I'm going to calculate the top speed that you could get if your motors were powerful enough: 3300kv * 3S * 4v per cell = 39600 rpm when under no load. Ok so I'm going to guess your wheels are 80mm diameter. That gives your wheels a 8 * 3.14 = 25cm diameter. So every rotation we go 0.25 meters. Next: 39600 rpm / 60 = 660 rotations per second. 660 rotations per second * 0.25m = 165meters per second. That's the speed it'd go at if your motors ran at their no load rating. (in reality they run a bit slower than what I calculated but it'll be about right) 165m/s is about 596km/hr... so I think it is safe to say, it is geared just a wee, tad bit too high LOL Say you were aiming for 80km/hr max theoretical speed, then you will want a 7.5 to 1 reduction gearing on it (because 596/80 = 7.5). Now, of course, the motor won't run at its no-load speed so you're going to get a bit under 80kmhr. But that's a starting point, you can take it from there and figure out what works :-)
Your a legend mate!!!! I did this math's to and got pretty similar numbers!!!! and yeah its assuming quite a bit, the kv is not verry acurate/ rounded up in china. Now i am going to try this with brushed motors because they will start up straight away. and not need to oscillate. I'm sure it will still go fast!!!! Thanks for Watching This awesome ULTRA RC video Mate!!!!!!!! I appreciate your Epic support!!!! I was replying to this but then you tube put it in spam???? anyways all good now!
Nice calculation but it's off due to the mah of the battery and I doubt that esc can push anything with a 1:1 gear ratio you need something like a 150amp esc or higher 5000mah lipo battery and a torque 3800 kv motor
@@CORINKERSTEN there is one problem with brushed motors in general and that is that they still tend to lack a lot of torque when the motors are small in size. brushless motors often have more torque for the size, mostly because they can more easily handle larger amounts of current with simpler coils since there are no brushes(brushes can be like a sparkgab and so tend to by far be the weakest thing in a DC motor by far since they can easily melt, deform or break) brushless motors don't have that. so brushed motors tend to need a lot of speed before they get to their rated ratings. in brushless motors they also need to move fast to get to the rated ratings but they are slightly less sensitive to breaking due to high startup current. brushless motors tend to break due to just getting to hot or the bearings or such breaking, but this also means that the brushles motors can more easily handly startup current peaks. you can make it sensored yourself by attaching magnets to the wheels that is what I wanted to do. you will need to make your own ESC but a sensored ESC is easy to make(you can also buy them for quite cheap, something like 120A for less than €20, and you might want to have both motors run from the same ESC. while running them both seperate at their optimal efficiency and timings will make it more efficient, tunable and give you more power and speed. having them both run from the same ESC will allow you to save cost in some cases and size and also gives you increased efficiency if both motors are the same quality, if something goes wrong change the sensors to the other motor so the weakest motor has the sensors on it. but running 2 seperate ones should be good as long as the motors are the same quality so that they both produce similar force. if you sensor them you can basically just use a 3 way H-bridge and directly connect the sensors to that, adjust the magnet or sensor placement to get optimal timings and the motor should work perfectly always. speed regulation can be done using PWM. building a brushed version however still has it's place and certainly is interesting and a good goal, since brushed motors are a lot cheaper and do not need a ESC. so if you can use them in direct drive properly that would really be great. but perhaps it might also be worth keeping the car as light as possible. and perhaps using some kind or semi sensitive spring suspension so the contact with the floor is more constant. this normally doesn't make to much sense other than grip. but in this case it can even out the strain on the wheels. otherwise when it goes over small wobbles the wheel force might change. perhaps howeer you can also do this more easy by just using the spring effect 3d printed stuf has you don't need much just a little so it should be enough. keeping it light is also a nice optimization, for a light car the suspension effect will be more important since if it jumps up at every wobble that won't be nice. in real cars that isn't as much of a problem but rc cars are smaller and so have more extreme responses. since DC motors are cheaper(some years ago in germany they sold 500W brushed motors for less than €2 a piece) you could also make it like one of those big truck trains for moving goods, just then make it a dragracer with many motors direct driving many wheels. just add wheel motor combinations like you have now and eventually so for example a 6 wheel one with 4 wheel drive. that way you have more startup force and more general force. if you add even more wheels as you might know steering might become harder but you could make a bending frame so every 2 wheels(on opposed sides) have their own private section and then they are all connected by pivot points where they can rotate then when you want to turn you just turn al of them this won't really work well when not moving since that would require a lot more force so to test it you should test it while driving or while in the air or such. you could add a RC servo on each of those pivot points to all controll them. or you use one big servo and then use wires. the wires go through the middle over the pivot points so they don't get the rotation from previous parts eventually they go outward in a triangle from the last pivot point before their actual steering location and so when that one powerful servo rotates the entire frame of the car will bend/curve with it like a snake. that way you couldn't make to sharp turns to easily(unless you have a really powerfull motor and spend some work into designing the parts) but it will result in insane amounts of grip in turns and you will keep optimal strength. you could also allow them to move up and down somewhat that way it also keeps good ground contact with as many wheels as possible without needing to add suspension. and ofcource it would make for a interesting rc device.
I wanted to build a similar thing, however I wanted to make a super small fast rc car, as esc I was thinking about either using a broken small 4in1ESC I had laying around, 3 of the esc's in it work, one has a short cirquit so I desoldered the broken transistor but it uses parts that are really old an uncommon and it is really small so repairing that broken one would be a lot of work and it might not work so I decided to keep it for small rc cars or planes where I need 1 2 or 3 esc's. my other option was to make my own ESC, I can do that, that honnestly wouldn't be to much of a problem, only to tune it to get it working properly at full force I would need it to be sensored. so I got some magnetic switches. I want to test if I can directly out of the wheel, otherwise I might add magnets in the tires and read those to know where the motor is. I currently have 4 630kv motors, very small 1cm diameter 1cm long there where no specifications on the force and such so I will have to see how strong they are, I they are multistage so that is good for torq. they also where almost around as expensive as directly buying 4 bigger drone motors at the same time, however these ones where really small and having a super fast micro rc car is something I have wanted for a while since those things look many times faster. and due to low weight I might be able to add other cool things like remote extendable wings, boat mode, etc.(I will probably make my own rc receiver and such, I have one laying around so perhaps I use that one, but buuling it myself will allow for shaping it to the car.
I thought about using a drone four motor direct drive configuration. This is my mission );o) Would you even need a steering rack if you just altered power to each wheel?
Hi! I'm building a 1/10 dragster based off these plans as a starting point. How did you handle connecting the ESCs to the receiver? A 2-1 adapter with 1x BEC positive?
Yes lower kv would definetly help, so would smaller wheels, higher voltage maybe but also cause smoke. Sensored motors would make a difference to!!!. Thanks for watching ULTRA RC mate!!!
Awesome:) try an outrunner motor and it will have a little more torque I think. I use a outrunner in my WL144001 and it's awesome torque to break tires loose at any speed;)
@@CORINKERSTEN could try gimbal motors, they have gone of torque and work at a much lower rpm. Which means they won't spin out forever and no more push starts.
Yeah i have not made another video, Thanks for watching this one!! Thinking about buying the new infraction which would make for an equivalent fast vehicle. Thanks for watching ULTRA RC mate!!!!! I appreciate your support!!!!!!
I'm going to calculate the top speed that you could get if your motors were powerful enough:
3300kv * 3S * 4v per cell = 39600 rpm when under no load. Ok so I'm going to guess your wheels are 80mm diameter. That gives your wheels a 8 * 3.14 = 25cm diameter. So every rotation we go 0.25 meters.
Next: 39600 rpm / 60 = 660 rotations per second.
660 rotations per second * 0.25m = 165meters per second. That's the speed it'd go at if your motors ran at their no load rating. (in reality they run a bit slower than what I calculated but it'll be about right)
165m/s is about 596km/hr... so I think it is safe to say, it is geared just a wee, tad bit too high LOL
Say you were aiming for 80km/hr max theoretical speed, then you will want a 7.5 to 1 reduction gearing on it (because 596/80 = 7.5). Now, of course, the motor won't run at its no-load speed so you're going to get a bit under 80kmhr. But that's a starting point, you can take it from there and figure out what works :-)
Your a legend mate!!!!
I did this math's to and got pretty similar numbers!!!!
and yeah its assuming quite a bit, the kv is not verry acurate/ rounded up in china.
Now i am going to try this with brushed motors because they will start up straight away. and not need to oscillate.
I'm sure it will still go fast!!!!
Thanks for Watching This awesome ULTRA RC video Mate!!!!!!!!
I appreciate your Epic support!!!!
I was replying to this but then you tube put it in spam????
anyways all good now!
Nice calculation but it's off due to the mah of the battery and I doubt that esc can push anything with a 1:1 gear ratio you need something like a 150amp esc or higher 5000mah lipo battery and a torque 3800 kv motor
@@CORINKERSTEN there is one problem with brushed motors in general and that is that they still tend to lack a lot of torque when the motors are small in size. brushless motors often have more torque for the size, mostly because they can more easily handle larger amounts of current with simpler coils since there are no brushes(brushes can be like a sparkgab and so tend to by far be the weakest thing in a DC motor by far since they can easily melt, deform or break) brushless motors don't have that. so brushed motors tend to need a lot of speed before they get to their rated ratings. in brushless motors they also need to move fast to get to the rated ratings but they are slightly less sensitive to breaking due to high startup current. brushless motors tend to break due to just getting to hot or the bearings or such breaking, but this also means that the brushles motors can more easily handly startup current peaks.
you can make it sensored yourself by attaching magnets to the wheels that is what I wanted to do. you will need to make your own ESC but a sensored ESC is easy to make(you can also buy them for quite cheap, something like 120A for less than €20, and you might want to have both motors run from the same ESC. while running them both seperate at their optimal efficiency and timings will make it more efficient, tunable and give you more power and speed. having them both run from the same ESC will allow you to save cost in some cases and size and also gives you increased efficiency if both motors are the same quality, if something goes wrong change the sensors to the other motor so the weakest motor has the sensors on it. but running 2 seperate ones should be good as long as the motors are the same quality so that they both produce similar force. if you sensor them you can basically just use a 3 way H-bridge and directly connect the sensors to that, adjust the magnet or sensor placement to get optimal timings and the motor should work perfectly always. speed regulation can be done using PWM.
building a brushed version however still has it's place and certainly is interesting and a good goal, since brushed motors are a lot cheaper and do not need a ESC. so if you can use them in direct drive properly that would really be great. but perhaps it might also be worth keeping the car as light as possible. and perhaps using some kind or semi sensitive spring suspension so the contact with the floor is more constant. this normally doesn't make to much sense other than grip. but in this case it can even out the strain on the wheels. otherwise when it goes over small wobbles the wheel force might change. perhaps howeer you can also do this more easy by just using the spring effect 3d printed stuf has you don't need much just a little so it should be enough. keeping it light is also a nice optimization, for a light car the suspension effect will be more important since if it jumps up at every wobble that won't be nice. in real cars that isn't as much of a problem but rc cars are smaller and so have more extreme responses. since DC motors are cheaper(some years ago in germany they sold 500W brushed motors for less than €2 a piece) you could also make it like one of those big truck trains for moving goods, just then make it a dragracer with many motors direct driving many wheels. just add wheel motor combinations like you have now and eventually so for example a 6 wheel one with 4 wheel drive. that way you have more startup force and more general force. if you add even more wheels as you might know steering might become harder but you could make a bending frame so every 2 wheels(on opposed sides) have their own private section and then they are all connected by pivot points where they can rotate then when you want to turn you just turn al of them this won't really work well when not moving since that would require a lot more force so to test it you should test it while driving or while in the air or such. you could add a RC servo on each of those pivot points to all controll them. or you use one big servo and then use wires. the wires go through the middle over the pivot points so they don't get the rotation from previous parts eventually they go outward in a triangle from the last pivot point before their actual steering location and so when that one powerful servo rotates the entire frame of the car will bend/curve with it like a snake. that way you couldn't make to sharp turns to easily(unless you have a really powerfull motor and spend some work into designing the parts) but it will result in insane amounts of grip in turns and you will keep optimal strength. you could also allow them to move up and down somewhat that way it also keeps good ground contact with as many wheels as possible without needing to add suspension. and ofcource it would make for a interesting rc device.
I wanted to build a similar thing, however I wanted to make a super small fast rc car, as esc I was thinking about either using a broken small 4in1ESC I had laying around, 3 of the esc's in it work, one has a short cirquit so I desoldered the broken transistor but it uses parts that are really old an uncommon and it is really small so repairing that broken one would be a lot of work and it might not work so I decided to keep it for small rc cars or planes where I need 1 2 or 3 esc's. my other option was to make my own ESC, I can do that, that honnestly wouldn't be to much of a problem, only to tune it to get it working properly at full force I would need it to be sensored.
so I got some magnetic switches. I want to test if I can directly out of the wheel, otherwise I might add magnets in the tires and read those to know where the motor is.
I currently have 4 630kv motors, very small 1cm diameter 1cm long there where no specifications on the force and such so I will have to see how strong they are, I they are multistage so that is good for torq. they also where almost around as expensive as directly buying 4 bigger drone motors at the same time, however these ones where really small and having a super fast micro rc car is something I have wanted for a while since those things look many times faster.
and due to low weight I might be able to add other cool things like remote extendable wings, boat mode, etc.(I will probably make my own rc receiver and such, I have one laying around so perhaps I use that one, but buuling it myself will allow for shaping it to the car.
Would the flex of the suspension effect the motors? I want to try something like this but am curious on if it cause the shaft (in the motor)to flex
I thought about using a drone four motor direct drive configuration. This is my mission );o) Would you even need a steering rack if you just altered power to each wheel?
Yeah great idea mate :)
It will be really hard to get it accurate tho
Thanks for watching :)
Hi! I'm building a 1/10 dragster based off these plans as a starting point. How did you handle connecting the ESCs to the receiver? A 2-1 adapter with 1x BEC positive?
Great video like to see it run
Yeah i reckon!!!!
Thanks for watching ULTRA RC!!!!!
lower kv motors higher voltage and smaller wheels maybe helps? idk im noob
Yes lower kv would definetly help, so would smaller wheels, higher voltage maybe but also cause smoke. Sensored motors would make a difference to!!!.
Thanks for watching ULTRA RC mate!!!
Great concept, a bit more tweaking and your there.....nice !!!
Yeah i reckon!!!!!
Thanks for your suport and for watching this awesome ultra rc video mate!!!!!!!
Hi Corin, another great vid, well done :-)
Thanks for checking it out mate!!!!!
Yeah... Great concept!! Just need to work those bugs out. Great job though. 👌🏻👍🏻😎
I think it is a cool idea!!!!
Thanks for watching the video mate!!!!!!!
Awesome:) try an outrunner motor and it will have a little more torque I think. I use a outrunner in my WL144001 and it's awesome torque to break tires loose at any speed;)
Interesting you are probably right.
Thanks for watching ULTRA RC mate!!!
I appreciate your support!!!
Glad you are having fun with your rc!
@@CORINKERSTEN could try gimbal motors, they have gone of torque and work at a much lower rpm. Which means they won't spin out forever and no more push starts.
Did you ever space the motors? I can’t find the next video on this
Yeah i have not made another video,
Thanks for watching this one!!
Thinking about buying the new infraction which would make for an equivalent fast vehicle.
Thanks for watching ULTRA RC mate!!!!!
I appreciate your support!!!!!!
@@CORINKERSTEN couldnt you put copper sheeting between the engines?
WOW, where do you come up with these brilliant ideas ?...lol
Yeah pretty much mate!!!
Thanks for watching!!!!!