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What ?
Electric go kart for kids which looks like retro cars from 20th. Made mainly from wood (no need for metalworks talents) and with ordinary tools like saw, drill etc.

I encourage to watch the video attached to this instructable to see how electric car look and how it drives.

Why ?

Oh, there are plenty reasons why to build a car for kids. Ask kids, especially boys and they will tell You why ;-)

What will be needed ?

- wood (pine)
- bicycle wheels
- electric engine with controller (more about it later)
- 12 batteries
- two long construction screws
- some tools but mainly saw, drill
- strong glue for wood (polyurethane would be the best)
- nails and screws

Step 1: Project Plans and Design - Boring Part ;-)

Project plan
It's important thing to know what are You going to build ;-) Don't ignore this step. Search for inspirations in the internet. Do Your research using the keywords like: go kart, kids car, cycle kart etc. When You will have in Your mind what exactly You want to build then measure Your child. Not only height, legs length but also wight. It is important property cause we are building an electric car and we have to estimate the total car+driver weight to buy proper batteries and engine.

Body/chassis design

OK, so If You have all measurements try to draw the car body shape taking in consideration following things: - how long are kids legs - this will determine the length of the mask/hood - how long are the kids hands - this will determine how high should be the steering wheel to provide comfortable grip and to avoid kicking it with the knees - what is the weight of the kid - this will determine such things like engine power, but also how strong should be the car's frame. Less weight and dimensions -> less wood for frame -> less total weight->longer driving time.

Electronic and mechanics design

The last part of Your design is to decide what engine and batteries You have to buy and how the power would be transmitted to the wheels. All of that is too complicated to describe, so I will just show You how I decided about my project.

So, I chose the 350W engine with brushes and with built in gears/transmission which reduces the RPM to 600. Why such engine ? Power - 350W is just enough to get the go kart running with top speed up to 25 km/h. Moreover, bigger power consumes bigger energy. Voltage 24V - I wanted to have 2 * 12V batteries to make my car better balanced. Batteries in front, engine in the rear part of the car. Brushes - engines with brushes are a lot of cheaper than brush-less ones. Built in RPM reduction - standard engine gives more than 2500RPM this is waaaay to much. Reduction also provides more power at slower speeds

Step 2: The Frame

First of all - You don't have to build the frame from the metal. I choose the pine wood for the frame (because it is light and flexible enough to suppress the vibrations) and the oak wood for the suspension (because it is hard and durable).
During building the frame You have to remember that only gluing or just screwing the wood isn't enough. So mix this both techniques. Nails are of course pretty bad idea ;-)

Step 3: Chassis / Car Body

The body could be made from thin plywood. It is light and easy to work with. In my project I've build some parts from plywood (the hood and the rear), but the 'door' sides I've made from 2" desks. It is because those elements will have to support the weight of the child during entering to the car.

Step 4: Painting

If You have spray gun - use it, You will have very smooth surface. If You don't have such device I recommend to use paint roller instead of brush. Roller gives smoother surface.
To get the smoothest as possible surface use the undercoat paint. If You skip this step You won't be able to cover all wood pores and the surface won't be flat. I recommend also to dilute the paint. It will give thinner coats and dry faster. This will give You more control to produce fine, flat coats.

One more thing. If You find the holes, even the smallest ones, use the spatula to cover them. If You don't do that, they will be visible after painting.

Step 5: Axles, Suspension and Wheels

Front axle
Front suspension is the trickiest part of whole project. It's hard to get parts which would work with standard bicycle wheels in the shops, You probably would have to make those parts yourself.

I've created the front suspension parts from oak and bicycle headstes (because I don't have any experience with metalworks). They are working perfectly fine even when my child is driving off road. I saw however that some people are making front suspension from ordinary pipes - i didn't try that.

Rear axle

I decided to make only one wheel powered by engine. Why ? To avoid need of differential and rigid axle. Now I know that rigid axle would be better when driving offroad, but during the build i decided not to make it because of the friction during turnings. Such friction would consume more power and drain batteries faster.

So the right wheel is attached to the heavy construction screw (with the highest strength atests) and the left wheel is spinning freely on the bicycle support.

Power is transmitted through the motorcycle chain from engine to the wheel using 'freewheel'. It's important part to avoid back current generations in the engine and avoid broken engine controller.

Step 6: Engine, Power and Electronics

As I wrote in the design section, I've used 350W electric engine. Such engine needs 24V and consumes up to 28A. It is quite a lot, so I need the really thick wires to support such current. It is the formula which You can use to determine the wire thickness considering the current, voltage and the wire length. You have to remember, that wires and DC current will generate the voltage loss. Losses depends on wire length and diameter - shorter, wider wire will produce less voltage loss.
If You don't want to play with formulas, just use the power wires from ordinary car.

To power the engine I've used two 12V (18Ah) batteries which each one weights almost 4,5kg (simmilar to those from cars). Such batteries are the cheapest but not the best for electric engines. Batteries and engines are the really wide topics, so I won't write about it more - search in the internet about this if You are curious about the best solutions. My batteries gives my son several hours of fun, so they are enough.

To control the engine You need also two more parts - the hallotron (gas pedal) and the electronic controller. Those parts could be easly bought in the shops. I've used the parts from some Chinese scooter. One thing to remember - controller must be capable to handle the engine power (and current).

Step 7: Finishing and Detailing

Finishing is so individual process that I won't write much about it. Use Your imagination. I've added to my go kart - upholstery, lights, fake radiator and of course the black horse statue on the hood :)

So that's all :)

If You are interested in this project, watch my video which is step by step tutorial on how to build electric car for kids.

Any questions ? I will answer all of them ;)

<p>My father built me and my sister something similar when we were kids. his was a replica of the 1903 curved dash oldsmobile, and was powered by an model T ford alternator, powered by a single 12 volt car battery. was a great toy, didn't go fast but went in style big time. was a regular feature in the local sata parades and vintage car meets, and was my pride and joy. sadly im yet to have kids, but when i do they will be spoiled rotten with many similar toys as im a real jack of all trades. currently working on a couple of instructibles and this has given me a target to aim for. Awesome work mate!</p>
<p>Oh, what a great dad You have. Curved dash isn't so easy to make.</p>
<p>That is a very nice project. And I can see he really likes his car. But then what kid wouldn't, or even an adult for that mater. Now I see upgrades for suspension coming to dampen the rough off road driving. You could even lighten it up some going fiberglass and polyester resin with the design. Lighter means longer battery life. Bravo sir Bravo!</p>
<p>thanks :)</p>
<p>Thanks. Yes You are right. Next step will be definitely rigid rear axle and the suspension.</p>
<p>Could you please tell me where you got the engine and how much it cost you?</p>
<p>No problem.</p><p>Engine + controller + gear = 75 USD<br>hallotron (gas pedal from scooter) and ignition - 10 USD<br>freewheel + chain = 13 USD<br><br>I've bought everything in some local (Poland) distributor which is distributor of chineese.</p><p>You can also search fur this things on eBay</p>
<p>Thank you so much</p>
<p>Beautiful</p>
<p>Excellent work, well executed. I like this.. A LOT</p>
<p>Great design and great idea. It has my vote . Just a few thoughts I feel that it isn't up to the person doing the instructable to have to go into every tiny little detail of the project, obviously the more info the better but if your really wanting to build something like this then you should do some more research for yourself. With the ease of the internet and the fact that the end user of the project will be different for everyone, I feel that it is up to the individual builder to make it to the style and standard of what they want it to be. It's like safety warnings if your not smart enough to work out that power tools are dangerous then you shouldn't be using them. Same as this project if your not smart enough to build one for yourself and use it safely then don't do it. If your putting your kids in something you build and it falls apart then its your fault not anyone else's. You can't blame another person for something you built not being safe enough. </p>
<p>My Dad who would be 98 this year had one just like it in his youth - here's a picture of him in it....</p>
<p>So I recently picked up a massive electric motor that cranks out 3500 rpm at 11/16 horsepower. The problem is that it runs on 120 volts AC. I could wire up an inverter to convert DC battery power into AC, but I'm not sure if this motor could even power a go-kart in the first place. </p>
<p>Hm... in my opinion even if You would lower and convert the voltage to 12,24,36V DC this engine could not be good for an alectric car. 3500 RPMs are a lot. You would have to lower this value too. It can be done using some gears (like in bicycle) or by steering the engine with lower currents, but in such case, the power also would be lower.</p><p>Hm.. maybe a better idea is to buy a ready to use electric engine kit ? It's not so expensive.</p>
<p>Thanks, I wasn't sure. I'll probably use this motor for a different project then.</p>
<p>This is an impressive and nice project! It reminds me of the &quot;go kart&quot; projects found in old &quot;popular mechanix&quot;-style magazines from the past. Kudos to you for carrying on this tradition, and sharing it with us!</p><p>I did see a few areas which could use some improvement for safety. This is important information. As I am going to be a bit long in the details, I'm going to break this up into a series of posts:</p><p>1. Electrical wiring (sizing for current, and proper connection techniques)</p><p>2. The steering linkage</p><p>3. Safety padding</p><p>I will also discuss some alternatives around using a differential vs. solid axle vs. single drive wheel.</p><p>I am not an expert on these subjects. I draw upon my experience with hobbyist robotics, and my experience helping a friend of mine construct, repair and maintain electric wheelchairs and mobility scooters. I have seen and experienced what can happen when things go wrong: Ccreating an impromptu electric welder is not out of the realm of possibility here!</p><p>I'm not trying to usurp your efforts here. I instead want to expand on them for others, to help them make the best of this great project as their abilities will allow. My advice is given to you and others in the hope of making this and other projects like it as safe as possible, especially where children are concerned.</p>
<p>My thoughts exactly regarding the old Popular Mechanix magazine articles.</p><p>Very nicely done project!</p>
<p>Sizing Electrical Wiring</p><p>You indicated that you need to size the wiring properly. But you didn't give much information there on how to do so. The best way is to find an online &quot;wire gauge to current&quot; chart; there are also online calculators for this as well. </p><p>Sometimes you will find charts that list the gauge for &quot;chassis wiring&quot; vs &quot;power transmission&quot;. This can be confusing. Instead, know that the kind of wiring for virtually all projects is considered &quot;chassis wiring&quot;. Ignore the &quot;power transmission&quot; part.</p><p>Most of these charts use a resistance calculation for copper. Copper wire has a low resistance per foot depending on its diameter, or gauge; some wire is actually aluminum, and copper plated. Aluminum has a higher resistance than copper. If this is the case with your wire, this needs to be taken into account in the calculations. The calculations for copper will lead to a smaller gauge of wire than those for aluminum. So if you know that your wire is really aluminum, use the next higher amperage value on your chart. Or better, find a chart or calculation for aluminum.</p><p>For most projects involving electricity, you only really need to be concerned with amperage, total wire run length, and voltage drop. Here's an example of such a chart (there are many online): </p><p>http://digitalcartography.com/n0eq/astro/WireGauge-Current.jpg</p><p>On this chart, you'll see at the top how many amps you want the wire to support. On the left is a sidebar with two columns for voltage drop. A 10% voltage drop means that the device being powered will see 10% less voltage than what is being provided by the battery, for that gauge and length of wire. </p><p>Let's say (for this project) we want to have the lowest voltage drop. The circuit that we want to make, from the battery to the switches/pedal, then to the motor, then from the motor back to the battery is about 15 feet long (you'll want to actually measure this as you build it).</p><p>You mention that the motor consumes 28 amps at 24 volts and 350 watts. You didn't mention if this was the stall current, or running current. This is very important from a safety standpoint, because if you don't size the wiring properly, then the wires could heat up to the point where they melt and catch on fire. Understanding the proper way to determine the wire size will make for a safer project overall.</p><p>The Ohm's Law calculation for DC current (P = I * V, therefore I = P / V) says that the motor would only consume ~14.6 amps. I'll give you the benefit of the doubt and say that you doubled this measurement to account for the stall current. Knowing the stall current of the motor is important for sizing because you want to size the current handling capacity of the circuit for the maximum capacity. A motor at a dead stop with no load is considered (electrically) to be stalled when voltage is applied (only for a brief instant). That is the current level we need to work with.</p><p>Measuring this current of a brushed DC motor isn't difficult: Use a multimeter to measure the resistance across the terminals of the motor, then plug that value into Ohm's Law (V = I * R) for the voltage being used.</p><p>Your current measurement was 28 amps. If you look at the chart, you'll see along the top a number of current readings. Find the one that is for 28 amps...hmm, there isn't one? Ok, use the closest one that is higher or larger. In this case, the column for 30 amps seems best. This is done as a &quot;safety factor&quot;, as sizing for more current is never a bad thing. So look down that column until you find 15 feet in the 3% voltage drop column on the left. You'll see that it lands on a box that says &quot;8 AWG&quot; (gauge 8 wire - AWG = American Wire Gauge; in other countries wire gauges are likely to be measured differently. If so, you'll need to find an appropriate chart or calculator, or do a conversion from AWG to your standard).</p><p>So now we know that we need 8 AWG wire to handle the current of 28 amps at 24 volts for this 350 watt motor. Simple enough, right? So where do we go from here? Well, we need to wire things up, and we need to do so properly...</p>
<p>Proper Splicing and Connection Techniques</p><p>I noticed in your project, you seem to have twisted the wires together, perhaps using wire nuts or some other method. You then taped it up with duct tape. I didn't see any fuse(s) used or mentioned. Nor did I see any form of routing the wires and ensuring that they were adequately aranged and mounted. All of these are issues which can lead to failures down the road, the most serious of which could become a direct short across the battery, leading to a potential fire.</p><p>When assembling an electrical system like this, a few simple techniques can be utilized to keep the system safe and reliable in the future. An understanding of automobile electrical wiring, as well as other large appliance chassis wiring, can be helpful to understand the techniques.</p><p>First and foremost is use of fuses to control the flow of current in the instance of an overload or short in the electrical system. These devices work to help prevent fire in the wiring should a short or overload occur. Equivalent value circuit breakers for DC current could also be used.</p><p>You'll first want to install a main fuse. This fuse should be sized for the total current the system is supposed to handle. It must be located as close to the battery as possible, near the positive terminal of the battery. Mounting it inline, not more than a few inches from the terminal, helps prevent the possibility of a short occuring before the fuse. It won't stop you from dropping a wrench across the terminals. If that is a concern, then the battery should be mounted inside a box, or some kind of shield over the terminals should be fabricated.</p><p>After this fuse, the wire should be routed to a secondary &quot;fuse box&quot;. This will distribute the current to the various circuits of the project (motor, headlights, horn, radio, etc) via secondary fuses. Fuse boxes for multiple circuits can be found online or at an automotive supply store. For this project, you'll probably only want fuses for the motor (30 amp), and for a few accessories (5 amps). Note that you'll want to size the wires again for each circuit, and for the main connection from the fuse box to the battery (since this will be a shorter run, the wire can be smaller).</p><p>The wires should be routed and mounted neatly to the body. This way they won't move, and they will be out of the way and not touching any moving part of the project (which could wear thru the insulation). For extra protection, the wires could be placed inside a split-loom tubing or spiral wrap. These offer addition abrasion protection and support, plus they can neaten the appearance of the wiring. They probably aren't needed for this project, but use them if you feel like it.</p><p>You might want to install a main &quot;bus bar&quot; for the negative side of things. On and automobile, this is provided by the frame or body of the car. For this project, a metal bar that runs from the front of the vehicle to the rear can be used instead. A copper bar would be best, but aluminum or steel could be used as well. This bar will provide a common point to connect the &quot;return&quot; wires to, instead of having individual wire runs. The fewer and shorter the wires you run, the less that can go wrong. To make a copper bar, take a piece of copper pipe or tubing, and flatten it along the length. Drill holes for bolts or screws to mount it to the frame. Connect the wires to the bolts/screws.</p>
<p>Steering Linkage</p><p>In the pictures, it looks like you are using rope or something of that nature to connect the wheels to the linkage on the steering column. Should this rope break while the vehicle is being used, the car will lose steering, and it will crash. The rope could break due to age, abrasion, or environmental conditions (or some combination). Instead, this should be replaced with metal rods bent to fit. Don't be tempted to replace it with steel cable. It will still wear and fray, and over time it too can fail.</p><p>Safety Padding</p><p>25 kph (~15mph) is still a pretty good speed, so limiting injury in the event of an accident should be in the mind of the builder for their children. Adding padding material to the edges of the seat area, and the interior of the vehicle can help limit injuries should an accident occur. It's one reason some old automobiles had tufted fabric and leather interiors.</p><p>Rear Wheel Drive Options</p><p>The choice to use a single rear wheel drive mechanism is actually sound and practical. Many standard go karts use the same setup. It's reliable and simple to construct, and for most uses it provides adequate traction. But if the builder wants a more robust drive mechanism, at the cost of complexity and maintenance, there are a few options which aren't too expensive to implement.</p><p>Actual full differentials can be found (relatively) cheaply on the used market. Look for ones meant for quad cycles. If you need something smaller, many electric mobility scooters (not wheelchair!) use what's called a &quot;transaxle&quot; that combines a motor, gearbox, and differential all in one package. The motors usually run on 12 or 24 volts (24 volts is most common). Sometimes you can find them as used components online or through other sources. Or find an old used mobility scooter and remove the parts. Because they are designed for moving adults around, they are built very strong and can take a bit of abuse for a project like this one.</p><p>A solid drive axle will work fine as long as driving is done on dirt only; the dirt will give some slip to the system to prevent &quot;wind-up&quot; and breaking of the axle. You could also design and fabricate a &quot;limited slip&quot; solid axle. Essentially this is a two-part axle coupled in the middle by two &quot;clutches&quot;, which are composed of friction material pressed against a middle drive pulley, which is driven by the motor. In normal forward motion, the power from the motor is transmitted to both rear wheels fairly evenly, but in turns one side or the other is allowed to &quot;slip&quot; by the clutch, preventing wind-up.</p><p>You can also take a cue from the makers of one of the more popular types of children's ride-on toys: Use two electric motors, one for each wheel. This also gives you the ability to incorporate a speed control (high and low speed). This works by using a pair of switches (you could also use relays) to wire the motors in series or parallel. Do some research on the subject, and you will find plenty of information on how this system works. Basically it acts in the manner of an &quot;electrical differential&quot; when turning.</p>
<p>Final Thoughts</p><p>Aren't you glad I spread this out! I knew it was going to be more than a simple post could handle. I hope it does help others. In closing, I want to let you and others know to take to heart what you said at the beginning of the project: To do research and study what was done in the past, both on real automobiles (in both design, mechanics, and electrical) and on chidren's ride-on toys.</p><p>As I noted at the beginning, there are articles in old &quot;popular mechanix&quot; type publications in the past (google 'em) that can help you with your design and fabrication. Also research how old automobiles from the turn of the 20th century were designed and built (including and especially electric vehicles - yes, the electric car idea is very old!). You'll notice a very wide range of things were done by various manufacturers, all of which can give you ideas (both of what to do, and what -not- to do!). </p><p>You can find these articles in old book and magazines, thru resources like the Internet Archive and Google Books. You can also find them at used bookstores occasionally, if you want something physical to read and study.</p><p>Above all, try to keep safety in mind, and only implement features and designs which will be safe, or can be adapted to be safe, while also being mechanically and electrically sound. </p>
<p>sweet build, lucky kid!!</p>
<p>I luv it, luv it, luv it! I'm not a kid but would certainly love driving this myself! My gr-grandson would, too! It's nice to see there are still Dad's out there who want to do something special for their kids rather than just buying the Toys R Us type cars! Great job! Your son (or daughter) will never forget this! And yes, girls would love one, too! </p>
<p>Wow good for you Dad. These are things a kid will cherish for the rest of their lives.</p>
<p>Took one look at the thumbnail on the main page and thought awesome!</p>
<p>how much time does it take to build in total (rough estimate). I think this is so cool and would love to build one with my son, but would like to know what type of time I'm committing to.</p>
<p>Oh.. Take in consideration that I was preparing the wood by myself from raw material If You buy prepared, sanded wood it will be a lot faster.</p><p>It takes me almost month working about 8-10 hours weekly so it gives about 40 hours of continous work</p>
<p>You have left out much essential detail that people might want to copy your project:</p><p>How have you made the king pins (steering)</p><p>How does the steering work</p><p>How did you connect up the motor electrically</p><p>How do the brakes work.</p><p>How much does the car weigh without the driver and battery pack.</p><p>they may be in the video (which I haven't watched yet) but it is useful to discuss them as they are difficult areas to manufacture.</p><p><a href="https://www.instructables.com/id/Building-an-electric-racing-car/">https://www.instructables.com/id/Building-an-elect...</a></p><p><a href="http://www.thenorwoodhome.com/2008/09/building-an-mg-tc-pedal-car-introduction/">http://www.thenorwoodhome.com/2008/09/building-an-...</a></p>
<p>You are right. I will complete this informations when I will have a minute</p>
<p>Great end result, fantastic work</p>
<p>That's awesome! Do you have an adult version :P?</p>
<p>:)</p><p>No, I don't have, but I will definitely built one in the future:)</p>
<p>Awesome project!</p>
<p>thanks</p>
<p>That is so cool!</p>
<p>Thank You. It takes a quite a lot of time to built.</p>

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Bio: I love to make DIY projects with my son
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