I am not surprised by the useless cells you used on your hvmaxx!!!!

are they updated with the sintered rotor? i guess not?

I'll shoot a movie of my hvmaxx 4400 powered maxx on 4S lipo.. You will be surprised.



@griffinru;

Thanks for the write-up.!

Man, you make it look so easy. As for motor choices... well, there are plenty of better, more powerful & more efficient ones that could work with the HvMaxx esc via your clever mod (I've read that several times- impressive doesnt come close to describing it). I just feel that I like the sensored smoothness of the HvMaxx esc, so if there was a way to improve its amp handling capabilites -IE: so you could use two motors as I described, then that would be a rather nice route to try; the HvMaxx motors are only about $110 or so, which isnt too bad. I'd like to see the video Serum, you've got me all excited and interested!....

You Welcome, Rene!

It won't be cheap to double current capacity of HV-MAXX ESC, but you can try to increase heatsinks surface area by replacing stock heatsinks with something custom (Just make sure not to short them).

Have you tried VXL ESC with sensored motor?
And I'm pretty sure Feigao has a 60A sensored car controller.

Interesting ideas. If only the VXL esc was 4s and not 3s, I would jump at it! Hopefully traxxas will bring out a higher voltage esc sooner or later, then I could run almost any sensored & sensorles motors (within reason). Hurry up traxxas.

EDIT: Is this you?

http://forum.rcdesign.ru/uploads/photo-4415.jpg

I dunno what I was expecting, but... that wasnt it! :lol: :wink:

Very nice Artur! (you do make it look easy having done a little modding myself now) I see you are using the 3rd generation MM boards, any problems running 6S? I seem to remember some guys having problems going above 4S, someone said they thought it was voltage protection for the new fet's...

Also on the new fet's do you have a link to the fet spec's? I've seen the part number but I can't seem to find the specific fet.

I know with the lower fet count there appearse to be "open" spots for fet's, any chance one could add the extra 8 fet's to each board and esentially be tripling the capacity?

Lastly do you think it would work to do the extended buss/dual heatsink setup like I did with mine while using doubled up power boards? (mine is working GREAT and actually feels colder than ambient after a good hard run- of course I'm running a very light load setup with the XXXT/5700KV 2S lipo)

P.S. I found carefully using a wire gauge drill bit the same size as the 22awg buss wires to "clean out" the pcb holes made assembly much easier.

Will post pic's of my completed mod as soon as I find out what you guys are using to post your HUGE pic's (wink,wink, what service /how do you do that???)

Photobucket works great for fairly large pictures upto 1024 x 768 and its free. Just take your pictures and tranfer them to your PC/laptop, save them as a .jpeg file, then after signing upto photobucket upload the pictures. It allows you to specify a maximum size/resolution so you can either post normal sized pictures directly onto the forums (copy and paste image code which is below pictures), or you can post a link to a much large picture in your photobucket album. Piece of cake really.

here goes...
esc befor all the assembly.
http://i217.photobucket.com/albums/c...now65/esc4.jpg

A pic of the completed esc before shrinkwrap, it is 90x32x32mm, went with mounting the caps inline with the power board to ensure unrestricted air flow, makes it 20mm longer... might use 6 smaller caps mounted 90' to the power board like originals if I find this too long for the other cars it will go into.
http://i217.photobucket.com/albums/c...now65/esc1.jpg

You can see the front fan better in this photo (note, far right, the 18awg red and black wires are power to the fans, the silver wire is the shielded throttle signal wire from the reciever -deleted the red+black power and ground wires, and you can see the esc power switch and 24awg wires-twisted ones at top)
http://i217.photobucket.com/albums/c...now65/esc3.jpg

Here is a view of the "brain side" you can see the caps and extended buss wires better in this pic (note, I heatsinked the fet drivers and the esc's bec circuit which I understand still powers the esc "brains") and the unit is mounted to a thin piece of brass on the bottom to make it easier to keep everything intact while the heatshrink goes on.
http://i217.photobucket.com/albums/c...now65/esc2.jpg

Last photo is with the esc temporarily wrapped in electrical tape mounted in my XXXT untill my heatshrink shows up. So pleased it is still alive after doing all the soldering work to it :) :) :) (you can see the led's good when it's not wrapped in black electrical tape)
http://i217.photobucket.com/albums/c...now65/car1.jpg

I have also rewired the CC BEC, reciever, and steering servo with isolated 18awg power wires (with caps on each leg) and shielded signal wires, that are not shown in this photo.

VERY interesting thread guys!

But just a quick question: How do you remove you MM heat sink the best way? You seems to have done it a couple of time.

It was 2 stock hv 4400's.(stock rotor)

I actually have my hv-maxx in my crt.5ext now with 4s lipo. I have it geared high(50mph using the lowest hardened pinion I have), but my MM/10L on 4s has much better acceleration and mid-range power; the hv-maxx is much much smoother though, a more pleasurable driving experience.

@ griffinru,

how would I go about putting the sensor from the hv-maxx on my feigao 10L, if it is possible? My hv-maxx is much smoother then my MM/10L setup. I feel it is better for racing. The hv-maxx just doesn't have the power I'm looking for....

Thanks! :mdr:

Heatsink was never properly attached on mine (there was a little resistor under one of the fet's that kept it from sitting flush) that was the prompt for my modding... Have read about heating, freezing, and good ole manual labor. Seems to me that the thermal epoxy gets softer with the esc hot, no matter what you do it seems CAFREFULLY working a thin razor blade between the heatsink and fet's is the thing to do.

I'd wait for a reply from Artur, Steve, or lincpimp though ;)

Sorry for Delay...

Nice job DrKnow65, creative and open minded!

If you do not want to use slave configuration, then it would be a little bit painful. Old generation Feigao motors, with thinner end cap would be almost impossible, unless you made a custom end-cap. Then you need to add sensors, i.e custom pcb with hall sensors... If you can do all this, then yes it is possible. Otherwise use slave configuration or order from Feigao sensored version.

Heatgun and a razor blade.

Ok, thanks. I thought it might be possible to remove the sensor/endcap from the HV-maxx motor, it looks like its much more trouble than its worth.

Thanks again!

Bye :mdr:

Take a look at this....

http://www.teamnovak.com/password/no...nbgr_560px.jpg
Thats the rear endbell of a hvmaxx motor, I think its specifically designed for the 380 sized magnet of the 2 pole motor.

Wow, seems like a lot of extra room for nothing.

Agreed. Its made me think a little bit (run for cover!)- the hvmaxx motor is about 70mm long, yet the sensors and end bell take up so much room, that the magnet only actually measures 45mm long x 14mm diameter. Anyone care to compare their feigao L and XL magnets if they have some motors laying around? My theory is a 380 XL motor would be just as powerful as the hvmaxx, and run about the same temp in a sensible size/weight/geared vehicle. And be a damn sight cheaper to boot if coupled with a suitable esc on 4s/ 12 cells.....

Here are some pics:

http://www.rcpics.net/view_single.php?medid=85850
http://www.rcpics.net/view_single.php?medid=85849

Hmmmmmm. It looks like its just a smaller diameter- that giant silver motor, is that 72mm long, or is it longer than a normal feigao type XL motor ( it looks a lot longer )?

The big one is like the Great Planes Ammo 36-88-1280 http://www3.towerhobbies.com/cgi-bin...?&I=LXLXA1&P=7 and it is 88mm long. It is a beast of a motor and I punished 2 of them and I'm saving the third for something mild. The first one I tried with 36 volts and it lasted longer then I thought. The second one I kind of shorted with a mounting screw that was just a tad longer. They have the strongest magnets I've seen in a brushless motor.

Cool. Shame they only have the one kv rating for that size, otherwise one would need a hv plane or boat esc to run it properly. The Kb45s look great too, but they are out of stock everywhere pretty much, and the odd shaft size/ mounting pattern is a draw back. Weird, I was thinking last night about a cheap forward/brakes Bl setup using a cheap BL motor and esc, just for a bit of fununtil something decent comes along; just as I get motivated enough to want to try this out, eveywhere is out of stock of good cheap motors.... its a conspiracy I tells ye...

Try one of this:

http://www.hobbycity.com/hobbycity/s...idProduct=5422
http://www.hobbycity.com/hobbycity/s...idProduct=5421
http://www.hobbycity.com/hobbycity/s...idProduct=5420

They are like the Align 600L, but cheaper.

But much cheaper. Im liking those- about £25 for a motor more than twice as powerful as a hvmaxx... What are your thoughts/experience of them- I think the 2000kv item looks right for my needs, maybe on 14 cells? I will haveto get some 5mm bore pinions, and have a poke with the gearing calculator...

EDIT: I wouldnt be against trying some normal or other hybrid outrunners either, I just dont have that much experience with calcualting which ones have enough torque for my application. Since Im using the old gmaxx style motor mount, motor diameter is not a limiting factor- I can always fab up a new motor mount part if it is larger than 25mm spacing for the mounting screws. Only thing to bear in mind is that I have 6 sets 7 cell packs, so the kv/voltage range of the motor & esc could be a potential issue sometimes.

I ran an Align 600L with 36 volts, which is way more then they were supposed to ever see. I like that fact that they have a lot of torque and you can use that in your favor. When I get my chassis design fully finished, I'll get a motor simular in design, but made to work with 36 volts and they are bigger then the Align 600.

WOW, I am impressed with the knowledge on this site. I am a hardcore newb with BL, but have ben in the hobby for years yet in has been a decade since I have had an electric (no such thing as BL back then). I am buying a Mamba Max and doing the stage one mod myself. I am an engineer and cannot leave anything alone, I was planning on adding better caps, but it is great with the step by step information on here on help you with disassemby and reassembly. This is great to see people not going out and trying to fix it with more money, but with knowledge and research.

Just ordered a Mamba Max now i'm going to do the stage 1 mod! I ordered everything except for the Zener TVS diode because I couldn't find any singles and didn't want to pay $6 + shipping at Digikey for 10 when I only need 1.

So does anyone have any extra Zener TVS diodes that they would be willing to sell to me? Is there somewhere else that I could get one for a reasonable price?

These are surface mount 1500W and 27V. Link to Digikey: http://www.digikey.com/scripts/DkSea...C27AT3GOSCT-ND

Thanks!

What is the point of these Zener diodes? What is there function, and exactly how do you solder these things to the board? Thx!

I believe they are refered to as 'voltage clamps', and the purpose is to absorb transient voltage spikes that might harm the cap or batteries... something like that I think i read a while back...

They are surface mounted normally, so good soldering skills and a good iron are required.

I believe suicideniel is correct about the "clamp" function. I just soldered mine to the back side of the power board where the battery leads poke out.

<TABLE class=tborder style="BORDER-TOP-WIDTH: 0px" cellSpacing=1 cellPadding=6 width="100%" align=center border=0><TBODY><TR><TD class=thead>04.16.2008 07:24 PM</TD></TR><TR title="Post 163814" vAlign=top><TD class=alt1 align=left>DrKnow65</TD></TR><TR><TD class=alt2 align=left>I believe suicideniel is correct about the "clamp" function. I just soldered mine to the back side of the power board where the battery leads poke out.</TD></TR><TR><TD class=thead>04.16.2008 07:01 PM</TD></TR><TR title="Post 163811" vAlign=top><TD class=alt1 align=left>suicideneil</TD></TR><TR><TD class=alt2 align=left>I believe they are refered to as 'voltage clamps', and the purpose is to absorb transient voltage spikes that might harm the cap or batteries... something like that I think i read a while back...

They are surface mounted normally, so good soldering skills and a good iron are required.</TD></TR></TBODY></TABLE>

- Just to add for the comments above
Zeners/Transorbs voltage was selected to protect FET's from voltage spikes, running at 4-5S close to FET's rated voltage and for caps. With temp going up caps rated voltage goes down as well over the time, so to keep them happy I installed zener.

And as bonus reverse polarity protection for FET's, not for wires and bad soldering :)
DO NOT CHECK it!

Are these diodes polarized? I have some and there's no indicators on them to suggest there's a positive and negative side. Thanks!

Yes they are, I'll have to remember which way to put it on but thewre is a little C shaped notch in one side of the top of the diode...

Notch goes to the positive side.

cool, thx

ARTUR do you have any plans on putting 2 Monter mamba's to make a super controller :lol:.

Does having the booster cap on those long leads decrease the effectiveness? Or is it ok so long as the wire guage is low enough to keep inductance down (something like that)?

Yes,
The shorter the current loop the better, but you need to find a good place for cap as well. It is a trade off, but still improvement over long leads, connectors and such