Need to replace Mamba motor in FLM Rusty

[dadgummit]

I have a full FLM Rustler that weighs 6 pounds including battery. Right now it has a MM 5700 system and I was thinking on replacing the motor with something more efficent. I was looking at the Lehner basic XL series (either 3600 or 4200KV since I have a ton of 6 -7 cell nimh packs). Will the Basic XL pull too many amps for a nimh pack?

The rusty's spur gear is a 48 pitch so I think I am really limited to the basic XL (with a 1/8" shaft) for the motor I can use. Does anyone sell 48 pitch pinions with a 4mm or 5mm bore?

[mach1stang]

do what i did i have a flm pede with all ext stuff i have a feigao 6L (4096 kv i think) in it with a 7 cell pack and see if you cant find a 5mm pinion to fit a jato spur (i am trying to see if mike could make me one) and you should be good. mine with a 12 tooth pinion and a 56 tooth spur is caculated to about 40-45 mph.

What a 1908 neu? Or will this cog? Eventho its a smaller motor. I would get a lehner 1920 or something.

lehner or neu for sure

[mach1stang]

i thought the neu motors cogged when mated to the mm?

[BrianG]

They do unless you gear low enough...

[dadgummit]

I like the idea of using the Jato spur gear. I just looked on tower hobbies and it says "54T 0.8 Pitch Spur Gear"
Is 0.8 pitch the same as mod 1?
Will it fit under the rustler's gear cover?

I thought the 15 series neu motors all came with 5mm shafts. I was trying to get away from having a custom pinion gear made.

Thanks for the quick replies!!!

[BrianG]

No, Mod 0.8 pitch is VERY VERY close to 32p. The jato uses Mod 0.8 spurs, but I use 32p pinions and it has worked perfectly for numberous runs.

True conversion: 32p is Mod 0.79375

[dadgummit]

That is great since Mike has 5mm bore 32p pinions in stock. Now I just need to choose a motor. I think that a 1509 1y would be good choice or maybe the next step up in KV. That would also save me from having to go to fine design!!

I also picked up a Quark 125b on Ebay pretty cheap.
http://cgi.ebay.com/ws/eBayISAPI.dll...m=170144101113
I can use it in the rustler, I am a little hesitent to use it in the 8ight-t I am building after reading all of the heat issues everyone is having. I guess I can do the heat mod though.

[BrianG]

If you go with a Neu motor, you can run upwards of 40k rpm without issues because of the higher quality.

That was a good price for the Quark. It's gonna look a little large in a Rusty, but won't hurt anything. Before you install it, you might want to consider the internal mod to help with temps, but it should be fine for now (until the internal thermal tape gets old and lets go).

[dadgummit]

In the pictures it is one of the white wire esc's which I think means it is one of the earlier models if the quark. Where can I get the piece of aluminum for the heat mod? Can Mike mill one up for me? Also should I replace the piece that is in the middle? Please keep in mind that Dean's plugs are about the extent of my self taught soldering ability. Can the mod be done without removing the motor wires?

[lincpimp]

Originally Posted by dadgummit

I like the idea of using the Jato spur gear. I just looked on tower hobbies and it says "54T 0.8 Pitch Spur Gear"
Is 0.8 pitch the same as mod 1?
Will it fit under the rustler's gear cover?

I thought the 15 series neu motors all came with 5mm shafts. I was trying to get away from having a custom pinion gear made.

Thanks for the quick replies!!!

The jato spurs will not fit under the stock gear cover, but it does not matter as 32p gears are not affected with dirt and grit like the 48p ones are. I run my pede with jato spurs and emaxx piions and have never had a problem stripping gears. It is also quiter than 48 pitch and smoother too. I wonder why traxxas still uses the 48 pitch?

Another possibility a Mega Motor ACN 22/30/?. You can get those with 1/8 inch shaft. They are 6 pole motors and work great with the MM. I think Mike can get these motors too.

Then you can stay with 48 pitch or go 32 pitch.

[suicideneil]

Originally Posted by dadgummit

In the pictures it is one of the white wire esc's which I think means it is one of the earlier models if the quark. Where can I get the piece of aluminum for the heat mod? Can Mike mill one up for me? Also should I replace the piece that is in the middle? Please keep in mind that Dean's plugs are about the extent of my self taught soldering ability. Can the mod be done without removing the motor wires?

No need to remove any wires, so you're safe there. I believe the aluminum you need is either 1/8" or 1/4" thick (can never remember, BrianG where are you?), and is stuck down onto the fets with Arctic Alumna thermal epoxy, and then thermal grease is applied to the top of it so that it makes good contact with the inside of the esc case. The middle heat spreader is more fiddly so is best left alone.

[BrianG]

Originally Posted by suicideneil

No need to remove any wires, so you're safe there. I believe the aluminum you need is either 1/8" or 1/4" thick (can never remember, BrianG where are you?), and is stuck down onto the fets with Arctic Alumna thermal epoxy, and then thermal grease is applied to the top of it so that it makes good contact with the inside of the esc case. The middle heat spreader is more fiddly so is best left alone.

Lol, I'm here. Yeah, it's 1/8" thick. The stock is less than that, but you lose thickness when you remove the pads. Here is a pic:



And yes, use thermal epoxy on to secure the heat spreader to the FETs and to the case. Otherwise, movement of the PCB when running will reduce the effectiveness of regular thermal compound. And make sure to use Arctic Alumina thermal epoxy because the regular AS epoxy has silver particles in it.

[dadgummit]

Very cool!! That pictrue is probably better than 100 words!! I just e-mailed Mike but maybe you can answer this: Can I order the 27x37x1/8 piece of aluminum from Mike? Thank you for all of your help!!