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Tuesday, January 22, 2019

Extra EXP__Flying The Elusive Magic Wunder Servo

 The 52" Extra and Slick were radical enough when we first got them, but the latest advances in Electronic Stability Systems and premium servos have pushed them to a level that many of us didn't see coming. First, I flew them for about a year using the recommended equipment with great success. Like this they were beautifully flying planes, and then we went to the next level experimenting with a good ESS. I have been flying the planes equipped with Aura 8 ESS for about a year, and am extremely pleased with the results.

Just when I was starting to think it could never get any better, glowing testimonials about ProModeler servos were hitting the net. A few of my RC Groups friends had tried them and were rabidly praising them, so I thought this had to be worth a shot, especially since my standard servos were two years old and getting a little tired.

I started with the ProModeler DS100 servos, as seen in Awesome Servo Testing__ProModeler DS100DLHV and Slick 580 EXP__The Ultimate Set Up. More than ever I was convinced this was the absolute end of development for 52" class equipment. Then John Beech told me about the DS150. While 100 inches of torque from the DS100 is enough to rip stubborn stumps out of the ground, the DS150 features half again as much at 150 full gut wrenching ounces.

When you already have enough torque (which the DS100 has), you might not think more would be useful, but it is. More power and more torque just means the servo is not as stressed as less powerful units. It's a big, powerful monster that is just loafing around taking it easy, and that's really good for reliability. Overstressed stuff doesn't do so well here.

While this is really sweet to have, the DS150 also features more speed. They are not so super rocket fast that the control surfaces blurr when you move them, but they are visually faster than the DS100, and I was happy enough with those. If you have any doubts, you can always check the specs on the page linked to below.

Unchanged are all of the DS100s quality construction, million cycle rated potentiometers, and ultra solid gear train construction and alignment, among way too many other things to mention here. For a closer look and more technical info, please check John Beech's excellent write up on the ProModeler site (scroll down a bit). Even if you are not interested in higher quality/performance servos, there is so much good information here it's well worth the read about servos in general.

If there is any downside at all, it's the extra $15 tagged onto the price tag. For extreme hardcore 3DXA pilots who hammer their equipment mercilessly, that's only $60 total on a $650 plane. When you push to that level, you need everything you can get, so that kind of money is just what you have to spend. You want the best, so you spend the money, install them and forget about it, which is exactly what you want from a servo. I don't need them to sing, and I don't need them to dance. I just demand that they perform, and even the DS100 far exceeds that. The DS150 is just more of all that.

This price is still extremely competitive (and sometimes less) than other company's premier servo, so most of them will spend it happily. For regular 3D sport pilots, the DS100 at $39.99 is still going to be way more servo than they can get for a comparable price.

Astute readers will remember I'm not necessarily a tech guy (and don't pretend to be), and this isn't a tech blog. I'm a flying guy and this is a flying blog. Specs are great if you love numbers and want to nitpick speeds down to the hundredth of a second, or torque down to the last quarter ounce, but I believe the real story is always in the flying. Specs will give you an idea of how well the servo will work, but I don't believe anything until I fly it.

Now, if you are a spec guy, you can check the specs and make up your own minds, but I'm going to stick to telling you what things do in the air.

FLYING

 

Extreme Flight Extra__No Title.mp4 from Doc Austin on Vimeo.


The most important improvement I've noticed moving to ProModeler servos is how their superior centering changed the flying dynamics, and even my own style as I adapted to that. Being able to trust the plane to go where you point it and stay where you put it every time, all the time, is such an invaluable thing you can't appreciate it until you have actually flown the plane. With both the DS100 and DS150, you trim it once and forget about it. The plane stays in trim for flight after flight, and you can trust it to stay trimmed.

This is extremely important when trying to fly precisely, and especially on the deck. You have to know when you center the sticks the plane isn't going to climb or (worse) dive, yaw or roll on you, and the lower you fly the more important this is. In this respect, it's all about trust, and when you can trust the plane, you can fly it better and more confidently.

In this respect, these servos are virtually inseparable, simply because the DS100 already centers at a level that will transform any plane you put it in. There may be some credibility in the theory that higher torque will give you tighter centering, but once you get to perfect it's overkill.

John Beech explained to me that the DS150 would work better for flying 3DXA with a gyro because the faster servo reacts to the gyro much more quickly. After flying the servos I have a better understanding of what he meant. How this plays out is the plane is so much better locked in and you will feel much more "connected." It's much the same reaction I had after flying DS100s for the first time, though not quite as shocking. I was not prepared to believe anything could be better than the DS100, and while the differences are subtle, they are there.

I've been flying this red Extra so much,. and I am now so used to the feel of the DS100 that I fell into the groove right away. I had to work up to find the limit because I was trying something new, but after a flight or two I could tell the DS150 equipped plane was just better all the way around. I have flown my DS100 equipped blue Extra back-to-back with my DS150 equipped red to give me an instant contrast between the two. The difference was not blinding, but it was there and the DS150 is definitely better.

So, what does all of this mean to you? I think the average sport 3D pilots will be delighted with the DS100 and never need anything more. Most of them will never even dream there is anything better, like of like I was after flying the DS100 the first time.

The DS150 is more for the demanding pilots who fly on the ragged edge all the time. I've been flying RC for over 40 years and it was hard for me to pinpoint the differences. It's a subtle improvement, and this is what you get when you move up in quality. You pay more for smaller improvements, but if you want everything you can get, it's worth it.

. The DS150 is for the guy who is scratching and clawing to get every last possible bit of performance he can, and for those guys there's really no reason to look at anything other than the DS150.

SET UP

I used a mixed bag of servo arms on this plane to get the desired set up. First is Xessories excellent 1.25" 25 tooth spline arm. I've used these on all of my 48, 52 and 60" plane's elevators since their introduction. I would use this arm on everything if it were available in the 7/8" I prefer for my ailerons. The other is the less blingy, but completely functional ProModeler PDRS101 1" arm t5hat features the second from the outside hole at 7/8", so that's perfect for me.

Ailerons
Using ProModeler's excellent 1" arm, I get a perfect 33 degrees of aileron. Some guys like more, but I can fly this much more smoothly than a longer arm.


Elevator
Here I like the 1.25" Xessories arm. I'm getting about 84 degrees of travel with this. If you are comfortable with less, use the next hole in. I had to use a flat file and open the servo hole downwards a litte to get the ball link to clear the bottom of the stab, but that was minor and only took a couple of minutes.

Worth noting is when I tried the DS100 in my blue Extra, all I had was a 1" arm, but that was still enough elevator I could fly my whole program. The extra throw is used more as an airbrake anyway, so if that doesn't suit your style, the next5 hole in is still plenty of travel.

Rudder

Here I used the second hole in the 1" arm, which was not quite enough. I used the travel adjustments in the Aura to turn it up about 10% on each side and the rudder almost hits the elevator at full deflection, which is just perfect.
Notice the I put the ball link on the inside of the servo arm. This gives it a straighter shot to the control horn at full deflection, which make it more efficient.

Monday, January 21, 2019

Slick 580 EXP__The Ultimate Set Up




The 52" Extreme Flight 52" series planes are such serious pieces that they deserve the best equipment you can throw at them. As modelers we are always tinkering with this or that, even well after the plane is fully dialed in, just looking for that extra something to give us a performance edge. The journey with the 52" EXP series has seen me doing a lot of experimenting, especially with servos and an Electronic Stability System (ESS). Everyone has their favorite stuff, but I think I've found the perfect combination.

First, the recommended equipment works just fine. It's really good stuff. It's just not perfect, and perfect is what we are after, right?

With the Extreme Flight Xpwr power system, an Aura 8 ESS, and now ProModeler's premium, hyper quality DS100 servos, I think there is no further room to improve the package other than to fly the crap out of it and enjoy it like The Boss and Ben envisioned when they designed it. As of right now, this is the finest flying plane I have ever owned, followed closely by my similarly equipped 52" Extra EXP.

Let's start with the flying, because that's what matters most.
FLYING

We have seen and documented how a good stability system works with the Slick in Slick 580 EXP__Flying With An Electronic Stability System.


The final tweek to get the most our of the Slick was moving to hyper quality ProModeler DS100 servos. Most servo discussions revolve around torque and speed, which while important don't give you everything you need. We had enough torque and speed before because the planes flew beautifully without any crippling stalling or blowback. More of torque and speed are good, but any more than that are just numbers on a piece of paper. It would be a mistake to buy any servo on those two attributers alone.

However, it's worth noting the DS100 has nearly double the torque of what we have been using, and they are also faster. These are good things to have, but to me the most important attribute of the DS100 is it's dead solid centering. This shows up in a monumental way in the flying, which is what counts.

Generally smaller servos don't center as well as larger ones, but ProModeler has addressed this with solid engineering and quality manufacturing. We don't do a lot of tech pieces because I am first and foremost a flying guy, but tech happy types would find John Beech's article on this servo most informative, and better written than I can manage. There are also excellent pictures of the servo's insides where you can clearly see the attention to detail. Scroll down a bit........... http://www.promodeler.com/DS100DLHV

We all know how difficult it is to fly an out of trim plane, and you get much the same effect with a servo that doesn't center well. You will come out of a perfectly executed maneuver and the plane will either dive, climb, drop a wing, just something that wrecks the look of the move. A poorly performing servo will also have the trim drift off, and then you have to trim it all over again. That, and you are always fighting the damm thing, which is tiring and less than fun.

What we have been using have not been bad. They were actually quite good, but not perfect. In the millimeter perfect world of low level 3DXA flying, nothing but perfect will do, and the DS100 excels here. I have nor done any scientific experiments to measure the preciseness of these servos' centering, but I don't need to because I could tell the difference as soon as I was finished trimming the plane. I trimmed it, turned it around to check it, and it was perfect, time after time after time, and well into 25 flights I have still not touched the trims again. Set it and forget it.

What you want is a plane that trims and stays trimmed, and when you put it somewhere, that's where it's going to go. You certainly don't want the nose dropping at the end of a low level maneuver, or ballooning up when you complete a move. When you let off the stick that's where you want it, and that's where you want it to stay.

This makes it easier to set up maneuvers because you are not having to make corrections. You line it  up, let go and let the plane do the work for you until you are ready to do something else. This takes so much work load off the pilot that the fun factor sails off the scale.

This is priceless for precision maneuvers because you point, shoot and fly away in a straight line, almost like that's how it's supposed to fly. Precision looks smoother, more controlled, and almost computer like, which is what the judges want to see. If the plane isn't tracking, that's a downgrade, and then a second downgrade for the correction. You take two hits for no reason other than the servo let you down, but now that's no worry. I've never flown a small plane that tracks this accurately.


You might think in 3D that this is less important because you are always moving all the sticks and are not at neutral that much. However that's not true because you do go to neutral, and if the servo isn't centering perfectly that's going to throw you off track. Perhaps the biggest surprise was just how much this did help my 3D.

Over all, you trust the plane more and can push it harder because it does the same thing every time, goes where you point it and stays where you put it. You used to have to get into bigger planes to get this kind of precision feel, but these servos now bring the best out of already perfect airplanes to the point I will stack any of my 52s up against almost anything for flying smoothly and precisely.


So, from all my experimenting and flying, I can truly say this is the perfect set up for these planes.








Power System
The obvious choice for a power system is the Xpwr 3910 and Airboss 80 ESC that I have been using with great success for over two years in all my 52" planes. The 3910 was designed with the 52" series especially in mind, and that shows up in the performance. I've already written considerably about this combo, and you can find it here: The 52" Class Is The Future of Mid Sized 3DXA Performance. I'm not looking around for a better power system simply because we don't need one, and it probably doesn't exist anyway.


Electronic Stability System
Selecting the power system was the easy part and was never under consideration anyway, but it gets a little more complex with an ESS. There are a lot of really good ones so pick the one that suits your needs and budget best. You can score an Eagle Hobby unit for slightly under $20 and it's crazy simple to set up, or you can break the bank on other units.

One consideration is ease of programming, and the complication of some units scares people off. I put off trying an ESS for far too long because it was something new I didn't want to have to learn, which will happen to a lot of you once you get older and more stubborn. Once I flew a few planes with the Aura though, I liked the feel so much I resigned myself to just having to learn, and it was not nearly as bad as I thought. Once I dug into it I had it mostly figured out in about an hour, without even reading the instructions. It's not that complex. It just looks that way from the outside. I also have a friend who is a Flex rep (imagine how interesting some of our conversations can be!) and he helped me with one or two things I was not sure of, and that certainly eased the path. In the end, it was a learning process, and the performance gain was so well worth it I am wondering why I resisted to begin with, and I think that's going to happen with almost everyone eventually.


There are plenty of other good ESS systems, but I now have extensive experience setting Auras up for 48-60" planes, and I have a solid baseline set up. When I initially set this Slick up with an Aura, I used my baseline and everything was perfect the first time I flew it. So, once you learn, there's nothing to it and nothing to be afraid of.

Much like with race cars, technology is a tool you can use to find untapped hidden performance. Since I have a racing background, I actually enjoyed this challenge, and now an ESS is less of an intimidating monster and more of a means to make the plane fly better, which after all, is what we are all chasing, right?

 You can choose any system you like, but the Aura is generally regarded as the best. It's a tad pricey, but at $100 it's not completely crazy. I could have gone with a lesser expensive unit, but guys are flying these in $20,000 jets, and you would have to be crazy to trust that much money to a lesser expensive and maybe not as reliable unit. I'm not setting up a sales pitch on the Aura. It's just the one I chose based off what little I knew when I started flying ESS units. Since they work so well, there was no reason to change.

I've written considerably about setting up Auras in 48-60" planes in blog articles you can find here from early 2018.

Servos
There's always considerable discussion regarding servos, and while the recommended servo works extremely well, I'm always open to trying something better, provided it's enough of a performance, reliability, and durability improvement to make it worth it. Any time I look at new equipment, it's got to have those three things, and you can't compromise on any of them. I found these in ProModeler's DS100 servo, and was so startled in flight improvement that I am currently converting my entire fleet.


I've previously written in detail about converting and flying my Extra with a set of DS100, which you can read about in Awesome Servo Testing__ProModeler DS100DLHV. That project went so well that I could not wait to try a set in my Slick.

The Conversion
A lot of guys are switching to the DS100 in their 52" EXPs, which is an easy operation I will briefly outline here. First you have to change to 25 tooth servo arms. You can either use the superb Xcessories 1.25" arm, or ProModeler's less blingy put totally functional PDRS101 and PDRS102 (double) arms. I went with both for functional reasons. The Xessories arm gives you a whopping amount of throw on the elevator and the ProModeler arms have the 7/8" hole I like for my ailerons and rudder. That's the simple part.

A little more involved are the servo holes, but it's not a big deal. Other servos in this size use two mounting holes, but the ProModeler is much more solidly mounted on four. With the servo so locked down like this, it can't wiggle, and it's also not going to wiggle the plane out of trim. This might seem to be an insignificant detail, but with only two screws you can move the servo around by hand, so what's it doing under load? If you want precision, you need a dead solid mounting and this is it.

If you are converting a plane you will need to plug the existing holes, but it's only two per servo and there's a really neat way to do it.  Plain old every day ordinary toothpicks work perfectly. I jam these in there and CA them. Once they set up. I snip them off as flush as I can, then grind what's left down with  small dremel drum. It doesn't look so bad and the servo covers it up anyway, but now you have a solid base to mount the servo on.



I suppose if you were careful enough you could drill the new holes and miss the old ones completely, but then if you missed you'de have to go back and clean up this mess. Plugging the holes takes ten minutes tops, and it's time well spent to avoid having a potential aggravation.

Servo Arm Set Up
Since I had such stellar results with my Extra, I almost copied that set up exactly. At the time I did not have any 25 tooth 1.25 arms, and used the ProModeler 1' arm, but for the Slick I bought Xessories 1.25" arm.

Ailerons
Here I use the 1" ProModeler arm, with the ball link on the second from outside hole. This hole is 7/8s from center, which is what I like on these planes.


Elevator
I love the Xessories 1.25 arm. It slides on easy and with the cinch bolt locking the arm onto the servo output spline, it will never come off until you take it off. This becomes even less of an issue with ProModeler's use of a 3mm allen bolt. You can really crank that baby down and not worry about stripping the head like you can with a Phillips bolt. Especially for the elevator, I like that kind of security.




Rudder
Again, the ProModeler 1" arm and the 7/8" hole gives me the perfect amount of throw. I think I had to add 10% or so more throw in the Aura, but it was really close.