Using rc buggy motors

[rm8]

I was one step from buying nissan silvia/ sx200 when I met my wife. So after that I have no chance to bulid and drift, except lego. My wife support this way

So, I ordered 4 buggy motors. Want to make fast light car at 43x20 or 62x20 wheels with rear or 4wd. I dont have RC module. I Want to use existing PF system for remote controlling. May be i have to try light li-pol 11 v from rc models ?

I have no any experience with buggy motors. What do you think? Is it possible to make fast car drifting and "dropping out dirt" under the wheels?

Who have that experience?

P.s. my lovely Wife is better than Nissan

Edited January 2, 2012 by rm8

[Sariel]

RC motors have monstrous power consumption. Two are difficult to power properly. Four are plain crazy.

RC unit is actually the only way to fully power two RC motors (not four - that would fry it). With PF elements, you're going to need a separate power supply for each single motor (and thus a separate IR receiver too), and they will still not run at full power. Plus, you will keep loosing the IR link because IR range is much shorter than RC range. Still, it may be enough for a lightweight vehicle - see this example:

I strongly discourage you from connecting more than two RC motors to the RC unit or more than one RC motor to any PF element - there's a huge risk of frying these pieces.

There actually are Lego sets that answer your needs, except that they are rare and expensive:

this: http://brickset.com/detail/?Set=8366-1

or this: http://brickset.com/detail/?Set=8369-1

Edited January 2, 2012 by Sariel

[rm8]

RC unit is actually the only way to fully power two RC motors (not four - that would fry it).

....

I strongly discourage you from connecting more than two RC motors to the RC unit or more than one RC motor to any PF element - there's a huge risk of frying these pieces.

" Fry" - you mean bb turn on the overload protection or just burning electring?

Edited January 2, 2012 by rm8

[Sariel]

Burning to cinders, I'm afraid.

[nielsvdv]

here you go :)

drifts like hell, yet very controllable. you might want to remove the PTC out of the pf reciever.

i made a variety of versions of it, you can built it smaller and lighter, but i only took pics of this one.

link: http://www.brickshelf.com/cgi-bin/gallery.cgi?f=488840

regerads

Niels vdv

[davidmull]

Ha I'm a big Nissan fan and was a mechanic for them for years :) I also had a lot of sports cars including a Nissan silvia S15 Spec R and a skyline R34 GTT :) drifting is still big in Ireland.

I say build one if u can!

[DLuders]

@ rm8: Have you seen Grohl's orange Carrod? It has Building Instructions , and it has a maximum speed of 13 kph (which is quick). If you mount some SMOOTH wheels (like 1nxtmonster did in his

of his Lego Drift Racer below), you will have lots of fun:

[rm8]

did someone make little cars with buggy motor and PF system? Wanna see how it works...

[DLuders]

@ rm8: Jurgen Krooshoop made a Lego "Small Red RC Racecar" with Building Instructions -- see it here on JurgensTechnicCorner. It has a "RC race-buggy motor with 2:1 gear reduction."

[Saberwing40k]

4 buggy motors ? wait, 4 BUGGY MOTORS!!??!! that's utterly insane. those monsters use so much current, it's not even funny. but as grohl demonstrated with the carrod, you don't need that much. i'm also trying to make a drift car in lego, but using 8070 as a base and using 2 xl power functions motors for power. i wish you luck, cause i have had none.

[rm8]

Everybody relax:) I don`t planned to use all 4 motors at one model:)

Ok, and what about using lipol accu from RC models with Buggy motor?

[DLuders]

Rien posted his test results of using an 11.1-volt LiPo battery in his Power Functions creation, with (apparently) no ill effects: http://www.eurobricks.com/forum/index.php?showtopic=59506&st=0&p=1061034&hl=volt&fromsearch=1entry1061034 . If you want to try a 11.1-Volt LiPo battery pack on FOUR Lego RC Buggy Motors, understand that a single Lego Power Functions REceiver will kick in its thermistor Overload Protection. From the official Lego Power Functions website, Frequently-Asked Question/Answer #12 says:

"Q12. What happens when the Power Functions overload protection kicks in?

A: Overload protection is activated when too much power is consumed from either a Power Functions Battery Box or the IR Receiver. This can happen when a motor is blocked or when too many motors are running at the same time. If overload protection is activated, the Battery Box or the IR Receiver will cut off power to the output until power consumption has dropped under the allowed value. To regain power, unblock the motor or disconnect motors from the output – then turn the Battery Box OFF and ON again. Under overload protection, the green light on the Power Functions Battery Box will still be ON."

This is I would heed Sariel's advice -- don't use more than two RC Buggy Motors. But, if you insist on trying FOUR Buggy Motors, don't be surprised if your creation "dies" within a few seconds after you apply the power.

[dikkie klijn]

A while ago i've made a lego scania racer (sorry sariel you just inspire people )

more photo's: click

I don't have any instructions for you but the concept is quite simple, take an RC motor and attach it directly to the rear wheels. Next take a lightweight battery box (I'd recommend this one) and a steering axle put those together as compact as possible and build a body around it. And voila you have a fast drifting carecar/truck.

Now my truck wasn't designed for drifting but on a smooth floor it does the job. I recommend you to have more weight on the front axle then the rear or using smooth back wheels, just so they can slip.

As a purist I would never use an lipol accu from RC models or anything, I think the Lego rechargeable battery box has about the same weight and performance so that's good enough for me and hopefully for you.

[T_Tank]

I can think of a way to avoid burning up a pf reciever while using multiple rc buggy motors but the question is how much current can a pf switch handle? >.> Solenoid method anyone control BIG current with little current. Thought about trying this with 2 battery packs in series (if possible) an running them to a switch thats connected to the motor an then control the switch with another motor though probably way over complicated for legos.

[Sariel]

A while ago i've made a lego scania racer (sorry sariel you just inspire people )

I can live with that ;)

[Jurgen Krooshoop]

@ rm8: Jurgen Krooshoop made a Lego "Small Red RC Racecar" with Building Instructions -- see it here on JurgensTechnicCorner. It has a "RC race-buggy motor with 2:1 gear reduction."

As you can see in the video, this car can drift a bit.

Edited January 3, 2012 by Jurgen Krooshoop

[Dutch_EE]

You might want to remove the PTC out of the pf receiver.

Niels vdv

I wouldn't do that !

When you then overpower the receiver, you first burn out the receiver, because the H-bridge amplifier in it hasn't much in reserve, and then run into the limiter from the battery box.

If you want to disable that, you're even more mad

With the normal battery box the batteries will drain in minutes. With the rechargeable battery box you will probably have to run for the hills.

When you take out the safety in that box, the LiPo battery can overheat, resulting in a very large amount of smoke, a big flame and maybe even an explosion.

@ Niels,

If you want to know what I mean, look with Google-video or Youtube under 'exploding laptop batteries'

I think that Sariels Scania racing truck proves that with a setup of 2 RC-motors as well as 1 receiver and 1 Lego LiPo-battery for each RC-motor, you will be able to build a very good drifting car.

[Sariel]

I think that Sariels Scania racing truck proves that with a setup of 2 RC-motors as well as 1 receiver and 1 Lego LiPo-battery for each RC-motor, you will be able to build a very good drifting car.

It's Dikke's Scania that drifts, not mine. Mine had exactly the same motors/receivers/batteries setup, but was much heavier and I didn't try drifting with it. Although given that it was very front-heavy, it could probably drift easily with plastic rear wheels.

Edited January 3, 2012 by Sariel

[Burf2000]

I wonder what the top speed you could get out of a Lego buggy. Last year we did a simple drag race at an event which to be honest never went that well with a kid winning with a pullback motor (they are quick)

That first drift video reminds me when I was a kid, used to always take the tyres off and skid it about.

I think I might try and see if through some different combinations you could get a Lego simple car up to 10mph?

[nielsvdv]

I wouldn't do that !

When you then overpower the receiver, you first burn out the receiver, because the H-bridge amplifier in it hasn't much in reserve, and then run into the limiter from the battery box.

If you want to disable that, you're even more mad

With the normal battery box the batteries will drain in minutes. With the rechargeable battery box you will probably have to run for the hills.

When you take out the safety in that box, the LiPo battery can overheat, resulting in a very large amount of smoke, a big flame and maybe even an explosion.

@ Niels,

If you want to know what I mean, look with Google-video or Youtube under 'exploding laptop batteries'

I think that Sariels Scania racing truck proves that with a setup of 2 RC-motors as well as 1 receiver and 1 Lego LiPo-battery for each RC-motor, you will be able to build a very good drifting car.

mine has 1 lipo and 1 reciever for 1 rc engine, and i also use 2. i mentioned the pto because some guy told it to me. i didn't do it, so i don't have any trouble :)

my car drifts like hell, to bad i broke it down, else i would make a video. i made 2 lightweight removable bodies for it. A VW beetle cupcar, and a porsche 911.

it still drifted with the bodie on

[rm8]

mine has 1 lipo and 1 reciever for 1 rc engine, and i also use 2. i mentioned the pto because some guy told it to me. i didn't do it, so i don't have any trouble :)

my car drifts like hell, to bad i broke it down, else i would make a video. i made 2 lightweight removable bodies for it. A VW beetle cupcar, and a porsche 911.

it still drifted with the bodie on

What are the characteristics of lipo ?

I don t understand: you use 1 lipoly with 1 receiver and 1 buggy motor, or 1 lipo 2 receivers and 2 buggy motors. Which is right?

Edited January 3, 2012 by rm8

[nielsvdv]

What are the characteristics of lipo ?

I don t understand: you use 1 lipoly with 1 receiver and 1 buggy motor, or 1 lipo 2 receivers and 2 buggy motors. Which is right?

i use 2 lipos, 2 recievers and 2 rc buggy motor. each motor powers a rear tyre, not needing a diff, while still being able to drift

[Crtlego]

I recently purchased the receiver and remote from the supersonic rc so that I could use the 3 buggy motors I have at their full potential. My first and most simple design mimicked the setup of the actual supersonic rc and used the same size tires. It goes really fast. When using the plastic tires, it is harder to reach full speed without drifting, since they tend to slip and slide. This does, however, make it very fun to drift with. Before this purchase, I often tried using the receiver to power one or two of the motors and the PF receiver would always turn off. Using one motor-instead of two-did not completely prevent this problem. I was more successful when controlling a PF switch with an M motor and attaching the RC motor to the switch than I was with attaching it directly to the receiver. This did make it uncomfortable to drive as the response time seriously lagged (especially since the motor was so fast in the first place).

RC motors have monstrous power consumption. Two are difficult to power properly. Four are plain crazy.

RC unit is actually the only way to fully power two RC motors (not four - that would fry it).

Have you personally had this problem? I was hoping to try out the RC unit with more than two RC motors, but now I don't think it is worth the risk (considering the time I have been waiting to purchase this piece)..

[Sariel]

Have you personally had this problem? I was hoping to try out the RC unit with more than two RC motors, but now I don't think it is worth the risk (considering the time I have been waiting to purchase this piece)..

I was exactly in the same position and I was warned by another builder who actually lost his RC unit in the course of such an experiment.

[TechnicRCRacer]

I have made a couple cars with 1 receiver and 2 buggy motors and it ran just fine. But, I ran 1 buggy motor with 1 receiver and it WOULDN'T RUN AT ALL. But, an extension wire can connect and one technique that I use is to use 1 extension and 1 9V cable: the 9V connecting the motors and the extension from 1 motor to receiver. It is probably bad, but i didn't know what I was doing back then

But, I have a RC battery box/receiver and find it too bulky to use often. I like the smaller cars and the PF system is great for that. I am still fond of L motors, though.