NOTE: click on any pictures you want to see in closer detail
There are several Wot4 kit's available in hobby stores, the build from plan type, ARTF type (glow), ARTF XL size (wingspan of nearly 1.8metres!), and also the kit I bought the WOT Mk2 Foam-E (A-CF020) - maybe there are also more?? all of these kits are based on the successful design of british designer Chris Foss.
This was also a good chance to get my son's building skills started in what promised to be a 'cleverly designed model that can be ready in 30 minutes'. We prepared a few tools for screwing, measuring etc and cleared a big workspace to get started....
First step was to take the pieces out of the big box and take a bit of a looksy
It all looked promising so we took a hunt through the manual (always a good idea to read completely front to back before starting - shame we didn't though woops)
We did check to see that we had all the parts though...
So the first part of the build was to fit the tail plane both horizontal and vertical pieces. They're right when they say this is a clever design as it seems to be all held together with one bolt. It all slots together tightly and looks convincing although I do wonder if it will loosen up with some flying? I'm not a big fan of a single bolt as if it shears (or the mount sheers) then you loose the lot. I may yet go back over this lot with some foam glue, we'll see...
Apologies for the quality of the pictures here, the foam is so bright white that my camera was having trouble finding something to focus on. I would also like to add that it's an advantage to have a spare set of hands here as you have to juggle a few different angles and bits to poke in here and there. Still take a deep breath (and maybe a cup of tea) if you're getting frustrated and sure enough in a minute or to it will all be together.
The elevator servo (pre installed) needs to have the control rod threaded through at this stage. This can be a little tricky and for first timers I would recommend gently guiding it with a set of needle nose pliers while you have an accomplice slide the tail assmebly forward. Another option is to take out the screw from the servo horn which makes it a lot easier to thread the narrow gauge rod through the screw clamp.
Once the tail is pushed in to place there's a second keep screw that holds the steering bracket to the tail
If you have trouble getting this fiddly screw in place it maybe worth just starting it on the first thread before assembling the tail like so:
The next part of the build was to fit the undercarriage. This is a nice springy piece ready assembled with the wheels in place and sufficient spring to (hopefully) deal with grass landings without ripping out the underside. One tip here is to support the back of the model so that the tail is not resting on your work surface. The tail is not strong enough to take the weight you need to put down to screw in the undercarriage and you don't want to be cracking out the glue even before you make it to the flying field!
Although there are pilot holes drilled, the plastic that you are screwing in to here can be a little tight, so if you're having difficulty then put the undercarriage aside for a minute and thread through the screws so that the holes will play ball once the undercarriage is back in place.
With the undercarriage fitted, the instructions then call for the receiver to be fitted. In this case we're going to be reusing a hitech 35mhz (huh oldtech? ) 4 channel rx that was once fitted to my twinjet(s), and as the cables and all are ready to go in the model I elected to skip that step and leave it until last in order to do the tranny setup at the same time.
So then it was a case of fitting the propellor to the front end. The Wot4 comes with a prefitted outrunner brushless and really they couldn't have made this any easier. The prop assembly is pre assembled in the kit and it's just a matter of removing the two screws:
Taking the prop adaptor and driver:
Pushing it home on the engine shaft
Slipping on the propellor and then just doing up the retaining nut with a prop spanner or any spanner really
Then after reassembling the spinner and slipping on the main wing, that is it mechanically speaking - THE PLANE IS BUILT!
On the box they claim 30 minutes to assemble. Because we fiddled around a little with the hardware, taking photos (and video) it took slighly longer. However if I was making a second one I would say that 5 minutes would be enough. However....
Filled with confidence we decided to move on to the decals/stickers. The foam is very white (as you can see in the pictures), however the fueslage does look quite bare and the foam surface does look a little pitted close up, so the stickers really add quite a lot (aesthetically speaking) and so I figured it was worth our while and trying to get it right.
In order to do so though it was necessary to take a short coffee break and play spot the sticker. The manual just basically says 'apply the stickers':
This is easier said than done. While the stickers look great, and they obviously make the finished plane look great, if you don't have a lot of experience here it can be a little confusing (and daunting). Not to be detered we started with the windshield as it looked to be the easiest one to identify. This proved successful as we found that there was a faint outline of where the three stickers pieces should be fitted.
The next logical place seemed to be the underbelly decal which is in a very attractive blue scheme.
however it was necessary to do some trimming for the battery door and also to remove the undercarriage (no mention of this in the instructions?)
Also we made some cutouts at the front end so that the decal could sit under the nosecone in order to avoid having it stripped back with prop wash when in the air
We then moved on to the side pieces which added a lot to the model, however these are tricky enough to apply. There's some complex curves there to work around so take your time. We were not able to get it done without some foldes in the sticker, however maybe if you're an old hand with solarfilm (or something similar) you could do a better job..
Towards the back of the model there are some diagonal stripes and these were a real kicker. In the pictures on the box and instruction manual it clearly shows two strips that are diagonal on the side and flat across the top. Well I must need origami lessons as there was no way I could pull that off. Using some clever cutting with the scissors we managed to get one stripe and then despondently moved on. Probably it is possible and lots of people will say 'blah blah its's eay' etc, however just a note for the manufacturers here it would be nice for a little bit of extra guidance on this point as the lines really set the model off in the pictures.
Because the model is a high winger, the next part was paramount to get right - the wing stickers!
Knowing this I cleared everything off the table, made some room on my bubblewrap (so as to protect the wing) and laid it out parallel and easy to work on. The stickers have a little 'kick' at one end which mean that basically it's the piece that overlays the top and bottom section to give a continuous colour with no visible join. I found because of this it would be easier to put the bottom stickers on first and then put the kick on the top.
The bottom part went easy enough and lulled me in to a false sense of security. No sooner had I peeled the top sticker did it bend around on itself and make a sticky mess. I managed to prise it apart but at the cost of a few creases as before, this is a stage that would be useful to have a spare set of hands to help out.
I then also found that because you have to rotate the wing a bit to get the sticker lined up on the edge it becomes a bit of a juggling match - if those stickers even breath on the bubble wrap they stick fast and hard.... aargh, more creases and cursing and finally I had the sticker ready to put down. For whatever reason (call it Murphy's law), I couldn't get the sticker to sit straight without bubbling/creasing I landed up pulling out an old pitch gauge to use as a straight edge and working the sticker on to the wing that way. This resulted in an 'OK' effort, but really this is almost a skill that you need to practice to get as good a result as what comes is shown on the box. Probably some people just toss the stickers on there and fly, but I wanted to try for a good result..
Another point to take in to account is that the stickers go over the control surfaces, so I'd recommend getting a razor or hobby blade to relieve these a bit so as not to create any restriction on the aileron movement. I used scissors, however that was a mistake as I lightly grazed some of the foam hinge underneath - luckily not too badly!
And at the end of that, it's then possible to put on the main wing and admire your work!
Looking very nice, the challenge will be keeping it so nice!
Cracked on a bit with the WOT4 again last night. There were still a couple of stickers we had left to apply, program my transmitter and set the control throws. I was also curious to disect it a bit and see if I could find out what spec the pre installed hardware is.
We started by removing the prop, spinner, and nose cone in order to take a close look at the brushless motor. I'm a bit of a newbie on brushless technology but I was hoping to see a part number or sticker that would inform me what KV the motor was rated at.
Well all I could figure out is that it's an outrunner, and also that it looks very nice. Despite having no indicative stickers, numbers, stamps etc, I could see that it has a highly polished outer casing and looks like it's made to a reasonable quality standard. As we know you can't judge a book by it's cover so we'll see how it performs over time.
Moving further back in the model I took a look at the ESC. It is also suitably 'vanilla' looking. The cables look like they can handle a decent current, the BEC and throttle cable are mixed here. There doesn't seem to be any programmability (no surprises there) however a welcome addition would be a power switch, as often fiddling about with a model to try and unplug deans connectors is not as convenient as having a small switch. The battery compartment has just enough room to fit my 2250mah 3s lipo and the speed controllor, maybe you could squish a bigger pack in there if you were happy having the cables hang out of the bottom of the battery compartment while flying - that woudl look a bit naff though if you ask me!
We then undid two screws to remove the elevator server and see what it is. From the top of the plan it just looks like a little black box. And guess what when you take the servo out and there's no stickers or markings, it just looks like a tiny black box!
In order to give a better idea of size (afterall I could be a Hagred with huge fingers!) I put it down next to an Align digital DS410 (metal geared type) and an old Multiplex MS-X3 (still sporting a touch of a KIA twinjet). Way back when I thought the Multiplex servo was micro and small. But these newer generation ones make it seem just normal, or maybe a touch on the big size!
So basically we're none the wiser on what this power kit is. Anyone know??
Moving right along we put the front end back together and took on the final stickers.
I had a sheet of TEIN stickers to hand and figured that it would personalise the Wot4 a bit so that it's not just identical to all the other Wot4's out there. So with a MR Tein on the front and a shock on each side, now it's a talking point.
The next one was the big Chris Foss Ripmax Wot4 Foam E sticker across the top of the wing. I questioned if this was just needless advertising but my son thought it looked good so he put it on and I think it does add a bit to the model. The tail plane also got the same treatment.
At this point we hooked up a battery and the little hitec receiver I am using and went about setting the throws. As it turns out in my transmitter (Futaba Field Force 9) the throttle setting is reversed. Thankfully we had a strong grip on the plane as when the ESC armed it lurched forward with a huge tug, giving a startle but also inspiring confidence that it shouldn't need much of a runway to take off. We then made a video of the pull out of the engine and also the satisfying ziiiiinng noise the outrunner makes.
Anway, the control throws were set fairly well for what was shown in the manual - rudder spot on, Elevator 2mm extra throw, airlerons 5mm extra throw but rather than dial these back with end point adjustment, I programmed in 50% exponential in order to make the flying experience calm and collective at mid stick and 'super fun' at the other end
During this setup I did notice one thing though that was not quite right, the two elevator halves are just out by a millimeter or two.
(note left down, right up)
This is not that uncommon on ARTF's I guess and while it could be trimmed with the airlerons easy enough it could make the plane scroll out of loops, knife edge and rolls. The halves are stuck hard on the connecting rod so the only real solution to this would be to run a hacksaw through it to seperate the halves and then install two tail servos in the back with a Y lead. It can be done alright but in the end this is a cheapy foam ARTF for a bit of fun in the park and not a pattern ship. I'll see how it flies and take it from there, it could have worse habits yet, or maybe I'll be so out of practice I'll deck it on the first flight and not have to worry about it.
Let's hope not as the plane is looking pretty nice at the moment....
Just as a follow up to this, I've had a few flights on the Wot4 now and it doesn't dissapoint. The minor difference in the elevator halfes don't seem to be a problem, the plane will fly straight and true and can even handle quite a bit of breeze.
Here's some photos of normal, inverted and even knife edge flight.
(Thanks to JayC for flying the Wot4 while I took these pics)
I found the standard motor to be quite perky on a 3cell 2250mah lipo and the Wot4 will easilly pull a vertical climb from coasting horizontally.
Very nice plane at the price and fully recommend for beginners, casual fliers, those returning to the hobby, or even advanced pilots who want an old reliable to fling around in the air for a bit of fun!
Re:Wot4 FoamE MK2 ARTF build thread 2 Years, 7 Months ago
Well Wot 4.2 turned up and I spent some time over the past two days building it. This one resembles the first but with some quality issues
Firstly the nose cone has the blue paint applied, but no white! thankfully the plastic is kind of an off white colour so from a distance you can't tell but it sure doesn't look as good as the first one.
Secondly, the tail wheel was broken off from the fueslage.
Thirdly the vertical tail fin securing nut was stripped.
Fourthly the hinge lines are soooo wafer thin that I will have to apply hinge tape.
Fifthly the motor does not zing as nicely as the first one and sounds a bit like it has a bad bearing or something.
I see that the ESC has been changed for a Hobbywing 40amp unit, although I'm not sure if this was changed by www.arrowmodels.com or Ripmax, as the previous Wot's ESC was a gold colour.
Overall it seems like this model is an earlier version of the MK2 as it seems to have a lot of the problems that are described in rcgroups.com or modelflying.co.uk
So uh, hopefully the servos will not fail on me like they have for other people... Anyway I'm getting it flight ready, it just has to fly as a trainer and I'll be having my fun with the ST Blaze (which is made at the same factory )