스크랩 자료 프레데터X10 집중탐구~~

[곰바우(박훈식RCDJ)]

	The first thing I noticed was how heavy the chassis is, it's 194g, not sure how this compares to similar moulded chassis like the xxx4., I am not sure of the material used, its stiff but quite heavy and very solid feeling. Unlike most moulded chassis this is almost half the car, with the lower gearboxes and pivot blocks all moulded in. The quality looks good, with some post-mould milling and drilling which seemed to be quite well done. The cell slots are beveled and despite a couple of rough edges seemed good.

The main shaft is next, this is a solid carbon fibre rod which needs the slipper assembly and front one-way adaptor epoxying on either end. This is a job that I was unable to perform as mine had already been epoxied. Its a shame that this isn't something that is done in the factory as Its quite a critical job and some people might well not be able to do it.

The spur can ofcourse still be removed from the shaft and is harder than most shaft driven cars because both gear boxes need to be taken apart and the spur slid off the front of the shaft over the front one-way adaptor.

The slipper assembly consists of a machined slipper clutch coupling with a slipper plate incorporated. The 73t machined delrin spur gear is placed on top and another pressure plate is next, there are no inserts or friction pads, this is purely anodised metal pad against the machined delrin surface. The tooth profile on the spur gear is a bit odd when compared to another spur like that from the rc10b4, It looks almost like there are more teeth than the diameter of the spur would normally llow.

3 Large spring washers provide the tension to clamp the spur and are held by a simple alloy nut. Its a simple slipper design. TTech suggest the adjustment range between low and high grip tracks is 1 turn, so very fine adjustments are needed.

One major issue with earlier predators was the gears in the gearbox, they were notoriously weak, this seems to have been addressed well. The gears are a total re design and the pinions are now a very beefy looking steel which should'nt have any issues! the crown gears are a composite plastic and look very beefy also.

Onto the Differentials, both ends of the car use differentials, at this time there is no front one-way option. The diffs are similar looking to others, but like the slipper clutch very simple, there is no locking nut or spring of any kind like you find on a similar looking tc3 diff. The diff halves are machined from Hardened anodised alloy and the diff plates are keyed with a flat to prevent slippage. Ceramic Diff and Thrust balls are provided, which is a nice touch. The diff screw clamps it all together (with a touch of threadlock). Both front and rear diffs are identical. The lightweight outdrives and ceramic balls add up to a very light diff at only 10g.

Front and rear diff out drives sit inside alloy sleeves which then sit into the gear boxes. You need to shim the gears properly at this point using the provided shims, there are suggestions in the manual for setting this up but its best to check for yourself. The bearings on the out drives were quite well packed with grease so I soaked them in motor spray and gave them a light oiling, probably not really necessary on a drivetrain like this but hey. Mesh front and rear on the beefy gears was excellent, Ttech advise a small amount of play in the mesh, similar to that of a motor pinion / spur gear, with the supplied shims and following the instructions this is exactly what I got, I cant see too many problems arising from the gearboxes on the new predator.

The Centre shaft one way is a unique design that has a the ability to limit the one-way effect and add front braking in the form of a plastic sleeve which is glued to the one way assembly and sits over the alloy one-way sleeve on the front of the carbon prop shaft. 3 O-Rings are then placed on the carbon shaft and these can be slid over onto the plastic sleeve one at a time to provide progressively more friction on the prop shaft, which basically adds some front braking effect, It is described as a subtle adjustment by TTech.

The gearbox tops are sealed with the chassis by running a bead of silicone diff grease all around the mated surfaces, this is a bit of a messy way of doing it but ensures no dirt can enter this way. There is no “interlocking” of the 2 halves of the gear boxes, but there doesn't seem much chance of the tops going on skewed and messing up the mesh, still, it doesn't feel quite right just sitting on top like this. This is where you get your first real taste of the titanium hex screws on the x10, they look very similar to the Ti screw kit I recently reviewed for the Kyosho ZX-5. They are moulded instead of the more shiny Lunsford machines Ti screws. There is a slight play between the 2mm driver and the screw, make sure you have a decent quality driver and take your time and you will be ok.

The front gearbox is screwed together by 2 Ti screws and a long steel screw, most likely because Ttech couldn't source an appropriate Titanium version.

Screwed together, the was now a definite tight spot when spinning the spur gear, I relaxed all 7 front and rear gearbox screws a quarter turn and the mesh was much better with no tight areas, very free.

The front gearbox top has some holes which appear like they were drilled after the moulding, just like the main chassis has, these don't look overly pleasing to the eye with material proud of the hole they look a little messy. I already knew my front gearbox top was incorrectly drilled, because the rockers which transfer the suspension movement to the inboard shocks, collided half way though their travel. (Left: middle photo). I sent the offending part back to TTech for a replacement, and manage to borrow a new gearbox top from a fellow racer and predator expert, Graham North. This was much better, the front rockers now had a good mm or more gap. The pins that the rockers sit on (top right) were both "finger pressure" all the way in, these holes are very loose, I tightened as much as i dared. (more in the test race about this) The screws clamping the gearbox together were not so easy to put through this gearbox top, you couldn't attach and screw them in one at a time as they wouldn't then line up and the other screws were impossible to insert. I had to put all 3 screws in with the gearbox top hovering above the chassis, then and only then could I screw them down. The holes just seemed out of line with each other very slightly. Seemed fine when screwed t

The rear large shock mount is next, and requires the anti roll bar and wing mounts screwing on before being fitted to the car, the carbon is thick at 3mm and with the low profile should be very strong. There was a problem on my car here, the rear gearbox top has a lug which helps locate the rear shock tower, it basically pokes out into a corresponding slot in the carbon tower. Basically the holes and lug on the tower were slightly differently spaced to the screws holes and slot on the tower. The difference was only around half a mm, but it meant I either put the screws in first and crushed the lug, or located the tower first on the lug and then wasn't able to screw it down as the holes didn't line up. I filed the lugs and the inside face of the slot on the tower, this enabled the tower to finally sit flat like its meant to.

Although I mentioned the lack of lugs to locate the gearbox halves together, lugs are only good if they are in the correct place. The wing mounts look odd compared to everything else on the car, they look cheap as a first impression, the clear plastic doesn't seem to belong to the rest of the car, they are fairly flexible though and seem like the could take some abuse.

Shock tower wouldn't sit flat.

Rear tower and transparent wing mounts.

The rear suspension is of a “double wishbone” type, not the usual lower wishbone and upper camber rod, camber can be adjusted to a small extent via the hub, it has a elongated hole which the upper arm slides within, clamping down a screw and nut secures the camber change. The wishbones use hinge pins inboard and ball joints at the hub, the lower arms have an adjustable rod which connects the hub and wishbone to provide adjustable toe-in. This is fine if you have the ability / tools to set up the toe in, but likely would confuse some people and lead to some un-equal toe settings. The top wishbones need to have a shock mount secured to the top by 2 screws, here the manual also suggests running a small bead of thin CA glue around the mount to stop it moving. I cant quite see why this cant just be moulded as part of the upper arm, it would surely make it more accurate, lighter and with 2 Titanium screws, also cheaper. The top hingepin is quite thin and runs between two alloy bushes which sit inside the opposing carbon towers. the wire is held into the alloy bushes with a grub screw.

The grub screws are the last to be tightened after its all put together. Its also best for the grub screws to be level (with each other) otherwise the hingepin can sit at a different angle inside the bushes and bind the suspension. The lower rear wishbones are supported by one intricately bent hinge pin which goes through the rear shock tower and the chassis acts as the hinge pin block, supporting the pin behind and in the centre of the wishbone. The left side lower arm wouldn't fall under its own weight, I took it apart again and the holes in the arm where the hinge pin goes were slightly out, the angle on one side wasn't a direct line to the other side, I ran the hinge pin through a few times, same with the chassis, and upon reassembly everything was fine. The lower arms hold the hubs, one side with a rigid ball joint and the other side with an adjustable rod which enabled unlimited adjustment of rear toe settings. The large ball joints on the lower wishbones are quite stiff and the smaller ones on the toe-adjusters are quite loose and are quite easy to pop off with very little force, I'm not sure if this is a problem when racing the car but to stop them coming off completely I made sure all the open sides faced outwards (so it can only fall inwards).

Drive shafts on all four corners are the same overall length but the front has shorter axels and longer shafts and vice versa, and are quite a simple design. A 2 piece “drive shaft cap” is glued together over the end of the dog-bone and acts as a slider on the outdrives, protecting them. The business end consists of only 3 parts, the main shaft, the axel, and a pin. The pin simply goes through the axel and shaft and the drive shaft is able to pivot on the pin in all directions. The pin is then held in place by the bearing in the hub, which covers it at both sides, very simple and neat.

Plastic sliders, glued in place. Business end of shaft is safe from dirt.

You begin to realise by this point how brief in areas the manual is, some parts you are guided through, like the top wishbones, others like the drive shafts or lower wishbones you are given a exploded view of the parts and that's it.

Sometimes you are reading one part of the manual for the next step, and suddenly you realise half the car (ok, not quite) has been finished without any mention in the manual !!!!

Front suspension is similar to the rear, first job is to set some short pivot pins into the top gearbox moulding to support the top wishbones, these need pressing really well into the gearbox top otherwise the suspension will bind. Unfortunately its a similar story to other post-mould drilling as one side seems centred and the other side is off centre by half a mm or so, its not a lot and it most likely wont affect the handling at all, but these sort of things don't feel quite right. Corresponding pins bolt through the front carbon fibre pivot pin plate and secure the upper wishbones front and back. Lower wishbones mount up similar to the back, with a long pin going through the wishbones and lower chassis holding it all together.

Pressing the suspension pin into the gearbox.	Front upper arms	Front arms mounted

The rockers mount up next, these mount onto pivot shafts that are screwed into the gearbox top, as I said earlier, this is a replacement gearbox top as the holes were misaligned and caused the rockers to actually hit each other. Push rods link the lower wishbones to the rockers, these screw into holes which are drilled into the wishbones after moulding and again seem to be somewhat random in their positioning although I cant see it affecting performance.

Front uprights do the job of the steering knuckle also, instead of separate items like on most 4wd cars, and pivot on large ball joints at the end of upper and lower arms. These ball joints are TIGHT and definitely add a lot of resistance to the movement, both steering and suspension action are affected. I was told to "pinch" the cups with some pliars, which streches the plastic and frees things up, it seemed to work slightly.

The motor mount clamp screws onto the chassis and is braced against the rear carbon shock mount.  The mouting disc then screws onto a motor and slots into the clamp. One screw at the side clamps it all together, I was advised to ditch the kit screw and use one with a larger 2.5mm head so I can get more torque on the clamp, so I used one from the kyosho zx5 kit, its slightly longer than the kit Ti screw included so has even more bite in the mount. My motor clamp has a bevel on the edge that meets the motor plate, some clamps don’t have this bevel and I believe its now been revised to have a sharper corner which would dig in to the motor disc better to prevent slippage.

The steering is the regular twin bell crank design supported by 4 flanged ball races, which press into the front gearbox top, make sure the bearings sit flat here as one of mine did not and required a very small amount of material taking off the gearbox with a scalpel, otherwise the steering would bind quite badly. The link between bell cranks is supplied in the form of a thin carbon link, the link sort of floats, resting on the chassis with a delrin bushing screwed in at each end which prodrudes into the bell cranks. The very long link to the servo is a thick bent wire which looks like it belongs on an R/C Airplane.The bell crank end uses a springy fastener which is bent open and closed over a hole on the bell crank, once on it feels secure but some people use either a zip tie or heat shrink to keep it together.

The long link protrudes through a hole in the chassis and no matter what I did I could not get it to stop rubbing on the chassis. I ended up widening the hole slightly to stop any interference. Once all together, the steering actually feels really solid with very little slop.

The carbon link is a known weak spot and already TTech have an upgrade out in the form of a steel version. In all fairness no one could seriously look at that carbon link and think it would last very long. The car on the left is owned by Richard Isherwood of Professional Racing. You can see the heatshrink over the link to the servo also.

The shocks front and rear are identical and utilize short hard anodised alloy bodies, dual rate springs (rear only), rebound valves (front only), foam volume compensators and titanium nitride coated shafts.  Only one O ring per shock is used to cut down on sticktion.  The shocks are not threaded for height adjustment / preload but use clip on plastic spacers. The O-rings supplied in the kit were, frankly, no good. I got the car new and already the shocks were leaking.   The O rings appear to be made from a hard rubber rather than silicone, despite only having one per shock they are far from stiction free. I purchased a set of Racers Edge metric silicone O rings and rebuilt the shocks with these.  They are not quite as free (loose) but are much more “buttery smooth” and shouldn’t leak quite as easily fingers crossed. TTech already offer upgrades to the kit Orings which I would guess are similar to the racers edge ones I used, mine came 10 to a pack, Ttech only supply 4 in a pack. Springs front and rear are quite soft and the car can bottom out with a drop of only a few inches, this is something TTech are adressing with new springs coming soon.

The spacer that goes between the O ring and the C-clip is vital to get the right way round, it took me a while to see in my dimly lit cellar that there was one side more open than the other, its very hard to see honest!
The Ti Nitride shock shafts are a nice gold colour like all the similar shafts on other makes of cars and those from MIP.  While all those others are highly polished, the shafts in the X10 appear slightly dull and with a hint of texture when you run a fingernail down them, I’m not sure if this is important, part of the design or just a dodgy batch, with the racers edge seals there was no hint of leaking and they were smooth feeling so I guess its ok.

The front shocks use a flat flexible disk under the piston, which Ttech describe as a “rebound valve”, the general idea of this seems to be to allow the shocks to react quicker to hits on compression but on rebound the disc would then block the hole in the piston slowing the return slightly.  Some people seem to be either taking this off or using it on the other way around, at the top of the piston, slowing the compression and speeding up the rebound, either way its another tuning option. Filling and bleeding the shocks is quite a nice experience, you simply fill the body with oil, screw on the bottom with piston etc, loosen off a turn and slowly push the piston all the way in, nipping the bottom tight when the piston is all the way in.  This took all the air out and the shocks were very smooth and air free.

The wheels are a white dished design unique to TTech, they have 4 lugs which mesh with the drive adaptors, referred to by TTech as "X-Drive".  Speaking to Tom Yardy (TTech team driver) the wheels are unfortunately not compatible with Acetone (to remove old tyres), they will melt.  It is also apparent the wheels are more brittle than similar wheels from others.  They are at least cheaper than most other makers wheels and are also available in bulk. Wheels mount up perfectly true and wobble-free on the large adaptors unlike most other manufactrers wheels.

COMPARISON PHOTOS

Front All cars only have cells in, though the predator tends to sit lower than the other two when fully loaded. Not much i can say about these comparisons as the cars are so different. Generally the preds diffs look higher placed, but the overall lower CoG is very evident. Inner camber link is a lot lower and longer on the xx4.
Front Zx5 shocks sit even higher than the xx4, and ofcourse much-much higher than the X10. Camber link is similar height but further inboard.
Rear apart from the diffs, the suspension is looking fairly similar.
Rear Rear diff height is fairly similar here, inner camber link is a lot higher.

The shell and wings are the icing on the cake as it were.  Previous predators were tested in wind tunnels and the like, its not clear if this new "aero" package (as TTech describe the shell and wings) got the same treatment, but its low and pretty  sleek. The car looks fantastic, but that is partly the design of the car rather than the body shell its self, personally speaking I quite like it. The shell covers the car quite well, the sides interlock with the chassis stopping any ingress of dirt though painting an intricate design along the side would be quite difficult.  The front of the shell goes over the front laydown shocks, I found the shocks did take a little paint off here.

There isn't much room for electrics in the X10, most people place the ESC on top of the servo. The Keyence I use here with the heatsink is placed just far enough into the centre to poke up into the "drivers" cockpit. Fitting a brushless in here would be hard work.

TEST RACE

For the test I used a KO Propo 2343 Fet servo, Orion core 10x5 with V2 end bell, Peak 3300 Cells.

For the test of the car, I went to a club meeting outdoors (yes, in december), at Bury Metro Buggy Club. The track is a multi surface affair, mainly astro turf, quite a bumpy and demanding track and a good test of the X10.

I had hoped for nice weather but it was raining all the way to the track, having been up until 5am that morning building the car I was not going to be put off by a bit of rain.

I ran my Kyosho for the first 2 heats until I had the X10 ready to race.

In my first outing with the X10 I was quite timid for the first couple of laps then started pushing it, I was very surprised at how well it went around the bumpy undulating Bury track, it really was very quick indeed. On lap 6 whilst going round the banked corner the car seemed to keep going straight and ended up off the track in a heap.

I thought it was over for the day after only 6 laps, having heard a lot about the weak carbon steering link I assumed it had given out. When i inspected the car I realised in my haste to get it done I had missed off the threadlock on the balljoints which link the bellcranks to the steering knuckles. The screw had worked loose and fallen off. Ah well.

In those 5 Laps I did manage to go 3/4 of a second faster on my fastest lap, compared with the Kyosho ZX5, the car did have better tyres on and more grip, but I was also driving it slower because I did not want to break it so wasnt taking as many chances. Its hard to say if given the same tyres it would faster or slower, but it is quick and handled the bumps very well.

Light was fading and it was time for the finals with only 6 racing laps under the belt of the X10 and lying in 3rd place from the zx5's qualifying time. I was behind 2 xx4's. Off the line the predator proved its explosive acceleration and I was straight into 2nd, after 2 more corners I was in first for a brief moment when I clipped pole man John Price's xx4.

 From then on I simply could not get round the track without spinning out randomly, I ended up a very poor 5th and couldn't really understand how things had gone so badly in the final, as the car seemed so good earlier.

Looking at the car in my hand it was very obvious, the left hand rocker assembly was in no way attached to the car, it had pulled clean out of the front gearbox on that first lap, in effect the car had been scraping along the ground for almost the entire 5 minutes.

After the final. Left hand rocker hanging off, it still finished though.

It took 18 days for TTech to reply to my email asking If I could exchange my faulty gearbox top, They were however friendly and helpfull, and the gearbox top they sent in exchange was spot on in all regards. Im told phoning is best with TTech.

After the brief race day the car needed a good cleanup so I took the oportunity to check things. The chassis cells slots are sharp and act like a shaver, shaving a nice buildup of dirt into the car, but hey, it was terrible conditions so its fair enough. Front wheel was very badly cracked all the way through, I didn't notice this until cleaning after the racing, could have been due to the very cold weather but still not good. Shocks front and rear seemed to fair very well, there wasnt the usual filth all over the body and shaft since they arent in the spray of the tyres. Pins in the driveshaft joints on all 4 corners were visibly worn, mainly from the looks of it by the sharp edges of the dogbones, it wasnt possible to remove the pins without tools. I am told the pins are meant to wear and be replaced instead of the other more expensive parts wearing. Aparently. Gears in both gearboxes were in good order. It was obvious the steel pinions had thrown off a lot of tiny metal particles, which with the grease TTech advise you put on all the gears makes for a nice grinding paste, its advisable to strip the car after the first 1-2 races and clean it up, after that the gears should be worn in, I would guess they just aren't cleaned up properly at the factory.

Rear shocks still nice and clean.	front wheel smashed.	front drive pin, immovable!

Conclusion

I think the X10 is an awesome looking car, no one can dispute that. Despite the general design being around for many years its still very unique and impressive.

I was personally unsure about the car until I drove it, The car is great on the track, It's quick and handles, to my surprise, very well indeed even over the bumpy Bury Metro track. Its not quite the same feeling as a "normal" buggy, and it looks like it shouldn't work quite as well as it does with the minimal ground clearance and constant scraping of the chassis along the floor.  When it was first released the predator was ground breaking and ahead of its time, others have caught up now but I think its fair to say the x10 is far from being left behind in performance terms.

I could not bring myself to recommend this car to everyone, Its a lovely car in some ways, the design and the way it drives are unique, the list of components is fantastic with its carbon, titanium, alloy and ceramic parts, and of course it looks amazing. The car seems to be let down however by the little details, the inconsistent quality, the poorly drilled holes, the choice of materials in some areas, the fit of some parts and the rushed manual. This car could be so much better.

I know TTech have been working hard to resolve some of the Issues the car has, with new parts appearing all the time, but it seems they will have a way to go to make the car as user friendly as other cars in its class. If TTech can bring the quality up to the levels the car truly deserves it would be an even better car for the masses, for now I think you have to be enthusiastic about it to overlook its niggles and stick with it to make it work for you, this is a pure racing car after all. It would be all too easy to bash the car for its numerous little faults, but on the track it performs.

My "verdict" ?.... Serious racers only need apply, for now.

Under heavy landings from jumps etc, its apparent that the spur gear can strip no matter how you set up the slipper, I've seen this first hand a few times myself. It seems that because the main shaft is supported by only 1 bearing on either end, that during a landing, if the chassis twists the spur can actually move slightly away from the motor and strip the teeth off. Most shaft drives have a centre bearing where the motor mount is, the x10 does not. One fix to the problem was shown to me by Peter Moss of Professional Racing, basically peter has added an extra bearing to his team cars right next to the rear bearing.

Spur movement with chassis flex.

bearing

The extra bearing has 2 effects, firstly it reduces the movement of the shaft at the spur end, and reduces the spurs movement away from the motor in the event of a hard landing. Secondly, TTech have recently introduced an upgrade in the form of alloy rings which sit around the gearbox pinions to stop them breaking under certain conditions. The bearing takes care of this job also as it sits in the same place, its also stronger as its steel.

.Extra bearing added to the shaft.

[곰바우(박훈식RCDJ)]

요건 김창균님 참고하세요~~~!

[c2kim-김창균]

넵 감사 합니다. 온로드 사진 자료실에 "배워니" 로 글쓴이 검색하시면 반정도 번역된 글이 있습니다. ^^ 맨아래의 베어링 팁은 베어링 싸이즈가 잘 없더군요. 전 다른 방식으로 했구요. 프런트 쇽 고정부위의 샤시보강 팁이 있는데..조만간 올리겠습니다.

[시니]

늘 좋은 정보 감사드립니다..^^

[정서방]

이놈 가격이 어느정도해요??

[배워니]

약90만원이요...

[난다리XG]

참으루 좋은차량이에요..저두 한대 굴리는중인데......