Kyosho Caliber 700 Review
Written by Mark Christy Wednesday, 02 December 2009 23:28
Caliber 700Introduction
Kyosho burst on to the helicopter scene with the "plastic fantastic" Concept 30 in the early 90's. Until this point Hirobo had this section of the market to itself with its Shuttle range. Despite the Concept suffering reliability problems from some poor design choices, or lack of testing, it was a sales success.
The Concept was designed by World Champion Shegitada Taya of Kalt Space Baron and Thunder Tiger Raptor fame.
The Concept line was expanded over the years to a include 60 size model and many other variations. However with Taya out of contract and the need to revitalise the line of models against more modern opposition Kyosho decided to "go it alone" and launched the Nexus.
The Nexus was a disaster for Kyosho and saw their market share plummet. From being the club pilots favourite brand they vanished from flying fields almost over night.
To be fair to the Nexus it wasn't as bad as some people made out. However it was not an improvement over the Concept and there were much more modern competition about now. Kyosho went quiet for a long time and it was widely expected they would pull out of making Helicopters all together.
During this low point for Kyosho the chief designer at Hirobo, Makato Kunii, was looking for a new challenge and to start from a clean sheet. He presented Kyosho with the revolutionary design for the Caliber 60. A ladder frame chassis, belt multi stage transmission and a push pull tail rotor control were just a few of the notable designs.
Kyosho put the model to market with a very high price. It's aim was to be the finest model helicopter ever produced and to be sold in limited quantities. The design was a moderate success. Despite not winning Kyosho the coveted World Championship it was now seen what Kyosho could make if they put their heart and mind into it.
Following the Caliber 60 was a 50 and a 90 size model. These were all carbon/metal models with equally high prices. More recently Kyosho have turned the solid Caliber foundations into a range of inexpensive plastic 30 to 50 size models. The model under review here is the Caliber 700 which is an electric powered version of the 30 size model. Time to put it through it's paces and see if it is good enough to erase memories of the Nexus.
Obtaining a Caliber
Kyosho models are distributed in the UK but not supported by all hobby shops. Midland Helicopters had stock of the 700 so an order was subsequently placed. Spares are also plentiful and available from the same source so I have no concerns about breaking it! Whilst wider support would be good it is a chicken and egg situation.. shops will not support the model until it becomes more popular.. people will not buy the model until it is better stocked in their favourite hobby shop.
Opening the box
The Caliber comes is a bright colourful box which is covered in detailed pictures and figures about the model. It also has a carry handle.
Upon opening, the top section is taken up with the boom, canopy, decals and instruction manual. Removing these reveals a cardboard tray which protects the numerous bags underneath.
Each bag is numbered and contains related items for a specified build stage. These numbers are shown in the manual at the appropriate points.
The manual is well laid out and is in Japanese and English. The quality of the diagrams are excellent an help contribute to an easy to follow manual. Each stage shows the required parts along with the size of screw(s). Important information is clearly flagged at appropriate points. An exploded diagrams list at the back completes the booklet. The manual is available online here
Building - Chassis
We have a full build video to complement this written review.
First stage to the build is the frames and transmission. The frames are modelled on the larger 60 model and are quite detailed in their design. Having to support several vertical shafts for the multi stage transmission also equals more bearings than normal. The bearings are cheap unbranded items but this is to be expected. The servo tray is a one piece moulding and has lots of space for all kinds of boxes. Canopy mounting are unusual in that the Caliber employs a kind of "popper" rivet system. This does away with the dreaded rubber grommets and actually provides a very good canopy locating system. The mounts are not symmetrical front to back and you have to make sure you get them the right way round. All of this is held together with a bunch of self tappers. Again this isn't ideal but is to be expected at the budget end of the market.
When installing the mainshaft and drive shaft special care has to be paid to the pinion and the mainshaft collar. This collar is a split collar design; which is in fact much more preferable to the standard grub screw versions we normally get. However it sits underneath the top bearing inside the frames. Access to the pinch bolt is through a hole in the frames. If you get the collar the wrong way round however you can't get at the bolt.. check and check again before you assemble! The pinion grub screw locates in a recess in the drive shaft. For this to happen the shaft has to be pulled up so that the tail belt take off is in line with the boom.
The undercarriage is a large one piece item. It is quite flexible and does "what it says on the tin". My only reservation is that it is held on by self tappers. These I feel will strip fairly early and will need replacing with proper nuts and bolts. Having said that vibration should be low being electric and they may last longer than I give them credit for.
The quality of all the components were first rate. The frames a particularly impressive set of injection moulding. There were no burrs or tidying of any kind required on them and everything fitted perfectly.
Building - Motor & ESC
The Caliber comes complete with a specially designed motor and ESC. These items are contained within a large metal housing. This makes for a very neat assembly into the chassis with just a handful of bolts. The Caliber is also available as a pure kit with G10 plates allowing you to mount your own motor and speed controller.
The motor assembly features two sets of wires exiting the bottom. One set are for the main battery, the other set connect to a small "CPU" fan that sits on the heat sink at the front of the model. Whether this is really needed is a moot point but it is a nice touch and it will be interesting to see how well the supplied motor/esc combo works.
Building - Rotor head
The rotor head and swashplate come mostly pre assembled so the first thing I did was take it all apart and check it was built correctly. In my case it was and loctite had been used in good proportion. However I would still check yours.
The rotor head is an underslung flybar arrangement with a metal centre block. The mainshaft is 10mm and the flybar 3mm. The paddles are weighted items with removable caps allowing you to adjust the weight to your preference. The head is fully ball raced and was a nice slop free item fully assembled.
The blade grips feature metal reinforcing plates all the way round with 4mm bolts to hold the blades on.
The mixer arms are unusual in that they reside on the flybar itself. The arrangement is actually very similar to the Hirobo Evo range of machines except here the arm runs at 90 degrees to the flybar rather than in line with it. This makes the flybar seesaw a simpler design but provides stranger link angles. Its a proven system though and the whole assembly is nice and free. The mixer arms themselves feature two positions. One for higher flybar input (F3C) and the other for higher swashplate input (3D).
The washout base itself is a simple plastic block with no kind of bronze bushing in the centre. Whilst it moves freely enough it wasn't a completely slop free item. This is one of the few places I can see being beneficial of a metal upgrade. The guide ring however is adjustable and will allow advancement and retardation of the swashplate timing. This is a good feature as it allows the model to be trimmed mechanically perfectly before adjustment of the transmitter.
At this point I would like to commend Kyosho on their ball joints. The threaded rods were good quality but the plastic links themselves were just perfect. They snapped on to the balls with a very reassuring click but once on were incredibly smooth. No sizing was needed on any link and they have all been the same. A pleasure to build!
Building - Tailrotor
The tail rotor gearbox is made of two halves with a straight forward pulley assembly for the belt. The hub is large and features two radial bearings and no thrust races. The tail blades are thing flexible plastic items which will be fine for beginners and sport flyers but will need changing for more advanced flying.
The pitch change mechanism is fully ball raced and features a novel under and over system. The upper mechanism is attached to the lower mechanism by a vertical shaft that runs in ball races. The bottom arm features a T-Piece that runs push-pull rods down to the servo.
Again, like the rotor head, the finished system is very smooth and positive. All the plastic parts were of a very good quality.
Building - Setup
For this model the following components were used:
Cyclic servos : Futaba BLS252
Tail rotor servo : Futaba BLS254
Receiver : Futaba 8 Channel FASST 2.4ghz
Gyro : Curtis Youngblood Enterprises Mini G
Regulator : Castle Creations 10amp Mini Regulator
Blades : NHP 550mm
The Caliber front radio tray has lots of holes and mounting points for radio. Finding a home for your electronic boxes is a breeze.
The instruction manual provides link lengths for all but the servo links. Whilst this was initially frustrating to me I also realised that no manual to date has produced correct link lengths because of the huge variance in servo dimensions. Therefore this omission can be accepted as no matter what length they put in it would probably have been wrong for my servos anyway!
The manual does not provide suggested transmitter settings either but does provide suggested pitch and throttle curves for the model. Again whilst this does not provide a starting point for the transmitter it does at least get the builder to think about the setup a little more and learn how the machine works. I personally feel this is a good thing as it allows the builder to learn about his model and how the transmitter operate the controls rather than just relying on what the manual tells you to do. People tend to remember things much better when they have to do them rather than just reading about them.
With everything installed I levelled the swashplate off and used the excellent 12FG transmitter swashplate software to make sure it was level through out its travels. The BLS252 servos were very well matched and needed very little tweaking in the transmitter.
With the stock link lengths and transmitter set to 60/60/60 on the CCPM swashplate mixing I had zero degrees at mid stick, -11 at the bottom and +14 at the top. Cyclic travel was 5.5 degrees.
The mixer arm arrangement ensures there will always be a bias towards positive pitch. This I personally feel is a good thing as you can setup a good symmetrical curve for 3D in the knowledge you will always have a little extra for the throttle hold and autorotations.
Stock settings gives 25 degrees of pitch range and no binding or danger of the washout pins dropping out of the radius block. It should be easy to get near 30 degrees without too much tweaking.
The Mini G was setup with stock settings and will tested in conjunction with the kit plastic tail blades. A set of Radix carbon tail blades are on hand if the blades prove to be too flexible.
Build Summary
A very painless build indeed. Everything fitted as it should, the parts were of a good quality (exceptional in some cases) and the manual was clear and easy to follow. I would have liked to have seen allen bolts and nuts in some areas but on the whole I have very little to be concerned about. The model has a high plastic count but features metal where it is needed (swashplate and rotor head). I can now only hope the model flies as well as it builds.
Flight Testing
Since the build the Caliber has sat on my shelf as the British weather has done its upmost best to transform our flying site into a boating lake. During this time I came into possession of some Turnigy 3000mah 30/40C 3S battery packs. As these were some what lighter than the 5000mah 6S packs I was intending to use I went ahead and fitted the G10 plates Kyosho provide for battery mounting. Along with these I made up a Y harness to allow the 2 packs to be connected in series.
One fine Friday afternoon the sun finally shone and it was off to the flying field for a quick, and bitterly cold, first flight!
The ESC has a very soft start and it is recommended that minimum throttle is not reached whilst you are flying as the spool up time will be quite long. Therefore it's best to set up a flight mode for hovering RPM at all stick positions rather than relying on your normal flight mode curve.
The Caliber rose up in to a steady hover with the tracking perfect. A couple clicks of trim were required on the cyclic and the throttle RPM raised a little to remove a slight nod. Once this was done the model sat eerily stably. The belt transmission also aided a very smooth and quiet set of mechanics. A couple of pirouettes and gentle figure of 8's were performed to see how the model tracked. The Caliber was steady and neutral in all orientations and really inspired confidence. There were no trim changes in the wind and the design pedigree certainly was showing.
After a couple minutes hovering the model was put into the aerobatic flight mode and a 90% throttle curve (At this point I am not using the governor setting on the ESC). The model has a good positive rate of climb. I would rate it alongside a good 50 size nitro model and well ahead of the 30 size nitro models it represents in size. I have no doubt it could cope with the lengthened blades and boom of a 50.
After doing a few fast passes the model was put round a loop. This was large and graceful and no issue for the Caliber. A number of rolls were performed and the model tracked perfectly axially around the boom. If only all models flew this well on the first flight!
The cyclic response was good but certainly not enough for some hard 3D. Remember at this point all the weights were in the paddles so there is plenty of scope for livening things up some more.
The tail had a good positive feel to it and the plastic blades were certainly adequate. As this was a first flight nothing too taxing was placed on them but they did the job that was required. Certainly the Radix will probably be needed once we start getting more adventurous with the flying.
With light fading and the cold stopping the hands from working the Caliber was brought into land and the warmth of a car sought!
Back home the 3000mah packs took 2400mah on charge, which is just right for the 80% Lipo rule. This was from a 5 minute flight mixed with hovering and aerobatics with a few full power climb outs.
Conclusion
Kyosho have certainly produced a lovely little model here. The quality of the components are first rate as well as the kit being competitively priced. The Caliber was vice free in handling and inspires confidence in the pilot that it will do exactly as asked. It's a shame this size of model is not more in vogue as I feel this is all that is counting against it. Having said that it shouldn't take much to scale it up to a 50 size which I'm confident the motor and ESC are more than capable of handling.
If you fancy something a bit different to the usual crowd then I can firmly recommend the little Caliber. An easy build with plenty of adjustments available should make it easy to tune for any pilots flying preference. It certainly restores Kyosho's reputation as a manufacturer of dependable and appealing model helicopters.
( 11 Votes )
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