Review: Aeroworks 122″ YAK 55M
This showed up at my place yesterday, and it is pretty sexy, I must say:
The plane really looks great, amazing actually. I’m in love with it. haha Very cool looking plane, for sure. I’m always thinking about weight, though. I just finished the Hangar 9 Sukhoi review and that plane is light and flies light. So, I started making some comparisons. The wings on the Aeroworks are larger. They’re longer because they go into the fuse. And, they’re about an inch wider through the cord. The shape and design is very similar. I thought the Aeroworks look even more small-pattern-wings in the pictures on the Aeroworks website. But, the wings are slightly less patterny than the Sukhoi and also the ailerons are closer to the root which makes them larger overall. By all rights this plane should fly good. So, anyway, the Aeroworks wings are longer and wider, but also weigh 2-5/8 ounces more (each wing weighs 2-5/8 ounces more). Oh, that would be 3 lbs 5 ounces for the Sukhoi vs 3 lbs 7-5/8 ounces for the Yak 55M. That’s not a lot, in a 40% you can always deal with a couple of ounces.
I don’t have fuse comparison weights, but might be able to work that out with Nolasco who also has a new Sukhoi. But, for now let’s say the AW fuse weighs a pound more, because it does feel heavier (there appears to be more wood in there). That’s 16oz, then 5oz more for the wings… that’s 21oz. But here’s where it gets interesting. I had a feeling that the Yak 55M main landing gear was going to be light. It is.
It weighs 12-3/4 oz. Compare that to 31 ounces on the Sukhoi. The main gear alone makes up for 18 of those 21 ounces.
Then there is the tailwheel, and Aeroworks has always had super light tailwheels. It weighs less than an ounce:
The wheel pants are a 1/2 oz each lighter. The Tires are about 3 oz lighter each. That’s another 7 oz. So, stock to stock, I could easily see the Yak 55m coming in exactly the same weight as the Suhkoi. Which I would be very happy about. I’ll weigh them both RTF when the Yak 55m is assembled.
I’m going with a DA-170 on RE3 tune pipes again because… well?… did you watch the videos? haha The engine makes tons of power but what I love is the sound of those pipes! So sophisticated! I do like the sound of the 3W 170 on Pefa cans, but no one seems to run 3W anymore? I hear about ZDZ, DLE, and GP, mostly. DA is USA made, which is cool. I need to check and see how much of the engine is made here for general interest. I saw a video where they are making the cranks right there in the shop. I know they get the ignitions from Australia. But I can’t believe, after all these years, I don’t know if the rest of the motor is made in-house, or not. Either way, I’m very happy with my DA 170 on RE3s. It has been a runner from the first start and it just sounds so good!
I’m thinking about JR servos this time (Hitec is still backordered on the Brushless servos for a couple of months). Maybe the:
JR MPH83T MK II Linear Hall Sensor Brushless Torque Servo that Tavis likes so much.
Specs are:
563.8 oz-in @ 7.4V
0.13 sec/60 deg @ 7.4V
Linear Hall Sensor (instead of a potentiometer)
With 563.8 oz-in along with the brushless motor holding power… maybe just one per elevator and two per aileron.
About the plane… pictures don’t do it justice as of yet… the fuse is just a beautiful thing in person.
I popped the hatch and the intention becomes clear. Sculpted roundish fuse, bracing, and mostly sheeted. This is really more of a custom kit built in China than what you think of when you say ARF. it really looks like it would go 10 seasons with no trouble at all, as well.
The RX tray is removable, I guess to access pipes, if you have them?
Check out all that sheeting and bracing! And, the strings for the elevator servos, nice:
There does seem to be a pocket in the tail for push/pull rudder servos:
Trying to get a shot that shows that rounded fuse:
Okay, well, even though I’ve seen these water bottle tanks for years and had them in my 3W planes… I never got around to getting a PSP water bottle fuel tank. I tried one in my Sukhoi and it’s working great and is 3oz lighter than the included tank. First thing you have to do is get some water from the store and drink it. I put Monkey on that:
Didn’t take him long to put the kit together, either. PSP has a video showing you how it’s done:
Anyway, Monkey didn’t really let the bottle dry out, we’ll have to address that:
PSP sends along Viton with the kit for the carb line… seriously good stuff.
Here’s how the kit arrives:
Here’s what’s included:
Okay, got started on the hinging tonight.
I’d have to say, if a guy isn’t really prep’d and organized… along with being super fast… 30 minute epoxy on the ailerons hinges, both sides at the same time like the manual shows… is a challenge. For doing the aileron and wing at the same time the longer working time of gorilla glue might be better. Even 10-15 minutes of working time would be fine. But, 30 minute epoxy has always given me 3-4 minutes, max. I did the first aileron the way the manual suggests and I would not try that again. haha
The good about doing the hinges yourself:
Hell, four minutes and you’re done. 🙂
The bad about doing the hinges yourself:
Hell!!!, four minutes and you’re done!!!! :O
However much you can get done in four minutes, that’s what you’re left with. haha I think I’ll have a stress free, casual time, doing the hinges with 30 minute epoxy the way I always have. The surfaces first, then after they setup, put them in the plane. Anyway I made a video showing the wing after I glued in the hinges:
Dropping back a second… I did finally get my hands on some Super Lube! haha I’ve used this stuff for years (don’t say it!), and was glad to get some more vs using Vaseline. Using Super Lube just sounds a lot cooler than using Vaseline! I spread a healthy amount over the hinge knuckle and also work it into the hinge pretty good. The reason I do this is to keep any epoxy from sticking to the hinge knuckle.
I’ve talked about this for years in these reviews, I always recommend bamboo skewers from the store rather than round sticks from a hobby source. The bambbo skewers are like 1/10 of the price!
Just did a quick google search and only found one 60 minute epoxy:
http://www.amazon.com/Loctite-1405603-F … nute+epoxy
In the Q&A a guy asks how much working time he’ll actually have. One guys says 4 minutes, another guy chimes in and says probably less than that. haha
Okay, the JR servos showed up today. The wing hardware that Aeroworks includes in the QB is in the background. AW gives you steel pushrods with a tool, quality balljoints and quality nuts and bolts. AW uses these pushrods and the plastic Hitec servo arms that come with the Hitec servos with no problems whatsoever, and AW test pilots fly their surfaces harder than me, for sure. But, for me, I’m going with titanium pushrods and all stainless steel nuts and bolts from www.microfasteners.com . They clean up easy and look real nice. Looks like 3″ is the right length on the pushrods (I’ll verify that later during the installation) and I have those in standard H9. I’d like to get them in blue from Team Associated, we’ll see if that gets done. haha Also I think the DUBRO blue ball joints will look cool, so I am going with those:
I’m using the included AW control horns because I like the way they spread the load out over the hard point. I like a single bolt better, but I’d have to put in my own hard point to be sure if I was going to use a single bolt. And, again, that is the wrong length blue pushrod, but I want to go blue if I get around to it. haha
Okay, yeah, so I walk in after dinner and Monkey is all, “Wtf did you do to the plane?!” And, I’m all, “Ah geez, you’re kidding me man!”
So, Monkey says, “What the hell did you do?!” And, I’m all, “What the hell did =you= do?!”
Then he admits it, he was trying to pull off the black checks on the back of the wings and all hell broke loose. Turns out AW really irons the covering down bombproof style now. Lapped covering and leading edges of the wings have the covering pretty much permanently attached. Don’t even try to take any covering up unless you’re ready to recover… Monkey will tell you! So, Monkey says, “Don’t start throwing poop around, I’ll have this recovered in a flash.”
“One thing, Joe, where in the world is my pen?”
Thing about Monkey that you have to understand… he’s a frustrated builder. Add to that his duties “on the bag” (protecting my Taylormade driver for the last eight years without so much as even looking at a model airplane), and you have a monkey on the loose situation, you see?
Thing is, he’s still got it, so I guess it’s all good. Only took him about an hour to make things right. He knows these stripes are easier for me to see in precision rollers, he was just trying to help me out, is all.
And, the bright side is that I get to show you a few things about how the plane is built, and also I get to thin CA the hinge balsa blocks.
This first pic not only shows the materials, design and workmanship, but also probably shows why these wings are 2-1/2 oz heavier than the Sukhoi wings (other than being larger). They are built as strong at the tips as they are at the point the wing tube stops. The spar stays beefy all the way out to the tip. There’s no flex in these tips unlike my Sukhoi (not saying there is anything wrong with my Sukhoi, it flies totally awesome). Again, this plane just looks like it will hold up to many years of flying.
Look at that balsa, like a high quality kit:
Balsa hinge blocks, I poured a few drops of thin CA on these as long as I had the covering off:
The hinges toward the root get less and less penetration into the wing:
The last hinge on the root side gets about 1/2″ of penetration:
Some tips and tricks on hinging the this particular (and recondite?) model:
Took care of the other wing and changed the black stripe on top to blue.
Okay, some good and bad about the hinging. One thing I want to make clear is it doesn’t take any time. 14 years ago on even the nicest ARFs you had to cut your own hinge slots. And, then glue them. Here you only have to glue them in and that does not take any time. If you glue the surfaces first, like I do, and then let them setup before gluing them into the plane, it is also easy work. So… fast and easy. Also, I’m getting 65 degrees of travel up and down on the ailerons. So. that is nice. If I were to cut the slots deeper I could get even more, but I probably won’t use more than 50, or so.
Couple of things I’ve discovered though, there’s a small refinement that might make it possible to have the hinging come out absolutely perfect. Mine is not 100% perfect. I have 65 degrees of travel but I have a slight binding past about 30 degrees. I believe two things are causing this and the main problem I believe can be avoided quite easily during the gluing of the hinges. So, I think I have a slight binding that will go away with a little hinge stretch (not ideal). And, I think I can keep you having much, if any, binding. I’m going to try it out on the elevators, but that will still not be an apples to apples comparison. If any of you want to drop by Costa Mesa with your wings I will glue in your hinges for a scientific comparison. haha
So, first thing that I wonder about would really need to be a small factory refinement (and may or may not be a big deal because of how short each pin is). But in this drawing you can see that the hinge pins are all at a different distance from the wing. They are parallel to each other but on different planes. The hinge pins are not in a line with each other. A factory refinement could have the jig for the hinge hole drilling setup at a slight angle so as to have all the hinge pins in a straight line:
Currently:
Possibly better:
Okay, but here’s what I speculate is the crux. And, if I’m right I’m kinda mad at myself because this is what worried me when I first went to glue in the hinges. I looked at the job, then looked at the instruction manual, then said to myself, “really?”. I then called Rocco for, and I quote, “some criteria” haha, on how to put these things together for a perfect result. You know, what are the determining factors? Anyway, what I saw was the slots were cut out into balsa, and that balsa is a soft wood and these were big slots. In my mind, no way could I just push all the hinges down into that slotted cavity and have all the hinge pins line up. Sure if they jig drilled into a more solid surface I could do that with a precision result… but not a big slot into soft balsa. It was Friday night at 8pm and for some reason Rocco didn’t answer the phone. haha So, I just decided to do it like the manual showed. “It’ll be fine” I said. haha Well, imo, do not do it like the manual. First off, unless you’re really good, fast, and organized, you will not have enough time to get all 12 of those hinges in. Second, I think I have a better way.
I already talked about gluing the hinges in the ailerons first, letting them setup, then gluing them into the wings. That is fast and easy. All good, except I still had binding past 30 degrees of travel. Why? Maybe partly due to the hinge pins not being in a line, but I speculate mostly because of the slots in that balsa that I was concerned about from the start. I had an idea. And, I think if I had another set of wings it would be even more obvious. But, I grabbed an elevator half. I put the hinges in, and just as I suspected all along, they do not finish in a line. You see I tried to use a straight edge to get the pins in a line on the first aileron hinge gluing I did. But, because of the pocket you can’t do that. The pocket is in a U or V shape and doesn’t allow you to see the side of the hinge pins to line them all up. But…. but…. if you don’t do it the way it shows in the manual (of gluing it all together at once)… and you glue the aileron first… then you can use a straight edge to line up the ends of the hinges. That will line up the hinge pins!! If you hinge per the manual your hinge pins will not be lined up. Again, that was my initial fear and I’m mad at myself for not working it out before I started gluing. I never used to look at manuals, I’m getting old. haha
Here is a picture of the hinges pushed into the elevator… when the straight edge hits two of the hinges the others are all short of hitting the straight edge. Meaning the hinge pins do not line up. You know that ain’t good!
I’m going to try my theory out on the elevators (that even with the hinges installed dry still had binding, which would make sense if the pins are not lined up, we need to line them up I think), and report back. I speculate that the following method will be good for getting a decent result with these hinges.
Glue the control surfaces first and let them setup before installing them in the plane
1) Lube the hinge with a thick coating of lube
2) Glue the hinge in to the control surface
3) Twist the hinges to align them until they move freely full travel in the slots
4) Use a straight edge to line up all the ends of the hinges (if you shaped some upholstery foam to keep the hinges all straight out, but on plane with each other, while doing this… all the better)
4a) Square up all the hinges to the leading edge of the control surface
5) Let that setup
5a) After the glue has setup on the elevators, clip an 1/8″ off the end of the two inboard hinges (I dry fitted fine here, but after I aligned the hinges with the straight edge I was not fine, had to make a quick cut during gluing)
6) Put glue in the wing (or stabilizer) holes
7) Take a paper towel and denatured alcohol and wipe off any glue around the holes
8) Put glue on the hinges and push the hinges into the wing
9) Put in the card stock shown in the manual, and even then have the card stock in there pretty loose
That might be about as good as can be done with these. I’ll try it on the elevators and report back. It’s more critical on the wings, though, as there are 12 hinges across a long aileron. Plenty of opportunity for hinge pins that don’t line up. But, I think this method will provide a decent result.
Okay, 100% success with the elevators with this method (slot end to slot end with no binding, over 60 degrees of travel):
Glue the control surfaces first and let them setup before installing them in the plane
1) Lube the hinge with a thick coating of lube
2) Glue the hinge in to the control surface
3) Twist the hinges to align them until they move freely full travel in the slots
4) Use a straight edge to line up all the ends of the hinges (if you shaped some upholstery foam to keep the hinges all straight out, but on plane with each other, while doing this… all the better)
5) Square up all the hinges to the leading edge of the control surface
6) Let that setup
7) After the glue has setup on the elevators, clip an 1/8″ off the end of the three inboard hinges
8) Make sure hinges go stop to stop without any binding. Clean out glue and/or wood until there is no binding.
9) Put glue in the wing (or stabilizer) holes
10) Take a paper towel and denatured alcohol and wipe off any glue around the holes
11) Put glue on the hinges and push the hinges into the wing
12) Put the card stock in loosely or use two pieces of card stock
STEP 4
STEP 5
I have a lot of posts on the hinging of this plane at this point, but I think anyone who gets the plane is really going to appreciate the above 12 step program. haha Here’s a video of the elevator after the glue set up:
I started working on covering the top of the wing that… cough… Monkey screwed up.
All finished up. I told Monkey, “And, do not do it uh gain!”
Something just showed up at the door… wonder what is inside?
Whoa! I didn’t see that coming! haha I didn’t even know Monkey was in Colorado! Says he was helping Rocco get all the cowls ready to ship, that’s his story anyway, who knows what he was really up to? Monkey business, no doubt!
At least he did manage to bring the cowl back with him!
Look mom! No visible mounting screws! Nice!
except for four underneath.
You gotta see this thing in person… it does not look like an ARF… it looks custom. I can’t say how it will fly, but I love the way it looks. I’d be very proud to have it at an event, etc.
I like the landing gear concept. You might call it a shear connection vs a stacked connection. Normally the plane would be stacked on top of the landing gear, but in this case the landing gear it bolted to the side of the plane. That does a couple of things. One they are lighter. The other is that it requires less angle on the gear so theoretically a stronger angle.
The covers are very nice and they lightened them up with some holes:
When you bolt on the landing gear, don’t tighten it up all the way until you dry fit the covers. The covers fit snugly around the gear so you have to line the gear up for the covers or the covers won’t fit on right. I found it easier to flip the plane over to put the covers back on.
I bolted on the stock axles, wheels and spats:
I did change the set screw to a socket head style. Much easier to deal with and not have strip out.
Oh, and also the screws for mounting the spats… I changed them to stainless steel with stainless steel sealing washers:
I bolted on the stock tailwheel… they are very light, less than an oz:
I changed out the stock phillips head screws (they would work, but I prefer not to push on the plane when putting them in and/or removing them, and that is what you have to do with phillips screws) to a socket head screw. You could even go to a 6-32 socket head, I believe. But, I ran these in, then took them out, put some thin CA down the holes, let it dry, then put these 3mm servo screws in there and it felt solid.
The cowl is crazy custom cool with its interlocking stout tabs with only four screws visible on the bottom of the plane. The fit on mine was perfect:
Ordered a 4″ TruTurn P-51 spinner with a Menz cut:
Nolasco @ P1 Hobbies got me some graphics today. Here’s the first one I applied:
Here’s a Fromeco sticker Nolasco sent me:
Well, a fellow Hitec user wanted me to have a chance to compare the Hitec brushless to the JR brushless… so I was able to get these servos (I’ll be trying these first and then the JR brushless after for a comparison):
I tried to decide if I was going to use any electronics that would be incompatible with the regenerative braking that these servos have. Not being certain I decided to use a PAD (power absorbing device) on each servo. I always solder my servo leads to my extensions anyway, so it wasn’t much extra work to attach the PADs right there at the splice:
Rumor has it these servos have serious power, so I bolted them down with 3mm x 5/8 screws:
I’m also thinking of going with ultra HD DUBRO 10-32 control horns:
I did my usual and soldered Dean’s ends onto the servo extensions. Nice grommet Rocco has setup for your servo extension ends:
Nolasco made me up this DA sticker, as well:
I drilled a hole, dropped 6 drops of thin CA in the hole (let it dry), and then epoxied in the DUBRO 10-32 control horn bolt. This setup, with the end points in the transmitter set to maximum, got me 55 degrees of deflection each way off of center.
I don’t think I’m going to use a non brushless servo ever again, in any plane. And, that’s about all I have to say about that. haha
I used a protractor to adjust the height of the outside control horn to match the inside control horn. You want the pivot point (ball joint) the same height above hinge. Owing to the tapered wing that will be a different height off the control surface. In this case approx. 1/4″. With finely adjustable height control horns, like these DUBROs, you can get that exactly right. I don’t try to measure from the hinge (nearly impossible on this plane, btw), I use the protractor to adjust the horn height until the servo arm travels the same distance each way off center (in this case 55 degrees each way) for the surface to travel the same distance up and down off center or neutral. So, in this case (which is pretty ideal as it turns out) the inboard servo ended up moving 55 degrees each way from center to have the surface move 55 degrees up and down from center (on the AW throw meter… although I actually set this stuff up with a ruler). Now, this was after I adjusted the pushrod length on the inboard servo until I had equal travel on the protractor matching equal travel on the surface. This will not leave the servo arm at 90 degrees to the servo body unless 1) the control horn pivot point is EXACTLY over the hinge line, and 2) the servo body is EXACTLY perpendicular to the hinge line (and in this case the servos are perpendicular to the leading/trailing edges, and the hinge line is not parallel to that line). Downside to that 90 degree setup is lack of travel due to the control horn hitting the surface.
Then from there I use the protractor to find the to be determined center point of the outside servo, then adjust the control horn height until the surface travels the same distance up and down from center as the inboard servo does. So, again, the protractor showed 55 degrees of travel from center each way, to have the surface move 55 degrees up and down. At this point the servos are going to be matched perfectly throughout their range of travel. And, once you copy this to the other wing… then you always know that any deflection up (say 20 degrees) on one side of the plane will be matched with the same deflection (20 degrees) down on the other side of the plane.
Now, I have to say, that I speculate that the included AW control horns will last longer than the plastic part of the DUBRO horns. And, also say that the AW control horns are adjustable height. And, that even though their adjustment is more coarse, it is within reason to set this all up the same way I’m presenting. You could even get a perfect result by sliding one hard point left or right until the protractor tells you everything is even up. The main reason I am using the DUBRO horns is because I felt like it. haha I’m a modeler, modeling is fun to me, and the idea of using them and of just modifying planes in general, is fun. I might not even use the DUBRO horns on the elevators. haha
Also, another point, the control horn distance from the leading and trailing edges will be different between the inboard and outboard servo because the hinge line is not parallel with the leading/trailing edges on this particular model. So keep that in mind, too.
WTF is this? :O haha
Monkey was telling me he’s out of everything, so I told him to go online and order whatever he truly needed. He says he did:
Well I’m gonna compare the Hitec brushless to the JR brushless, so might as well compare the DA 170 to the 3W 170! I’d like to compare the Futaba and MKS brushless servos, too. I haven’t found anyone who has run all these servos and actually knows how they compare. I’d like to compare a ZDZ 180 to these two motors, too! Usually most of us get happy with one brand so don’t want to chance, and don’t have the time and money, to try everything that’s out. But, it would be fun. haha I don’t know if I’ll run this 3W on this Yak55M, or not. I could put it on my Sukhoi, or a new plane… I’m thinking.
Now this vinyl I like! Nolasco finally got one right! haha Monkey approved!
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I was asked on www.giantscalenews.com about a comparison of the quality of this plane versus the quality of other brand Yaks… I’m speculating the comparison was requested in order to justify the Aeroworks costing more than other brand Yaks. I replied:
Yeah, maybe the powers that be are more open to those types of discussions here than on www.flyinggiants.com , I don’t know. It’s a small hobby, especially in the 150cc size. It reminds me of that documentary Mondovino. And, also of Robert Parker (same industry). You have these generations old wineries in france, etc. With one word from a published expert they can be helped or destroyed forever. Still we’d all like to know how all the rc plane products perform and also know about their quality. We’d really like the unbiased straight story. But, it’s tricky… definitely a slippery slope. We don’t want to put any of these guys in peril as we need all of them. There’s not that many choices now. It’s a hard business, again, we need these guys. Or we’re going to be building kits again. :O lol Also, price and value are totally relative, totally your perspective. There are china ARFs on eBay for great prices… there are composite planes internationally that are very expensive… there are average priced USA companies china ARFs… and higher priced USA companies china ARFs. And, man, if you want great bang for the buck, some of these used planes are real steals. Then you might want some service and support. That ranges from okay to great. I haven’t purchased one of those eBay planes but there is probably no support there.
As for this AW Yak55M… I just put together a Hangar 9 Sukhoi (which I have 36 flights on and totally love, just a great great plane)… and it is clear that this AW Yak55M would cost more to manufacturer. Just the double wall round sides alone is twice as much work. The cowl is twice as much work. If this plane looks good to a guy I would advise him to get it (it’s not like it is high priced like a composite plane or anything). If that same guy wanted to get in as cheap as possible I’d tell him to get one of these used engines online (just saw two DA-150s go for $400 a piece) and there are amazingly good and strong servos for $100 (I see used 7950s for $70, too). For the guy that wants it all, get a highend new engine and some brushless servos! Either way the price of the plane won’t change the budget much over the average priced 40% plane. That’s how I look at it, anyway. But, we’re all going to have our own perspective on it.
I just looked up at your quote… “same plane/different brands”. I don’t feel like this plane is same plane as the other wooden china ARF brands. It’s more custom. I’m not saying it’s better than anybody else’s ARF. I’m definitely not saying it flies better, I still have not flown it. haha I’m not saying it’s worth more to everyone. There is more to the cowl and fuse than I’ve seen on other aerobatic ARFs. I really think if you want it, get it. If you don’t, don’t. “You” being second person plural. I don’t think the fact that it costs more than average is going to make a difference to a guy that likes the look of this plane for its appearance or for the guy’s style of flying (it is designed for precision, although from the videos it clearly can harrier roll down the runway, haha). Reputation will probably come into play too… if it starts winning IMAC events, all conversation will be over, and it will sell out. haha
Off topic: haha
I just wanted to talk about Kurt @ Fromeco. I just got off the phone and he said, “Now I’m going to have to smack you around.” haha Deal is, I’m ordering some switches from him for, hopefully, this plane. His switches have a higher throughput than most all HD switches (I normally use an electronic switch to a power expander) because they are electronic switches. So, I am always trying new things and wanted to see if I could get enough current to the servos through two RXs without a power expander. I thought if I had Kurt solder up some switches with 3 RX leads it could be interesting. So, we’re BS’n while he is soldering these things up and he’s cuss’n at me because there really isn’t enough room to solder 3 leads on the switch neatly. haha So, I say, “You know what? If you just send me some normal ones with two 16gage wires out to a Dean’s end (that’s standard), I’ll make a pigtail with a Dean’s end to 3 RX leads.” And, that’s when the fight broke out. haha He says, “I just finished these and you’re going to run them.” Now Kurt is pretty big so I will just be doing what he says. haha
But, what I wanted to talk about was when I went to the Pacific Coast Freestyle Championships without a plane, a few years back. Kurt had this awesome 3.3m monster CompARF Yak. Very big, very expensive, and it was Kurt’s baby. It was mint, too. So, Kurt offers to let me fly the plane in the freestyle against Kyle Woyshnis and the boys. After the first two rounds I’m in 4th place out of like 7 guys. Kurt comes over to me and says “what’s the problem, is it the plane?” And, I said, yeah, in a way. The plane is so nice and I don’t want to hurt it. Kurt says, “Hell, fly it like you stole it! Planes go in, I’ll just build another one. Don’t even worry about it!” So, I go on to have the best contest flight I’ve ever put up and finish 2nd to Kyle. Second place was like $800. Anyway, Kurt is pretty cool, I’m just saying.
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I started in on the engine spacer. This is the longest one I’ve made… 2-3/4″. Here is twelve pieces of 1/4″ aircraft plywood rough cut. I actually only need eleven so one will get tossed. I still have to lightening hole them all and drill the four bolt holes in all of them. Then I’ll epoxy them together, grind that hunk down with a drum sander, and finally seal it.
These 4-1/4″ long bolts are not going to be long enough to get a nut on the other side of the firewall. I’ll need to order some 4-3/4″ 1/4-20 bolts.
I got back to working on the engine spacer. I used a 2″ holesaw and drilled holes in all eleven plates. Then I epoxied them together, ran the engine bolts through (that I coated in teflon lube) and clamped the whole mess down tight:
While that was drying I glued in my rudder servos. I did the 12 step program and they came out perfect:
Previously I had put the control horns on the rudder. I wanted to put the DUBRO 10-32 control horns on the rudder like I did on the ailerons. But, again the hinge was in the way for that type of horn. And, I already know I am fine with the stock AW horns, so I just used those. Last one of these AW planes I assembled I did the stock pull/pull setup per the manual and the geometry came out perfect. So, I’m hoping that’s the case here too.
I put the stock AW controls on with black servo screws, just cuz I thought they were cool. haha I did put thin CA down each of the holes to soak into the balsa before I put the screws in. The screws had a real solid bite.
Finally I got back to the engine spacer. I started sanding on it for a few minutes with a spindle sander and then called it a night. It took an entire 12″x24″ x 1/4″ piece of aircraft ply to make this spacer. That sheet weighed a ton. After I got the eleven plates and drilled out the 2″ center hole, and glued it all together, it weighed 11oz. I’ll get it down to 8oz or less with the spindle sander. Still half a pound, but it sticks out 2-3/4″… so it’s just big.
Biggest one I ever made. haha
I called it at 8oz. I could probably make it 2 oz lighter, but it’s so tall. For all the time I have into it Monkey would definitely get upset if it were to crack because I made it thinner. I can live with 2 extra oz.
Next I downloaded a template for the engine and transferred that over to the universal wood template AW includes with the plane. I then taped that on the motorbox while lining its alignment lines up with the alignment lines on the firewall. Then I drilled it out for the blind nuts.
After I put in the blindnuts from microfasteners.com I used ZAP thin CA on all the glue joints I could get to throughout the plane. I used to always get my ZAP glue directly from Frank Tiano of ZAP glues because it always came so fresh. Once when I got some CA from a hobby store it was so old that it could not glue two pieces of wood together (literally could not). My local hobby store says they get fresh glue in every week so I went ahead and got it locally this time.
I put the cowl on and the engine was nice and centered:
The H9 Sukhoi pilot is cool and comes included with that model. It weighs 7oz. I really like this AW pilot, and it weighs about half that at 3.8oz. Although it does not have a face, poor thing. haha
Somehow I forgot to show the engine mounted.
I used 5″ bolts, although 4-3/4 would be perfect, and 4-1/2 could have worked in a pinch. I had 4 and 4-1/4, but neither were long enough to attach a nut on the other side of the blindnut.
The Walbro carb has a short throttle arm with bad geometry to get any kind of proportionally linear transition of the engine. Here’s some pics of a similar carb in a previous review I did where I show what I did and why:
I didn’t have any more of those nifty old Nelson arms lying around so I used the included 3W arm. I soldered and bolted it down:
I cut in the throttle servo pocket, glued in some hard points for the servo screws, drilled ’em, put thin CA in them, and then bolted down the throttle servo. I used the stock throttle servo arm (4-40 piano wire), so I used a carbon fiber sleeve over it. I put some epoxy inside of each end to keep it from moving. Normally I’d just use a 6″ titanium turnbuckle, but I didn’t have one laying around. I used a stock plastic 3/4″ long servo arm from Hitec. I ended up with the sub trim at 0 and end points at 130/130. That should give me the kind of resolution I like. And in combination with the butterfly/throttle linkage being correct… I should really have a nice throttle response.
Also, you can see that I covered the sides and bottom of the motorbox and painted the engine spacer grey. Not seen is that I soldered on a PAD and an extension to the Hitec brushless 9465 servo that I used for the throttle, it has a .07 speed.
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I was asked this question on www.giantscalenews.com: I have only heard of using aileron differential to help with yaw while rolling. Now I am wondering if it might be part of poor geometry. If you did use differential, would you still keep the neutral point of the servo centered so you had equal degrees of throw and just move your horn location to get the differential you want?
I responded: When trying to achieve axial rolls you run into problems if you have an aileron on one side of the plane with more drag than the other. You won’t feel it on roll rate, it will still roll at whatever rate you want by increasing or decreasing the overall roll rate. IOW, you can still roll with just one aileron working and the other fixed. But, the drag is heavy on one side of the plane and there is no drag on the other side. That’s when you start wobbling around. Prior to working on geometry I had that effect all the time and would work on the radio to tune it out. And, also later with the CompARF with skinned hinges… one side always had more drag because the hinge line was not in the center of the wing. Aileron differential just means the ailerons are moving a different amount. Aileron differential can be used to avoid manually coordinating a turning maneuver, but I only used it to correct (as you suspected) bad geometry. I used the radio’s aileron differential mix to remove the plane’s aileron differential.
As to the servo linkage setup, yes you can either set it up for equal travel with the servo as shown in this thread (no differential), or set it up without equal travel and then you will end up with differential. Different rates and speeds, as discussed. You can then use your radio to dial out the differential or leave it in if that’s what you (2nd person plural) want… e.g., if you want it there for coordinated turns. In IMAC and Freestyle we don’t actually do a lot of turns. I’m more concerned with axial rolls and rudder coupling. I pretty much thumb it from there for IMAC or Freestyle. But, talking to Jason Shulman back in like 2002… he told me he mixes the hell out of his planes. I’ve never taken the time to really tune a plane with a radio. I like to setup the linkage where the geometry is perfect, that gives me axial rolls. From there I do a rudder to elevator mix and a rudder to aileron mix and call it done. Sometimes for IMAC I’ll do a low throttle tuck (low throttle to down elevator mix)… but usually I just thumb that, too. haha Hell, my friend’s tell me they can fly 3D in my IMAC rates, haha, and I run little to no expo in 3D rates (sometimes positive expo). But, I’ve never talked about radio work, because I can’t recommend mine, it’s just how I like it. I talk about geometry because that’s an absolute.
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Well… I was looking at the access hatch on the top of the motorbox and thinking how I’d prefer that area solid. So I took out the screws and epoxied the hatch in place. Then I covered the top of the motorbox for fun. After that I finally quit screwing around, haha, and got down to doing some standard assembly items.
I mounted the ignition (leaving an 1/8″ gap underneath most of it for air circulation). You can see a couple of extra leads coming from the ignition. Those are for an optional LED light and an optional tachometer.
Next I installed the fuel dot. I had a couple of other fuel dots laying around (and there are several nice ones out there these days), but I chose the JEModel fuel dot that Aeroworks sells because it’s smaller. And, with the round fuse any large flat plate bolted to it is not going to look very good. I made this backing donut for it, because the sides of the fuse are balsa.
I made some hard points for the Fromeco Badger switch, as well:
After that I mounted the ignition battery.
I have always used “nasa” foam, but have been reading that it hardens in cold temps. It’s pretty mild here in California, but I thought I’d go with DUBRO foam from now on.
I’ve always soldered on Ultra DEANs to the battery leads. I never worry about them coming loose. But, in this case I thought I’d try the Aeroworks Safety Clips:
In this pic you can see the engine mounting bolts. I epoxied the blind nuts in place. Then used blue thread locker on the blind nuts. Then blue thread locker on the standard nuts. Then blue thread locker again on the nylon insert lock nuts.
As you can see in these pics I plumbed up the PSP Manufacturing fuel tank. I like to use 1/8″ line to the fuel dot (so it doesn’t start getting loose), and 5/16 line to the carb. DA says 1/8″ is all you need with this size motor, but I’ve always used 1/8″ for 100cc and 5/16″ for 150cc. So, 1/8″ to the carb is probably great, but I’m still going 5/16″ out of habit. haha
Aeroworks has these vent dots, so I thought I would try one. I didn’t attach it with CA like its manual shows. I used epoxy in hopes of having it be maintenance free.
These carbs are sent out with the fuel intake pointed anywhere but at the fuel tank. But the pumps are strong so I just plumbed it up. Had to drill a hole in the snorkel to keep the fuel line away from the mufflers:
This morning, labor day morning, I sent an email to Aircraft International asking about it, out of curiosity. I didn’t expect to hear back on a holiday. But, Gerhard replied back in minutes saying they do come that way from 3W Germany. But, he said that you can carefully rotate them. I tried but didn’t think I could get it to rotate without breaking it. I emailed Gerhard again and he replied saying that if I wanted to try harder and ended up breaking it he would send me a new all steel after market fuel intake nipple. I then had the confidence to go ahead and turn it. It turned, thanks Gerhard!
I love the look of this plane! So aggressive! Ready to F”n go, man! haha
This is the first time I tried Rocco’s “the ol’ use card stock 4/40’d to the cowl mounts for marking muffler holes trick” (I usually run cans). It worked like a charm. Also, I don’t know what you guys use to cleanup unwanted CA, but I’ve been using Hot Stuff wince 2001 and don’t know what I’d do without it.
4″ TruTurn P51 spinner with lightened backplate and Menz 32-10 cut:
Got the elevators done. With this setup my servo arm moves 55 degrees each way from the TBD center, so that my elevators move 48 degrees up and down on the AW throw meter. My radio end points are set to 130/130. So, I have pretty much maximum resolution. I used the 1-1/2″ hole location on the servo arm because with only one elevator servo per half I wanted to be at least somewhat conservative. I can get more throw, up to 60 degrees or more. But, I’d want to install two more servos for that. We’ll see how it goes.
BTW, I worked on my throttle linkage a bit and now my radio end points are set to 135/135 for the throttle servo… max resolution and proportionally linear curve.
I soldered on the PAD to the Dean’s connector along with the servo lead:
This grommet works out to be a nice keeper for the elevator extension. I had to remove it, then squeeze it to get the Dean’s connector through. Then re-install it. After that the Dean’s connector cannot fall back through it. Sweet.
Most of my graphics showed up from P1 Hobbies (Joe Nolasco) today!
F’n Nolasco… wtf? haha
Okay, photoshoot day has arrived!
Monkey was telling Kylee, “Easy now darlin’, don’t squeeze me so tight, I’m not even sure I could fit you into the rotation”. haha
Couple of shots:
Here’s a slideshow of the shoot:
I decided (for no other reason than I wanted to try something different) to go with two 7008sb RXs. I linked them and set the second one to channels 9-14. I only have nine servos on this plane (gulp :O ) so I put each servo on its own channel and am not going to program any of the servos. :O haha I’m using three power leads into each RX though each RXs own Fromeco Badger switch. I have a SmartFly PE Comp12+ here, so after a few flights I may try that to see if I notice any difference. The BL servos are supposed to draw a lot less current, so we’ll see how it goes. Also this will be my first time on Fastest, so that’s kinda the motivation… and just to try stuff.
I have both wings and both horizontal stabs RTF with dual rates and expos, too. I soldered up one rudder servo with a PAD… and that’s all the further I’ve gotten. Still have the rudder pull/pull setup, et al
BTW, the Hitec 9380 servos travel the exact same distance off center out of the box. All 8 of them that I have. I’ve never experienced that with a servo before.
I installed the pull/pull rudder and thought the Aeroworks included hardware and setup, along with the Hitec linear travel and holding power, made the installation a breeze and very satisfying. 🙂
Okay, back to the assembly. I mentioned that everything on the plane was a perfect fit… wings, tubes, anti-rotation dowels, all bolts and blind nuts, et al. But, I did finally find one thing that I had to fix/adjust. I had put the cowl on, and I had put the hatch on, but I had never bolted them down tight together. When I tried I basically could not do it. The cowl was in the way of the hatch going on. The fix was very quick and easy. I added some 3/32 plywood pieces to the the blind nut ply pieces on the cowl. That spaced the cowl back 3/32″ and then the cowl and hatch got along just fine. Basically the cowl ring was glued on 3/32″ off of where it needed to be. Other than that the fit and finish is perfect.
I used the stock tailwheel… the tiller arm is slightly offset from the pivot point, so I put in some eye hook slightly offset from the rudder hinge line. I also kept the eye hooks the same distance apart as the holes in the tiller arm. Doing both those things allows me to go with strong springs for great ground handling because there is no tension on the non pulling spring. The one thing I did forget to do it put some locktite on the set screw of the tiller arm so it popped off (along with the tailwheel tire) on the maiden landing. Whoops. haha
Might have to go fly today:
I did! Some pics from right after the maiden (a maiden that when I went to trim out, I realized there was nothing to trim out, zero clicks):
Okay, before the maiden I realized virtually no ground clearance under the spats, and very little room around the 4″ tire was just not going to work out. So, Mickey and Jerry both showed up and dremel’d out a new hole for the axle bolt and drilled a new blind nut. I was also planning to use these DUBRO TLs, but got in a hurry to do the maiden and ran the stock 4-1/2″ tires (the Dubro’s would have had to have been drilled for the stock axles, which would have taken 5 minutes that I did not have, haha).
This didn’t leave the spat at the same angle as the tire, but as you can see in this pic I fixed that:
It was either Mickey or Jerry that fixed it (Mickey Mouse or Jerry Rig). haha But, here is how it came out:
I actually think it looks kinda cool. haha And, it is solid and totally fixes the problem with the spats. This is a 4-1/2″ tire and works out to have plenty of clearance, and a 5″ will fit but needs a slight mod to the glass and paint on the spat. Here’s the new clearance to the ground:
You’re going to need that clearance if you fly on a grass runway or ever accidentally land in the grass. Looks very good, too:
Sure is pretty, isn’t it?
Here’s a video:
The Hitec 9380s observations:
1) did you watch all the videos I’ve made about them? haha
2) I’m drawing 200mah per flight (two 3800mah RX packs, do the math, haha) I can easily get 24 flights vs 4 with the same packs on 7950s.
3) on this plane I still think I want 3 per aileron and 2 per elevator half, but we’ll see. Right now the elevator is ineffective on high rates, but that may be due to the nose heavy condition. In the video the elevator is working. I want more throw, though, and I need to go out on the servo arm past 1-1/2″ (I have 2″ arms on there) and I’m just not willing to do that on one servo… whoops, down the OCD trail here… what did you ask again? haha
Still working on the CG (I have one pound taped onto the tailwheel right now), gonna go push/pull on the rudder. BTW, that pound on the tail doesn’t even make the plane fly different weight wise. It can handle that weight easily (so cans and pipes are no problem… probably wouldn’t notice a 4cyl either); I weighed it twice and it came out between 38.5 and 39.5 pounds with a 5cell Nicad pack taped to the tailwheel. I’m calling it 39 lbs with a 3W-170 on stock mufflers (and an 8oz motor spacer, oh, and a pilot). I could get a half pound out of it pretty easy, but it flies plenty floaty as it is. Additionally, I’m working on some other refinements. But, what I can say at this point is:
* Weight is a non issue (39 lbs with a 3W-170 and pilot)
* Lands itself
* Precision rolling circles itself
* Torque rolls hands free
* Docile (trying to loosen that up a bit for freestyle, but the IMAC and sport flyers should love it)
More observations:
1) the plane, she is nose heavy, just about right for precision, but maybe even a little nose heavy for that. If you’re thinking about a DA-200 you definitely gotta go push/pull rudder and move everything back as far as possible. I might even have to do that. haha I taped a 5cell NiCad pack on the tailwheel and it barely helped. The plane is still way too nose heavy for me, right now.
2) the servos, they are nice and draw little current, but they are their rated selves. What I’m getting at is that to me I still need two on each stab and three on each aileron… for freestyle. For precision I think a guy would be just fine with one servo per elevator half and two on the wings. That is as long as he used short servo arms and setup good mechanical advantage. Just my observations and opinions, for what little they are worth. haha
3) Even nose heavy the plane hovers and torque rolls as easy as any plane. Not all planes are easy to torque roll, and most are pretty darty when they are nose heavy. This plane is one of the really easy to torque roll planes, even when really nose heavy.
Oh, and 4) slows down good for landing and the wings do not want to tip… the wing tips are very stable while hovering or harriering.
I just moved the batteries back to help with the nose heavy condition:
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