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Building the Raptor 50 Titan
For a year or so I’d had the use of a loaned Raptor 50 to play with and it was a lot of fun. Having a little 50 to muck around with is great, you don’t have to think with a 50 like you do a 90, you just play. I gave that little Rappy a good pummeling trying all sorts of craziness which would often result in the Rappy on it’s side on the ground after a good bounce off the ground. It was a good honest little Rappy and when I gave it back to it’s owner I thought that I’d have to get something to replace it, eventually. Until then I’d play with the Vigor and the Sylphides. I didn’t do anything about replacing the Rappy for about six months until my mate Andrew got a Raptor (along with everyone else) and I was the odd one out. The Vigor is great to fly, but there’s nothing like a little 50 to throw about. I needed to get a new Raptor. Having got rid of the Synergy I had all the radio gear left over from that so all I needed was the kit and an OS 50 so I went and leaned on the local dealer and walked out with a new Raptor 50 Titan, OS 50 and SAB Carbon Blades. TITAN 50
Apart from that, it’s just a standard old Raptor, which is exactly what I wanted. Why didn’t I go for the SE? Well I already have a metal head block for the Raptor 50 and in my opinion, that’s really the only upgrade that’s needed. The purpose of a 50 is for cheap fun that I’m not afraid of crashing because of the cost. The setup for this helicopter would be:
So with all of that, it should be a fun little setup! THE BOX The big ‘milk jug’ canopy took up the majority of the space and everything else appeared just as Raptors do, very simply. ASSEMBLY Next is the main gear and autorotation hub assembly which is very easy to assemble apart from the circlips that go on the autorotation sleeve. I lubricated the one way bearing with Tri-Flow lubricant and went to work putting the circlips on. After ten minutes of getting no where I jumped in the car and went and purchased circlip pliers and we were done. Circlip pliers are a worthwhile purchase. The plastic washout arms are straight forward, once again circlips are used to secure the pins. Perhaps one part that might be worth while upgrading in the future is the washout and washout arms. The plastic was just a little too flexible for my liking, but I won’t upgrade those till I bust these. MAIN FRAME ASSEMBLY SERVO TRAY Once in, you slide the servo tray ends over the ends of the elevator cradle. I really like the way the Raptor servo tray works, it’s so very simple, yet very effective. Bearings are used to support the tray at it’s central rocking point where the push-pull elevator linkage is mounted. The push-pull linkage is a great addition which eases the load on the elevator servo and as such, makes the ‘feel’ of the elevator servo more responsive. ENGINE INSTALLATION There wasn’t – it was just terribly balanced. I ended up removing A LOT of weight from the ‘heavy’ side of the fan, so much so that I was getting to the point of not knowing what to do next if I hadn’t removed enough, perhaps I should start adding weight to the ‘light’ side? Unfortunately there wasn’t a moulded location to glue the GV-1 magnet in on the ‘light’ side, so I had to pick the best of the bad situation. In the end I go the fan to balance within reasonable tolerances, if this was my F3C machine I would probably have thrown the fan away and got a new one and tried again, but this is good enough for a 3D machine. Normally, once balanced, I would dial gauge the fan on the crank shaft but because Raptor fan hubs are threaded, there’s really not many options, so I was at a loss there. It would have to do. This little exercise just bought home the point these things need to be checked prior to assembly and if I had this much trouble getting things to be even close to right, how would a novice to the hobby get on? If you’re having trouble with vibrations in your Raptor, it could be a good idea to check your fan balance, cause mine was shit. With the clutch installed I installed the engine into the frames which was a very straight forward exercise which makes a pleasant change from the JR machines I have which REQUIRE scientific accuracy in the engine placement to ensure that everything is happy. Following the engine installation is the skids, nothing unusual to report there. ROTORHEAD Assembling the head was very straight forward, I greased the thrust bearings and installed the harder red dampeners. One thing I really like about Raptors is that the flybars have small slots in them where the flybar arms screw into. This is great. No mucking about with measurement or anything, it just works. I used loctite to secure all the bearings in each part of the head to ensure minimal slop which I achieved. I also made sure to use a ball link reamer on each ball link on the head to ensure that while the links were a tight fit, that they were smooth and did not ‘stick’ which is crucial. I did not get too specific with the rod lengths as I will cover this in the subsequent ‘setup’ article. TAIL BOX The tail pitch slider assembly is also very straight forward and very free of slop. The gear box itself is well supported by bearings at each end and has a large pulley for the belt in the middle with an idler pulley at the top. Once all bolted together it’s all nice and free with no slop. Very easy. The boom is great. At one end there are two holes, at the other there are two slots, you can’t get them mixed up, the tail box goes on the end with the holes (there are mouldings that fit in the holes) and the other end slides into slots. You can’t get it wrong. Feeding the tail belt down the boom can be a pain, but I generally attach one end of the belt to a long stick and push it through. The belt then slides around the tail drive gear below the main gear. The one thing I did change from standard is the use of a JR Venture 50 boom clamp which means that I don’t have to run a horizontal fin (which I try not to do on my 3D machines). Once the boom is fitted with the boom supports the whole tail structure is very solid which is great to see. The tail push rod slides easily through the three pushrod guides which with the tail mounted servo should provide a smooth flowing tail linkage. FITTING THE COLLECTIVE SERVO This is all done putting the intermediate bell crank linkage in the servo bay where the tail servo would normally be on ‘classic’ Raptors. Thunder Tiger provide an impressive plastic mount that is very reinforced which I very much doubt will flex under loads. I’m always keen on installing the ball link on the servo tray in the hole closest to the main shaft which meant that the collective bell crank would be installed in the hole nearest the front of the helicopter. This would yield the best pitch response. The pitch servo is mounted using two standoff blocks to push the servo out from the frames and make the linkages straight up and down. I’ll cover the setup of the collective linkage in the subsequent setup article. FITTING THE AILERON AND ELEVATOR SERVO The elevator servo is also mounted on standoff blocks to push it out from the frames. I’ll cover the setup of the aileron and elevator linkage in the subsequent setup article. INSTALLING THE TAIL SERVO I’ve mounted the tail servo so that the tail pushrod is under the middle of the boom at all times to try and prevent the pushrod deviating from the line that it naturally wants to take which makes for a freer flowing action. INSTALLING THE GV-1 SENSOR INSTALLING THE RADIO GEAR I’m not great with wiring these things tidily however I ended up routing all the servo leads in one common path which at least gave me some control over where everything was going. I used one Velcro receiver wrap to contain the governor and gyro headunits as well as the receiver then fastened it all to the radio tray with double sided tape and electrical insulation tape. I tend to use insulation tape because you can get a good grip on everything and it tends not to let go like some Velcro can if not administered properly. It doesn’t look great, but it works great! CANOPY & STICKERS I made a bit of a mess of the stickers too, once again due to my lack of skill, but I was able to save a little dignity in the end by cutting the bubbles that appeared in the stickers later... MACHINE SETUP FLYING THE RAPTOR Happy with how things were going, I turned on the governor and the engine slowed down a little. At first I was suspicious that the governor wasn't holding the headspeed at the correct speed (1650) because it sounded quieter than I expected, however a quick check with a tachometer confirmed that indeed everything was correct. I hovered the little Rappy around for a tank then landed to make sure nothing had come loose. Nothing had. The next flight it was time for some gentle aerobatics. I'm not one for spending tank after tank just hovering round 'running in' an engine, I believe in 'start as you mean to go on' by which I mean fly it normally, but don't load the engine up and gradually lean the engine out until it's operatoring optimally. Into Idle Up One and the engine started singing at 2000RPM and I began doing some circuits. The heli flew nice and straight with the white paddles. I then did some rolls and noticed a slower roll rate than I wanted and also the machine wasn't rolling straight which I was expecting. I leaned the engine out a few clicks as well. I went back to the pits and got an extra 20% ATV out of the elevator and aileron controls to see about getting the roll rate up. Second flight the roll rate was better, but still not what I was after, so the lighter paddles (red or green) would be required. I then started adjusting the phasing ring to get the roll straighter (I'll cover this in a future article), after the second adjustment the little Rappy was rolling better than the Vigor! The dampeners didn't seem that good though. The red dampeners I had in it I had used in the old Raptor and were now seeming to be more flogged out than I expected as the machine was shaking during tic-tocs. I've ordered some CarbonExtreme Dampeners to try so that should be interesting. I also noticed that the tail would sometimes washout during some maneuvers, so I replaced the stock tail blades with some Carbontech 95mm blades which immediately fixed the problem. Ah, it was great to fly a little Raptor again, at our field we have a flight station that is pretty congested with a fence, some trees right in front of you, some more to the right of you and you stand on a mound. With a 90 you have to think a lot to keep it out of trouble (ie the trees or the fence), with a little 50 you don't care, you just chuck it around and it's A LOT OF FUN! Later in the day it was time for some push over autos and the SAB blades are just great at this, they spool up so well after the push over, you can skim the head button through the grass, do a big quarter loop then fly in backwards, lots of fun! That night I put some green paddles and brand new red dampeners in. The roll rate was much better and the heli was still not pitchy (my main priority - I CAN'T STAND pitchy helicopters!) so we'll stick with those paddles. One thing I did do was shorten the long pitch links between the swashplate and the pitch arms by one turn to move some pitch off positive and onto negative to give a more even feel. I can't tell you how impressed I am with the OS 50 Hyper and Hatori 522 Combo, it's perfect! I just can't get enough pitch out of the little Raptor to even come close to loading it by doing climbouts. You can ofcourse load it if you make a screw up with cyclic and collective, but other than that, it's a little power house, and ever so smooth! SUMMARY What about all those flash metal heads Si? Don't you want one of those? But what about the 4 million different types of setups you can offer with delta, flybar ratio, etc? Surely Si, with your F3C background, you'd want to play with all that? But I need to buy some upgrades to make me feel good about my Raptor, what should I buy?
Once you have bought all of the above, buy the following:
You don't need all those flash metal bits! Spend the money on productive stuff! So the little Rappy is now inducted into the fleet and joins the old trusty Vigor, the two Sylphides and the damn T-Rex (which is somewhere - still busted). You'll see more of the little Rappy in upcoming articles where I test out some new hardware on it.
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