upgraded FETs

[scatmanjohn01]

what would having two strands of wire being wound do?

[Rez]

Neuro, Digikey lists several 4905 and 3705 products, each with various suffixes. I don't see any mention about which ones are "logic grade" and which ones aren't. Help me out?

[hostyle]

Ok, so after reading all these posts and thinking I have grasped all this, I have one question:

Neuro, do you remove each set of FET's on both sides of the board?

[Rez]

Originally posted by hostyle
Ok, so after reading all these posts and thinking I have grasped all this, I have one question:

Neuro, do you remove each set of FET's on both sides of the board?

I believe the FETs on the top of the board are for the steering servo.

[hostyle]

OIC, ok thanks

im new to this stuff....i would really like to see how to upgrade fets so that i can run 6 cells, and a sb motor....and i want to do a wire upgrade...can some one tell me or post pics on how to make that work so i dont fry anything....if u want u can email me at MAKINMOVES84@AOL.COM

[hostyle]

If you take the time and read through this whole post, it goes into very deep detail, and give detailed schematics.

[xxspeednplayaxx]

fets - hard to explain, you buy the fets listed somewhere in this thread, and replace your current fets (found under the board) with two of each new fets.. another way is to do some fancy wireing (neuro explain on page 10-12 which give a super amount of current capacity..

6 cells (7.2V) - you buy a double aaa holder from the shack and wire it between the two batt packs found on the car (its the long black wire).. or you can buy two lipoly batts and get the same results

spinbrush - go to a store that sells toothbrushes, and get the spin brush tooth brush, beak it open and get its motor, pop the end cap off (white thingy with solder points) then pull out the armature (thingy in the center) then replace this with the armature from your S2 motors (you may wish to remove 5-10 windings (wires around the motor) any more than 10 and you wont accel good, then put on the s2 end cap... basicly the spinbrush motor has good magnets, and a good can, everything else should be from your s2 motor

wire upgrade - DONT BUY ONE THEIR A RIP OFF.. just go to the shack and get a spool of thick wire (not to thick) im not sure of the guage so just find a wire size you like.. all you have to do is one by one de solder your stock wires and replace with the wires you got...

happy modding!

[ninja828]

Originally posted by xxspeednplayaxx
wire upgrade - DONT BUY ONE THEIR A RIP OFF.. just go to the shack and get a spool of thick wire (not to thick) im not sure of the guage so just find a wire size you like.. all you have to do is one by one de solder your stock wires and replace with the wires you got...

and make sure its STRANDED wire, not solid...otherwise you'll have too much resistance in your wires and could ruin your xmod that way......i actually am still trying to solder on the 16 gauge wire i have as a replacement for the stock wires but im one hell of a hard time w/ that....maybe i need better quality solder....

oh, and does anyone know a good site to order the IRF4905 fets that DOESN'T require a credit card? i've already tried digikey, but they're backordered and i wouldn't be able to get them till march 4th....

[xxspeednplayaxx]

hold up standed is like many many little stands... wow thnx for telling me, i was gunna use 20 guage of the soldid core wire, its what i used for my lights.... hmm i have a bunch of 18 guage threaded wire that should work..

[geofroley]

Nuero what kind of FETs would you recommend for a 35 turn or lower application?

[neurokinetik]

Originally posted by geofroley
Nuero what kind of FETs would you recommend for a 35 turn or lower application?

Right now, there are only four options that I am aware of.

Option 1: Stack stock XMods FETs. We don't know what they can really do yet, but they do seem to be better than the stock Mini-Z FETs. Disadvantage: Limit of double stack before chassis modification needed.

Option 2: Stack IRF7389s. Proven chip, it works. Has the same disadvantage as stacking the stock FETs.

Option 3: Stack Sy4562s. Again, proven chips. Has the same disadvantage as stacking the stock FETs.

Option 4: Build my discrete FET setup. Handles more power than all but the biggest stacks, and the ability to add heatsinks to increase the power handling is another plus. A regulator could be added to the circuit which would allow for pretty much any battery combo you care to try, while keeping the stock electronics at a safe 5V. Disadvantages are finding a place to mount the board, and also routing the extra wiring.

In my Mini-Z, I am running a 3x2 stack of IRF7389s, and that is runnning a 35 turn motor with Neos. With that setup, the car is just too fast for the course I run it on. It is fun to watch, though, as I run around at about 20-30% throttle, staying with all my competitors until I feel like passing. Then a quick blip of the throttle sends me by them like they aren't even moving. :lol:

My discrete setup is only in my test chassis right now, as I want to see if I can shrink the board down even a little smaller than it is now.

[geofroley]

Hmmmm. . .Got a tutorial on your FET mod?

[ninja828]

just look at the previous pages. there should be more than enough info to build neuro's fet mod

[xxspeednplayaxx]

yup this thread seems to have a alota info (just gotta read)