M07 Electrics

Hi,
I made some progress with the M07 electrics last night. I looked at the options which are basically

1) Buy a twin motor esc - two expensive and will only use it once.
2) Wire two motors in series - can do this off a single esc, but only get half the revs so very slow
3) Wire two motors in parallel - you get full revs, but the two parallel motors appear as a single motor with half the turns so I would need around a 10 turn ESC to run two sport tuneds.

I am going with a fourth option which is to run two sport tuneds connected to two teu101 ESCs driven from a single lipo and a single receiver. This option is not as widely discussed on the forums, but I can't see why it wouldn't work and I can build it easily from the parts I already have.

Last night I made a Y lead to come of the battery and connect to two ESCs, I also fitted a Y-lead from the receiver. I will do a quick bench test tonight, but still need some steering parts and need to replace the current silver cans with sport tuned motors before I take the car out for real.

Duane.

I am not sure if the principle is the same but I have wired planes with twin EDF's on a single battery/rx configuration. In these cases it is suggested to remove a single red lead from one of the motors. I believe this is more a case of protecting the BEC functionality of the ESC's but is more pertinent in brushless motors. I am not sure how it would work with the brushed setup, but check out the airplane forums, you might find more info there as it is prominent in planes. Most people use BL now, so your search would need to be specific to brushed.

Hi Andy,
I had seen one reference to cutting a wire to protect a BEC, but I was skimming articles at the time and couldnt find it again when I had settled on this solution. I will have another look.

Thanks
Duane.

"If the ESCs have internal regulators (bec) power the reciever and servos, then you also need to mod one of the ESCs plug into the reciever. On one ESC you must remove the red wire from the plug...if you do not both ESCs will try to provide power to the reciever, which is not good. Some guys snip the red wire, but then if you want to use the ESC on its own in a future project, your screwed....the solution is to lift the plastic section of the plug and push the wire and its crimped connector out of the plug. Then you shrink wrap the lead so its there for use later if you need it. "

Looks like they mean cut one of the red wires from the BEC so that you dont have two ESCs trying to power one receiver. As the BEC is through a seperate plug on the TEU101 I dont think I will need to do this.

i think it's the same principle as Motor on Axle Crawlers. . . . which strawb has. . .

True, Strawb are you out there ?

Duane.

Duane here is a wiring diagram for dual tekin esc's, but essentially the principle should be the same

I wouldnt power the rx through the esc, just get a external BEC instead, safer for your electronics

You can also use a y-harness for the 2 esc leads if you only want to use one channel to control the esc's.



Diagram courtesy harley on rccrawler.com

Pretty sure that the TEU101 doesnt provide a BEC through the throttle channel so its a lot simpler, no need to cut anything and can just use a y-lead. Will check with my meter this evening and if all goes well I will get it running.

Duane.

Duane you're right TEU101 doesnt have any internal BEC, so it should be pretty simple.

Very much looking foward to getting home and trying the M07. Lets hope it doesnt end in a bang !

nice project there duane! hope it works

Haven't seen a single pic, ergo....it doesn't exist

Tried the M07 on the kitchen work top, too many wires but no smoke. It sounds good as well.

If I get my act together in the next half hour I will pull two sport tuneds and a servo out of my other minis and try it out in the street.

Looking forward to some twin motor acceleration and four wheel braking.

Duane.

paul wrote:

Duane here is a wiring diagram for dual tekin esc's, but essentially the principle should be the same

I wouldnt power the rx through the esc, just get a external BEC instead, safer for your electronics

You can also use a y-harness for the 2 esc leads if you only want to use one channel to control the esc's.



Diagram courtesy harley on rccrawler.com

this diagram is basically what i use for running dual esc's on both my xr-10 and berg ....

if you need help wiring em up just let me know .... its a bit complicated at start cos you dont wanna burn up 2 of everything .....

basically ... the BEC gets direct power from the battery ... powering the servo and the Rx .... wire the red and black wires of the esc's in series together ..... pull out the red wires of the esc's which go to the Rx and your ready to go ....


this set-up would be best taken advantage of when your running a futaba 3pk or 4pk .... the proportional attributes of the radio maximizes the capabilities of both esc's

sorry ... ive been away ... been really busy ....

like i said ... holla at me if ya need help or if you need to see how i wired my rigs up

cheers

Just been out in the street with 'The Birds Nest', the name is on account of my wiring, there is a lot of it.

It is stupidly fast, it power slides around corners and will fish tail for 20 feet out of a corner. All very cool in a short wheelbase mini.

Everyone should have a M07 aka 'Birds Nest'.

Duane.

Photos please!

pics and vid or it didnt happen

Hi,
Took a couple of pics on the way out this morning, unfortunatley it really does look like a birds nest with some recognisable bits of m-chassis visible through the chaos.

I am still not sure what to do with this car, I can stiffen it and lower it to run slicks at Meydan or leave it high and soft with rally blocks. It reminds me a bit of the old Group B rally cars, in particular the Metro 6R4 - small, over powered, unpredictable, a little bit mad.

http://www.6r4.net/site/index.php?option=com_content&view=article&id=2&Itemid=3

There is a company 'Control Freaxs' that specialise in 1/10 RC Rally Shells and I see on there website they are planning a 6R4 body shell to fit the m-chassis. If that ever makes it to production it will find a place on this car.

http://www.controlfreax.com/buynow.aspx

Not sure if the Group B cars or rally cross were popular outside of the UK, but check out the engine in the 6r4 here and remember a metro is smaller than a Swift.

http://www.flickr.com/photos/26816751@N03/3327360831/

Duane.

So ugly I didn't want to post it, but here it is - 'The Birds Nest'. You can see the two TEU101s mounted in the center of the chassis, there is something very cool about individually switching two motors on before you run your car.



From the other side, showing the two sport tuned motors


My SWB Rally swift on the M07 'Birds Nest'


And here are some videos of the Group B Metro 6R4 that came to mind the second I saw the twin motor m07 blast off

Group B Metro 6R4 action here

https://www.youtube.com/watch?v=C2PhpajCU3w&feature=related

and here

https://www.youtube.com/watch?v=e01xeFetv_g&feature=related

Really hoping that 'Control freax' release the m-chassis 6r4 shell

See you at Meydan

Duane.

Just tint the window on the body shell and the birds nest will hidden

look forward to seeing it in action! are you coming down to meydan this weekend?

I hope to make it Meydan this weekend. As for the birds nest, if I decide to give a permanent home to the M07 project I will get a single low turn ESC to replace the two TEU101s, that will get rid of one regulator, two switches, two BECs, two throttle channels and a throttle channel Y Lead. Things should look a bit tidier then.

Duane.

Just stump up the cash and get the Tamiya Dual motor ESC....we know you are fill of money..LOL

Looks cool, and uber-cool as a project...myself, I would buy a 4x4 mini and be done with it...lazy, I know.

BTW, anyone considering an M06 anytime soon?

I saw some Dual Motor ESC in T&U before try asking if they still have..

Cool project Duane!

you only need one BEC duane

plus dual esc with proportional mixing is the way to go!!! under drive and over drive in a press of a button!!!!

Hi Strawb,
I am only using the one BEC, the other is taped up. As the TEU101 BEC is just a straight pass through from the battery and I am using a LIPO I have the TEU101 BEC Running through a regulator to give a stable usable voltage to the receiver.

I will eventually try the mixing idea, I know that it doesn't work with grip tyres, but might with drift tyres. With grip tyres the two motors are always helping each other, whichever motor has the bias in the mixing will be using more current because its doing some of the work for the other motor which will draw less current but thats the only effect you get, no easily tunable handling. Like I say it might be different with drift tyres where the road surface is not acting as a direct coupling between the two motors.

Duane.