RC 4x4 models (EN)
WLtoys A949 unboxing
2016-02-22: WLtoys Vortex-A949 unboxing
It's been some time since we acquired our last RC "cruise missile", aka the WLtoys Vortex model A979 . After a few upgrades it made it successfully off-road for more than 10 minutes (actually 2.5 hours was good enough :) ).
Today, we got a very similar RC toy from GearBest - the WLtoys Vortex model A949 rally cross car. It is almost the same platform as the A979 , so I'll skip some of the usual description and will concentrate only on the differences. You can always look at my A979 unboxing review here .
The bodywork is made of durable Lexan and it shall represent a rally (or rally cross) car. These cars are produced in two variants as shown on the package box. Both variants differ only in the bodywork:
- A949 version A - this blue car of mine. Even though it looks quite realistic, I'm not sure, which of the real rally cars was this one made after. A Citroën?
- A949 version B - red one, certainly looking like a Ford Fiesta R5.
Interestingly, the vendor states, it is a scale of 1:18 as all other vehicles from the WLtoys Vortex A9x9 series. The model is 14cm wide and considering the fact, that a real rally car can be ca. 180-190cm wide, the real scale would be 1:13 or 1:14 in this case. That looks very interesting for a specific intent I had in mind for a while ;) .
The body needs to be taken off to get to the battery, chassis and other components. The body is held by four clips, which were very rigid at least on my A949 . So before shooting the unboxing video, I "opened" them just a little to make it look better on the final video. Normally, when you get your A949 , please be careful when taking off these clips as noted at the A979 .
Again, you do not need to take off the body at every opportunity. With just a little bit of skill you can get to the master switch, as well as to the charging connector of the battery without removing the body at all.
Warning: as I've confirmed at the A979 - the electric motor can get very hot when driving (namely driving flat-out :) ). Even though there is an aluminum heat sink, the driver must be careful about motor's temperature and stop after 15-30 minutes of driving (that's normally the endurance of the stock battery).
The chassis has independent wheels suspension with coil springs. The A949 chassis only has different axle arms, wheels and front and rear area under the bumpers. Front springs were too soft at least on my A949 . The car sometimes didn't even want to lift itself into idle position. I had to disassemble the front suspension and stretch the coil springs a bit. Now it's perfect (considering the fact, that there is also enough space to mount holders for a heavy NiMH 5Ah battery pack again :) ).
The car is equipped with hydraulic oil dampers. There is really oil inside and it is visibly leaking on my A949 when the suspension hits its upper limit. The A979 specimen was better in this regard, there was just a thin oil film on two of the dampers (or may be there was no more oil in them :) ).
There is an interesting difference - at the A979 I was complaining about flexing and bending during springing action. The A949 has much better axle geometry - the arms seem to be much better stabilized when springing. We'll see how that influences driving experience, the A979 has been very "nervous" underway. I hope the A949 would behave much more consistently.
The connecting shaft between the axles is plastic and there is no center differential. All half-axles are made of metal shafts as well as the joints in the wheels. There is a visible amount of looseness in wheels' bearings - surprisingly not axial, but horizontal! Both axles have an open differential.
Front axle. Under the front bumper there is a massive block of spongy foam which is to absorb potential frontal crash forces.
The rear axle's design is quite unusual. In fact, it is a steering axle stabilized with two rods. It looks like the vendor took maximum of existing parts and only made the axle non-steering.
The tyres are made of very soft rubber with a simple "gravel" pattern. I hope the tyres won't stick that much to the ground, I'd like to do some attractive drifting.
The car has a relatively large turning radius - which is good for fast driving, but bad for tight rally-like corners. Interestingly, the left turning radius is a bit shorter than the right one. The servo behaves well and smoothly. Steering suffers from the same manufacturing inaccuracies as at the A979 . There is a considerable amount of looseness both in steering (virtually all of the joints) and in suspension, all can be clearly seen in the video. Moreover, there are significant eccentricities of rotating parts e.g. joint axle drive shafts.
An interesting question is "waterproof-ness". On the GearBest's web site (and also on the package box), I saw a note that the car IS waterproof. Even though I mounted skirts around the A979's chassis to prevent water getting into the electronics, it might actually be true - all the electronics is covered with some king of semitransparent resin, so actually water should do no harm. The same applies to the A979 .
The battery is a 7.4V Li-Po with a capacity of 1.1Ah. It is equipped with a BEC connector - the same as at the A979 . So now I have two stock batteries :) and even compatible 3D prints for mounting my big NiMH battery.
What kind of terrain is the vehicle intended for?
The manual says that the car manages to drive well on hard surfaces, sand and grass land. This is even more important than at the A979 . The A949 is a rally car, do not expect any rock crawling possibilities.
Anyway, I moved all four suspension components to the inner position. That was an easy operation and gave me a few more millimeters of ground clearance.
And finally, here is the unboxing video. It is pretty much the same as at the A979 .
However, I strongly recommend watching it till the very end. Then you'll surely understand, why I was carefully checking the car's total width before obtaining. And there is much more to come regarding this idea ;) . Stay tuned!
2016-03-03: NiMH battery pack upgrade
As already noted, I've 3D printed my NiMH battery pack holders and mounted them on my WLtoys Vortex model A949 . Suprisingly, there is exactly the same amount of space above the front axle as on the A979 , so I really didn't need to change the 3D model for the holders.
I hardened the front and rear springs (dismounted and stretched by hand :) ) and mounted the lower shocks's joints into their spare positions closer to car's center.
That has helped me to gain some extra millimeters of road clearance (because I'll be driving primarily off-road) and also keep the car above the ground with the heavy battery. I can change car's setup to on-road configuration again moving the joint to their original positions.
After a few short test runs the car is much more stable when driving. Of course, that's the effect of huge mass added to the chassis. Also, it is much less agile when cornering (more sliding!), so the drive looks more realistic. Stay tuned for first outdoor rally cross tests and video :) !