RC Tank Warfare community hobby forum

In order to design the best motorization, i decided to create a simple proof of concept (POC) so that i can study it and improve without spending 2 years on this. So, in one afternoon, i was able to do the following;

Option A was discarded as being too weak. Efforts concentrated on Option B with the 1/10 gearbox and RS540 motor.

POC construction as follows;

Reused the discarded plastic gear and the leftover from the metal shaft. A hole for the connection to the drive shaft was made, and a anchor pin was inserted at the proper location for the gear. Being aluminum, this took at few minutes.
Basic design for the two main drive shafts for front and rear units.
A simple mount is designed.
And mounted with a few drops of superglue. As this is a POC, only the final design will be made solid later.
I had to remove a reinforcement bracket from suspension unit B and C in order to accommodate the drive shaft to the gearbox.
View of the two main gears now linked.
Both units are now installed.
The gearbox is mounted on a temporary basis just to check the integration and how things runs. The motor is connected to the Clark TK40.
Front
Rear
And here is a short video of the running test of the Proof of concept. It’s not really smooth, the gears are new and the running is rough. Various improvements will be made on the next version. I can provide additional room for the motor drive shaft to be extended, more strait and lower the gearbox. Works ok at slow speed, allowing the GTK to likely become a crawler as well.



continuing on following post.

The motorization with the 1/10 gearbox and 540 motor has a lot of potential, and quite affordable.
Metal gears were ordered to replace the plastic one used on the POC.
Regards, Louis

Hi,

The motorization of the GTK Boxer is done.

Following the POC yesterday, i have reworked one of the axle gearbox that was giving problems. The four screws shown below were screwed too tightly and putting pressure on the pinion gear... The noise was unmistakable but it took me a while to find the cause.
I shortened the shafts to the main drive gears by eliminating a planned third support with a ball bearing. Testing showed that the shaft are ok with 2 supports as shown, giving me back a few priceless millimeters, allowing me to lower the motor and main gearbox.
A crude mount was designed for the main motor/gearbox. It will be reinforced later after the steering is designed.
A small bolt with a washer against the flanged ball bearing at the tip is holding the shafts in place, squeezed between the two ball bearings. I am making use of the pre-drilled hole and bolts at the tip that came with the leftover of the upgraded metal drive shaft. Never discard anything...
Now i only have to replace the plastic gear by a metal one when it arrives, then the mounts will be reinforced.
It now runs more smoothly and the following demonstration is done at low speed at first, slowly increasing to top speed, forward and reverse. It is a fast, cheap and simple design. I ran it for 10 minutes without problems. The real Boxer has a top speed of 103km/h, It seems this will do the job well, from crawling to top speed.



Next step is to design the steering.

Regards, Louis

I'm ashamed to admit that I nearly skipped over this thread since I'm not interested in current-generation military vehicles. What a mistake that would've been!

Terrific work with the motorisation Louis, it's an impressive feat of engineering and a work of art all in one. I really like the way you've dropped the axis of rotation down to the driveshafts. Now if only the outside were a BTR-70 or Sd.Kfz. 234.

Just Genius..........what else is there to say ...............

HERMAN BIX wrote:Just Genius..........what else is there to say ...............

That about covers it!

Barry

Thank you Raminator, Herman and Barry !

This build is really fun. WLTOYS provides cheap, high quality and full range of metal upgrade parts that can be readily used to experiment on wheeled armored vehicles. It takes a few days of work to get something together. And plenty of cheap replacement parts if something goes wrong. I have a few good Chinese eBay sellers that use SpeedPak delivery, i can get stuff in within two weeks. Much better that my next build kit who has been stuck in a German airport for past 4 weeks.
Regards, Louis

Continuing with the build.

Chris did a bad joke on me. I assumed the positioning holes for the suspension were centered with the external body. They are not... I had a small shock when i dry fit the skirts and noticed the misalignment. Very annoying, i had to reposition the suspension module A and B, reinstall them more forward and redo the shaft integration. I few hours of rework. Be warned. Make sure to align the suspension with the skirts first, no assumptions.
Anyway, it gave me the occasion to complete the metal upgrades for the steering.
And also for the adjustable suspension bars, replacing the plastic bars. This upgrade is mandatory for this build.
Overview of the repositioned and upgraded suspension.
This built is quite fun. If you are starting to be fed up with RC tanks while you are doing your sixth Tiger or Sherman..., doing a 8x8 wheeled vehicle is an entirely new world.
The adjustable metal steering and suspension bars are mandatory in order to correctly set the pitch and directions for each wheel.
Frontal module A. Notice the steering going towards the back.
Middle suspension module B.
Overview of the steering solution. Each steering module has its own regular size servo connected to a push rod, both are working in tandem with a Y connector to channel 6 assigned to the VRB knob for driving the vehicle. The gearbox and motor were dismounted for the task.
Starting body construction.

The tires have arrived.
I could modify and reused the plastic rims if i have to.
Dry fitting the tires to see if they are of the right size. They look good with the GTK 3D printed hub caps from Ludwigs. Cannot find better matching tires for the price.
I have these narrower metal rim on order, they come with larger Hex mounts. I am crossing my fingers that it will work. Otherwise, i will have 8 plastic rims to modify.
Comparing the GTK Boxer with the Metal Origins SdKfz 234/2 Puma being build in parallel, both 1/16. I am surprised how big the GTK is compared to the much smaller and narrower WW2 Puma.
Regards, Louis

It's amazing how big these modern IFVs are. I remember your Marder was nearly as big as a Leopard 2, so the Boxer is going to dwarf any WW2 vehicle.

A shame about the alignment issues with the kit but if anyone could have fixed it, it was you!