AJ Models 93in Laser 230Z

As often happens, one of these caseSTUDY articles revolves around a customer conversation. This one is no exception.

And note, when clicked, links open within their own tab (so you don’t lose your place with this article).

Intro

So the other day a fellow reaches out asking questions about servos. Turns out he’s been flying one of Andrew Jesky’s Laser 230Z models for quite a while – the one with a 93″ wingspan. And the guy’s rather peculiar in one regard . . . as I’m about to find out.

First, amongst experienced pilots, the Laser 230Z is a very well regarded model. Principally, because in the right hands, and with the right setup and servos, it’s a Swiss army knife amongst aerobatic models.

Setup

Focusing on a concept, I’m saying in the right hands, with proper servos and setup, it’s a supremely capable IMAC model – ideal for precision maneuvers. But in the hands of a hooligan, and equipped with brutally fast servos and set up for extreme throws, then it’s capable of flying the hardest level of XA-maneuvers. And yet, when set up with the right servo arms, regardless of servos, it’s so tame and well behaved a novice pilot, one comfortable with his second model, can readily land it as slow and gentle as a trainer!

All this from one aircraft is pretty amazing (and a testament to the Jesky design’s fundamental soundness). But note how I used set up three times! Point being, while servos are important, when optimizing this model to be different things for different people, the setup is key.

Background

Making this story interesting was him saying he’d reached out because he’d already had a couple different servos in the model. Hasn’t been satisfied with any. Wondering what we’d recommend.

Honestly? This put me on high alert. Why? Simple, it’s because the very last thing in the world we want is for ProModeler to be yet another servo with which he’s dissatisfied!

So we delve into how he flies (IMAC stuff), his equipment, and what’s specifically wrong about the other servos that’s leading him to be unhappy (they’re well respected products, in my estimation). In essence, I’m trying to get to the bottom of what’s going on.

Turns out he’s absolutely anal about centering. Whew! This kind of ‘peculiar’ I can deal with because I’m peculiar about centering, also. It’s why we pay for the pricey Nobel 1mc potentiometer instead of a cheaper solution. And my relief’s because this is totally copacetic.

Saying centering concerns come with the territory when dealing with IMAC, SPA, and F3A-type pilots. We address this all the time.

Anyway, after a fairly long conversation (45 min), we hang up and I move on to what’s next. After all, few are actually ready to pony up for pricey servos upon first contact.

On becoming a customer

Then out of the blue a few months later, photos from my now customer, arrive in the inbox. Turns out (unbeknownst to me), he’d ordered servos and a 50mm pulley and been flying them. What’s more, he’d kindly attached a photo of himself alongside his model.

Best part? He’s not just happy, but singing our praises! He’s telling his pals and honestly? His is the kind of note that makes you glad you got up in the morning.

I immediately sought and received permission to share the photo, and his thoughts, and penned a note regarding the experience. I offer it in hopes you find within a useful kernel of information.

At our core there lies a belief in challenging how it’s always been done. We approach things differently, challenging the traditional ways by giving engineering a free hand over marketing. This manifests as problem-solving within product development resulting in consistently thoughtful touches. That we do it with servos, explains your interest and we welcome your joining us in challenging the status quo.

On selecting servos

So the 93″-class of models are actually bound more by powerplants than wingspan. These encompass 85″ wingspan aircraft at the lower end of the range, and 94″ wingspan models on the upper end.

Typically, they’re powered by twins like a DA70 (my own PAU 89″ Extra 260 has one). Also, thumpers like DA60 (or even the powerful DA85), as well as 12S electric propulsion systems.

And they’re a great size model to own because they fly big, without actually ‘being’ too big, if you catch my drift. And they have money saving advantages, because this class of aircraft use single versus dual-servo ailerons.

Servo-wise the right answer is largely determined by three things. These being pilot, budget, and goals – no surprise there.

And by pilot, I mean a specific type.

Pilots

In our experience, there are three basic types of pilots. Of course there’s an infinite number, but if we slice and dice to put them in three buckets, they’re the club pilot, hotshot, and hooligan.

And look, guiding you would be much easier if we were mates. Like if I knew how you fly because we flew together then I could maybe say, bluntly, ‘You’re never going to perform a crankshaft, forking over $140 for DS635 servos is stupid because the only place you’ll feel the difference is in your wallet!’

Or maybe, ‘I’ve seen you fly inverted on purpose once, and I could hear your knees knocking, those $50 servos are plenty good enough for what you do.’

But since we’re not mates, meaning I don’t actually know how you fly, then we have to trust you to be true to yourself in making the decision. Best I can do is try and help you see yourself more clearly.

Club pilot

The club pilot is what’s often referred to as a gentleman flier. Pilots fitting the description of ‘club pilot’ encompass a wide range of skills.

For example, on one end of the scale of pilots are ones who fly a lot. They go to the field two maybe three times a week and burn lots of fuel. They know everybody, everybody knows them, and they’re totally solid pilots who appreciate good centering and saving money.

Then there are those who don’t fly as often. They fly fairly high and rarely fly inverted. They’re perfectly happy flying circuits and making the occasional low pass and on their way home at the end of the day, quietly utter a sigh of relief and reflect on the successful landings. This fellow flies once or thrice on any given weekend, and enjoys visiting most of all because for him flying is about the fellowship and a break from the M-F grind. It’s about the fun.

Then there’s an in-between type of club-pilot. Talking about pilots with solid technical skills. Talking about the über competent sticks who attend a lot of events, fly a lot, and for whom centering is supremely important.

Hotshot and IMAC pilots

Then there are folks who can competently perform 3-rolls down low are considered hotshots (low being 10 feet). They like to show off. And they’re such good stick they’re often called upon to do the majority of test flights for other club members.

These are the guys at the very top end of the pilot skill set. They’re totally into performing maneuvers smoothly. Think IMAC types who pretty much comprise the best pilots in the club.

Also included are pilots whose repertoire of maneuvers includes credibly performing many from the old FAI schedule.

IMAC and hooligan pilots

There are two pilots in this group, there’s the disciplined guy who practices several times a week and goes on the contest trail. Talking about the guy seriously into IMAC competition.

Then there’s the guy who is an utter natural sticks. Now we’re talking about guys blessed by God himself with a talent that brings the show to a stop when they take to the sky. Didn’t get there without practice, but they make it look easy.

You know what I mean, the ones for whom folks stop flying just to watch as they performs crankshafts, rifle rolls, and wall maneuvers. Plus Harrier rolls within ten feet of the ground the length of the field!

So bearing in mind who ‘you’ are pilot-wise, we’ll make equipment recommendations for your 93 inch AJ Models Laser 230Z. Just remember what Shakespeare said . . . to thine own self be true.

But first, let’s touch on budget.

Budget

After pilot type, budget is second on the list of considerations. Money lurks in every decision. Be one thing if we were all rich but the facts are money doesn’t grow on trees, so selecting servos involves a keen focus on what’s important.

I’m going to concentrate on three servos, one ranging in price from $50, through $100, to $140 (although I’ll mention others worthy of contemplation).

However, beyond servos, I’m also going to present servo arms for which you should budget because they’re not all the same. And the proper ones are crucial in achieving the proper setup. Yes, setup!

And we’ll lightly touch on stuff like getting enough juice to the servos. If you don’t, they just won’t function as designed. This last being true whether you use our servos, or opt for a competitor’s because we’re not dealing with opinion, but with physics, instead.

These things aren’t expensive, but they’re money out of the budget.

Goals

After pilot type and budget, third on the list of considerations are your goals. Every pilot is on an arc of development.

Like there’s the guy getting started with 3D who will put himself out there for two hours every evening on a simulator. Why? Because he’s seen YouTube videos of Jase and wants to reach for the brass ring.

Then there are guys who have enough stress Monday through Friday and fly a model like this Laser for the fun of it. They love the look but they have absolutely zero intention of ‘ever’ doing a Harrier roll.

This circles back to budget and what I meant about being true to yourself because you may ‘choose’ to equip your model with our fastest servos, and long ass servo arms to impress the peanut gallery with 45° throws in the blink of an eye – but – if you never actually doing those kinds of maneuvers, then you’ll just be pissing away your money. Saying, choose wisely.

Note; I recognize for many of you it’s not so much because you can’t fly like a hooligan if you really set your mind to it (because you’re a decent stick and can learn, especially using a simulator). Suspecting it’s more like you’re not really into stressing over things and want the aircraft to perform realistic flight – more like maneuvers the aircraft would do at an airshow – instead.

Anyway, most serious of all are the IMAC competitors. The goal for these guys is to focus on a single maneuver and work, and work, and work until they perfect it. And then go to an event and prove to their mates they can score well flying it.

All of these guys, each with their own goals, need servos that can take what’s dished out – and – get in return, equipment you can depend on.

Next we’re going to sort the servos in terms of three broad categories of good, better, and best, and along with servo arms and extensions make equipment recommendations for your AJ Models Laser 230Z.

Equipment recommendations

For pilots who want the good stuff, but don’t want to spend stupid amounts of money, allow us to introduce you to the ProModeler DS90DLHV and DS360DLHV – both DL-series standard class servos.

Good

• Qty 5) DS360DLHV – 2 each for aileron and elevator, plus rudder
• Qty 1) DS90DLHV – throttle and possibly a 2nd servo for choke
• Qty 4) PDRS35-25T arms (or PDRS25-25T if you detest touchy)
• Qty 1) PDRS50PP-25T pulley (pull-pull rudder, otherwise, a 5th 35)
• Qty 1) PDRS105 – arm (throttle and choke)

Gear train

At $30 for the DS90DLHV, and $50 a pop for DS360DLHV servos, what you get are servos with the most durable and vibration resistant of all gear trains, stainless steel. And not just any stainless, 330 for the bull gears and hardened 412 pinions.

Spot Welding

But there’s more because if you’ve been flying servos equipped with brass steel gear trains, let me show you what you’re gonna get with these rugged servos, instead.

Part of making us different, the whole reason we give engineering a free hand, and behind ‘why’ for contracting officers and industrial users selecting ProModeler are thoughtful touches. Like spot welding the 6/7 compound bull and pinion gears together to reinforce them.

Or as has been observed, God is in the details

Bronze Bushings

DL-series servos also feature a rugged impact resistant upper case. One that’s injection molded of Nylon 6.6 fiber-reinforced polymer. This is the same kind of stuff used in a Glock handgun frame – and for pretty much the very same reason . . . lightweight and tough!

Moreover, to give you a long service life, one easily rivaling a pricey all-alloy case (whilst keeping weight low), and unlike others their class, you get bronze bushing reinforcing the gear shaft pockets.

13 Seals and O-rings

Another thing you get with DL-series servos, important because they’re mounted external to the aircraft, are 13 seals and o-rings. This matters not just because of the oil in the exhaust due to the premix, but because so many of you love to fly with smoke oil.

Saying this is also a big deal.

Million-cycle Pot

Also worth noting is this; you get the same 1-million cycle Noble 1mc potentiometer in a $30 servo as in our $100 and $140 servos. Means exactly the same great centering performance.

By the way, we’re occasionally asked why we don’t use a Hall Effect potentiometer like some newer brand imports. We don’t for good reason and to keep from going into a dissertation, maybe just review this brief article and learn more:

• About pots vs Hall Effect sensors

Heat Sink Center

So it gets better as you consider using DL-series servos because you also get a center case CNC-machined from a solid billet of 6061-T6 aircraft aluminum. What for? Simple, to give you better cooling.

As for when this is super important, it’s when your servos are working hard because heat is the enemy of electronics. Moreover, I suspect if you look at servos you already own, ones also equipped with alloy centers, what’s often missing are cooling fins.

This is a case where less is more because it’s within what we removed, excess aluminum by machining the fins, that you benefit. Point being, ProModeler servos use the center case as a heat sink!

Potting Compound

Something else you get with DL-series servos are how we coat the PCB with potting compound. This protects them from vibration and shock. It’s an aerospace technique, which flows and surrounds the surface mount components in sticky compound (which stinks to high heavens, and which we call monkey snot).

What costs about doing it is the time to apply – and – because we have to wait for it to cure. So time really is money during assembly. As for what’s in it for you, and why hobby grade servos don’t do it, just follow the Benjamins because unlike our direct business-model, their business sees a lot of folks wetting their beaks in getting servos into stores (e.g. the importer’s 15% cut, distributor’s and their 25% cut, and the hobby dealer’s 40% cut – all for just touching the servo and – for which you pay).

So back to the monkey snot; the end result of using it your servos are more shock and vibration resistant because of it. And what’s the alternative, doing without? This is what the hobby grade servos do.

Why? They’re rely just on the strength of the solder to securely hold delicate surface mount components like microprocessor, diodes, resisters, and FETs to the circuit board. This is a problem awaiting a ass to bite.

Saying there’s a reason the airlines, NASA, and the Air Force insist on potting compound within the avionics. And this is probably why you’d prefer your servos have it, also. Basically, solder easily fractures due to vibration.

Anyway, if you agree vibration is bad juju for your servos, then this matters! And it’s what engineering-driven means, and why modelers are switching to ProModeler.

MIL-STDS

Know what else you get with DL-series servos? Eight MIL-STDS.

Our principal customer insist on them and you benefit, too because we’re not building two grades . . . so you don’t pay a thin dime more!

What do you give up?

It’s reasonable to wonder, ‘What do I give up buying $50 servos?’

Maybe a lot, maybe nothing. Maybe nothing important to you. And probably less than you might imagine. It depends.

For example, while they’re fast enough for mild-3D at 0.14sec/60°, like quick enough for hovering and torque rolls, they’re neither fast nor powerful enough for rifle rolls and crankshafts.

Moreover, while they’re great for some IMAC maneuvers due to their good centering, and while the brass bushing reinforced polymer case helps them last a long time, an all-alloy case will last longer if you fly single cylinder engines.

Saying unlike a smooth twin, or electric powered model, a big thumper like a DAS85 will beat the ever living shit out of all the equipment, to include the servos. What happens is the plastic (where the steel output shaft bearing seats) begins to wear over time (years, though) and needs replacement. True for any servo with a polymer upper, not just ours.

Output Shaft Reinforcement

Now toward that aim, we have reinforced the DL-series around the output shaft with. Eyeball the before and after to see how this iteration is stronger.

Better – intro

Nevertheless, there’s a reason why high time pilots, folks who fly IMAC (meaning they practice several times a week and also attend contests) fork over for a more expensive servo. Two big ones, the brushless motor and the all-alloy case.

So you have to look to yourself to assess your goals, needs, and budget because to the question; can I really use $50 servos and be happy? The answer is . . . yes, you can! Like if you’re a sport pilot, or one who doesn’t fly a lot, then it’s crazy spending more money.

But whether they’re the right servo for you, that’s an open question. And it’s one with only one answer . . . it depends.

So let’s look at what may be a better alternative.

Making the better-list are brushless motor, alloy case, plus longer servo arms. You’ll also notice we’re guiding you to a stouter rudder servo, too. This because now servos are getting more specialized.

Like eyeball the throttle servo, which at 0.05sec/60° is stupid quick! Why so fast? Simple, because now we’re speccing servos for pilots apt to be performing Harrier rolls, and other maneuvers requiring super fast throttle response.

With better, we’re getting into trick components.

Better

• Qty 4) DS505BLHV – 2 each for aileron and elevator
• Qty 1) DS630BLHV – rudder (more knife edge authority)
• Qty 1) DS255BLHV – throttle and (DS90DLHV if equipped with choke)
• Qty 4) PDRS45-25T arms (or PDRS35-25T if you detest touchy)
• Qty 1) PDRS50PP-25T pulley (pull-pull rudder, otherwise, a 5th 45)
• Qty 1) PDRS105 – arm (throttle and choke)

Pluses and minuses

So what do you get, what do you give up? To begin, the DS505 (along with DS630 and DS930) are BLS1-series versus DL-series.

No clue what the numbers and letters mean? No need for Cliff Notes:

So while you get all the goodness of a DL-series, the price is higher and you get something in exchange. This is what’s better;

• 4X more durable alloy case versus polymer
• 40% more torque in going from 360oz-in to 505oz-in
• 28% decrease in transit speed from 0.14sec/60° to 0.10sec/60°
• 5X longer motor life and cooler operation with brushless motor

. . . so first up, the case.

An all-alloy case

The case which is CNC-machined of 6061-T6 aircraft aluminum is simply more durable than the polymer case. If you favor thumpers, then these servos are a no brainer because the steel bearing securing the output shaft can’t deform it like it does a polymer case.

Know what else you get? Now the reinforcing bushings are steel instead of bronze because believe it or not, whilst lots stronger than plastic, aluminum is relatively soft. Especially compared to the steel gear shafts of the transmission.

So if you were to open a competing servo, you may find they took a shortcut. One, which you likely wouldn’t notice until after the warranty expired. Your money, of course but when they only show the outside of the product, you should maybe wonder why this is.

For example, we have matchUP articles on the site. Like this one;

• Futaba HPS-A703 versus ProModeler DS930BLHV

Theirs is $280 and ours is $130. Think this means it’s an unfair comparison? Nope, the DS930 upholds the family honor.

Like how we use bushings to reinforce the aluminum case while they don’t bother. Yet these servos, both, represent a significant investment. The use of bushing means a longer service life!

Anyway, this is what I mean.

40% torque increase

Next up, the bump in torque. Going from 360oz-in to 505oz-in represent a 40% increase. What more can you do because of it? Perform more aggressive maneuvers.

Granted, if you’re not into aggressive XA-class maneuvers like Crankshaft, then quite honestly, this doesn’t matter. But if you fly hard, then it does.

Allow me to bring up a servo for your consideration if you’d like a little more oomph. This despite the fact many pilots fly these servos in aircraft in the next class up.

DS630BLHV – 75% more grunt

So while we guide you toward DS505BLHV servos for ailerons and elevators, for rudder we point you toward the DS630BLHV, instead. Along with the DS505 and DS930, the DS630 and those are sister servos as alike as three peas in a pod.

What’s more, the DS630 finds a home in many larger models. I mention this on the off chance you get the urge to climb the ladder, size-wise, and repurpose your investment.

The major difference in DS630 vs DS505 is instead of a 40% bump torque-wise from the DS360, you’re now looking at getting a substantial increase of 75% more. And obviously, there are maneuvers where this added power is welcome.

For example, performing 800′ diameter knife edge loops. What else? Only you know, but for sure the price increase is modest by pretty much any measure.

28% quicker transit

One thing faster servos open the door to are maneuvers that require timing and quick response. The DS505 is significantly quicker off the mark to the tune of 28% faster than DS360. It’s noticeable in the air. If you’re a sport pilot, don’t waste your money. If you appreciate the finer things in life, these are just that, finer things!

Examples where the extra power is welcome include maneuvers such as Harrier rolls. This, because performing this complex maneuver sees you balancing the throttle, with rolling response of the ailerons, along with rapid and simultaneous rudder and elevator inputs. These all occur in a synchronized dance that has to be experienced to understand.

Faster is definitely helpful. And one thing is certain, the move from 0.14sec/60° to 0.10sec/60° is a welcome development for pilots. After all, what you never hear anyone moaning about are wanting slower servos, right?

Brushless motor

The last thing justifying a doubling the price for the DS505 vs DS360 is the brushless motor. Simply put these are the best money can buy. They run cooler and last 5X longer.

Don’t know diddly about the subject? Read up and learn more here:

• About RC servo motors

Bottom line? Facts are the ProModeler DS505BLHV is our top selling brushless servo because it’s so versatile it can serve in many models.

And it may be instructive to learn more about them by how we rebuild them. Follow this link to learn about the guts of this servo:

• On rebuilding damaged DS505s

Servos in the best-list are significantly FASTER; Like insanely faster. That, and the servo arms are longer still. Reason they’re longer is to obtain the crazy throw required for violent post stall maneuvers like Rifle rolls, Walls, etc.

Best

• Qty 4) DS635BLHV – 2 each for aileron and elevator
• Qty 1) DS845BLHV – rudder (more knife edge authority)
• Qty 1) DS255BLHV – throttle plus (DS90DLHV if equipped with choke)
• Qty 4) PDRS55-15T arms (or PDRS35-15T if you detest touchy)
• Qty 1) PDRS50PP-15T pulley (pull-pull rudder, otherwise, a 5th 55)
• Qty 1) PDRS105 – arm (throttle and choke)

ø6mm vs ø8mm

The DS635BLHV and DS845BLHV are two of a family of three servos designated BLS2. What’s different is they’re so fast we couldn’t offer them in a conventional ø6 output shaft with 25T splines.

This, because the servos were capable of ripping the broached splines from within the servo arm made of softer 6061-T6 totally smooth.

Almost as if they’d been hit with a 1/4″ drill bit. No, not kidding.

6061-T6 vs 7075-T6

So the fix was upgrade the from 6061-T6 aircraft aluminum to a harder alloy. So we began machining the arms of 7075-T6 (which rivals some mild steels in tensile strength).

But this created a new problem in that now the splines within the servo horn wouldn’t fail, but instead, the splined shaft itself would. Sigh.

So basically, these servos are so powerful and fast, they could then literally twist the 6mm diameter stainless steel output shaft if the arm didn’t fail. It’s always the next weakest link, right?

And no, we’re not kidding. Eyeball this.

Gnarly ø8mm 15T spline

So how do the two splines compare? This next photo shows two DS635BLHV servos, the earlier generation before we sussed out what was going on, the one equipped with the usual 25T spline (nominal 6mm diameter as used by us, Futaba, Savox, MKS, et al).

It sits beside the present iteration, the one with the gnarly 15T (8mm nominal diameter).

Note; we only supply the BLS2 servos with the larger spline now.

Anyway, we produce arms with splines broached for the ø8mm output shaft because had we continued producing these with 6mm splines, folks using them with ordinary arms made of 6061-T6 (as offered by competitors) created a recipe for disaster. After all, failure of the splines, even if it wasn’t our fault they weren’t using 7075-T6 because modelers are prone to using what they have on hand could result in a crash!

And for our part, the only responsible thing for us was to recall the servos, upgrade them from ø6mm to ø8mm spline (also requiring a new upper case section to accommodate the new larger bearing). There are no BLS2 with 6mm splines remaining in the wild.

So the funny thing is we brought forth something wholly new to the world performance-wise with the BLS2 series, and then at the same time, created a problem for everybody with 6061-T6 servo arms. Out new arms, made of 7075-T6 and broached for the gnarly 15T spline sorted the issue, perfectly.

Now let’s look inside.

5-shaft vs 3-shaft

Recapping, the BLS2 servos are so fast and powerful they can accelerate loads quickly enough to destroy servo arms made with 6061-T6 alloy. After learning arms made of 7075-T6 resulted in the output shaft twisting instead of destroying the broached splines within the arm, the fix was easy. We delved into the parts bin and adopted the larger spline from our Quarter-class servos (one ranging from 1505oz-in to 2685oz-in).

What’s more, when creating these servos, we abandoned the conventional 3-shaft design in favor of a 5-shaft design (internally). This is a 3-shaft design. Note how all 3 shafts form a straight line.

But while the hero in all this is the larger ø8mm output shaft because it lowered the pressure loading on the splines broached within the servo horns, the back story is the motors are what allows this to happen in the first place.

As a result of the magnets, we get incredible KV motors operating at incredible RPMs. To get useful work out of them we needed to reduce them (using gears) enough to allow them to live (e.g. stop rapid self-destruction under load). All whilst the servos deliver incredible performance.

Remember, at our core we have a belief in challenging how it’s always been done. In approaching things differently, we challenge the traditional ways of getting the job done. We do this by giving engineering a free hand.

Our innovative approach saw us abandoning the traditional 3-shaft design and opting to use a 5-shaft design, instead. And the only way to make this work was to adopt an S-shape, else the servo would get longer – meaning it would no longer fit a standard size mount.

Offset shafts sorted this. Look at this photo and note how they form an S-shape. This is the secret.

Faster, still

So when I say these servos are faster, I’m not kidding because the DS635BLHV transits in an incredible 0.042sec/60°. Put another way, while no slouch, the 0.14sec/60° of the DS360DLHV is 233% slower!

So because speed and power play a tantalizing role in certain maneuvers it means you must have both. This, because sans speed, you’re unlikely to perform the Rifle roll to the satisfaction of an XA-god. You need – both – power and speed. The BLS2 servos deliver.

However, straight up, if you fly IMAC, then the blinding speed of the DS635/845 are a complete waste of money. Honestly? You’re better off with the DS505 or perhaps DS630. Saying your wallet will be better off, capsici? But if you live, sleep, and breath XA-maneuvers, then accept no substitute!

And allow me to make an observation; if your goal is to step up from 25% and into 33% models, then because these use dual servos setups per aileron, then the four DS635BLHV used for aileron and elevators for the 93″ Laser 230Z are readily repurposed to the ailerons of the bigger bird.

Next, add one DS845 to go with the existing one used for rudder, and repurpose them to the elevators of a 120cc model. Finally, get either a single DS1155 or DS1505 for rudder.

And just like that, you outfit can a 33% model without having farted away your investment in servos for the 93″ model. Just saying.

Bigger gears

Anyway, the other distinguishing thing we did with the BLS2 series servos was go to physically taller gear profiles (internally). When the profiles are taller (or longer, however you want to reference it), this puts more gear face surface area to work.

This serves to lower the pressure loading on the gear teeth. Survival of gears is all about managing the loads. These steps sorted the issues associated with increasingly powerful servo motors nicely.

This is best explored with a photo showing a servo familiar to many, the high quality and very nicely made Savox SB-2290SG Monster.

Setup

So we began all this with a discussion about servos and setup. How with one model you could set up for IMAC, XA, or a model suitable for a novice to enjoy without getting overwhelmed by control surfaces so large the model becomes too twitchy and unflyable for them.

Servo arms

In our Good recommendation, we guide you toward 35mm long servo arms. In common with all thee recommendations, the horns are tapped for M3 mounting hardware.

But importantly, we give you many mounting positions. From 35mm, they step downward in 5mm increments ranging all the way to 15mm.

This presents an incredible amount of flexibility as moving the ball inward tames the model further and further.

Note the H-beam cross section delivering incredible stiffness. Also, notice they’re thick enough using a backing nut on the bolt securing the ball link becomes a thing of the past.

Our better recommendation sees us saying use 45mm servo arms. And our best is for 55mm servo arms. And here’s where an analog using good, better, and best falls apart. What we’re really saying is the shorter arms are going to be better to tame down the model.

However, depending on which IMAC schedule you compete in, they may have maneuvers require extreme throws, in which case the 45mm arms are great. But if your class doesn’t then stick to 35mm or maybe 40mm arms.

And for XA maneuvers? Then you want the longest we make. We guide you to 55mm arms but we also have 60mm if you’re truly insane.

Pulley – pull-pull rudder

This is where the magic happens.

And the benefit of the pulley for pull-pull control is unlike a conventional tiller arm where the non-pulling side goes a bit slack, the principle of the pulley keeps both legs taunt. The more perfectly you build your rudder pick up points (the control horns), the better. The goal, just as with a tiller, is for a straight edge between the two pick up points to be perfectly in line with the hinge line.

Since a pulley works rather nicely for cables, as shipwrights discovered centuries ago, why models reach for a tiller for this job is a bit of mystery. And yes, we offer tillers but their principal purpose is linking two mechanisms together, e.g. harnessing two or more servos together into a gang. But for cables? Pulleys are far superior for this job.

Pulleys are available from 34mm, through 50mm, to 100mm;

• PDRS34PP-25T
• PDRS50PP-25T
• PDRS50PP-15T
• PDRS100PP-25T
• PDRS100PP-15T

. . . the 34mm suited for models to 78″ and the two 50mm being great for 85″-95, and 100mm for models ranging from 103-126″

The 25T being suited for servos folks are familiar with featuring the nominal 6mm diameter 25T as popularized by Futaba. And the 15T being for gnarly output shaft as used in our BLS2 servos (DS635/845/1155) and Quarter-class servos.

Final thoughts

Allow me offer a few final thoughts. The right servo for you is a reflection of yourself, your goals, your dreams, and your budget. We put a better grade of servos in your hands. But nobody can make you buy them. This you decide for yourself.

Any questions? Feel free to reach out, we’re readily available;

• Telephone: 407-302-3361
• Email: info@promodeler.com

. . . maybe together we can suss out what’s best for you!

I’ll close with this, one thing’s certain, best is a race that’s never finished. Best right now? ProModeler, but far from David vs Goliath, we’re more akin to a flea on the elephant’s back in this battle.

Means we need your help. Presuming you like our servos, then do us the favor of taking one to a club meeting. Pass it around. Maybe even pull out a 1.5mm Allen driver and open it up – you’ve seen how they go together, there’s nothing to be afraid of. And please, show them to a pal.

But most of all, kindly grace us with a photo sharing your thoughts. What for? To put on the website, and within articles like this. Basically, for telling the next guy what you like about our servos.

We’re Jones-ing for photos like this one because your favor is priceless and can’t be bought. We know this. So do others.

Last thing

Have you enjoyed this? If you like reading and are interested in learning more, then maybe find time to review more articles like this;

• On the batteries John prefers using
• About pots vs Hall Effect sensors
• On selecting battery packs
• Pro tips for improving your ARF
• Amazon servo vs DS505s
• Why’s my pack got two JR-connectors?
• Rip Van Winkle, on returning to RC
• How to guide a rocket using servos
• Phoenix Models 70in Strega guide
• Advantages of pull-pull via pulley
• Bret Becker: Mr. Top Gun
• Will ProModeler servos work with NiCds?
• How to determine flight time for a 2S850 LiIon
• Hangar 9 60cc Pitts S-2B servos
• Fear of loss, or how to stack the odds in your favor!
• When LiFePO4 is mistakenly charged as LiIon
• Idle thoughts regarding chargers

. . . and hundreds more. Best part? They’re all free!