dual engine, 3.0/3.8

CeliRA29 · Post by **CeliRA29** » Wed Dec 24, 2003 6:59 pm

well it works like this i was working on a dual engine, then i thought hmmm what if i use different engines, one for torque and one for top speed. running them both would most likey end in a burt up motor. so im going to try and see if i can make a way to run either the 3.0 or the 3.8 and switch during a race, almost like a transmission. that on a booster set, and controller with an anti-boost mod, it will result in two main gears both with "braking" or about 4 "gears" total.

Im still working on the circut, and i will have to run another channel for this, unless someone out there knows a different way to where the second channel is not needed. when i get my mosfets here ill set up indvidual circuts for the 2 motors.

If anyone has any ideas or info feel free express em

viperdout · Post by **viperdout** » Thu Jan 08, 2004 6:33 pm

What of instead of trying to make a tranny, secure both motors onto the gears, and just use a circuit to flip the electric between the two. That way, you start off with the 3.0, flip the switch, the 3.0 turns off, and the 3.8 turns on! If you had a booster, You could make a 4 speed car. This is all theory and bullshit, however, so I don't know if it's electrically possible, at least in this scale.

CeliRA29 · Post by **CeliRA29** » Fri Jan 09, 2004 3:06 pm

yeah thats exactly what i was talking about, i just need to add another channel, for the electrical switch, nothing about it is theoretical, it can be done, for that matter it will be done. i just need to cleane up a drip of sod of my pcb, whoops. but then ill be able to get back to work, i just need to go get a desodering bulb, to suck up my mess. but hey im glad to know that someone supports my idea

viperdout · Post by **viperdout** » Fri Jan 09, 2004 5:01 pm

A really crappy way would be 2 pcbs, 2 motors, and two controllers duct taped together. It'd be ugly, but it would work, though it would also be heavy.

mastercool · Post by **mastercool** » Sat Jan 10, 2004 4:30 am

Im not so sure about the idea im going to give you, but you might be able to do the standard dual motor mod without using the same motor, so at the start the torque of the 3.0 gives the car good aceleration and gives the 3.8 a slight boost and when the 3.0 is flat-out the speed of the 3,8 joins in so you get the aceleration of the 3.0 and top sped of the 3.8.i dont think that that it should take much torque to pull the dragging-behind 3.0.

viperdout · Post by **viperdout** » Sat Jan 10, 2004 9:53 am

mastercool, see the problem is is that the 3.0's still turning and the 3.8 is also. The 3.8 will be slowed down by the 3.0 b/c the 3.0 has more torque. The 3.8 is trying its damndest, but will eventually be fried when the magnetism in the motor forces the brushes to move independently of the shaft. And that's how you'd fry the motor. If it were closer, like a 3.0-3.2, it probably would still happen, just in more time, because the motors aren't fighting each other as much.

CeliRA29 · Post by **CeliRA29** » Sun Jan 11, 2004 3:40 pm

viperdout is iright ive allready just considered running them both, but yeah that would burn one of the motors the 3.8 would alwayz take over, and the power running through the 3.0 would cause friction, and bog down both, a switch has to be used, plus your batters would drain really fast if you had reverse friction goining on. thats y the motors would fry

CeliRA29 · Post by **CeliRA29** » Sun Jan 11, 2004 7:02 pm

well i just realized a simple way to run two different rpm motors without adding another channel, just use a simple 555 timer, and have it switch after a sertain amount of time say 2.5 five seconds when the 3.0 has reached top speed, and then switch the power over to the 3.8 wich would then cause more acceleration. basically the timers witch would restart if you realease the foward button, dropping back down to the 3.0 for a 2.5 sec torque push=drift. basically the whole thing would be a automatic two speed, im not sure if it would work on a booster, the bost button may cause the timer to restart, and drop back to the 3.0. the circutry for adding the 555 would be very simple, and small. i may persue this type because adding a new channel is going to suck.

viperdout · Post by **viperdout** » Mon Jan 12, 2004 5:44 pm

The only prob is slowing down and getting torque after the apex.

CeliRA29 · Post by **CeliRA29** » Tue Jan 13, 2004 7:52 pm

actually to be realistic it would only take like 1.5 seconds for the 3.0 to max out under normal car weight. so you could with this type of circut the change the timing for conditions of the track, for a track with tight corners and short straits, set a longer time so you can drop down to the slower motor by a short release of the foward button. on straights full throttle as the 3.0 times out and the 3.8 kicks in. on fast tracks with long corners you would set shorter timer, to utilize the 3.8. the 3.0 would only help for acceleration at lower speeds, or as to even act as brake due to the fact that a release of foward restarts the circut, resulting in a short drop into low rpms causing a very controlled braking effect after a shot period the 3.8 kicks back in. very simple, im in the process of making this beast come to life using a lxx single speed and a 200mah battery, and some spare crap i have sitting around.

viperdout · Post by **viperdout** » Tue Jan 13, 2004 7:57 pm

Well, good luck!