what fan for feigao and heatsink/clamp
 

Hi guy's, I want to try and strap a fan to my 8xl with rcm heatsink/clamp and don't know what fan to use. Something bigger than the one on my mm and can handle 14.8volts. After ten minutes my motor temps are still hitting 185 deg (even with low gearing). I run a 4s 6000 pack and I'm forced to shut down before the runs over. Anyway if anyone has a fan in mind or has one on their set up please lmk thanks.

A 30-40mm 12v fan would be perfect to run on 14.8v- try ebay or some PC modding websites.

Thanks suicideneil I will look into it. Ps love the website we have alot in common I think. FTW

http://www.newegg.com/Store/SubCateg...name=Case-Fans

Lots of choices there. ;)

If you don't feel comfortable running a 12v fan at 14.8v, you could either use a linear 12v regulator, or just use 2 or 3 diodes in series with the + lead. The v drop of each diode is around 0.7v. Three of them would bring 14.8v down to 12.7v.

However 12v fans running on 14.8v is fine IMO. You might shorten the life a little, but I think the dust and vibration will kill it far sooner than slight overvolting will.

I thought fans were evil?..

Im tempted to use some myself with my new motor when it arrives, just incase it trys to BBQ itself like the last one did; I opened it up, and it smelt like tobacco inside!

i run a 12v fan off my main 5s pack it hasnt burned out yet

Cool guy's I just ordered a 40mm fan (actually it was a six pack of them) and will have one zip tied to the heatsink asap! I would love to see my temps come down 20deg.

report back here when you install the fans...

Ok Ill let you guy's know what it does....o yea and thanks for the link bensf those fans are wicked cool but bigger than an irish broads ass!

Fans ARE evil, but if you must run them...

oh jeez, here we go, brian on a fan rant :lol:

I just got my 6 pack of 40mm 12volt fans and bolted one to the chassis guard next to the motor and ran the piss out of it. On 14.8 volts it blows harder than an out of work porn queen on crack and dropped my motor temps from 185 to 155 and did it on a hot day (around 80 deg). My run times are 23 minutes (at race pace) the the motor hits 155 deg's after about 6-8 minutes and stayed at that temp throughout the whole run. I only have one chinese motor and will not run it again without a fan. Heres a pic of the install. http://s283.photobucket.com/albums/k...riedfatnhorny/

I bet you can hear it over the truck when it's close! :lol:

Yes I can hear it, from about 3-4 feet away when I'm barely on the throttle not bad at all. I can put my hand over the cut out in the body where the engine head stuck out and feel the hot air blow out...the fan is worth every penny!

since you bought a 6 pack would you be willing to sell me one or two? Or do you have other projects for the rest of them

Sure pm me.

How much did you pay for the 6 pack?

16.50 free shipping! Ebay item # 200246434167 SIX NEW MINI BRUSHLESS 12 VOLT DC COOLING FANS QUIET

For some reason I cant reply to any pm's..when I click reply it won't load the page. Anyway thats why I posted the ebay listing.

so howd you hook up the fan for power? the only fans ive ever installed was the mmm fan which plugs into the circuit board.

Just solder the fan leads right to the power leads on the control or solder them to the esc's connector.

Anyone trying to reach me should send me an email cause I can't reply to pm's...I click reply and the page won't load.

why are fans evil? i hear this hear and there, but they never explain why. ive never installed any fans on any of my rc's and ive been in the hobby for over 15 years. only fan ive ever installed and had was the one in my MMM. i would like to get some opinions first before i install the exact same fan as cool runnings onto the esc power lead. i dont want it ruining my mmm if thats why they're evil....

They're evil when you depend on them and they die. If you have a fan on your ESC or motor to keep temps in check that's fine. But when the fan dies and you don't know it your motor or ESC may die too

ouuu is that the reason ...hahah makes sense tho. but if thats the case, im not gonna be too worried about that then. i thought it was because there have been many reported failures to the batteries or esc or reciever from hooking up a fan.
so i install it "Just by soldering the fan leads right to the power leads on the control or solder them to the esc's connector" as coolrunning stated.??
isnt that the same thing? or did he mean the esc connector the reciever connector.
whats the safest and easiest way to power the fan. i was hoping to just have it plugged into my reciever but the plugs are different.

Fans are not evil at all and they wont hurt anything at all they draw their power from the battery. Also this was not an absolute necessity for me I just feel alot better about running at 150 versus 185 (I demagnatized a nemesis 7xl at 200deg) If your running so hot that a fan failing half way through a run destroyes your motor...you have set up issues. A fan is just for keeping temps low and extending the life of your motor or control. I doubt their's a single soul on these forums that would rather run at 190 versus 160. The air blowing from this fan blows directly at the heat sink and blows under it and over it right at the side of my esc lowering its temps another 5-10 deg I swear!

but now the other question is, is it safe to just ziptie the fan onto my rcm motorclamp/heatsink? or will the heatsink get so hot it may melt the plastic to the fan? what if i put washers inbetween the two. or will the washers still get too hot and still melt the fan?
oh coolrunnings, if its not too much trouble would you be able to take a picture of where you soldered the fan leads. just to be sure so i dont solder at the wrong place.

thanks

Yea sure I'll email one to ya. Theres two spots I like one of course is right to the deans connector on the esc,as soon as you plug in the speedo the fan starts humming...the other spot which is where I'm soldered to right now is the solder tabs on the mm control (you know the tabs you solder your power wires right to, that's it. O wait a minute you have the mmm right? Theirs no solder tabs on that one, just solder it right to the deans on your esc bro. What are your motor temps?

yea i have the mmm. i running 2 lipos so on the mmm power leads, i have a wire going from + to -, and - to - , and + to + on the dean plugs...just like a Y connector, but without the connector.
so basically, i run the fan wires where i have the wire going from + to - on the deans right?
so as soon as i plug in both lipos, the fan should turn on.
can anybody answer my question 2 post up above about keeping the fan in place.
thanks

I think i answered the other question over on the traxxas forum.

The fan should be wired to the first + and - points on either side of the Y, if its a ~6v item, or the first and last + & - if its a ~12v item.

I was going to strap my fan to the heatsinkclamp but mounted right to my chassis guard instead, this is what I would try doing if I were you, if not ziptie it she should be fine with no melting. Did you see my install I just used a little chunk of revo body post. It took me about 5 minutes to bolt in and wire up. Surely you have a spot to mount one like that.

on the emaxx 3905, there is no room at all to mount it. i would have to ziptie it or screw it right onto the rcm heatsink/clamp. which sucks cus its already high as it is, now with the big fan, its gonna be another inch higher. hopefully this wont mess with my cog.
maybe i can rig it somehow to mount it on the other side of where the second motor used to be...suicideneil suggested a l bracket.

Yea bro make something work cause the fan is super nice to have. Mine exceeded my expectations by alot plus you can gear up.

im hoping i get the same improvement as you did. if all is good, i may gear up a lil bit. so entire run on 8xl on 4s, your max temp was 155 and you ran your lipo down to lvc without taking a break? whats your mph?

Yes I ran for 23 minutes straight hammering the buggy and the temps dropped from 185 to 155 on a ten deg hotter day! My violator 9.5 has truck tires and was geared for about 38mph now I just stepped up from a 15 tooth to a 17 tooth and it really came alive...And now the temps are 160. Do it bro.

i am hahah i just ordered some last night. mine wont be mounted like yours though. im most likely gonna just ziptie or screw it right ontop of the rcm heatsink/clamp.
im wondering if blowing straight down onto the heatsink is not as efficent as the way you did it how its blowing at the motor and the heatsink. we will see... i hope these fans last for at least 2 months, hopefully 14.8v isnt too much for them.
just to be absolutely sure, please take a look at this link:
http://www.finedesignrc.com/batterie...esyharness.jpg
i solder the positive fan wire to positive on the left deans plug and negative fan wire to negative onto the right deans plug...correct?

Yep that's it. What size fan are you using? Mine are powerful 40mm units blowing right at the center of the heatsink with equal amounts of air blowing over and under the heatsink. Plus I have the large hole in the body where the engine was which allows lots of air to escape. I also have a vent cut in the front windshield which brings in even more air. The name of the game is AIR!

i chose the 40mm size fans like yours. i believe its the exact same brand as well...but just cheaper in price heh. for those of you interested here you go:
http://cgi.ebay.com/ws/eBayISAPI.dll...MEWA:IT&ih=020
$5.50 shipped for 3 fans.
i also have my front and rear winshield cut out for more airflow. i will first try just ziptieing it ontop of the rcm heatsink/clamp. if it works well that way, imma keep it. but if its not, then i may just have to build a L clamp of some sort so i can have it blowing at the motor and heatsink like yours.

Yea those are the same fans and your right very cheap. Its real nice having spares also. Everytime I run mine I'm tickled by how well it works...It's 60deg outside now and my motor temps are 125 and my mm is at 105!