Epic Technic

[TC6] ][WIP] Radical RXC V8

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True, mine was alot higher before, but the weight collapsed the suspension, the rear suspension can't be compressed because the battery box and gearbox compress it. And the front of the car only compresses a bit.

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The chassis now has pretty good ground clearance, 3 studs at the front and 4 at the rear. The suspension is extremely stiff right now so it shouldn't be a problem.

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Some pics:

21.png22.png

I just had to make the GT styled wing

23.png

To fix the lack of power for the 4 Ls, I am going to power them from the AAA battery box, and have an XL connected to the receiver to turn on and of the batt-box

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You'll need an extra battere box I think, because the thermal protection make the battery box unable to governo more than 750ma I don't think that 4 L motors use less than that power ;)have you tried it? And why an XL motor? XD

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Looking good, I had to change my gearbox again, and re-tried slfrodens gearbox format. Sorry I know you originally were using that gearbox, but I managed to get the gearbox to put the power down finally. I'm only using a 3 speed with a neutral mode in-between, but your using a reverse and I think your radical has 4 gears. That's clever by making the spoiler part of the chassis, because if the car does make downforce ;) then it will compress the suspension, and not the bodywork.

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You'll need an extra battere box I think, because the thermal protection make the battery box unable to governo more than 750ma I don't think that 4 L motors use less than that power ;)have you tried it? And why an XL motor? XD

Well powering them strait from the aaa battery box give it sufficient power and I use an XL because that's the only other motor I have left. Or should I use two XLs, I'm just kidding.

Looking good, I had to change my gearbox again, and re-tried slfrodens gearbox format. Sorry I know you originally were using that gearbox, but I managed to get the gearbox to put the power down finally. I'm only using a 3 speed with a neutral mode in-between, but your using a reverse and I think your radical has 4 gears. That's clever by making the spoiler part of the chassis, because if the car does make downforce ;) then it will compress the suspension, and not the bodywork.

The gearbox is a sequential reverse + neutral + 3 speeds. It is still sort of like Slfroden's gearbox but much more compact.

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hope that with an higher load motors won't need more power, i Think i'm gonna Buy The AAA battery box To have more power, maybe The 2V difference between It And The rechargeable will make My truck really batter And morepowerfull

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Right now it has around 49.56 N.cm of torque to the wheels which should give it extreme acceleration. The gearbox is cracking a bit so more improvement need to be done. I have widened the spoiler and added rear wheel arches.

Edited by Epic Technic

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The gearbox is now practically finished and has extremely low amounts of cracking and slippage. The chassis is a bit slow so hopefully Ill be able to add more gearing.

The torque figures ARE INCORRECT because They should be power off of 7.2V not 9V.

Edited by Epic Technic

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The gearbox is now practically finished and has extremely low amounts of cracking and slippage. The chassis is a bit slow so hopefully Ill be able to add more gearing.

The torque figures ARE INCORRECT because They should be power off of 7.2V not 9V.

which are the different gearing? :3 I think that torque doesn't change much, only speed ;)

Edited by PKW

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which are the different gearing? :3 I think that torque doesn't change much, only speed ;)

Not too sure of what you mean here?

Bad-ish news guys the gearbox is no longer going to be servo controlled. The servo just does have enough POWER so I'm gonna use a linear actuator and an XL.

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i Was asking what are the different gear ratios for the speeds of your gearbox (yes i'm not really good at english ahaha) are you sure that the LA is accured enough To make you able To choose the speed when you are controlling you car From distance? There will be the risk of put the moved gear near To move away From the other gears of that speed?

(Again tell me if i've explained well)

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i Was asking what are the different gear ratios for the speeds of your gearbox (yes i'm not really good at english ahaha) are you sure that the LA is accured enough To make you able To choose the speed when you are controlling you car From distance? There will be the risk of put the moved gear near To move away From the other gears of that speed?

(Again tell me if i've explained well)

Well explained!!!

I hope the linear actuator will be good enough but we'll find out soon. In 3rd ( final ) gear, the gear ratio from the motors to the tires is 1:18. The back of the body work is looking good and it is very curvy.

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Ok that means 34 km/h???????? o.O but are you sure that you'll able To move that car with only 4 N.cm and thos big wheels? Because i have more or less 14-16N.cm on my truck and smaller wheels and it can't start in 2nd gear due To the power limit of the BB

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BIG TYPO THERE!!!!!!!!!! I mean 1:1.8

Ahahah funny mistake :laugh: ok at that ratio speed will be more or less 3,4 km/h and about 40 N.cm torque at 9V so all is ok :')

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Yes theoretically mine should be the same as your buggy TheNextLegoDesigner. Because my car has a new 3 speed gearbox, and if the car works properly then its 3rd gear will be 3:5 , and if you simplify that, it becomes 1:1.6666666666667 plus its awd so it will have a quicker launch, but boy if I want to race your buggy, my gear shifts will have to be on point. But epic technic has a 3 speed gearbox as well but his gears will be longer and faster. Hopefully that size advantage will scrub away some power and potential speed, mwahahaaa!!! PKW could its speed really be 3.4kmh?! I was expecting 7kmh considering his gear ratio is 0.2 higher than mine. I'm highly anticipating the day we organise this race.

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haha that's weird mine goes around 5KM/H in high speed on the road.

gear ratio high speed 1-1.66. motor XL

first i could make wrong computations ;)

second your gearing in your buggy is 1.191:1 due to the gear reduction of the differential (I have checked all the gears)

third you have bigger wheels and your theoretical speed is more or less 1km/h

fourth probably i've mistake also this computations (but i don't think)

have you measured your speed? :sceptic:

Edited by PKW

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Actually I miscalculated mine. It should be 1:1.67 according to sariels gear calculator, and it will have 16.92N.cm of torque in 3rd gear. Max torque is 40.3N.cm. PKW could you workout what theoretical speed it would have with the 42000 wheels? Your truck has the most torque: Being a truck. But its quite amazing how you and TheNextLegoDesigner have gotten so much torque from your 2 speed gearboxes. I would only expect that from a tank transmission.

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Actually I miscalculated mine. It should be 1:1.67 according to sariels gear calculator, and it will have 16.92N.cm of torque in 3rd gear. Max torque is 40.3N.cm. PKW could you workout what theoretical speed it would have with the 42000 wheels? Your truck has the most torque: Being a truck. But its quite amazing how you and TheNextLegoDesigner have gotten so much torque from your 2 speed gearboxes. I would only expect that from a tank transmission.

there is a small problem with torque, because philo says that RC motors have 14 Ncm torque and sariel near 2 N.cm so… I don't know what is the real one but i think that sariel made his test with lego batteries and their thermal protection give the RC motor only 2 N.cm torque...

another thing, tanks have small wheel connected to a track so they have high torque, we have bigger wheels, so you have to consider that (if i've understand what N.cm mean) we have a real torque really lower than the one at the axle, so different wheels influence much the speed/torque

Ohw I'm really sorry!! all my computations are wrong :( those are the real one (i've forgotten to consider that i know the wheel diameter not circumference)

@thenextlegodesigner sorry, your buggy speed is about: 3,0 Km/h (your gear ratio is 191.1:1)

@epic technic you 3rd gear speed is about: 10,7 Km/h (congratulation)

leocorno, i've found my mistake calculating your speed that is abuot: 3,73 km/h

hope those are right, all the speeds are calculated at 9V

for everyone that want to know the theoretical speed (m/s) of his/her vehicle this is the formula:

rpmxdiameter(mm)x3.14

------------------------

60000

if you want it in km/h just multiply for 3,6 ;)

Edited by PKW

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I don't think that theoretical speed means too much. Once I made a remote controlled chassis with a 2-speed gearbox. 1:1 vs 1:3 ratio in the gearbox. Yet, I couldn't notice too much speed difference between the two speeds...

Project dropped.

Edited by Lipko

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