Day 1

I bought this kit of a friend, who bought it when it came out, but never got around building it (he´s a collector more than a modeller, but then again, aren’t we all?). When I got home, weary after a modelling contest (Modell Göteborg 2011) and a week of frantic kit building before that, I thought I´d be able to let this one sit for a while.. but I was wrong.

The gigantic box is filled to the brim with other boxes, containing varous goodies, like the tracks, the electronics, photo etch and other “this is why this kit is so darned expensive” parts. Underneath the boxes are plenty of sprues. As you can see, there are a few.

This will be a large beastie when it´s done

The finished gearbox. There are two electric motors, but only one of them is actually powering the tank. The other is used for turning the tank. As far as I figured out, when the tank is driving straight ahead, only the propulsive motor is running, when turning, the turning motor will rotate in either direction, depending on which way you want to go. When the propulsion motor is stopped and only the turning motor rotates, then the tank turns on its own axis. (Corresponding to the “Wendung” gear shift position on the real tank )

Did I say the gearbox was finished? Why is this one left out? I´ve gone over the instructions a few times, and I have turned the driveshafts by hand, and it seems to work as it should. Maybe this gear is used later on, for turret traverse or something?

The two final drives.

Test fitted the “power pack”, the final drives and the drive sprockets.

Each of the dampened suspension arm stops are made from five parts, and they are working, due to a tiny spring inside the cylinder.

That was all I had time for the first evening. I will have to get my self a 4 channel radio transmitter and a few cans of NATO green (Tamiya Modelling Magazine used seven spray cans on their Leopard according to their review!) to be able to finish this project. I plan to use the TS-range cans for the lower hull at least, since it is made of ABS and since it will take the most beating. Other parts I might be using alclad primer and the tamiya acrylic colours instead.

Day 2

I spent the lunch break searching for a suitable transmitter. I would like to have a 4 channel digital 2.4 GHz transmitter so that I do not need to worry about frequencies. Unfortunately two out of three places in Gothenburg that I know carry this kind of equipment did not have what I needed. The third place is closed on mondays, so I will have to try there tomorrow if I can. I am pretty sure on which transmitter I want. I´ve read about people using a 4 channel Futaba 4YF transmitter. At the two places I looked they wanted to sell me a 5 channel Spectrum transmitter, but since it has digital trim switches, instead of the old analogue kind I am not sure it is going to work with the Tamiya electronics. The trim is used to fire the weapons and control the light on the tank.

Since both hobby stores that I know carry the Tamiya TS-range of spray can paints (and the XF acrylic range as well) have decided that mondays are modellers holy day of rest, and therefore are closed, I have not been able of getting my hands on the needed spray cans.

So, without a transmitter to test the electronics with, and without the needed paint pretty much all there was to do was basic modelling. On the other hand, there is a lot of parts that needs assembling, and since it´s a tank, much can be built before painting. However, I very much would like to get the suspension and the wheels in place, but I have decided that it is better to paint the underside of the hull, and the wheels separately first.

So what did I accomplish this evening? I started off by making the support rollers and gluing them in place. I also glued the buffers I made yesterday in place.

Next up was detailing the hull On the engine deck there are the air intakes for the engine, and the round inlets for cooling air. These are to be detailed using photo etched grilles. Tamiya has solved this in a nice, beginner-friendly way. The etched band around the air intakes is locked in place in a simple but effective manner.

The net on the radiator intakes has tabs that goes in to slots on the part, the tabs are then folded to lock the net down to the plastic part. Unfortunately this does not work as well as it should. the net feels quite lose. I will probably add some glue to glue it down later.

It´s not this bad, I have not yet put all the tabs in their slots yet.

This is the underside of the radiator intake. Note the tabs sticking out of their slots. The metal part in the center is there to enable magnets on the hull to keep these parts in place. They are removable to enable access to a pair of screws that hold the upper hull to the lower.

Seen as a plastic kit, this kit is quite uncomplicated. The fit is in most places perfect. There are exceptions however.

This is the ony place I have found so far, that will require a touch of putty. This is the join between the upper hull and the rear radiator outlet grille.

The feeling I have is that it is an upscaled version of the Tamiya Leopart 2A6 in 1/35. There are some more details, but not much. Compared to some other static offerings in this scale, from other manufacturers, this kit is quite basic. What I think should have been included in a kit of this scale and most of all, this price tag, is a PE-fret with proper tool clamps. The tools and tool clamps on this kit are pretty much exactly as they are on the 1/35 sibling. It scarcely work in 1/35, and I believe it will look bare in 1/16. I probably will either order an after market set, or add some scratchbuilt details later. Another strange and annoying omission is the loaders machine gun. It´is simply not included. No mount, no gun, just the skate ring around the hatch. I wonder why Tamiya left that one out? Maybe they didn´t have time to design the sprue? Maybe they thought that they would have to make it “working” like the coax gun, with light and sound? There is however an after market solution available, I might go that route later.

I had to do some mechanical work also, I decided, so I built the ball bearing that holds the turret. The bearing is built up with two rings using ten ball each. When I was done, adding the small, fiddly balls I found that Tamiya included two spare balls. Nice that I didn´t need them I thougt. The very next thing I did was dropping one of the rings on the floor, spreading the ten tiny balls all over the living room. I found all but one, so now I have one spare left. I hope they are not supposed to be used somewhere else.

The ball bearing is screwed to the turret, but not yet screwed to the hull.

When rotating the turret I noticed that the front is touching the air intakes. I hope this will change when the hull is reinforced by the sound box. If not, I will have to remove the intakes and grind them down a bit. I have heard more worrying things regarding the engine deck and the turret overhang to the rear, but so far there is plenty of space. However, the heavy electronics module is placed to the very rear of the turret, so it will probably bend down some.

A while ago noticed that one of the local hobby stores in Gothenburg (Hobbex) had a sale on model kits. In a pile of kits with a 50% rebate on them I found two boxes of the Tamiya 1/16 bundeswehr tanker. I bought both sets since my plan was to have one commander, and maybe one loader also. However, when I opened the box for the first time yesterday, I found that Tamiya had been nice enough to include TWO figures in each kit. A complete figure AND a leg-less figure for use in the turret. Maybe I can make one figure as a driver also. If the fit is good on the Leopard, it is less than stellar on the figure.

A bit of a size difference. It´s easy to say that 1/16 is about twice as large as 1/35, but one tend to forget that the bulk is quadrupled.

I really should finish that Strv 122 some day.

Unless I find some paint and a radio tomorrow there is still plenty of basic assembly left.

Day 3

Today I spent a fortune on Tamiya paint at one of our local hobby stores. This particular store used to sell RC kits and equipment, so I had my hopes up of finding a suitable transmitter as well, but as I said, it USED to sell RC equipment. Unfortunately for me, they had stopped doing that. So I ordered a transmitter off the interwebs insted. I did leave the store with all the TS-61 NATO green spray bottles I could find. They had four, and I bought them all, the were not cheap. Almost 90 SEK, which is about € 9, or close to $ 13.

Needless to say, it was paint-time later on. I sprayed all the road wheels, idler wheels and suspension arms while they were still mounted on the sprues. The attachment points on the road wheels will be hidden underneath a rubber ring. The idler however does not come with a rubber “tire”, but needs to have its “rubber” painted on. It seems strange that Tamiya designs the road wheels with rubber parts, but not the idler. My guess is that the strain on the idler is too much for a simple slip on rubber ring to handle, it might come lose or deform too easily, while on the other hand, rubber on the road wheels is needed to make the running smoother and more quiet. that, or they are just cutting corners regarding production cost.

I also took care of the only visible seam line I´ve encountered so far.

I puttied the small seam on the side, and used stretched sprue to fill the gap on the top. I then massacred the stretched sprue with liquid plastic glue and a hobby knife to make it look like the weld seam that real Leopard 2s got here.

There are some ugly seams on the lower front that needs to be dealt with. Unfortunately the result of my puttying and sanding above turned up being not enough, so I will have to return to this part later.

I also glued the bore evacuator to the gun barrel. The Tamiya kit is extremely well enginered towards simplicity and as idiot proof as any kit can be, but nature always invent a better idiot, the saying goes. This new and improved idiot is me. I managed to put the evacuator on upside down. I noticed this when I was about to put the muzzle on, the MRS gadget on the muzzle was pointing the wrong way, to the left, instead of right. I managed to pry the evacuator off, re setting it at its proper position.

The evacuator has the glass fibre texture of the real thing.

There is a small seam line to take care of, on the evacuator. I am probably to blame for this, since I had to pry the parts apart after they had started to bond, when I put the part upside down.

When most of the paint had dried I progressed with the torsion bar suspension. Each assembly consists of three brass bearings, one individually numbered axle, one torsion bar, a plastic plug and a screw. The black plastic axles are probably individually numbered since the different wheels need slightly different angles on the suspension arms. I think I managed to do this right, without screwing up. Time will tell.

You are looking at all the part needed to make a complete wheel/suspension arm assembly. Two wheel halves, two rubber rings (the rings come with a rubber disk that has to be ripped out first, one of the rings above has the disc still in place.), two brass bearings, five screws, one suspension arm and one metal axle. The wheel axles come in two versions, 14 axles looking like the one above, and two axles for the idlers looking almost like the one above, although slightly darker and with a small notch in the wide part. Fortunately it is also slightly longer, witch made it easier for me to find the wheel/arm assembly where I had put the wrong axle, without having to completely disassemble all 8 assemblies I had managed to finish by the time I discovered that there were only one idler axle left.

Also on each wheel there is a hub cap, but I left them out temporarily, since I might want to paint a few details on the wheels, and then it is nice to have the hub cap out of the way.

This is a finished roadwheel. Only thirteen more to go. I managed 8 more, before I had to go to bed.

Day 4

With all the road wheels made I could not wait attaching them to the hull. After that it was just the simple job of attaching the gearbox and engine pack with three screws and then the sprockets with two screws each. Tamiya tells you to attach a plastic collar around the middle of the drive sprockets. It´s nothing I remember seeing on the real deal, so I left them off. I think the collar helps to prevent track shredding. I’ll try my luck without them for a while.

With the tracks on, a bit of posing is in order. It is not only large, now it is getting heavy too, with the drive train in place.

As I mentioned earlier, the turret front touches the air intakes when rotated. It also touches the handle on the front fuel filler caps. I got an idea on how to solve this.

I simply made a shim out of plasticard (think it´s 0.3mm). Not the nicest of cutting job above, but I settled for good enough, not German (or Japanese) precision. Dry fitting with the shim between the turret ball bearing and the turret solves the problem. The only problem with this solution I can think of, is that the turret drive gearbox will sit a bit higher relative to the turret rotation sprocket. Since we´re speaking of a fraction of a millimetre, and the large sprocket is at least 5mm wide I don´t think this is a big problem.

Now for some electrical work. See the empty connector above? I unpacked all the wiring from its bag, where it had until this point been untouched. I took all of the motor leads that was in the bag, and put them in the black speaker-box and screwed the box shut. Then I made the really shocking discovery that the black lead for the propulsive motor was missing. I looked in the bag, I looked in the box, I looked everywhere. No wire. I cursed and started thinking about where to get the necessary hardware to solve the problem only to find that the cable somehow had, without notice or asking for permission, fallen to the floor beneath my chair. This was not the last case of missing parts this evening.

Speaking of missing parts, I found that small ball from the turret ball bearing I lost the other day. I had been searching all over the floor for it when the ball bearing assembly accidentally split open before I had screwed it together. It turns out the ball had been hiding on the table.

After I had sorted out the various wiring troubles I moved on to spread a little light on things. Time to fix the lighting in other words. The kit has working headlights, tail lights, brake lights, convoy lights and shielded lighting. There is also an optional “rotating beacon” to put on the turret roof. When everything is working, it is possible to select various lighting modes, like normal use, shielded lighting, beacon on/off. The lighting is controlled by the DMD-07 computer. Electric signals are sent to a forward and a rear light box where LED´s are connected to strands of fibre optics. The black box on the photo above is the rear light box. The strands of fibre is held in place at the box with small rubber gaskets, and this was the next item to go missing. When assembling the box above a fibre and its associated gasket yanked free from the box, and the strand literally catapulted the gasket to anywhere from here to eternity. I was kind of certain that I´d never would find it, so I limited my search to the area close to the table and on the table itself, fully aware that the gasket could have catapulted itself to anywhere in my large living room, that doubles as a tank workshop for this project. I was planning on securing the strands missing their gasket with electrical tape later if needed.

I had been thoughtful enough to paint the reflectors of the head lights and tail lights with Alclad chrome. But I discovered that Alclad doesn’t take super glue well, the glue dissolved the chrome! I guess I’ll have do some touch up with Humbrol silver later. I have not yet glued on the clear glass, since I don´t want to risk them being fogged by the super glue.

Time to close the lid on the hull. At least temporarily. I will have to unscrew everything later to be able to mount the side skirts. But I want to screw the upper hull in place to be ready for test driving and to see if the problem with the turret touching the hull will disappear when everything is screwed down properly. There are a lot of wires travelling from the hull to the turret. Unfortunately Tamiya didn’t include a slip ring, so there will really be a limit of rotations that can be done with the turret, before having to rotate in the opposite direction. The user guide recommends a maximum of 360 degrees.

The upper hull is attached to the bottom with eight screws, so it is not something to be opened during day-to-day maintenance. Six of those screws are self tapping, which means that they should not be touched to much, since they might strip the plastic thread and come lose. With the hull screwed together and the turret screwed on to the ball bearing, and the ball bearing in turn screwed on to the hull the problem with the turret touching the hull was no more. I put the spacer I made aside, It might be needed later. But if possible, I rather manage without it.

One last thing. When I toyed around with the tank a bit after clearing the work area for the night something dropped from the track.

It´s the lost gasket from the lighting system. Well, I´ll fix that when I add the side skirts later.

Left to do now is the turret mechanism, with traverse, elevation and recoil mechanism. Not to mention lighting effects for machine gun and main gun, electrical wiring and installation of the DMD-07 computer. In other words, plenty of fun left. I hope to get my transmitter tomorrow also. I hope to be able to test drive this weekend.

Day 5

Today my transmitter arrived, and I wasted no time getting it up and running. The first step was to connect the receiver to the DMD-unit to the servo for gun elevation. I connected a fully charged battery and…not much fun happened.

The servo went to neutral, so that I could attach the servo arm at the proper angle. That was the whole purpose of this excercise, and checking that stuff worked of course.
I also calibrated the setup using the built in setup function in the DMD. It´s simply a matter of telling the DMD the range of the control sticks so that the DMD can configure itself properly.

When I was satisfied I went on to the various turret mechanisms.

First I assembled the gearbox for the turret traverse. It is made out of a motor with a worm drive, connected to two gears. The gear that connects to the turret ring has a “clutch” in order to save the gears from being stripped if somebody tries to rotate the turret by hand, or the gun barrel hits something while driving at speed. Not an unlikely scenario. Hitting a tree with the gun barrel is not uncommon in the full scale world, especially if the barrel is of the long variety that the Leo 2A6 has.

This is the recoil mechanism. When the main gun is fired, the gun barrel is pulled backwards, then returned to battery at a slightly slower speed.

The turret is starting to fill with electronics and cabling. The traverse mechanism and turret elevation sensor is mounted. Also mounted to the rear of the turret ring is a small micro switch (black and green cable). When the turret rotates towards the rear, the witch will hit a ridge in the black turret bearing part and depress. This will tell the DMD that the turret is travelling towards the rear, and the DMD will elevate the gun to clear the engine deck if needed.

This is a flash, a muzzle flash, literally. It will be stuck in to the barrel from behind and placed within the muzzle part. The plastic muzzle comes as a transparent part, and the instructions tells you specifically not to use primer on it.
I had trouble getting the flash in to the muzzle since it wanted to get stuck on the edge of the plastic part. I solved the problem by sticking fishing line from the muzzle end, punching a small hole in the orange shrink wrap where I tied the line. Then I could gently pull the flash unit through to the muzzle.

The gun is ready to be placed in the turret. Note the grey/white wires of the machine gun LED.

Now everything else is mounted in the turret. It is getting really crowded. To the rear is the DMD control unit. In front of the DMD sits the battery, a standard 7.2V NiMh RC-battery. In front of the battery to the left hand side sits the receiver. Modern 2.4GHz receivers are really small, which is a good thing here. On the other side of the turret sits a high voltage unit, that powers the muzzle flash. In front of the receiver the turret elevation servo is mounted, and the turret traverse mechanism sits in front of the HV-unit. Between the servo and traverse gearbox sits the main gun and its cradle. All components have their own wires. From the hull comes the four motor wires, a speaker wire and two wires for the lights.

It took some trial and error, but now the cables are tucked away enough that the turret roof fits. There are some nice pictures suggesting how the wires should be placed, and I ended up doing something similar to what the instructions suggest, I think. The pictures in the instructions are not really that helpful.

Some test driving!

This is a long exposure of the main gun firing. When the gun fires the tank jerks from the “recoil” as you can see on the motion blur on the tank. This recoil is of course entirely fake, and is created by the DMD by backing the tank a short distance. It´s not smart enough to know where the gun is pointing, so the “recoil” always pushes the tank backwards, even if the gun is pointing rearwards.

Now that the tank is finished mechanically, all that is left is basic modelling – which is the hardest part. I have not yet decided on how I want the finished result to look. To weather or not to weather is the question. I don´t want this to look like a typical RC toy, but I don´t want to over do it either. Whatever finish I do, it must be durable enough to manage being handled and driven around. Also, I believe there will be some natural weathering on this one too.