RC Jet Car: SR72 "Woodbird" made with server fans (PWJ54)

This time I'm really playing because it's nice weather. And everything was made from scrap parts, even the RC was given to me. The only new part was the battery and one servo which I did then.... but watch the video!
The turbines are fans from a HP C7000 Blade enclosure. 200W each.

[@artisankatstudios7902]

Great re-use of those fans and great idea!

[@tad2021]

I had been wondering why some of the fans had different wiring to the motors. Know I now, thanks. Also cool use for those things. I think anyone that's delt with C7000s has a small pile of these sitting around.

[@barryg41]

cool little rc!!

[@TeRniZek]

Wow great video!

[@user-ft4jy9sw2m]

Nice car!)

[@scudsturm1]

ahh, the childs in your neighbourhood can definitely hear this thing

[@gamerpaddy]

saw those turbines on banggood recently, didnt know they come from hp fan modules. interessting.

[@PlaywithJunk]

Yeah, they are selling it as "electric turbos" for your car... how silly is that! But you get them for $5 or so. I guess they took it from the scrapyard.

[@gamerpaddy]

i mean those exact turbines which they must have taken out the hp supplies. www.banggood.com/de/DC-7_4-16_8V-52000RPM-Three-Phase-Inner-Rotor-Brushless-Motor-p-1084192.html but in the end, slightly more expensive than just buying those used fan modules off ebay. edit: habs auf Englisch wohl missverstanden. Ja, Die haben die Lüfter bestimmt irgendwo rausgeschraubt. Auf ebay und co fand ich jetzt auch welche für 5...10€ das stück. ich dachte du meinst diese "elektronischen turbo" mist den man in den Luftfilterschlauch hängt haha.

[@PlaywithJunk]

Ich meinte das hier: www.yoycart.com/seller/ming9681/ "Car turbo" :-)

[@jolesco]

I like the name "SR72" the predecessor to "SR71" Blackbird :)

[@PlaywithJunk]

That was the idea....

[@allobject]

1:35 - LOOOOOL

[@erikjgreen]

One more thing - your car might go faster if you remove the stator vanes from these fans. The vanes are molded in to the can, and serve to turn part of the energy of the air the fan moves to increased static pressure for flow through cooling. Since they're taking away part of the energy of the air flow for this purpose, if you remove the stator vanes you should get more speed?

[@PlaywithJunk]

The sators are there to direct the airflow into a linear motion. If I remove the stators the air would exit in a more circular motion, a vortex and I doubt that this would increase thrust. But there is anoter problem: The stator is part of the motor mounting. Removing them would be difficult...

[@FrancescoF]

Great video! Can you better explain how to modify them to run out of the server? I'll probably pick a couple of them for some projects I have in mind

[@PlaywithJunk]

Put the two jumpers in as in the pictures. Attach +12V (as on the picture) and GND on the other side of the connector (the big golden pad). Take a power supply that can deliver 15 Amps and there you go.

[@FrancescoF]

Play with Junk thanks!, so I only need to short two contacts on the connector and connect a resistor to ground, great! Is it possibile to control them with an Arduino?

[@PlaywithJunk]

You don't need a resistor, just a piece of wire. Look at 1:51, the green wire goes from GND to the point you see in the photo ( 7:12 ) I use it only in ON/OFF mode... you would need a relais (20Amp). Maybe the newer vesion with an attached RC motor controller could be managed with an Arduino. (PWM control)

[@djangoryffel5135]

komisch, hab die Glocke bei dir drin, aber hats mir nicht gemeldet... Nice dad Teil. Wie schnell ist es etwa gefahren? Ich mein sieht noch recbt fein aus, klar kein RC Car Niveau, aber hinterherrennen wäre wohl hoffnungslos, oder? Wie siehts bei den Fans eigentlich wegen Effizienz aus? Welche sind besser? Ich würde ja mal vermuten, die neuen sind im Bereich gesamten Bereich etwas effizienter, aber nach obrn hin wirds schmall. Aber macht sich das überhaupt bemerkbar?

[@erikjgreen]

I'm playing with a set of these fans now... do you know which pin/connection is likely a PWM input? I was thinking the PIC pin 9 was a candidate. I tried to find out how the fans communicate with the OA controller to speed control them that way, but I couldn't find documentation. I did find the firmware for the fans, but there's nothing obvious in the disassembly listing.

[@PlaywithJunk]

I think it's easier to connect the motor (the newer type) directly to an RC motor controller.

[@gamerpaddy]

Bought some because this video. got 2 new and 2 old modules. quick overview: Newer 12v version: ML4425CS BLCD motor controller media.digikey.com/pdf/Data%20Sheets/Fairchild%20PDFs/ML4425.pdf AJ29AU mosfets all N-Ch(?) HA4315I/SS022 unknown part, could be a PIC for bus communication and speed control NE555 classic lol Old 48V version: ML4425CS BLCD motor controller media.digikey.com/pdf/Data%20Sheets/Fairchild%20PDFs/ML4425.pdf 3055E and J634 Mosfets (N & P Ch.) no datasheet found PIC16F88 could be bus communication and speed control ww1.microchip.com/downloads/en/DeviceDoc/30487D.pdf HC123M, Dual retriggerable monostable multivibrator. www.ti.com/lit/ds/symlink/cd74hc123.pdf ISL6115 Power distribution controller

[@labrat810]

Any way to PWM-control the HP-integrated ESC? I'm looking to re-use these in a PC controlled by motherboard's PWM (6-Pin power'd. RPM sense would be nice too).

[@PlaywithJunk]

There is certainly a way to do that because that's exactly what happens inside the HP Blade chassis. But I didn't find any information about that protocol.... Using the low voltage fan version with a cheap ESC is much easier.

[@bobbykannady1180]

how did you power the motherboard? I tried to wire the motor tight to speed controller and it turned very slowly. on you second motherboard picture you have "pic pin 9" what does that mean. You also have jumper to ground. I have limited knowledge... can you help me out? I'm trying to use the motor for my son's 4th grade science project. when I ordered I was hoping for 12 volt motor.

[@demkolem7594]

I get 4.5A, why? 7:13 which gives this connection? PIC pin9 to be unconnected?

[@PlaywithJunk]

No, you connect PIC pin9 to GND with a jumper wire. That will turn on the fan at full speed. Without this connection your fan runs at low power.

[@elektroundco.8384]

Do I need a jumper for the new version?

[@thanismurugathas2929]

Any idea why my HPC700 fan is beeping? I have a 3S power supply and a 30A ESC and it just keeps beeping at me

[@PlaywithJunk]

Do you mean a HP C7000? The motor can not beep. It must come from the ESC that wants to tell you something. Is it possible that you got a high voltage fan? There are two versions. The older has a motor running at 50V and the newer has a 12V motor. You can identify them by the motor cables. The old has thin cables with a black heat shrink tube around while the new (12V) has thicker wires in red blue and yellow visible. The old PCB has a large heatsink with DC/DC converters (to make 50V). You need a new version to run on 3S battery.

[@thanismurugathas2929]

​@@PlaywithJunk Thank you very much for your response!!! I definitely have the 12V one as described in your video (the new one), and I'm running it on a 3S (11.1v) battery ( 5200mAh ) via an ESC that says 30A on it (very sorry if the information isn't very good I only just started learning about hardware mechatronics). And after some testing, I can definitely say it is something within the fan unit itself that is causing the beeping, not my ESC. But I will try to look into it (and I've seen people try to power this with a 12V car battery so I'll look into that in the future) and let you know if I make any progress. A big thank you for being so willing to help me and giving me such a lengthy response!

[@PlaywithJunk]

Hmmm... maybe time to consult the ESC manual. Do you have another ESC to try? Maybe it's faulty...

[@thanismurugathas2929]

@@PlaywithJunk Yes, just purchased a new ESC, so I will look into that! Thank you!!

[@PlaywithJunk]

@@thanismurugathas2929 OK... Maybe I was just lucky but I bought a cheap 20A ESC, connected it and it worked without any issue. 🙂

[@DoogieLabs]

I have been working on a high performance RC hovercraft that uses these fans. Been working on it about a year now, and will be taking orders soon for those who want their own. I was able to carry more than 70lbs with it! /watch?v=uT6DqMOunaU .. There are several videos that detail the construction and design of it. These fans are great fun!

[@DoogieLabs]

Also: doogielabs.com/high-performance-rc-hovercraft/ www.gofundme.com/hovernaught

[@dragan3290]

These are being sold as supercharger on ebay.

[@PlaywithJunk]

I know, but that does not work...

[@aniketkedar6545]

Hello, Great video,tried the jumpers you gave at the end of the video,have the same model,but couldn't get it to work.The fan starts rises to it's max then stops suddenly,the power supply is beefy about 12v @ 40A,so this is not a problem

[@aniketkedar6545]

I didn't get the PIC Pin9 jumper,can you be more specific,just a small help, and it will ease up my work. Thanks in advance.

[@PlaywithJunk]

I had the same problem when the voltage dropped below 10V. Have you measured the voltage directly at the fan module? Maybe you used too small wires? The PIC pin9 is tied to ground. You can use any ground point you find on the PCB.

[@aniketkedar6545]

Yes you are correct,at about 10.2V the fan shuts off,used thin wires,but in the pinout you have shown,the yellow circle is tied to pin8 of PIC,please confirm

[@PlaywithJunk]

It may be a bit confusing. The circle above IS pin9, it's part of a track to pin9. This must be connected to ground.

[@reecebeck971]

@@PlaywithJunk How are you controlling the speed of the fans?

[@Spirit532]

Those aren't real jets though :( That would be much nicer, but extremely expensive. The cheapest jets are around $1200 and have a 10 hour full rebuild/maintenance cycle :( Absolutely ghetto engine switch and brakes, though.

[@PlaywithJunk]

That was the closest thing to a jet I could get. And at no cost!

[@CountDuckula07]

If companies can sell jet skis, Play with Junk can make RC Jet cars with ducted server fans :)

[@PlaywithJunk]

Right... it has no jet and it is far away from a ski.

[@TANMAN9095]

jet my ass

[@tienta8362]

Black bird cad

[@PlaywithJunk]

that's why I call it the Woodbird :-)