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Hunter,
Choosing a vehicle is what do you want to drive. Not what is available. Drive what you like.

Costs of the vehicle will play a part in your total budget. Plan for it.

Pete :)
This is a really good piece of 'starting out' advice.

Some people don't really care what they drive so long as it meets their requirements and so any rust free box will do.
But if you do care then you are going to put a lot of cash or sweat equity into your vehicle and it is no good if you don't like it and lose interest. I didn't like the MR2 enough to spend on it but I am now building from scratch and will love it like my own child. Money and cost is much less of an issue and I am in it for the longer term now.
 

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So a Throttle potentiometers tells the controller how much electricity to pass to the motor or tells the driver how much is being passed?
This is why you need to read more.

We could 'spoon feed you' or you can read and find out some stuff.

Simply put, the throttle pot is the device that converts the movement of your 'throttle' pedal into a signal that the controller can use to drive the motor at the speed that you want.

Choose any build thread and start reading, read, read, read, and then when you come up with some terms that you don't understand ask for clarification.
This one by jackbauer is a good start but any would do.
 

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Discussion Starter · #23 ·
Oh so its called a throttle pot! I was thinking of rigging something like a dimmer switch used for lights to a pedal or a pedal is the on/off switch then to dimmer switch then to controller. Thank You
 

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It is very similar in action but different in construction and use.

It is very literally a variable resistance, a potentiometer, that varies between 5kohms and 0ohms for most controllers.
It differs from a dimmer switch in that there is nothing else to it in the pedal whereas the dimmer has a whole load of electronics. This is because the dimmer switch only needs to control an ac current with only 500W at the end of it. The throttle pot needs to control the controller which will have many, many DC kW at the end of it.

Also the dimmer switch will turn through 270deg of rotation and the pedal only turns through maybe 10-15deg of rotation and has to do it many tens of thousands of times in its life with out fail.

Right, enough now, go read.
Also maybe buy a book like Bob Brant's Build Your Own Electric Vehicle.
 

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Discussion Starter · #25 · (Edited)
Reading up on everything that was mentioned. One thing that bothers me is the brakes? If im going to build a go-cart, trike, or convert and old car...how do i brake?

And i need something like an amp and volt meter to know when my batteries are about to die. What do people commonly use?
Oh and DC to DC converter? Should i use one? Seems like using 2 batteries for the charge of 4 is a good idea.
 

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Discussion Starter · #27 · (Edited)
All cars have brakes. Doh!

How do you brake? Push the brake pedal. Doh!
But if i build a trike from scratch ima need to come up with some sort of braking system. Well i read about DC-to-DC converters, and if my understanding is correct they are like step up transformers, you put in a ceratin voltage and you get out a certain higher voltage. Is this correct?


heres one i found from 12v dc to 300v dc
http://www.bhphotovideo.com/c/product/181785-REG/PAG_9774_Car_Converter.html
 

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Reading up on everything that was mentioned. One thing that bothers me is the brakes? If im going to build a go-cart, trike, or convert and old car...how do i brake?
Ummm, I'll take it that you are not kidding.:confused:
You would brake each of those in exactly the same way as any other similar vehicle would brake. The only difference is that in a heavier vehicle you would use an electric vacuum pump for the servo assist as jackbauer demonstrates in his thread.
Otherwise would I be right in assuming that you have little knowledge about how vehicles work.

And i need something like an amp and volt meter to know when my batteries are about to die. What do people commonly use?
Lets cover that when we get to it.

Oh and DC to DC converter? Should i use one?
Should you use one on a go-cart? No.
On a road going vehicle it may well be a necessity depending on range.
Again, lets cross that bridge when you get to it.

Seems like using 2 batteries for the charge of 4 is a good idea.
:confused:
 

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But if i build a trike from scratch ima need to come up with some sort of braking system. Well i read about DC-to-DC converters, and if my understanding is correct they are like step up transformers, you put in a ceratin voltage and you get out a certain higher voltage. Is this correct?


heres one i found from 12v dc to 300v dc
http://www.bhphotovideo.com/c/product/181785-REG/PAG_9774_Car_Converter.html
Whatever you build you will need brakes.
If you need to ask the 'how' then I would strongly recommend that you don't build a road going vehicle, stick to a fun kart for a bit of off road play and then convert a full size and complete vehicle later.

The DC-DC is usually used, in EV context, for changing the high voltage, 144V pack, down to 12V for the lighting, wipers and other car based requirements.

If you were to convert from 12V to 300V then you would have very little current. Those converters are usually used to convert your 12v ICE car voltage to something that you can plug your your laptop charger in to, or if you get a big one you may be able to run some power tools for site work.

However, the power, less losses, is the same in as you get out.
12V at 100A in gives you less then 120V at 10A out.
 

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Discussion Starter · #30 ·
Otherwise would I be right in assuming that you have little knowledge about how vehicles work.
Bingo! I'm going to take mechanics next year in school but i have minimal knowledge of how they work. My main interests are computers. Mechanics, engineering, physics, and electronics are just a HUGE hobby of mine (I like building things and working with my hands). Like a second major i guess, and my first would be computers, but Im still in high schools so no college yet.
 

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Bingo! I'm going to take mechanics next year in school but i have minimal knowledge of how they work. My main interests are computers. Mechanics, engineering, physics, and electronics are just a HUGE hobby of mine (I like building things and working with my hands). Like a second major i guess, and my first would be computers, but Im still in high schools so no college yet.
OK, I can go with that.

However, do realise your limitations as to what you can and will achieve with what little knowledge you have at this stage.

If you have a little cash then look at getting an old invalid scooter or electric wheel chair and play with the bits in a soap box kart style, just so you get a feel for the making side.

Maybe you could use the scooter parts to make up a simple electric pedal bike to get you to school and to shops. Check your local legislation on what is allowed in your area.

What you should be doing now is looking to make a big version of the RC cars that you might have been playing with 5 years ago but without the RC bit and with you sitting in the driving seat.
 

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Discussion Starter · #32 ·
"no no brakes"....wow. see i don't want that, i want to have brakes and not have to screech to stop. :)
it cost the guy $1500 to make the go-cart...that seems a little extreme for a go-cart. i did fine this monster scooter parts website though! So might just get one of those motors. will ask before i buy it though.
 

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Discussion Starter · #33 · (Edited)
If im going to build a go-cart to start off, should i go with 18, 24, 36, or 48 volt motor? They do have motor kits with motor, throttle, and controller! Would any of these be decent for a street trike?

oh and is 3 amp hour any good? How many amps or amp hours should i be looking for?
 

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You definately want brakes.:D

The other option is to find an old ride on lawn mower with a dead engine.
Whip the engine out and replace with a small motor and pulley straight onto the belt drive. Add two to four batteries and a cheap controller and you have an (almost) instant EV. You can probably go to your local junk yard and buy some good used Optima 12v batteries for not too much money. It would come complete with seats, brakes, wheels, steering, etc.;)

In this case a PM motor would be better as it won't over speed like a series motor would.
Many mobility scooters have PM motors anyway so it would be a good parts donor.
 

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Get a few electrical text books out and read up on electrical power (Volts, Amps, Watts) and then think about what terms Amp hours and Watt hours mean.

Consider that there are 746Watts in 1hp.
Volts x Amps = Watts
Watts is power by the way.

OK, enough free schooling now, it is midnight here and I need to sleep soon.
Also I expect the students I teach to do a lot of their own study and research and I will expect the same of you.

Treat the above as home work.;)
 

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Discussion Starter · #36 ·
So if i read correctly, 3 amp hours is an hour of work producing 3 amps. So if i draw 3 amps from the battery it will only last 1 hour before it is dead and i have to recharge. correct?

and a 24 volt motor at 21(rounded) amps would output 500 watts of power? which is the same as 1.5 hp?

Let me know if i did my homework right? :)
 

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So if i read correctly, 3 amp hours is an hour of work producing 3 amps. So if i draw 3 amps from the battery it will only last 1 hour before it is dead and i have to recharge. correct?
Yes, that is right but in reality you wouldn't want to use all of the capacity in a battery as it will drastically shorten its life. For lead acid you would keep within 50% and for LiFeP04 80% of capacity.

Consider that there are 746Watts in 1hp.
and a 24 volt motor at 21(rounded) amps would output 500 watts of power? which is the same as 1.5 hp?

Let me know if i did my homework right? :)
Hmmm, interesting arithmatic, you may want to submit a proof and then make a fortune selling the process.;)
:D


I'm definately off to bed now.
Do more homework and lots more reading.
 
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Got to school and get your degree in physics and get a damn good job and buy one already done. No need to muck around with stuff you know nothing about. Go Carts are cool but they need brakes too. You can buy the stuff you need. I'd not build those. Just buy them and install them according to your build. What you want is no easy task even with a go kart but it would be on a much smaller scale and with lower voltages too. Much cheaper to by your components. I'd suggest if you want to do a cart is go find a good racing style cart with no motor used on CL and go from there. Not worth the trouble to build one unless you have full access to a shop that can handle bending, jigging, welding and engineering that you'd need to do. I am sure your not in that zone yet. You can put together a nice cart if you piece it out and then assemble. A home built puzzle so to speak.

DC DC is a step down. I am going from 112 to 13.6 volts.

Pete :)
 

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Discussion Starter · #39 ·
Ima get a degree in computer information systems/technology. The reason i don't want to buy one is cause i like to build things. Heres what i found at a website:

Battery charger $45 - http://www.monsterscooterparts.com/12voltcharger4.html

Motor kit $100 - http://www.monsterscooterparts.com/24-volt-500-watt-motor-controller-throttle-kit.html

Battery $70 - http://www.monsterscooterparts.com/24vo12amphob.html

DC amp meter $30 - http://www.monsterscooterparts.com/dc-ammeter-0-5-amp-range.html

DC volt meter $30 - http://www.monsterscooterparts.com/dc-volt-meter-0-50-vdc-range.html

On/off Switch $6 - http://www.monsterscooterparts.com/...-mini-chopper-ground-force-pocket-rocket.html

pedal $20 - http://www.monsterscooterparts.com/minimoto-go-kart-accelerator-pedal.html

What I'm missing:

Brakes
4x Wheels
Transmission gear
Transmission chain
Steering wheel
Rear wheel Axle
Front wheel axle
Chassis
Seat
Control Panel


I need to learn how a steering wheel works, so if you got anything on that, such as a website, please let me know.
 

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Discussion Starter · #40 ·
So if my revisions are correct,
500 watts = 0.670511045 hp
900 watts = 1.206919881 hp
1000 watts = 1.34102209 hp


And i want some high horsepower so for
5 hp = 3728.499357911 watts
6 hp = 4474.199229494 watts

So it seems like i need to find a 5000 watt DC motor...AHH!
Would 1000 watts of output be sufficient?
 
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