WonTonsChicken

iTrader: (43)

That durango body looks good!! How did you go about narrowing your body posts?

werner sline

wow nice shape !

0verkill

iTrader: (8)

Those pictures are from Mav-07.

#3702
http://www.rctech.net/forum/electric...hread-247.html

0verkill

iTrader: (8)

I installed the Yeah Racing heat sink & twin fan setup today (YA-0261BK). It's pretty good quality. You cannot install as is right from the box because it's slightly larger than 40mm and it would just slide all over the motor. So I also ordered a 2mm sheet of thermal pad and just cut it to shape for the bottom heat sink piece. Not only does it help with heat transfer, now it doesn't move on the motor. The fans spin really fast (14,000 rpm) and they hook right up to the receiver.

The package includes optional 10mm spacers to raise the fans, does that really provide more airflow being higher?

0verkill

iTrader: (8)

Hot weather, taller grass, and 55+ mph speeds don't mix well with 30k center diff oil. It worked great in the winter though. I was doing my normal temperature check and the center diff case was 225F! And that was after I did several other things, so it was likely much hotter than that during operation. This extreme temperature caused the plastic case to soften/melt/distort and then caused the spider gears to shift in the housing and then grind. The gears are actually stuck and don't move at all.

The heat sink and fans for the motor work great and the motor was only 125F, which is awesome.

So what weight of center diff oil should I go with to lower the temperature?

100,000
200,000
500,000
1,000,000

Dr_T

Wow, nice one! Leave it like that and enjoy your newly made DIY center spool .

For what it's worth, my CD still went ~230F with 130k cSt, dropped to ~175F with Traxxas 500k WT (which some say is only ~300k cSt) and now with 2000k cSt it gets around 130F.

I would go as high as you can and just control (prevent) your wheelies with throttling smoother. You could also play around a bit with the Torque control feature on your Mamba. I think limiting peak Torque a bit electronically should have similar "feel" as blowing off excess Torque through the fronts with a light center diff, except with the electronic Torque limit the energy will stay nicely in your battery and won't go wasted cutting grass .

0verkill

iTrader: (8)

WOW, today was very expensive. Just melted a 2nd center diff! I picked up some Traxxas 500,000 oil and put it in my new one, that's the highest my LHS had. I checked the temperature and it was 268F!!! The motor was only 153. The gears started grinding again. I opened it up and the oil looked like black tar. Nothing is binding, the bearings are new.

1. Who carries 2,000,000 diff oil? Link? Anyone in the US? I see LMI Racing does but I can't read their website.
2. Who all makes aluminum differential cases?

werner sline

were those fans expensive ?

protect them, I damaged all the fans I didn't protect...

0verkill

iTrader: (8)

They came with the heat sink and they're only $5.90 from rcMart. I actually ordered some fan protectors the other day.

0verkill

iTrader: (8)

I see Team Associated has a new bottle of 1,000,000 cst diff oil, but they're showing out of stock on their website and they're not available anywhere else. I also see Mugen has a 1,000,000 wt bottle that's available from AMain.

If one of those doesn't work, I'll just have to change some settings on the ESC or gear down, at least when it's hot outside.

Justpassedu

iTrader: (118)

Really nice lil project you got going . I just read the thread and i am liking it. My favorite thing to do is throw in bigger than what i need or what the vehicle is meant for and see what it can do.

0verkill

iTrader: (8)

Thanks, everything I build is overpowered.

0verkill

iTrader: (8)

I'm going to try the Gravity RC 2.5 million cst diff fluid. We'll see if it can handle the heat. It looks like a quality industrial grade fluid.


Super High Viscosity Pure Silicone Fluids are high viscosity linear 100% Polydimethylsiloxane Fluids (CAS # 63148‐62‐9) that range in viscosity from 300,000cSt to 20,000,000cSt (centistokes). They are clear, colorless, odorless, and chemically inert to virtually all materials including plastics, metals and rubber. Hi‐Viscosity PSF Fluids possess excellent thermal stability, and exhibit little viscosity change at both high and low temperature.

Super High Viscosity Pure Silicone Fluids are extremely viscous fluids that possess both high damping properties and high resistance to shear without breakdown. They meet Federal Specification VV‐D‐1078 “Silicone as Damping Fluid”, and are used in a wide range of military, industrial and avionic gauges, meters, instruments, and monitoring systems.

Features and Benefits
- High Damping Action…meet Federal Spec VV‐D‐1078
- Excellent Lubrication
- Excellent O‐Ring Lubricant
- Inert to virtually all o‐rings, gaskets, seals and valves
- High Shearability without breakdown
- High Oxidation Resistance
- Compatible with a wide range of solvents
- Hydrophobic – water repellent
- Inert‐*improves stability and shelf‐life of formulations
- Low Vapor Pressure
- Excellent Thermal stability
- Low Viscosity change at both low and high temperatures

0verkill

iTrader: (8)

I picked up some fan covers from 3Racing (# 3RAC-FAN08). They sure beat making your own, they're only $1.40 each.

werner sline

clean stuff !