bearing
Output Shaft (type / Ømm) Standard 24
Case Material Plastic
Dust / Water Resistance N / A
Connector Gauge (AWG) / Strand Count 28 / 20 



Advantage Of Simplicity
The 5085 is a 6 volt servo, and this plays out in a simple installation that does not require a separate BEC and it's associated rat's nest of extra wiring, solder joints and complexity. You simply plug the Airboss 80 straight into the throttle channel of your receiver, let the Airboss' onboard 6 volt BEC do it's thing, forget about it and fly. Like this this Airboss' on/off safety switch still works, an important part of my preflight procedure for making sure I don't have a nasty propeller accident.


Here you can see how well the Airboss snuggles into it's designated location. With the absence of an separate BEC, the installation is much cleaner with less wires and less clutter. The standard Airboss installation and operation is what I have become used to over the last 10 years and, as such, this is the way I like doing things.

More Simplicity
Something else worth pointing out is how Extreme Flight has cleaned up the radio installation. Using hooks cut into the formers, you can restrain the servo wires so they don't flop around, and they stay out of the way when you are working in the radio compartment. This also looks very professional, so it's a win/win.


Xessories
Once again I relied exclusively on Extreme Flight's brand of aftermarket accessories. I love the servo extension and servo mounting screws. For this project  I was a little short on funding and was not able to buy the terrific Xessories servo arms, but I can always add those later. You can read more in Once again I relied exclusively on Extreme Flight's brand of aftermarket accessories. I love the servo extension and servo mounting screws. For this project I was a little short on funding and was not able to buy the terrific Xessories servo arms, but I can always add those later. You can read more in Xessories Update.   


Set Up
Nothing new or exciting here because all that is important is that it simply works.
I have notched that the ball links that have come with my last few kits work much more smoothly with less drag. I usually tinker with the ball links a little to loosen them up, but on this kit all I did was bolt them on and they did not need any further attention. I was so easy I felt a little guilty, so to ease my conscience I put a drop of silicone oil on each one. I used to put a lot of effort into this part of the build, because it was as important to get it right as it was annoying. It's nice that now it's a bolt on, no tinkering operation.


Elevator Set Up
Nothing special here except Extreme Flight's excellent and exclusive G10 servo arm extension. I do something a little different from most people here, and instead of using the arm that comes with the servo, I use the anodized blue metal arm that comes with the HS7245MH (and other  Hitec) servo. This is a metal arm that will not get sloppy, wiggle around on the servo output shaft, and give you a sloppy connection. The arm stays tight, so I believe this is probably the best arm for this application.
Aileron Set Up
Once again I turn to the reliable Hitec PN55709 arm set, and I use the shortest arm, with the ball link on the outer hole. The Slick seems to have a slightly faster roll rate than the Extra, so for this plane I am most comfortable with the end points set at 125%.





 Rudder Set Up
At the risk of being repetitive, once again it's the Hitec PN55709 short arm.  I have the end points on my transmitter cranked to the left, and I only have to back it off 10% or so to the right.  This gives me full deflection in both directions.


While all of this seems too simple and too easy, that's actually a good thing. Simple means it is much less likely to ever fail, and easy means you are more likely to get it put together right. Simple and easy are two extremely solid concepts that pay big dividends on any build.
Flying
I was pretty confident these servos would be really good in this plane, and that's exactly how it worked out. The 5085 is about 10 years old (maybe even older). It is fully developed and refined, so they have plenty of speed, power and precise centering.


Just like the 5085mgs in my Extra, the Slick trimmed out all by itself. I did not touch the trim levers all day. It was perfect. The Slick also stayed trimmed. This tells me that centering is exceptional, but we knew this from the 5085 Extra test.


Speed is really good and I can't tell much difference between this and the 5087mh. No stalling, no blowback and I expect the same kind of reliability I have always had with Hitec producys.
Generally I am tickled silly with this plane for a lot of reasons. It was an effortless build, the build was also flawless (a first for me) and it flies perfectly. This might be the nicest plane I have ever owned. As far as overall project satisfaction goes, this one gets a 100%. 


We usually try to shoot two or three videos, but today was so much fun we forgot that's why we were there! I flew the Slick all day and by the time we got around to shooting we were all tired and hungry. We'll try to get more tomorrow and maybe do a separate flight report.




Slick EXP__Testing 5085MG from Doc Austin on Vimeo.