T'Rex Tank Chassis

You better call Dr. Grant because we've got a T'Rex! If you thought our previous robot chassis were beefy and rugged then you haven't seen this. The T'Rex Tank Chassis is a full metal all-terrain robot platform designed to handle the most extreme driving conditions possible! This chassis offers the best of two worlds: It takes almost no time to go from un-boxing to rolling chassis, but it's also ready to be expanded on and makes great base stock for a serious 'bot.

The T'Rex Tank Chassis is equipped with two independently driven 12V gearmotors with a typical current rating of 4A (No Load at 1.3A & Stall Current at 11A with a 5000mAh LiPo Battery). Each motor drives one tank tread that offers three lower wheels that help to improve traction and reduce shock to the main body and controller. On that note: the gears, tracks, suspension struts, and wheels are all made of die cast zinc which offers a fair amount of corrosion resistance reducing the constant need of maintenance and upkeep.

Inside the T'Rex Chassis' aluminum body you will find plenty of space for your motor controller, batteries, sensors, and anything else you could possibly need space for. Two top panels can be easily removed via four spring catches mounted in between the wheels. Additionally, the front hinged cover plate can be removed to affix any large sensor(s) to your T'Rex, you can even attach a custom plate to fit your preference (we're waiting to see someone 3D Print a T-Rex head and attach it to one of these guys)! Since the chassis does have a full aluminum body it will block any electrical noise and radio signals so you will need to attach any receiver or transmitter to the outside of the T'Rex.

We have tested the Monster Moto Shield (not included) with this chassis. The driver works just fine with the T'Rex when coupled with an Arduino development board.

Weight: 3.7Kg (8 lbs)

  • All-Terrain
  • Anodized Aluminum Body
  • Anodized Zinc Tracks, Struts, and Wheels
  • 2x 12V DC motors with all metal gearboxes
  • Motor Specifications:
    • Typical Voltage: 12V
    • No Load Current: 1.3A
    • Typical Current: 4A
    • Stall Current: 11A (Measured using a 3S 5000mAh LiPo battery)
  • 70mm (2.75") Clearance with Low Center of Gravity
  • Removable Front and Top Panels with Quick Spring Release
  • 355 x 175 x 130mm (14" x 6.8" x 5")

T'Rex Tank Chassis Product Help and Resources

Replacement Parts

Have you damaged a gearbox or motor shaft on your T'Rex Chassis? Have no fear, Dagu has replacement parts available on their website.

Replacement Motor Shaft

Replacement Gearbox with Motor Shaft

1 of 1 found this helpful:

Alternative to the T'Rex Motor Controller

Some of our customers have found a reasonable alternative to the T'Rex Motor Controller with this SaberTooth Motor Driver.

Core Skill: Robotics

This skill concerns mechanical and robotics knowledge. You may need to know how mechanical parts interact, how motors work, or how to use motor drivers and controllers.

2 Robotics

Skill Level: Rookie - You will be required to know some basics about motors, basic motor drivers and how simple robotic motion can be accomplished.
See all skill levels

Core Skill: DIY

Whether it's for assembling a kit, hacking an enclosure, or creating your own parts; the DIY skill is all about knowing how to use tools and the techniques associated with them.


Skill Level: Noob - Basic assembly is required. You may need to provide your own basic tools like a screwdriver, hammer or scissors. Power tools or custom parts are not required. Instructions will be included and easy to follow. Sewing may be required, but only with included patterns.
See all skill levels

Core Skill: Electrical Prototyping

If it requires power, you need to know how much, what all the pins do, and how to hook it up. You may need to reference datasheets, schematics, and know the ins and outs of electronics.

3 Electrical Prototyping

Skill Level: Competent - You will be required to reference a datasheet or schematic to know how to use a component. Your knowledge of a datasheet will only require basic features like power requirements, pinouts, or communications type. Also, you may need a power supply that?s greater than 12V or more than 1A worth of current.
See all skill levels


Looking for answers to technical questions?

We welcome your comments and suggestions below. However, if you are looking for solutions to technical questions please see our Technical Assistance page.

  • Member #1352825 / about 4 years ago / 1

    Probably a stupid question but.. do you think a Romeo V2 Board would run the motors?

  • Member #1114068 / about 5 years ago / 1

    The gears are said to be full metal, but when i zoom in on the picture they appear to by plastic... Could someone answer this for me?? thanks!

  • -------------------- Tech Support Tips/Troubleshooting/Common Issues --------------------

    Monster Moto Shield

    After testing it with the Monster Moto Shield, the current pull was about ~2.73A to ~3.89A depending on how hard I was running the motors with a benchtop power supply. The motors were running for 5 seconds forward and backwards. The benchtop power supply would spike to ~3.8A briefly when the motors changed direction. Make sure that you have an RC LiPo battery or a power supply that is able to output a lot of power. The motor driver appeared to stay cool after the tests.

  • dbc / about 8 years ago / 3

    Any way to attach encoders to the motors? Doesn't look like the motors have tail shafts.

    • OddBot / about 8 years ago / 1

      The gearbox is easily disassembled and it is fairly easy to add either optical or magnetic encoders to the gears.

  • JD Roy / about 8 years ago / 3

    Now to add this... And I'll have sentry bots for my villain lair!

  • D_C / about 8 years ago / 2

    The top doesn't appear to be, but how water resistant is this? At least if the bottom half is submerged in water?

    • OddBot / about 8 years ago / 1

      The body is not water proof. To begin with there are holes for the drive shafts to poke through so you should mount your electronics in a sealed plastic bag or waterproof housing if you want it to go in water.

      The chassis is all aluminium, zinc or brass so it has high corrosion resistance. Only things like screws and springs are steel but they are nickle plated. As long as you waterproof your electronics then you can just use a hose to wash it and then add some dry lubricant once it's dry.

      You can see the prototype videos here: https://www.youtube.com/watch?v=Qyzs-LxoyzQ

  • Member #502457 / about 8 years ago / 2

    I could use some clarification on the zinc wheels. On boats we use zinc to prevent corrosion because the zinc corrodes more easily than the other metals. What is it about the zinc that makes it good for corrsion resistance?

    • Circuitsoft / about 8 years ago / 1

      Zinc, by itself, is very corrosion resistant. When you put a zinc plate on a boat, it acts as a battery, and induces current flow through the water that prevents oxygen ions from bonding with the hull, forcing them to bond with the zinc plate instead. The remaining hydrogen ions don't damage the iron hull of the boat.

  • Member #518130 / about 8 years ago / 2

    Much as I hate to ask this of such a perfect product: is there some soft plastic treads I could buy for this to make it less loud and not damage the floors? Some of us have wives... :)

    • Member #563632 / about 8 years ago / 1

      The tracks, idler wheels, and toothed sprocket are all from Tamiya's 1/16th scale German Tiger 1 RC/model tank. So yes, you can buy plastic tracks for it. Try www.tankzone.co.uk.

  • krazcy_ivan / about 8 years ago / 1

    Is there a replacement for the top cover available separately?

  • Member #243571 / about 8 years ago / 1

    I would love to see a comparison between the T'Rex and the Wild Thumper in different terrain and conditions. For example, I have seen in the product video for the Wild Thumper, it can fairly easily climb up curbs and small steps if approached at an angle. However, I can't seem to find anything on the intarwebs demonstrating such capability for the T'Rex -- and given the substantially different suspension between the two, I am also interested in seeing how these two platforms compare in dealing with rough terrain and obstacles. Any info or videos would be appreciated.

  • JellyFish / about 8 years ago / 1

    Could this climb stairs? Working on a rover-type project.

  • Member #445152 / about 8 years ago / 1

    Anyone know of a source for replacing just the brass bushings in the gearboxes, or a suitable replacement bearing? Mine have completely worn out in just a few hours of running after upgrading to the steel gears bought off Ebay (“HENG LONG tank gearbox” on ebay).

  • Member #429971 / about 8 years ago / 1

    Does the T'Rex beat the Wild Thumper 6WD in traversing obstacles?

    • OddBot / about 8 years ago / 1

      It depends on the terrain and the payload. The T'REX tank, like all tracked vehicles can throw a track under some circumstances but has better traction in sand, snow and mud.

      The T'REX depends on the spring tension of the suspension to keep the tracks tight but excessive payloads will cause the springs to compress. It was originally designed to have a 3S LiPo, The T'REX controller and a Raspberry Pi inside with a pan/tilt and camera up top.

      The Wild Thumper can carry bigger / heavier payloads and never throw a track but it is more likely to get bogged in sand, snow or mud.

    • they're different. I' d take the thumper for various terrains, but I'd take the t'rex for ruggedness. it's more sealed up. each has their purposes.

  • Spinerex / about 8 years ago / 1

    What is the gauge of the wires coming from the two motors?

  • Spinerex / about 8 years ago / 1

    What happened to the estimate of July 19th?

  • 53RG10 / about 8 years ago / 1

    Why does it cost almost the double on dagu website?

  • richkappler / about 8 years ago / 1

    What kind of payload will this handle?

    • OddBot / about 8 years ago / 1

      As the kit comes, maybe half a kilo. Adding additional springs to the suspension will allow heavier payloads.

  • BoWingo / about 8 years ago / 1

    It's shown in the user manual, but it should probably be noted in the product description as well, that the 175mm dimension is for the width of the body, not including the tracks. With the tracks included, the overall width of the chassis is 265mm (10.4").

  • CraigTheCoder / about 8 years ago / 1

    What are some recommended batteries (Sparkfun or otherwise) to use with this chassis and the latest T'Rex controller? Also, any suggestions for a simple RC receiver board to use with said configuration just to get some basic functionality up and running?

    • OddBot / about 8 years ago / 1

      With the prototype I used a 5000mAh 3S Lipo. It all depends on what kind of run time you want between charges.

    • c.burgess.7 / about 8 years ago / 1


  • Member #353680 / about 8 years ago / 1

    Actually anodize is usually found in aluminum. You will find the tracks are cast zinc, lower melting point for casting and not as problem prone as aluminum.

    • OddBot / about 8 years ago / 1

      Yes the tracks are cast zinc but an anodizing process is used to color the tracks and give them a shiny finish.

  • khearn / about 8 years ago / 1

    I'm not clear on what exactly "anodized zinc" is. Usually when one sees "anodized", it means it's mainly steel with a zinc plating applied by a process known as anodization. Is that what this is, or is it zinc with some other metal anodized onto it?

    • ShapeShifter / about 8 years ago / 1

      Galvanized steel has the zinc coating you're thinking of, where the zinc is either electroplated, or the steel is dipped in molten zinc. Anodizing is a process usually done to aluminum which creates a corrosion resistant hard smooth oxide layer. Besides aluminum, it can be done to several other metals, including zinc.

    • Member #353680 / about 8 years ago / 1

      Actually anodize is usually found in aluminum. You will find the tracks are cast zinc, lower melting point for casting and not as problem prone as aluminum.

    • Member #353680 / about 8 years ago / 1

      Actually anodize is usually found in aluminum. You will find the tracks are cast zinc, lower melting point for casting and not as problem prone as aluminum.Enter a reply...

  • Nathaniel D / about 8 years ago / 1

    Is it at all possible to purchase the motor/gearbox combo separately? Or does anyone know what motors this tank uses?

    • Nathaniel D / about 8 years ago / 1

      Found it! Thanks a bunch!

    • wanao / about 8 years ago / 1

      search for "HENG LONG tank gearbox" on ebay or aliexpress and that's the gearbox you need. the motors are brushed w/ 2mm shaft. The pinion gear are 48p 10T. I recommend upgrade the gearbox to steel gear as the alloy gear will worn out pretty fast.

    • Nathaniel D / about 8 years ago / 1

      I've had no luck finding a matching motor or gearbox on their website.

    • Lion XL / about 8 years ago / 1

      They have the same motors and such on their website.

  • LED addict / about 8 years ago / 1

    Best demo ever!

  • Member #403458 / about 8 years ago / 1

    Any chance of offering just the tracks?

    • dpitchfo / about 8 years ago / 1

      Try: http://www.tankzone.co.uk/cart/hl_kt.htm

      They have alot of parts for RC Tanks.

  • PostmasterSteve / about 8 years ago / 1

    $2499.50 later: "They're moving in herds ... they do move in herds..." Spared no expense ! :)

  • lpgatlin42 / about 8 years ago / 1

    okay, I will say it. This is wicked!

Customer Reviews

3.5 out of 5

Based on 6 ratings:

Currently viewing all customer reviews.

5 of 5 found this helpful:

+5 as a robotics platform, -several million for the junk gearboxes

As a robotics platform, it's everything you could need. Room enough for two 5000 3S LiPos, the T-Rex driver board, and maybe a Raspberry Pi. On top of all that, you can strap radios, cameras and the like to the top plate, so payload space is ample. The spring-loaded catches on the sides make accessibility a breeze, and because the access panels are split into two sections, you can just hinge open the front to change the batteries. Build quality feels good on the tracks and wheels, the suspension is a little floppy for my taste but that's not a big issue, and the main chassis is made of solid, thick steel. However. And thats a big however. After you receive this, get rid of the worthless included gearboxes. (I'm currently waiting on the steel version of the same gearbox, see comments for details) When I got mine, I set all the electronics up and threw a half charged 2200mAh battery in it. By the time I had driven up and down the sidewalk twice, about 5 minutes of drive time, there was a wretched grinding sound coming from one of the gearboxes. By the time it limped back to base, 6 minutes after first power-on, the left tread was completely disabled - the bushings in the gearbox had worn down enough to bring the gears out of alignment and make movement impossible. This happened without a heavy payload or intense load on the treads - I was running the bare minimum weight needed to move the thing, and rolling down a smooth, flat sidewalk.

Long story short - it's a great platform, especially for the price, but is crippled by a junk powertrain that will need replacing in the hour of operation, if you're lucky.

I'm really sorry to hear you had issues with your gears. We have seen some other units with a similar issue. Please contact us for assistance. We'd like to help you out with this issue. https://www.sparkfun.com/returns

1 of 1 found this helpful:

Such an awesome looking product but didn't even work out of the box

I was so excited to get this and took it out of the box. Every ounce as heavy duty as it looks except I can't even use it. The output shaft on the right tank track is bent so far you can't even spin the track manually or under power. Seeing another review below with the same problem looks like T'Rex has horrible quality control. Can't wait to get an email back from spark fun and get this thing working. It's suppose to be an important player in my wedding!

--updated: Sparkfun sent me a new output shaft in like 2 days! YOU GUYS ROCK! I replaced the shaft this week it looked a lot worse once I removed it then I initially thought. it was bent a good 30 degrees. After getting it together the tank now runs but the Right gear box is still messed up. It has a lot more resistance in the gears and still seams binding compared to the Left gear box. I'm going to take the entire gear box apart and measure everything with a caliper and micrometer to see what is out of wack but it's still sad that it's an barely usable product. Once again for such a heavy duty tank having an all plastic gear box is kinda cheezy.

Updated 7/30/15: I can't say enough good things about Tech support and Customer Service at SparkFun! Tim helped me though all the bent gear shafts and got me up and running with replacement parts. I am now happy to say I have a fully functional T'Rex chassis. Sparkfun replaced the entire gear box on the right drive unit and now the T'Rex works flawlessly. Count me in as a customer for many more years! I do have a correction to make that the gears are in fact metal and I was mistaken before.

I will contact you directly to help resolve this matter. For future support with issues with your product, please contact us directly. https://www.sparkfun.com/support

1 of 3 found this helpful:

Worst deal I did with Sparkfun !

No Driver board, useless piece of hardware At least you could have sent inside the package recommendations for a driver we could purchase.

Good design, additional efforts needed

One of the bearings wasn't in place and it was hanging in the chassis. One of the motors wasn't mounted properly but SparkFun sent me a replacement and spare parts and all was fixed.

Potential is there but the product itself is rough

The good: it's a solid chassis that easily holds all the electronics.

The bad: I still haven't been able to get it running. Right out of the gate the right track barely moves. Hooked up to a 3S 8800mah battery and the Trex controller the chassis veers to the right. When tested the right gearbox is under considerable strain it seems. Using my benchtop power supply I ran both motors at the same 11.2V and saw the right track was not only louder but was using a lot more current.

I saw the other reviews that mentioned similar issues but figured those were from years ago they had to have fixed it by now. Sadly no. So now I'm scrambling looking for a replacement gearbox.