Custom Built 8x8 With Tonka Cab

[12MPG]

Most of this hobby for me is in building vs. driving although I do enjoy driving them. I wanted an 8x8 but the HG comes already built. The Cross RC is a budget buster and is still just following instructions. What we have here is an 8x8 using aliexpress parts, misc. axial parts, and stuff I had sitting around.

It comes in at 31" L, 10" W, 11" H and weighs about 14 LBS.

<a data-flickr-embed="true" href="https://www.flickr.com/photos/63764171@N07/51281693358/in/dateposted-public/" title="IMG_0180"><img src="https://live.staticflickr.com/65535/51281693358_7d31c212be_z.jpg" width="640" height="480" alt="IMG_0180"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

 

[12MPG]

I have no idea of the proper way of measuring flex with on an 8x8. This does pretty well with the wheels at the corners still on the ground.

<a data-flickr-embed="true" href="https://www.flickr.com/photos/63764171@N07/51282539175/in/dateposted-public/" title="IMG_0170"><img src="https://live.staticflickr.com/65535/51282539175_b571d65fb5_z.jpg" width="640" height="480" alt="IMG_0170"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

<a data-flickr-embed="true" href="https://www.flickr.com/photos/63764171@N07/51282539230/in/dateposted-public/" title="IMG_0168"><img src="https://live.staticflickr.com/65535/51282539230_7d8d3bfca3_z.jpg" width="640" height="480" alt="IMG_0168"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

<a data-flickr-embed="true" href="https://www.flickr.com/photos/63764171@N07/51282247364/in/dateposted-public/" title="IMG_0163"><img src="https://live.staticflickr.com/65535/51282247364_ddb145ca2d_z.jpg" width="640" height="480" alt="IMG_0163"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

 

[12MPG]

Axles

The axles are HG axles because they were the easiest/cheapest option for a pass-through steering axle. They came with bearings the pumpkin and I replaced the bushings at the end of the housings with bearings.

<a data-flickr-embed="true" href="https://www.flickr.com/photos/63764171@N07/51281692168/in/dateposted-public/" title="IMG_4518"><img src="https://live.staticflickr.com/65535/51281692168_0486fccdd6_z.jpg" width="640" height="480" alt="IMG_4518"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

 

[12MPG]

Front Suspension

The front suspension was build using misc. brackets from aliexpress and cutting links in half, re-tapping them, and bolting them on. It is a y-link setup with plastic Axial y-links that I shortened.

<a data-flickr-embed="true" href="https://www.flickr.com/photos/63764171@N07/51281514021/in/dateposted-public/" title="IMG_4542"><img src="https://live.staticflickr.com/65535/51281514021_3f11da77ce_z.jpg" width="480" height="640" alt="IMG_4542"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

<a data-flickr-embed="true" href="https://www.flickr.com/photos/63764171@N07/51281692978/in/dateposted-public/" title="IMG_4509"><img src="https://live.staticflickr.com/65535/51281692978_98b90568f0_z.jpg" width="640" height="480" alt="IMG_4509"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

<a data-flickr-embed="true" href="https://www.flickr.com/photos/63764171@N07/51282247524/in/dateposted-public/" title="IMG_4545"><img src="https://live.staticflickr.com/65535/51282247524_fe71898f68_z.jpg" width="640" height="480" alt="IMG_4545"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

 

[12MPG]

Chassis

The chassis is comprised of a aliexpress axial style frame with extensions on the front and rear. The aluminum frame that makes up the flatbed stiffens it up. I forgot to take photos of just the chassis as I was building this. The shock towers are just some aluminum SCX2 pieces again off aliexpress.

<a data-flickr-embed="true" href="https://www.flickr.com/photos/63764171@N07/51281514376/in/dateposted-public/" title="IMG_4519"><img src="https://live.staticflickr.com/65535/51281514376_74e5583f55_z.jpg" width="640" height="480" alt="IMG_4519"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

 

[12MPG]

Rear Suspension

The rear suspensions is also a y-link setup using more misc. brackets. Both the front and rear ride on 110 MM springs.

<a data-flickr-embed="true" href="https://www.flickr.com/photos/63764171@N07/51282246229/in/dateposted-public/" title="IMG_4511"><img src="https://live.staticflickr.com/65535/51282246229_07106d6cf7_z.jpg" width="640" height="480" alt="IMG_4511"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

 

[12MPG]

Motor & Transmission

The motor is a Goolsky Surpass Hobby 550 35T Brushed Motor. The transmission is a 2 speed from aliexpress which I assume is a knockoff off of some other company. The difference in speed between the high and low gears is significant. It is shifted with a 9KG servo.


<a data-flickr-embed="true" href="https://www.flickr.com/photos/63764171@N07/51281693128/in/dateposted-public/" title="IMG_4507"><img src="https://live.staticflickr.com/65535/51281693128_ec81fdb297_z.jpg" width="640" height="480" alt="IMG_4507"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

 

[12MPG]

Steering

Getting the steering to work on the second front axle was a bitch and there is some bump steer but it doesn't seem like enough to matter on a rig like this. Each axle has its own 35KG steering servo. One of them is run off a BEC just to make sure it has enough power.

<a data-flickr-embed="true" href="https://www.flickr.com/photos/63764171@N07/51282245609/in/dateposted-public/" title="IMG_4517"><img src="https://live.staticflickr.com/65535/51282245609_c69a218523_z.jpg" width="640" height="480" alt="IMG_4517"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

 

[12MPG]

Electronics

I went as cheap. This is a YSIDO 60A ESC and the transmitter/receiver was also a cheap unit. The BEC is something I already has sitting unused.

<a data-flickr-embed="true" href="https://www.flickr.com/photos/63764171@N07/51281691508/in/dateposted-public/" title="IMG_4547"><img src="https://live.staticflickr.com/65535/51281691508_2c6eeeced0_z.jpg" width="640" height="480" alt="IMG_4547"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

 

[12MPG]

Additional Photos/Information

The whole truck cost approx. $550 to build including the transmitter and receiver. The most expensive individual item was the transmission. I think I could have built it for under $400 using more of my boneyard parts but i really wanted to have the two speed transmission because this thing is heavy. It drives quite well for an 8x8 and the turning radius is smaller than expected. The approach angle of the Tonka cab is not ideal but I have other rigs for real wheelin'.

<a data-flickr-embed="true" href="https://www.flickr.com/photos/63764171@N07/51282375254/in/dateposted-public/" title="IMG_0187"><img src="https://live.staticflickr.com/65535/51282375254_2685473ae2_z.jpg" width="640" height="480" alt="IMG_0187"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

<a data-flickr-embed="true" href="https://www.flickr.com/photos/63764171@N07/51282536925/in/dateposted-public/" title="IMG_4549"><img src="https://live.staticflickr.com/65535/51282536925_616ab48dcc_z.jpg" width="640" height="480" alt="IMG_4549"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

<a data-flickr-embed="true" href="https://www.flickr.com/photos/63764171@N07/51281692778/in/dateposted-public/" title="IMG_4512"><img src="https://live.staticflickr.com/65535/51281692778_967c78fbc3_z.jpg" width="640" height="480" alt="IMG_4512"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

<a data-flickr-embed="true" href="https://www.flickr.com/photos/63764171@N07/51280777062/in/dateposted-public/" title="IMG_0177"><img src="https://live.staticflickr.com/65535/51280777062_3a7a2a7395_z.jpg" width="640" height="480" alt="IMG_0177"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

 

[OSRC]

Love it! Can't go wrong with a Tonka build..