Im ok, I was trying to do windmills on top of an ab ball, fell off backwards and yanked my neck and back. Wish I was still 16 and made of rubber.


On your startup with the DD, when do you call it a good startup? When you can punch it and get instant acceleration every time? I will post pics this evening of my build, seems that it will always start up but the tire size has a lot to do with how fast I can roll into the throttle.

Instant Acceleration from WOT at any speed is the goal. With the 80amp ESC, I feel like the surge might have been overtaxing. WOT would squeel at anything less than about 5 to 10mph. I know the 80amp ESC was being pushed to it's limits, since If I ran HARD, it would thermal.

Tonight I'm going to install the Monster Pro 125 amp ESC with a 2700uf Cap rated at 25 volts. This is Novak's pick of Caps, so I'm thinking it will be enough.

I got some thermal compound for the base of the ESC. This will insure a really good thermal exchange with the Aluminum Mount.

One thing I noticed with the 80amp ESC, if I had the wheel turned and tried to start from a dead stop, it didn't like that for some reason. Voltage drop from the internal BEC being loaded? Well that's gonna be a thing of the past too. I will install the 10 amp CC BEC as well. This will also remove ESC heat added by the internal BEC.

I also found a neat little micro toggle switch at Radio Shack that I think I will put on the ESC for on/off.

I plan to shorten the motor/esc wires and use the connectors that came with the Monster Pro. They are alot bigger. 5mm I believe and have a higher amp rating.

In light of the problems that plaque the Mamba Max setup, I'm sure the 4mm connectors are barely holding their own in this setup. In fact, if there is any internal arcing going on inside motor connectors, this will make it cog as well.:yes:

Do you have a castle link to program the ccbec?

I set mine to 6.5 volts in my revo and am running a 9001 airtronics and a futaba 3050 and neither even get warm with that voltage. Plus the airtronics servo will almost turn the truck if you hold the front wheels still!

You will notoce a big difference eliminating the internal bec on the quark. I have even done it on my 65 roadster and it works well. I have a few $7 CCB (chinese crap becs) and when wired and placed correctly they will work without interference. The ccbec is far superior and only about 3 times the price, a killer deal for a necessary component!

The internal bec just can't keep up with the demands a high torque servo(s) can place on it. They work ok in 10th scale vehicles on 2-3s with medium duty servos, that is about the best you can hope for.

Hey Sike, I have been away on a small getaway for the past week.... anyways, I was wondering how the direct-drive truck is coming along? Anything new? (being lazy, haven't read the posts)

Welcome back ZPB! I've missed you man. Hope you had fun on your get away.

Things are going GREAT! I'm at the kitchen table tonight installing some new upgrades.

You need to catch up here. There are some Video's back a page or two.

I'll be shooting some more as soon as things dry up some around here. :yes:

I don't have the Castle Link yet, but I'm happy with the 5.0 volt output. Just as long as I get that extra heat/amp load off the ESC.

The good thing about this is, if I do decide to go with a HV setup, I have the BEC at least.:yes:

Ok, here's the new setup.

1. Quark Monster Pro 125 amp ESC - I added a 2700uf@25volt 105C Low ESR Cap to the power lead. It's a Novak product. It adds plenty of crackle when I plug the batteries in.

Also added is a Micro Toggle Switch. I like it better considering my mounting options.

The motor leads AND the ESC Power leads have been shortened. Also used are the connectors that came with the ESC. They are much larger and more up to the task than the previous 4mm connectors.

A Nice coat of Thermal Heat Sink compound was applied to the ESC before it was strapped in. This should provide the best heat transfer possible to the aluminum mount.

2. CC 10 amp BEC module - This is good for up to 6S Lipo with how it is currently wired.
http://i160.photobucket.com/albums/t...m/DSC06680.jpg

If your theory isn't correct, another one would be that with the wheels fully turned, the front driveshafts are binding a little bit (happens with many trucks/buggies), causing an increased initial load to the motor. As you know, any extra load on startup will not help with cogging.

sikeston34m,
Do you have any interference problems using the 27mhz am radio gear? Very nice work too by the way.

Thanks Desmo.

No Interference Problems at all so far.

Your probably onto something there. I'll have to take a closer look at that.

I was checking it over last night, thought I had a bad wheel bearing. There was alot of slop there. It turned out to be slop in the upper/lower ball joints. They all needed readjusted. All of the slop is gone now. :yes:

This Post is mainly directed at JohnRob since we are both working on doing custom motor winds, so bear with me.

After winding a few stator poles with 4 strands of 22awg @ 5 turns on the 3530, I see this is gonna be tough. It's hard to get it in there and make everything lay neat. Each strand has to behave and lay parallel without crossing any of it's "neighbors".

I think I see now why the person behind the PowerCroco site is going with just one strand. Even though it's stiffer, it should be easier to make lay in the turns and easier to manage.

In researching, I have constantly seen references to copper density, wind resistence, and the effects of not having good values as being "copper losses" Copper Losses result in a motor that runs hotter than normal and one that is less efficient.

To Minimize copper losses, one should have the most amount of copper on each stator pole looking at the Total Cross Sectional Area of the winding. In other words, each stator pole must be as full as possible AND have the least amount of resistence in the wind as possible.

I'm going to try to wind with just one strand to hopefully gain some on this. I'm willing to put out the extra work and effort to do the wind and am not too worried about it "being easy on my fingers" LOL

In order to know what awg of wire to use, first some things must be calculated.

By taking the Cross Sectional Area of a given awg of wire, then multiplying by the number of strands used in an already succesful motor, we should be able to come up with a single strand that is the same as using all those multiple strands.

CSA walks hand in hand with wire resistence also. :yes:

Here is a chart that was pulled from the net that shows data for various wire sizes used in motor winding.

http://www.powerstream.com/Wire_Size.htm

30awg Dia. .01(.254mm) Ohms per 1000' 103.2 max. amps .86 Cross Sectional Area = .0000785
28awg Dia. .0113(.287mm) Ohms per 1000' 64.9 max. amps 1.4 CSA = .00010023665 x 20 = .002004733 20 strands @ 5 turns = .010023665 Total CSA
26awg Dia. .0159(.403mm) Ohms per 1000' 40.81 max. amps 2.2
24awg Dia. .0201(.510mm) Ohms per 1000' 25.67 max. amps 3.5
22awg Dia. .0254(.645mm) Ohms per 1000' 16.14 max. amps 7 Cross Sectional Area = .0005064506
20awg Dia. .032(.812mm) Ohms per 1000' 10.15 max. amps 11
18awg Dia. .040(1.02mm) Ohms per 1000' 6.38 max. amps 16
16awg Dia. .050(1.29mm) Ohms per 1000' 4.01 max. amps 22 CSA = .0019625
14awg Dia. .064(1.62mm) Ohms per 1000' 2.52 max. amps 32 CSA = .00321536
12awg Dia. .080(2.05mm) Ohms per 1000' 1.58 max. amps 41
10awg Dia. .101(2.58mm) Ohms per 1000' .99 max. amps 55

Area = (pi) x r2
In English, this formula means "area equals pi times the radius squared." A circle's radius is one half of its diameter, or one half of what you get if you measure all the way across its widest part. "Squaring" something means you multiply it by itself. Pi is a number that roughly equals 3.14159.
A = 3.14 x Radius x Radius Radius = Diameter/2

I have been figuring and adding Cross Sectional Area values to the chart.

The 3530 motor was wound using 20 strands of 28awg wire.
This is a .002004733 Cross Sectional Area of Copper.

14awg wire has a CSA of .00321536
16awg wire has a CSA of .0019625

16awg is ever so slightly less, with 14awg being about 1.5 times that.

I'm going to order some more wire. Copper Density and efficiency can be improved if 14awg will fit. But even if 16awg is used, it will duplicate the density/efficiency scores that are on the market now.:yes:

Give the 16awg a shot, it should be a lot easier. Are you using any winding tools? I whittled two chopsticks flat for smashing and pushing the winds in, then I have two flat sticks that keep the winds tight while I move around to the other side. The ends aren't as important as the fill between the slots.

Got any data on the CSA of 5 strands of 22awg? My figure shows .002531153, which is still less than 14awg. Looks like we need to find some 15.5 or 15awg wire.

I'm going to be making some winding tools. In practicing, I was using a small screw driver and some needle nose pliers that have teeth in the jaws. That don't work. It's way too easy to create tears in the wire coating.

Something I've noticed about making the decision on just how large the wire can be, We need two wires to lay side by side in the lower valley of the poles. Like the Scorpion 3032 that the Croco guy wound. While reading the website through a German translator, he calls it an 8wd with 1.0mm wire. According to him, This is a 550kv wind, but tests from person to person are inconsistent. This test was probably done with a working load of who knows what.

1mm wire is 18awg. Take a close look at this picture. If too large a wire is used, the bending radius won't be tight enough at the ends either.
http://i160.photobucket.com/albums/t...ocowinding.jpg

Each size of stator is different with how much of what size wire will fit.

I'm really thinking about getting another AXI 4120 motor to rewind. The more I think about the custom 4130, the more I feel like I'm going to have a motor that is going to draw so many amps, the Quark 125amp Monster Pro won't even be enough on 4S Lipo. Aside from this, trying to figure how many kv it will be is a guess at best, since there isn't a 600kv to 700kv currently on the market to compare this to. I think the amp draw would be out the roof, so would performance, but this is why motor builders move up to High Voltage to get more performance. It's all about keeping the amp draw manageable.

Top speed is great with the 4120/14 on 4S. Being 660kv, it's much easier to come up with a wye wind that will be the same kv and draw close to the same amperage.

"Got any data on the CSA of 5 strands of 22awg? My figure shows .002531153, which is still less than 14awg."

I quickly figured the Single Strand CSA of the current Scorpion offerings for the 3032. Check this out.

3032-8 988kv 27 strand 8 turn 30 awg .0000785 x 27 = Single Strand CSA = .0021195 Total CSA is .0021195 x 8 = .016956
3032-10 823kv 24 strand 10 turn 30 awg .0000785 x 24 = Single Strand CSA = .001884 Total CSA is .001884 x 10 = .01884
3032-12 687kv 20 strand 12 turn 30 awg .0000785 x 20 = Single Strand CSA = .00157 Total CSA is .00157 x 12 = .01884

5 Strands of 22awg is a CSA of .002532253
4 Strands of 22awg is a CSA of .0020258024

It's easy to figure Total Cross Section Area.

Single Strand CSA x Number of turns = Total CSA

The Greater the Total CSA, the higher the amp carrying ability, the more power it will make AND the more efficient the motor will be.

With the 3032, shoot for a Total CSA of .01884 or better.

The German guy's Croco motor wound with 18awg has a Total CSA of .010048

This tells me the Scorpion Factory winds are more efficient and make more power than the Croco motor.

I think I will get some short samples of each awg wire and see how many strands of what will fit the best and work the best according to the figures.

The 4120 winding should be easy enough to convert to a 660kv Wye wind and should tell us what we want to know. I think I'll shoot for that. :yes:

It IS very difficult to determine what the KV will be before winding, although basing it from similar sized stators and magnet strengths does help. The hardest part is that every stator fill is different. I don't think I can have any more wire pushed into my stator, the 5 strands of 22awg is such a tight fit I have to thread some of the last winds in.


I kinda eyeballed the fit of my wire. Put in a chunk of strands and said "that looks enough". My math was that 40 strands would barely fit.

That's an 8 turn motor? :oh:

An 8 turn factory motor is 988kv. Your motor's amp carrying ability should be better with a Total CSA of .020258024

Good Job! :yes: You beat the factory on fill.

Maybe off topic.. Lehner won't fix my 2280.. you guys know how to rewind inrunners?.. my 2280 needs a new can or to be rewound..

Lehner is slotless if I remember. You need a winding jig and press for that, those are compressed and baked windings.

Yeah, I went with an 8 turn so I could compare it to the 8 turn Wye I have from the factory. I still haven't finished the last phase, another 1.5 hours of winding.


If you want to get a ballpark for kv, a motor that is twice as long with the same wind count will have half the kv. Same formula works for a motor that is 1.5 times as long. As for wind count, the formula is really stinkin complicated so I'm not going to even attempt. When you change stator diameter it messes with things. When you change magnet strength it messes with things too.

Progress!
 

I've been making some progress winding the 3530 stator. This one will fit in the E maxx, so that is the platform I'll be testing it on.

Factory wind was 20 strands of 28Ga. at 5 turns. This yielded the following specs:

715Kv
Max Voltage: 30 volts (8S Lipo)
Max Amps for 20 seconds: 55 amps
Max Continous Watts: 1000 watts
Efficiency: 85%

In motor winding, the awg of the wire versus it's max. Amp rating tells that it is REALLY being pushed hard.

In the factory winding, 20 strands of 28 awg are rated to carry 28 amps even though the motor is given a 55 amp Burst Rating. See? This cuts efficiency and generates heat.

I am just dying to know how wye versus Delta Terminations perform. I know how the Delta performs. I've got a good taste of that. So with this wind, I'm working with 22awg wire. 3 Turns with 7 strands with a Wye Termination.

On my winding, 7 strands of 22awg is rated to carry 49 amps. In Factory spec comparison, this translates into right at 100amp Burst rating. Since amp rating are based on resistence, I feel good about this wind.

Here's what it looks like so far.
http://i160.photobucket.com/albums/t...m/DSC06684.jpg
http://i160.photobucket.com/albums/t...m/DSC06682.jpg

Yep, I'm using the Broom stick trick. :lol: I first lay out all 7 strands, tape one end, then I roll them up on the broomstick EXACTLY parallel, the way I want them to lay in the winding.

It really helps to pull the wires and make a nice neat radius to make the turn with.

As you can see, I've removed the bearings, installed a bolt with a couple of washers. I also numbered the poles so I can be SURE that I wind according to the DLRK diagram.

I clamp the bolt in a vise, wind a pole, then turn the stator for a fresh grip on the bolt.

I can't imagine being a motor winder and doing this all day! LOL

Now to make the terminations.
http://i160.photobucket.com/albums/t...m/DSC06687.jpg

My first Wye wind. She's done! :yes:

What's even better is, it runs! :lol: Seems to be pretty smooth just running no load.

The Motor on the left is a Factory Wind.
http://i160.photobucket.com/albums/t...m/DSC06690.jpg

That is really cool. Nice work. Do you balance the rotor or anything?

Since I just rewound it, the factory Rotating Endbell was already balanced.

The Stator part is stationary. It doesn't turn.

Precisely. :yes: And nice work Sike! Makes me want to get another project going for a slotless/halbach array Bl motor... they have up to 98% efficiency these things!

Thanks ZPB. How's your Revo doing these days?

We finally got a break in the rain, and even though those nasty puddles are scattered around, I had to try this custom wind.

I have ran the factory 5 turn Delta wind on the 3530 in the E maxx before. It performs well. I ran it alot, so I'm really familiar with it's performance.

Today, I found out how the 3 turn Wye wind performs. It runs cooler than the Delta wind. I know the math says that the KV is supposed to be slightly lower, but top speed and acceleration are much better.:yes:

This motor makes MORE power! It also starts better.

I can easily take off in 1st gear OR 2nd gear. I can grab WOT from a standstill in 1st anytime and it responds perfectly.

When starting in 2nd gear, it still doesn't like the 1st or 2nd step in the throttle, but anything beyond that is just fine. I can grab WOT starting in 2nd gear! It blasts out of the hole with great control about 90% of the time. The other 10%, it kinda screams at me like Metalman described his was doing.

My conclusion is, several things add to the improved performance.

1. Lower internal winding resistence. Any wind irregardless of number of turns or termination will perform better, the lower the resistence is. I have a feeling this makes it draw more amps, but also produces more Watts of total power!

2. I believe the Wye wind is MUCH better for this type of application. It starts under a load better. I also believe it is more efficient, hence cooler running.

I did the test run on 15C 4000mah 4S configuration. I ran it hard and it lasted 25 minutes. This motor performs like the factory wind on 5S Lipo, but does it on 4S and starts better.

I will now proceed with the AXI 4130 rewind. I found a different brand 4130 6 turn Delta that's rated at 515kv. I'm thinking about 3 or 4 turn Wye termination should be just about right. :yes:

More on that as soon as my winding wire gets here. I believe the mail is pretty congested in some areas right now because of the holidays.

That is great news! Looks like I should be testing my crawler motors to a Y termination too.


As for the wind resistance, each wind will have lower resistance because of the larger amount of copper and lower wind. The phase resistance in comparison to a D termination would be higher of course. The combination of changing wind count, termination, and copper netted you better startups, better acceleration, and a higher top speed? I would say either your efficiency went up or your amp draw did, maybe both. Got any old data logging from the previous setup?

98% Efficiency is beautiful.... I want one... build me one...

Spin-up
 

I've been following this thread as I continue to experiment with my e-maxx. I'm starting to think that a centrifugal clutch might be just the answer. If the outrunner's only real problem is startup, why not let it "idle" like a nitro (just set your throttle trim up a little) and then just grab all the throttle you want to take off. If you can't really use the ESC brakes on a direct drive anyway then it seems like a natural fit, no?

Actually the esc brakes work fine on my redcat/axi setup. But the clutch idea would be nice. I am going to do a twin outrunner, twin hv85 setup. We will se how well the castle air controllers work!

With mixed throttle you could have variable braking or throttle from front to rear.

I have read on the Croco site and other sites, that you want the wind resistence to be as low as you can get it without resect to how many turns it is. That is a goal with motor winding.

Manufacturers make compromises at the cost of effeciency with motors. Small wire is used because it is easier to work with. The larger wire is harder to work with but produces a wind that has a greater Cross Sectional Area. Less Resistence. :yes: This Raises the Power Handling ability and efficiency.

I also feel like they steer away from the Wye wind because of the added termination point that can create problems if not done correctly.

They settled on a Delta termination, because in their testing with a prop, they are only measuring thrust at top speed and total amp draw.

They don't start the motor under a load at all compared to a Monster Truck. The amp draw doesn't come up hardly at all until some rpm's come on to the prop and make the load.

This makes the Delta wind easier and more profitable for them.

I have reached a point where I need a data logger. I have a brand new factory delta wind in the 3530. It would be VERY interesting, to collect some data from several runs with this custom wind. Then put the factory motor back in and collect some more data. Comparing that data would tell alot of things I'm sure. The difference is enough to see for sure. It performs alot better.

I put the factory wind on 6S one time and blew the transmission on the first run. I'm tempted to bump up to 5S on the custom wind, but I think that would be enough to make the transmission go Poof. I'll try to get some video soon.

The new E maxx should be hitting the market anytime. One of them has my name on it. I'll do this conversion with it. A transmission that can handle 2 1/2 times the torque of the original? Let's make that thing dance! LOL

How do we figure or gauge efficiency of a motor?

Huh? What do you want? Build you what? LOL

The problem with a clutch and this setup is, current clutch designs are up on the factory drive train where torque levels are much lower. How do we design a clutch that is inline with the shaft to handle the higher torque?

ESC brakes work fine with this setup. I've never had a problem with that aspect.

Hi Linc,

I'm very interested in what you're getting ready to do. Please keep us posted. We need pics. :yes:

If you can swing it, go with the HV110's. I've often thought about the Castle Controllers, but the lack of reverse and suitable brakes steered me away from them.

I believe with the mechanical brake setup that you have, they will do great! :yes:

If you really wanted a clutch that could handle the torque load, a modified baja 5b clutch should be able to hand an outrunner, it seems to cope with a weedeater motor in a 20lb truck!

Any specific reason to go with the hv110 over the hv85? Do you think that I will be able to pull more than 85 amps out of those outrunner with only half the load? It will be setup for an road running, so the rear motor should not have to work as hard, less weight transfer due to lower cg and stiffer, short travel shocks.

Well I'm not sure, depends on the setup. I am sure my Revo is spiking up more than 85 amps on take off. It performs much better with batteries that can deliver more current.

I like to over size in the ESC department if possible. You can't have one too large as far as ratings go.

That's going to be an awesome setup.:yes:

It should be pretty cool, would be better if this guy i know could custom wind my motors so that they have lwer internal resistance:wink::whistle:

I'll try the motors stock first and see how they perform. :tongue:

I received my fan yesterday for the redcat axi and plan to do some more testing, and a new chassis layout with more permanent mounting!:mdr:

Let me do some more testing, get some practice in and I'll consider doing a custom wind for you.

I intend to do a Wye wind on the 4130 for my Revo. Let's turn it up and see what happens. :lol:

My method of doing the Wye termination needs perfected also. In the 3530, I had to bring 3 groups of 7 - 22Ga. wires together. Solder a permanent connection, while having each of the 21 strands pulled tight. That's hard to do. This connection can't ever touch anything either, or an internal short will occur.

I'm thinking about using a miniature "hog ring". Slide the hog ring down onto the strands, pull each strand tight, then clamp the hog ring. At this point, cut the strands off with a dremel tool even with the top of the ring. Then cap the entire thing with solder. This connection would be small in size and alot better. The space to do all this in, is already pretty tight.

@JohnRob - Any thoughts or suggestions on the best way to do the Wye Termination?