Century UK MX2

This aerobatic model from Century UK was reviewed in RCMF in 2012 and following the models progress in the RC forums it appears to be a good model for the price.  Not subscribing to RCMF I am unable to read their review so I will create one right here.  The story will go from the box to the air with as much detail as possible.

 

I have to say that I am not an aerobatic fanatic but prefer scale models and warbirds.  However, specialised aerobatic aircraft do have some flight characteristics that I like which are hard to implement in, for example a warbird.

They tend to be floaty on landing compared with warbirds which need to come in under power.  The MX2 has not changed much since it's release but there have been changes to the power system now up to Version 3 whatever that is!

I have not pictured the box on this review but I can tell you it was well packed and secure.  The bottom half of the box was made of pre-formed polystyrene and the top of beautifully printed cardboard.  The bottom was shaped to hold all the components securely and to withstand rough handling.

 

Factfile: The MX2 was originally based on the Giles G-202 aerobatic trainer, the first was a modified G-202 and initially flew in mid 2002.  There was an initial production of five which flew in May 2005. The MX2 is a carbon-fibre low wing monoplane with full length ailerons and and fixed landing gear common with aerobatic aircraft, with a tailwheel. It has an enclosed cockpit for two in tandem on reclining seats and a one piece canopy. The MX2 is powered by a 260 hp Lycoming IO-540 flat-six engine with a three-blade propeller.(There are now other options for larger engines of up to 350hp)  Optimised specifically for aerobatics and agility the MX2 can handle +12/-12 G's, allowing it exceptional tight turns and small loops and a full range of aerobatic manoueuvers.

 

Specifications: 

Wingspan 1400mm (55.8")
Length 1290mm (50.1")
Weight 1.9kg (67oz)
Servos 9g x 4
Recommended Battery 3350mAh 14.8v Li-Po

 

Inside the box was the main fuselage, cowling already fitted.  Two wings separately bagged, tail fin and stabilser also bagged.  Landing gear, bagged laid in a compartment of the box.  Three blade prop and the pointy spinner for the MX also in a compartment and bagged. A small parts bag held screws and an EPO glue tube.  Wing tube is now of carbon fibre.  (Later I was to find out that this tube is 50mm too long! )  The control surfaces are pre-hinged except for the rudder.  The cockpit area is held on to the fuselage by a locating lug forward and a magnet at the rear.  The clear pre-formed canopy is bagged separately. In another comaprtment is a bag containing the tail wheel assembly.

Unlike the Max Thrust Riot you do not get a spare prop, spanner for the prop nut.  You do get a small allen key to adjust the tail wheel horn but it is not a very good fit.  Spare three blade props are available from Century UK or your local model shop, retail price approx £5.99

The manual is just a few pages and assumes that the purchaser has built ARF's before.  I say ARF because there is a little more work to do.  Unlike the Max Thrust Riot which a beginner could assemble.  The manual does not give you a list of parts so you do need to read quickly through the manual for which screws go where and sizes (Important).  The manual images are photographs of quite low resolution so doesn't help with verfiying how to assemble.  The manual appears to be a scanned creature of a master copy.

 

 

 

 

So, lets put it together.  First job is the fit the pre-assembled landing gear.  Matching foam wheel pants are glued on for you.  The landing gear is foam covered flat wire steel with steel axle pins and the foam wheels are fitted.  The gear is secured by 4 socket head screws.  You will need to locate each leg on to the fuselage and wind the screws down evenly on each leg in turn as the foam covering makes it a tight fit.  The manual has a leaflet from the factory explaing how to get around the problem.  Don't try and fit one leg first then the other - you will struggle and possibly cause some stress or damage to the fittings. 

Second job is to fix the control horn to the elevator.  You have remove a little covering film whicxh reveals pre-drilled holes for the four screws that secure the horn and wind into the backplate.  You now have to temporarily fit the horizontal stabiliser to the fuselage using two 3mm screws and mark with a pencil it's outline ensuring that the stabiliser is square to the fuselage Take the stabiliser off and lightly sandpaper the area with the pencil lines.  Sparingly coat the two surfaces with the glue supplied and secure with the screws.

Next up is fitting the tail fin.  I did not follow the manual here by fitting the rudder at this time. I did a dry fit to make sure the fin would locate correctly.  I did not, as per the manual glue the tail fin (as this may need to be replaced if damaged in a "cartwheel", etc.  It was a very good fit with it's two locating lugs into the fuselage  and secured by two long 3mm x 60mm machine screws from the underside of the fuselage.  The fitting of the rudder requires at the same time setting up of the tail wheel and steering which is a little bit fiddly so I left it for now.  At this point I  installed my receiver (AR6200) and after binding to the TX set up the elevator whilst the rudder and gear was not in the way.

Wings have their servos installed so all that is required is to centre the servos using the radio and connect the links, snap clevises and adjust the ailerons for neutral positions.  I did this "off" model by using long servo leads and I am glad I did as you will find out later*

Inside in my model was the ESC (Top Fire 80amp 2 - 4 cell Lipo) which in it's favour has a very long power lead ending with Deans plug and the throttle lead with RF choke is extended by a short lead which is already fitted.  But the ESC was rattling around inside the fuselage!  I hated to do this but I had locate the two screws which are hidden under the cololur trim so I could pull off the cowling.  Even with the two screws removed the cowling was a tight sliding fit on the EPO fuselage.  Once removed I could unplug the ESC from the unbranded motor and weigh up how I was going to secure it.  As seen in the picture the ESC appears to be a fairly good unit.  A big heatsink included and shrinkwrapped in blue.  It could be a Black Mantis in disguise of which I have had no issues with previously.  I fitted a small Velcro patch iin the air flow tunnel which will gently hold the ESC in position.  The long power leads still had ample length in to the battery area.  I left the cowl off for now so I can check the direction of rotation of the prop.

As per my norm I pushed the wing tube in as far it would go and marked off where it entered the wing.  Pulled it out and then measured the whole length of the tube to find the centre.  It was apparent that the wing tube was 25mm too long so thats a total of 50 mm to cut off allowing for both wings.  Measuring froim the bottom side of the wing it appears that the tube goes right up to the wing servo so check your length of wing spar!

Engaging the wing spar into one wing then guiding the tube through the fuselage until the wing is nearly engaged into the recess in the fuselage.  Feed the servo lead through a dedicated hole into the fuselage and then gently push the wing into th e recess.  Note:  This is a very good tight fit!  Taking the other wing, pushed it onto the wing tube and slide also into place ensuring the servo lead is not trapped.  *At this point, judging by the tight fit I hazard a guess that this model will have to be transported with wings attached. See below Two 3mm x 50mm machine screws secure the wings from inside the fuselage.

 

 

 

 

 The rudder has three plastic pivot hinges pre-installed, two of whcih locate into the tail fin and the lower one into the fuselage.  The tail fin has pre-drilled holes for the hinges but on my model there was not one for the lower one into the fuselage. Not a big issue!

The rudder has recesses for the tail wheel horn bracket and control horns. See image.  They are secured using small screws.  I hope this idea stands up to time in use.  I dry fitted the rudder to see where the lower hinge will locate and punched a small hole in the fuselage in readiness.  After verifying the alignment I applied some glue to the holes and fitted the rudder.

Supplied were two 45mm Z links whcih connect the rudder horns to the tail wheel swing-link.  With the tail wheel bracket in position I found that the links were far too long to connect.  37mm was more like it!  Should I attempt to rebend the links?  not havinga z-bend tool I favoured making a mod to the tail wheel bracket.  (If this had been a larger model I would've replace links with adjustable ones).  Modifying the tailwheel bracket entailed drilling a new hole for the rear most screw and a clamp to hold down the front end of the bracket.  Not ideal but a work around for now.  In retrospect I would say to Max Thrust put slotted holes in tail wheel bracket to allow for adjustment.  If the links are not exactly the same length then the wheel will not centre in relation to rudder.

The cockpit floor is a good fit into the fuselage.  Located by a large lug into the front andheld down by a magnet at the rear.  On the underside is ply plate with a servo arm screwed to it.  This is used apparently, in conjunction with an elastic band pre-fiited in the fuselage.  On locating the cockipit you should hook the band around the servo arm which gives you a form of back-up if the magnet fails to hold down the canopy in tight turns. 

The clear bubble canopy has guide lines molded into it and all that is required is for you to cut along these lines or where necessary so it fits the cockpit section perfectly.  I left a very tiny amount of overhang at the front to cover the gap betweenthe cockpit and fuselage giving a more integrated appearance.  If you decide to instal an idiot, sorry I meant a pilot now is the time to do this before glueing the canopy with the supplied substance to the cockpit section.

Moving to the front again I temporarily fitted the spinner backplate and 3 blade prop.  This is secured by a flat washer and 10mm nut.  I had previously set up the control surfaces and servos with a NiMH pack so all I needed to do now was plug in a 4 cell 3000maH LiPo.  I pushed the throttle to max and plugged in.  After the first bleep pulled the throttle down to low and waited for bleep followed by 4 bleeps (4 cell recognised) and a final bleep. (Armed)  Carefully opening the throttle a little found the prop was rotating in the wrong direction. a quick swap of two of the motor wires and voila!  With the model secured checke dthe high and low throttle positions.  No problems here.

Remove the prop and plastic spinner backplate and refitted the cowl.  I have to say here that it is an extremely good fit and you do need to push it back on exactly or the two machine screws will not pick up again with their original positions.  With the colw refitted now just requires fitting the spinner backplate, prop and spinner.  The spinner is secured using a long 3mm machine screw from the centre of the spinner into a threaded hole in the motor shaft.  The spinner, prop and backplate are a close fit.  Will maiden it with the supplied prop but may swap out for a Irvine spinner and two blade APC-E if efficiency is less than ideal.

Inside the fuselage tunnel is a sticker saying "Battery Here".  I placed my 4 cell here with the power lead end of the battery in line with end of the tunnel over the said sticker.  Checked CG and found the model was very slightly nose down.  Perfect for maiden then!

Unfortunately at time of writing the weather has descended into continuous rain and or wind so a maiden and video are unavailable at present but his article will be updated as soon as.

Note:  Ensure you fit the correct length of machine screws into their positions.  50mm for wings, 45mm for stabiliser, 60mm for tail fin.  Don't ask how I know!

My Impressions

  •  For it's price a very good value model.  As of date of publishing was £139.99 from Channel Four Models.
  • Very well packed and secured
  • Generally most parts fitted exactly - tail wheel bracket let it down.
  • Three bright colours.  Green favourite so I went for Orange.  Have not found anyone with a Yellow one.
  • Ideal model to throw into back of car for a quick session of fun (Subject to wing mods as below)
  • Excellent spare parts availabilty.  You could make a multi-coloured model up if you so wished!
  • Not quite true Plug N Play.  User with some experience of ARF's would be okay.
  • There have been reports of the ESC  failing but his may be on the earlier power versions
  • Not for beginners - Recommend the Max Thrust Riot - See Relevant Article.

 

 

 Wings Tight Fitting: I was not happy about the tight fitting of the wings and also the carbon tube.  Assembled the model would be struggle to fit in anything except a large estate/hatchback car.  It wouldn't fit into my Astra Van!  So carefully pulling the wings off again I sanded off the paint on both wings and also the fusleage sockets which now give a more desireable sliding fit, only going tight on the very last mm or so.

Footnote: Replacing the stock three blade prop with an APC-E two blade an inch more in diameter did not give much difference in performance but the current draw and wattage indicated lower demand by the two blader by some 65 watts.

  Evaluation