6x2 Quad Front Steering car - 1/28 RC car

Hello!

This is the mini six-wheeler RC car inspired by the Tyrrell P34, featuring four front steering wheels. The size roughly matches 1/28 Kyosho Mini-Z series rc. As a six wheeler, this car performs well on lightly dusty surfaces such as wooden floors, garages, concrete, and asphalt. However, it’s not quite suitable for RCP tracks—its four steering wheels generate excessive front-end grip, and the short front treads make traction roll more likely.

one more thing, print the body vertically for the optimal result.

Building Tutorial:

Part List:

TDLR:

if you’re building from scratch, buy everything between equal sign lines.

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Amazon shopping list , including batteries, motor, bearings, servo, screws and nuts, pinion gear, ball diff, and springs.

Parts from Aliexpress: [brass tubes], [esc], [dumbo rc transmitter with micro receiver]

These brass tubes are 5mm long and 3mm in OD, for the front suspension.

[If brass tubes out of stock]:just get 16mm long m2 shoulder screws. Enlarge the M2 screw holes on the front suspension part of the chassis to 3mm to fit them in.

Rims and Tires from Hobbytown: [
8.5mm rim], [14mm rim], [8.5mm tire], [14mm tire],  but notice that this particular 14mm tire isn't good on wooden floor. Reflex racing is best for wooden floor/tiles, Marka is balanced on everything, and DS racing is more suitable for rough surfaces.

Tools:

• screw drivers

• solder iron(soldering motor to esc)

• a small drill(~ 1.8 to 2 mm Dia.)

• utility cutting plier(not platic cutting pliers! It's for cutting metal springs)

• charger for batteries

Beware, there are two types of Ph2.0 3pin connectors, one comes with two rails on top(like those on your typical 2s batteries), and one comes with single rail. The esc+battery combo I've provided is the single rail type.

Finally, all the 3D printed Parts of course.

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Part List Breakdown:

Screws:

just buy this set for simplicity, comes with MOST screws needed, plus it comes with an alan key.

alternatively, you’ll need:

• [m2x16mm counter sunk screw] x4——————for front suspension

• [m2x8mm counter sunk screw] x4——————-for side body mount

• [m2x8mm whatever screw] x2————————-for front body mount

• [m2x(6 ~ 8)mm counter sunk screw] x4———-for front steering hub

• [m2x20mm counter sunk screw] x4——————-for front wheels

• [m2x4mm counter sunk screw] x2(or3)————-for front bumper, cuz there’re three screw holes

• [m2x4mm counter sunk screw] x2———————-for front panel

• [m2x(8 ~ 12)mm whatever screw] x2——————-for motor mount

• [m2x(4 ~ 6)mm whatever screw] x2——————-for motor mount cap

• [m2x(4 ~ 8)mm counter sunk screw] x4————-for rear strut tower

• [m2x(4 ~ 6)mm whatever screw] x3——————-for upper shell

• [m2 whatever just dont too crazy long] x2———-for mounting servo

• And here’s the screws you need that doesn’t comes within the kit:

• [m2 x 40mm screw] x1——————————————for steering arm

Springs:

it’s going to be wasteful but just buy a box of these…

but if you really have to only get what is needed:


• [0.3x4x7] spring x 4———————for front suspension, 0.3 is wire diameter, 4 is coil diameter, 7 is length. If you can’t get exactly, stick with 4 for outer diameter, look for shorter length or smaller wire diameter. Get the front springs as soft as possible because you have 4 of them anyway.

• [0.5x6x10] spring x1-——————-for rear suspension, but you should test more than one rear spring at 10-15mm with different coil diameters to see what works best for you. If too stiff you lose traction when accelerating, if too loose you’ll get under-steering.

Mini-Z related parts:

• 1x mr03 diff, like this one, or anything that you got pinion for. If you do get this one, keep reading and you’ll know what pinion gear to get.

• 8x mr03 locknuts(m2 locknuts. 6 for the wheels, 2 for the motor mount.

• 4x mr03 8.5mm(for front wheels, ideally +0 or -1 offset, +1 at most) rims and tires.

• 2x mr03 11 or 14mm rims and tires

Rims I used in demonstration video is this, but it's always better to go for proper wheels, such as these 8.5mm rim, 14mm rim, 8.5mm tire, and 14mm tire.

If you don’t have rims at correct offset, just mount them reversely

Electronics

This is where you can, or actually, should improvise, but I’ll leave my setup as a reference. The only important thing is to make sure you stick with one type of connectors(mini ones or standard ones) on all electronics, depending on your receiver type.

Servos:

• servos should be at the size for open class 1/28 rc, like this one

ESC options:

• ESC, I recommend this one. It comes with standard servo connectors. Very smooth.

• This ESC is alright, weaker but comes with small connector.

Motor options:

• Mini z motors Definitely works. Any 130 brushed motors shaped like that should fit in, except for those that got spray paints on the outer shell, which slightly thickened the shell.

• I used tamiya mini4wd motor. Works perfectly, and need a little soldering work.

Battery options:

• Largest battery that can fit is this one.

• Most open class batteries will fit just as well and work better.

• I believe those blue batteries for Wltoys K989 will fit in no problem.

Bearings

essentially standard mr03 bearings but need an extra pair of front sets:

• [2x6x2.5] bearing x9, 8 for front wheels, one for rear diff.

• [3x6x2.5] bearing x3, all goes into the rear diff.

Other items

There’re also a few parts from tamiya mini4wd being used here:

• Mini4wd Pinion Gear, if you went with kyosho miniz ball diff that we mentioned earlier.

While UNECESSARY, but it’s helpful to have 4 of these:

• eyelets for steering hub

They are originally copper eyelets for tamiya mini4wd stock bushing, but I use them on the turning hub. Slightly improving suspension travel.

Lastly and most importantly, you need this brass tube, 12 tubes per car:

• brass tube 

this is basically a cheaper version of brass tube used for mini4wd double layer roller, like the one shown below. They are expensive because they are tamiya, and there’s no point getting the original part as we’re not even using it on mini4wd. We will use them to form the front suspension and steering system.

You'll also need a controller, and you can either get something as cheap as this one, or go all the way up to a Luxrious Noble NB4. This is your choice.

And if you actually made it to here, allow me to say thank you: thank you for showing interest, and for choosing to build or even improve this project. The focus and patience you've demonstrated are rare virtues, and I hope you continue to carry this passion and mindset into everything you pursue in the future!