RC tanks anyone? part 2: 1/35 scale Tigers

Around the time this board was just getting started, I was already moving away from 1/6 projects and investing lots of time and money on an ambitious RC project that I have yet to finish. One of my most cherished models from childhood was the line-control motorized Tamiya Tiger I in 1/35, which I built when I was eleven and which I still have. With the state of RC today, I thought I could figure out a way to refurbish it and make it fully RC, but after some research and thought I decided to start from scratch and build some new kits. But I was still stuck on that old kit which although filled with inaccuracies was designed with motorization in mind. Tamiya never replaced that mold until the late 90s, when they finally came out with an early Tiger I that was scaled correctly and had up to date detailing which the original never had.

Anyway, to make a long story short, I bought several of the old kits cheap, and then bought several of the newer generation RC tanks to provide the electronics and motors (I used T-34s, ironically). The dumb thing was, Tamiya had already put out RC Tigers based on the new generation kits, and all I had to do was update the electronics on those, but I persisted in using the ancient kits, because nostalgia, I guess? I ended up buying the new (static) kits as well, to provide details as well as updated turrets which were much more accurate. By the end of all the acquiring, I spent well over $1000 getting all these kits old and new, but had enough to do 4 Tigers, and have only completed the mechanicals for two of them. The ultimate goal is to model them based on 4 specific Tigers in Schwere Panzer Abteilung 503 during the Kursk campaign, but that modeling is a ways off.

Here's the model that started it all, flanked by some of the newer kits that were going to start the project (still in pretty good shape for being almost 40 years old):

Tamiya had created two RC systems in the newer generation (their first attempts were very basic and somewhat crude): one with an infrared "battle system" complete with sound, rotating turrets, gun elevation, and muzzle flash; the other with the same basic gearboxes and motors, but without the sound and battle system, and also without the gun elevation and muzzle flash. I got T-34s in one of each. I decided I was going to use the newer gearboxes from the battle system tank in one, but use the old metal gearbox with the non-battle system in the other.

Here are some pics of the battle system build. This system features an integrated radio/receiver as part of its electronics.

Cutting up the T-34 chassis to fit in the Tiger:

Adapting the Tiger chassis to fit the T-34 components:

Battery box and gearbox mounts installed:

The gearbox mount slides fore/aft and acts as track tensioner:

The turret system for the Tamiya RC units is a sophisticated self contained motor/gearbox unit that drives the whole turret ring, and in the battle system unit has an ingenious worm gear motor that raises and lowers the "breach" of the main gun. Adapting this to fit the tiger was a challenge, as was adapting the main gun to fit the fiber optic flash unit.

Here's the turret unit installed, along with the drive motors on the left and the receiver/control board on the right. As you can see it's a tight fit.


Work on the gun and turret:


The turret installed with the turret motor unit mated. The geometry has to be perfect, so there was a lot of adjustments needed for the brackets. You can see in the above picture that because the sponsons are angled, the T-34 brackets had to be sanded at an angle to fit.

On the other Tiger, without the battle system, I still wanted one with an elevating gun, sound, and flash, so I had to find another control board system that could do this for me while using the drive systems of the Tamiya. I found a small company in HK that specialized in 1/35 scale electronics and purchased a unit or 3. The trickiest thing was to figure out how to fit a small servo to move the gun:

I drilled a large hole in the top cover plate of the motor unit to thread the wiring through, and you can see the LED fitted into the gun "breech". A nylon washer provided the perfect fit for the 3mm LED.

You can see through the hatch that the tolerances for the servo while rotating around the drive unit are very tight.

And here's the completed mechanicals for the second Tiger. Notice the old-style gearboxes from the 70s on the left (with new motors, of course), and the control boards and receiver on the right. Battery will be supplied by a tiny one cell LiPo battery of 700 maH. There's more room in this one, but things are less tidy.

Speaking of battery, I forgot to mention the battle system Tiger runs on 4 AAA batts, which take up a ton of room. Notice the speaker grill on the underside as well.

Also, I forgot to include a pic of the gearbox/motors for this tank. They are a lot quieter than the old metal ones.

That's pretty much it for build pics. I wasn't so meticulous in documenting every step on this build, it was so complicated I just didn't have the energy. Since they are unfinished I don't have any beauty shots of the tanks, but I do have a video that shows both tanks doing their thing.

At the end I drive both tanks simultaneously, one controller in each hand, trying to keep them in formation. Not easy to do, but fun nevertheless.



This was by far the hardest RC project I've ever done. Getting everything to fit in that small a space is really challenging. Someday, I'll get the motivation back to proceed with the scale modeling part and finish these.

tankgirlfuzzy wrote:
At the end I drive both tanks simultaneously, one controller in each hand, trying to keep them in formation. Not easy to do, but fun nevertheless.

I can imagine it's not easy to operate two at the same time, but you made it look very realistic.

Do you add the sounds to the video afterwards? I'm asking because I used to do model railroading (still have it, but haven't touched it in 4 or 5 years). In modelrailroads most trainmodels are digital these days. This basically means every train has a decoder built within, and the track always has power. You have a basic unit/controller (or computersoftware or app on your phone) which sends signals to the decoder, so the decorder determines what the train is doing based on those signals.

There are also decoders with sound, those trains have also a little speaker built in, so they can blow their horn, you hear the sound of the engine or the announcer can tell the train is about to leave.

The decoders can also be bought separately, so old trains can be digitalized. I think in some of the sound decoders you can also upload new sounds (MP3's usually). So if you're currently adding the sound to the video, maybe you are interesting in actually adding the sound to the model. I'm not sure if it would be easy to use it in tank, because the currency has to be right frequency. This probably means regular batterypower wouldn't suffice. I could imagine that this technology crosses over into the modelling of RC units. So you might want to look into it.

There should be enough room in the models. After all they built them into N-scale locomotives, which are a lot smaller.

I guess I wasn't clear, but yes, both models have integrated sound units (in one of the pics I show a speaker grill on the underside). That means all the sounds for the functions (cannon, motor, turret sounds) are synchronized with the movements, and you can also control the volume. And, actually the battery power from the 4AAA (6v) and the 1s lipo (4.2v) is plenty to drive the sound on these units, they are very loud for their size, though not as loud as the 16th scale King Tiger. Space is tight, though, even for those little speaker boxes I used (not very visible in the pics because they are underneath everything).

Cool. Reading back, I see you mentioned it in your second post.

Another cool build I had to take my time to digest. Really impressive.

Thanks Stryker!

These are awesome!!
I used to build 1/16 scale RC tanks in a former life So this hold some interest for me. Almost all my 1/16 tanks are now gone to new homes, but I still have some 1/72 IR remote controlled tanks from a company called Waltersons that are fun.
Not something I am likely to go back to now, but nice to see someone playing with RC tanks all the same. Thanks for posting.

Paul

scalawag wrote:These are awesome!!
I used to build 1/16 scale RC tanks in a former life  So this hold some interest for me.  Almost all my 1/16 tanks are now gone to new homes, but I still have some 1/72 IR remote controlled tanks from a company called Waltersons that are fun.
Not something I am likely to go back to now, but nice to see someone playing with RC tanks all the same.  Thanks for posting.

Paul

Thanks scalawag, and welcome back! (I do remember you back in the day!) I also have three of those Walterson's tanks, but unfortunately only one ran well out of the box (the Abrams). They are fun but I do like the ability to scale out the bigger tanks with details and electronic bells and whistles.

You mentioned 1/16 so I'm assuming you saw my GuP KT on that other thread. Would love to know what you think and if you have any input/advice on those bigger tanks.

tankgirlfuzzy wrote:

scalawag wrote:These are awesome!!
I used to build 1/16 scale RC tanks in a former life  So this hold some interest for me.  Almost all my 1/16 tanks are now gone to new homes, but I still have some 1/72 IR remote controlled tanks from a company called Waltersons that are fun.
Not something I am likely to go back to now, but nice to see someone playing with RC tanks all the same.  Thanks for posting.

Paul

Thanks scalawag, and welcome back! (I do remember you back in the day!) I also have three of those Walterson's tanks, but unfortunately only one ran well out of the box (the Abrams). They are fun but I do like the ability to scale out the bigger tanks with details and electronic bells and whistles.

You mentioned 1/16 so I'm assuming you saw my GuP KT on that other thread. Would love to know what you think and if you have any input/advice on those bigger tanks.

Thanks tankgirlfuzzy,

The Waltersons 1/72 tanks are a bit finicky out of the box and to be honest don't run fantastically, but there are some tweaks I made that helped a little with this.  Chiefly I added some weight.  I am always a proponent of RC tanks being 'heavy'.  Yes you have to beef up the mechanics a bit to handle the weight, but to me they just don't look right when they are moving if they are too light.

I did see your GUP KT and thought you did a great job with it.  I have been out of RC tanks for too long now to be current on what the latest products and ideas are in that hobby, but you seem to have covered pretty much all I would have done.  The only difference, I would have used an IBU 3 control unit for it's really easy computer set up and features, but I understand that these are no longer being made so an Elmod makes sense.

Great to hear from you.

Paul