Hey guys im starting to try and learn new stuff as i get familiar with the trucks you run in PRO. With moa trucks i gather you can have one esc that controls both motors or an individual esc for each motor.

In the first option, one esc for both motors, can any esc do this or only do only certain esc's have the cabability?

In the 2nd option i dont really see an issue exceft for needing an addittional channel on the TxRx for the 2nd esc. In this setup does it mater again the type of esc or are some better than others for this application than a conventional esc in a truck with one motor?

Obviously the main advantage of 2 esc's and individual motor control is being able to run front and rear motos at different speeds.


Second part i want to know about is electronics based Digs vs mechanical digs.

Obviously there are mechanical digs actuated by a servo and a mechanical device or there are digs opperated eletronically via the motors by locking the front or rear motor.

Mechanical types i imagine are more robust but i asume electric versions are more compact and help to save weight.

I think from what i have seen most of you use the mechanical style with a servo but as iam not heaps familiar with your Pro rigs i do not know 100%.

Are the any reasons you guys use a mechanical means to opperate a dig over an electric method?

Thanks for any help advice given guys. Just tyring to gain a little knowledge in a class i havent run in so the dynamics of some aspects of your trucks would be very different and some very similar.

Thanks BMT sort of makes sense but still question loll....

Twin ESC's: you really want a radio with channel mixing to take full advantage of driving the motors at different speeds, otherwise I wouldnt bother.

One ESC: needs to be a decent current rating to run two motors, also so it will help reduce clod stall a bit by running an ESC with a high current rating. Clod stall can be governed by using different size pinions, introducing a resistance in the cabling (ie cable size or length), or even meshing the pinion gear a bit harder against the main gear to increase its resistance.

Digs: either microswitches operated by a servo or an electronic unit or twin speedies. Micro switches are bulky (with wiring) but cheap. About $3.50 ea. Electronic digs are dearer but more compact.

Thankyou guys, your explinations do make things a bit clearer. Im still a little unsure on channel mixing. How many channels are required for channel mixing? Why do you mix channels?

Seperatly when you say to run each motor on its own esc... Do they each require their own individual channel or can they operate on one channel via a y harness or similar?

Yes Linc i did have my terminology mixed for Digs and MOA and shafty trucks, Thanks for clearing that up.

I was reading on digs and patricually the punk dig on rcc as Bushy referanced it in a post and i dint know what they did or how they operated. From what i have read on RCC they seem like a good idea. Ill have to do some research on themicro switch method as this is now a new term for me.

Again i may have my infomation mixed up a little but from what i gather of you run a punk dig a 3 channel radio is sufficient for steering, driving and the dig.

When you use a micro swithch methodyou describe is a 3 channel also sufficient?.

This all stems as i have been reading what you have written in this forum and whats been written on rcc(is heaps) about the new XR10. If i am to consider lookign at getting one in the future i would like to have an understanding of what im getting into before going down the path of pre ordering or prchassing at a later date.

Ben

Hi Ben,

To answer your last questions, you will need channels on your radio for every device you want to control.
This is either ESC's, mechanical dig, or electronic dig.

If you run a Y harness for the ESC in an MOA setup then you will still need a channel to control the dig device you install.

With regards to mixing on a dual ESC rig;
Ch1 = Steering
Ch2 = Throttle - Front ESC
Ch3 = Throttle - Rear ESC

Your radio then does electronic mixing on Ch2 & Ch3 to give you control of the throttles. You can have a 100% mix on both Front and Rear and you get standard 4WD.
Or, you can change the percentage of the mix and get different speeds on either front or rear. You also set the mix to 0% to the rear to give a DIG.
You do all this by assigning the mixes to switches on your radio. Some radios dont allow you this number of mixes, dont allow the 3rd channel to be proportional (for a throttle), and don't allow you the ability to assign mixes to enough switches, or just dont have enough switches (or buttons).

For a mechanical DIG setup;
Ch1 = Steering
Ch2 = Throttle
Ch3 = DIG

You would ideally still want a 3 position switch for the DIG so you can have both Front or Rear DIG's.

For an electronic DIG setup;
As far as I know same as mechanical DIG. Just no micro switches, or servo - it's all replaced with a small electronic device.

In my opinion, to get the best out of a MOA setup you need dual ESC's and a radio that can handle all the mixing. This gives you far more control over what your rig is doing and gives you the ability to adjust drive to wheels if/when required.

Cheers,
Mike.

Thanks Mike i may just have to come and learn some practical knowledge from you boys at the next comp for pro rigs. I, still enjoying scale and sportsman but another challange may be around the corner for me with you boys in pro if time and money(budget allows).

Yes the Mrs knows about this and i have a set budget in concrete if i decide to go down the XR10 path....

Ben, I have a RC Punk dig/steer computer sitting here I will not be using. I was going to use it back when you needed 4 channels for two lots of steering and two ESC's, but I only have 3. It can be easily rewritten to just be a dig controller if your radio only has a 2 pos 3rd channel or no mixing.

Mike answered this, but I thought I'd just try and make it a little clearer.

On a MOA truck, there are two ways to go when it comes to getting 'digs'. But lets more specifically call it 'individual control of front and rear motors'.

The most basic form of control is just turning off the rear motor to create the dig effect. The best way to do this is a single esc powering both motors and having a servo operate a microswitch to cut power to the rear motor. To do this, you need a 3rd channel with a 2 position switch (on/rear off).

The next step up from this is to be able to switch off the front motor as well as the rear motor. You can still do this with a single servo operating two micro switches, but you need a 3rd channel capable of 3 positions (front off/on/rear off).

The next step up again is using a PunkRC Dig unit, which more or less gives you the same result as the above, and you still need a 3 position 3rd channel to operate it.

Another less cost effective way to achieve the same on/off effect for the rear or front motor is using another esc in the 3rd channel powering the rear motor. But to do this, you need a radio that make its 3rd channel copy (mix) the throttle channel. At least, you want to be able to switch this 3rd channel from 100% mix to 0% mix to give you the dig effect. But as Clarky said, its really a waste of the potential a 2nd esc can offer.

To get the maximum control of the individual escs, it comes down to the radio you have. You want a radio that can allow you to set the rear to 0% at the flick of a switch, as well as adjust the amount of mixing from 100% down to 0% in set increments so you can say run 50% rear power for a 'half dig' effect. The ultimate radio would also allow you to make the same adjustments for the front motor. As far as I'm aware, there are only a couple of pistol radios capable of doing this: the Futaba 4PK and the Nomadio React (possibly others, but not 100% sure). But there are many stick radios that can achieve this.

Put simply, if your radio can't achieve the above, don't invest in a 2nd esc. I should also point out that using a microswitch or Punk dig switch and a single esc is actually very effective on its own.

I also typed all this one-handed.

Feel free to call in again Ben. It may be easier to show you in person.

The last time I got the Berg going (not counting the comp ) I found by mixing the rear esc (ch 3) to the front (ch1) with a 55% proportion (rear end is always being driven just a ltttle over half the speed of the front) it could do most things and turn on a dime. I had my 3rd channel knob assigned to control the proportion of the split between channel throw, and another mix that had the rear mimicking the front exactly. By deactivating both the mixes it was front driven, rear drag brake locked. By activating both the mixes at once I could use the knob to overdrive the rear end. That's why I was not too impressed when it baulked on the line

If it sounds a lot more complicated than Sportsman, well, it is But also, it's the enjoyment of setting up a sophisticated truck with almost endless user control. A fully blown dual motor Sportsman rig is hanging around the blurry line between rc trucks and simple robotics.

Thanks again guys. Firstly BMT if you have that Punk Dig unit lying around i could be intrested as it seems a simple method of working a front and rear dig.


Linc your explination is quite clear, thankyou. THe mircro switches sound fidely but at the same time once i see in practical terms im sure it would be quite simple.

The radio i baught recently i dont think has mixing but i can not be sure. It does have a 3 position option on the 3rd channel and it can also have a 5 position on the 3rd channel. Essentially if i go down the XR10 path im hoping i can start off with the radio gear i have now just be getting another Rx when i purchase the truck.

I do understand that as many channels available is the best option and as BMT said driving Pro trucks is more complicated, but i would like to start somewhere and if i get hooked go further from there. As scale and sortsman have me hooked i asume Pro would be the same.

Clarky i cant today but i may take up your option an dcome around som etime to have a look thanks mate.

Ben, if you have mixing, don't worry about the dig computer. You will get much better results with the radio functions. If not, it's here.

Well Ben,welcome to the world of twin motors.
So far have used single esc-bad bad bad-no dig /bad quad stall
twin esc's/twin stick radio-not bad at all,infinate control over motors/drag brake wasn't strong enough for proper dig but that was 3.2 tyres.
Looking at giving te "punk dig" a go next-saves me carrying two radios.Have to see what happens.

Untidy example of a microswitch front and rear dig

So when the switches get activated what do they do??

Cut power to front or rear motor. And if you wire them correctly, can actually short the motor that you cut power to, to improve the locking effect of that motor.

This is the last one I made.

Hey guys obviously more to pro than i first thought due to electrical setup. Would like to have a walk through of your trucks and wiring at next comp. I dont expect to get this sorted overnight but as i mentioned previously i want to at least have an idea what im getting into if i order new rig and acessories. Thanks to you all for your openess in discussing and pics of the finer points of the electrical setup. Sounds alot of mucking around but is probably quite strait forward and logical.

Hey Ben,

No doubt that the main difference between a Sportsman truck and a Pro truck is the electrics, as that is the main defining difference between the two classes - the number of channels.

My personal opinion though is that running two separate speed controllers and motors is probably a little easier to wire than setting up a dig switch. It's kind of like wiring two Sportsman trucks into the one truck.

I'll give you a tour of my MOA Losi at the next comp if you want, and I'd probably also have a look at Clarky's Berg, as last time I checked, he was running the dig switch setup with a single speedie.