ph2t

[ph2t]

thanks bithed! 🙂

just took it for it’s first spin and I’m very happy! the car really punches off on take off. I running the 12 tooth pinon that comes in the rtr kit.

On my old 4*2 stack of IRF7389 MOSFETs my car would stop pulling wheelies after 2-3 minutes. With Woah Nelly, I was still pulling wheelies after 10 minutes, no shit….

Woah Nelly connects straight to the battery pack, the wires are very think and low loss. I now notice that the batteries get quite warm, a lot warmer than usual. I guess this is the increased current flow (due to the really low loss MOSFETS) that’s causing the extra heat.

During this whole time, Nelly never went over 25deg celsius.

:approve:

ph2t.

[ph2t]

yup 🙂

I’ve run into a problem with the big pcb though. After putting the pcb into the circuit I only get 1.8V at the gate pin of the mosfets. This is too low to be able to turn them on properly :dead:. So unfortunately these fets won’t work. BUGGER!

I’m gonna try the large pcb on a daul cell, see if that’s enough input voltage to keep the drive on the gate pins sourced with enough current….

ph2t.

[ph2t]

yeah, I noticed this at the 1/10 track we went to recently. everyone was sporting foams……..

[ph2t]

look for a component on the PCB that smells basically.

look for grey/black discolouring and possibly physical damage to the part…

[ph2t]

Quote:

keep us posted.. wat i meant is a single in the new fets is less efficent than a single in the old fets?.. it only when u compare a double or triple in the new with a double or tripple in the olds… if u get my drift… i would love 2 get my hands on one of these “external turbos” … in other words will u be selling them

Edited by – merc-blue on 17 April 2004 12:30:01

Edited by – merc-blue on 17 April 2004 16:15:49

A single stack in the new fets is more efficient than the original fets. Theoretically it’s meant to be approx 20%. But, see betty’s comments, it is now proved to be better…..

The next “turbo” I’m making will have the performance of a tristack of fets. This PCB will be using different fets all together…

Here it is on the right of the pic. On the left is the current turbo PCB.

If all goes well I will be selling BOTH.

ph2t.

[ph2t]

HAPPY BERFDAY!

:smiley16::smiley16::smiley16::smiley16::smiley16::smiley16:

[ph2t]

cool, I wants to see pics…….

[ph2t]

you bloody fool!

I love it!

:p

[ph2t]

those fatty pullback rims on the front really suit this car….

[ph2t]

A single stack is more efficient than stock BUT not as efficient as a double or triple stack of fets….. It’s all about how far you want to go.

I’ve noticed that my tri-stack car with the insanely low gearing (3.95:1) is still a great car to play with and it’s top speed is insane for a single cell.

I’ll try the single fet mod on the 3.95:1 gears today and let you know what the differences are……

ph2t.

[ph2t]

Quote:

damn…u made the car look like a MiniZ wannabe. lol, but that’s a good discovery. the external turbo looks cool. so i guess a Tutorial Comin soon?

Tutorial? Dude, it’s pretty much just the mosfet mod using different mosfets. Since they aren’t pin for pin compatible with the original transistors I made a pcb for ’em….That’s it….

Quote:

How fast is too fast? and how long until you start buring out motors in 30 seconds?

You can never be too fast. No motors will burn out on a single cell…..

ph2t.

[ph2t]

Quote:

Looks like a killer performance! I wanna do this mod. Can you please make a bigger pic or small diagram on how to exactly hook these mosfets to the PCB? It will save a lot of time answering all kinds of questions…:D
Thanx!:)

Hey jevries, welcome to the boards…. 🙂

I’m not sure what you want to know exactly? Do you want the fet PCB diagram? The layout for the fet PCB? OR do you want pics of where the wires FROM the fet PCB goto on the Bit PCB….?

This is the circuit schematic, it’s an old one I made a year ago, so the fets are labled as the IRLML2502 ones, but that doesn’t matter, fets are fets… 🙂

I used CircuitMaker 2000 to make the PCB and then I printed it (in negative format) onto transparency film.

I then processed this onto pcb and etched from there.

:p

ph2t.

[ph2t]

lol dude, that was one fucked up film…..

[ph2t]

nice work man, do what z says, the grill effect will look great! what putty are you using?

cheers,

ph2t.

[ph2t]

if you can find any cheep clones dude, pick ’em up. Some clones have some really low ratio’d gearing…

Whatever you do, if you’re gonna go low ratio/high top speed then make sure you’ve got the torque to pull it off…

ph2t.

[ph2t]

you look really happy man, congrats!

ph2t.

[ph2t]

Well here’s some more video. This footage is of Leon’s hopped up Z. It’s running pretty darn smooth with a heap of option parts and an external turbo along with leon’s (own?) handwound rotor…..

http://users.tpg.com.au/ph2t/leon_z.avi

Divx, 1MB.

Sorry but the videos are sorta missing a soundtrack these days due to lack of space on my ISP account. Hopefully the new features of having online member’s space (hint, hint…:p) will happen soon……

ph2t.

[ph2t]

Here’s some more video of my Madforce and Jamie’s Z. This was shot on Leon’s digicam.
This is a cool little clip showing the huge speed differences between the Madforce and the MR-01.

http://users.tpg.com.au/ph2t/z_stuff.avi

Divx, 500KB.

Enjoy! :approve:

ph2t.

[ph2t]

yeah , unfortuately my madfoce died an early death thank sot hitting betty’s ramps at 30+ kph.

Here’s some video of Jamie’s Z in action. Talk about fast, sheesh!!!

http://users.tpg.com.au/ph2t/jamie_z.avi

4MB, divx format.

Enjoy!

ph2t.

[ph2t]

done dude, already in the car!

so we have access to power points?

and what are you bringing? leon has told us that there will be some 1/10 pukes there…

I’m picking up betty and jamie, we’ll be there at approx 11:15am….

ph2t.

[ph2t]

looks are looks! it’s the performance that matters…….:D

ph2t.

[ph2t]

looks are looks! it’s the performance that matters…….:D

ph2t.

[ph2t]

Quote:

Sorry PB, I’m tied up in a few other things and wont be able to make it.
:sad:uA

damn dude, it won’t be the same. WE’ve never had a meet without ol’ micro………..
:dead:
ph2t.

[ph2t]

Now that you explain it that way dude, it make perfect sense…..

Hopefully there won’t be next time……..

ph2t.

[ph2t]

well the last frying episode was an attempt at 6 cells…… I dunno what happened something must of short ’cause as soon as I turned the power on (no motor in cct) the fets started to fry….

Some things I have found out though:

1) The circuit is always on with respect to the drivetrain h-bridge & steering h-bridge. The Source pins on the p-chan fets in both h-bridges are connected directly to Vcc.

2) The battery Vcc rail is switched AFTER the connection to the two h-bridges. Therefore the whole circuit turns off except for the p-chan fets in both h-bridges. (this makes sense since my first fet frying incident continued to fry even after turning the power switch off)

3) Once fets overheat they short out. So even if you keep turning the PCB off and let it cool, you’re still gonna have problems…..

4) I believe that the safest way to do a 6 cell mod is to use a 5V regulator (or a LM317T to regulate at 4.8V for those anal techies out there….. :)) and just power the main circuit with this. I think one should power the steering this way as well jsut to be safe. That requires you to cut the PCB track going to the Source pins on the p-chan fets in the steering h-bridge to isolate them from the drivetrain h-bridge…..

My heads gonna burst, gotta get back to making my madforce just work!

ph2t.

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