Anyone use 2s for crawling?

[svt923]

Originally Posted by Pant Danza

This. Seems like some of the stock esc’s lifespan shortens on 3s even if they are rated for it.

A lot of cheap ESCs have linear BECs (instead of the more efficient switching regulators of external BECs and better ESCs) which burn off excess voltage as heat, those tend to be what dies from running higher voltage. It produces a lot of heat to turn 12+V of 3S lipo energy into 5-6V for a receiver.

[Browneye]

If you do any trail walking with your rig where you're just driving it around while you walk a trail or a park or whatever, the speed 3S provides is the ticket.
Does not make much difference for competition style rock crawling. I do both, but all my 1.9's run 3S - they will crawl just as slow as a 2s powered one with the HW controller - it makes taming the 3S a breeze. Without it the rig is very jerky cuz of the motor speed. With the upgraded esc you dial in start punch, reverse percentage, drag braking, all that stuff which just makes driving it like butter. Great for competition!

I will say that my Bomber is happier for me on 2S - otherwise it is so stupid fast with brushless power that it will cartwheel. Talk about not scale. LOL

[mach2nh]

Originally Posted by hobbyjumper

Inspired when this thread came out and having 3s batteries in inventory, I upped with an open mind. The difference was higher top speed (impressive, but personally don't need) and the capacity to blast out of a jam like superman on RedBull (unrealistic...to me) when I might otherwise have backed up and found a less abusive line.

To each his own.

(Hobbywing 1080)

Feel the same way with my wraith. I love the run times with mt 5700 2s and have never killed it in a single outing.

[svt923]

Originally Posted by hobbyjumper

Inspired when this thread came out and having 3s batteries in inventory, I upped with an open mind. The difference was higher top speed (impressive, but personally don't need) and the capacity to blast out of a jam like superman on RedBull (unrealistic...to me) when I might otherwise have backed up and found a less abusive line.

To each his own, I guess. Not here to cause trouble, just reporting back. I intend to give it another go this summer, and see if the change of season changes my view. For now I have switched back to 2s.

The mantra is Volt up, Gear down; you only did half the job which is why your results were less than impressive.

Per the Holmes website:

Volt up, Gear down! This has been our motto for a decade, and it still holds true for motors of all types. Use 11.1v to 14.4v lipo whenever possible. Using voltage to gain motor speed while gearing down to slower wheelspeeds is win-win. Torque at the wheel is gained, low speed control is improved, and overall horsepower will increase as compared to low voltage and high geared systems.

[Browneye]

Plus a 3S system running around at half throttle lasts way longer than a 2S system run at a higher speed all the time. And it runs cooler.
In other words, run time is generally increased with 3S as well.

This has been born out on my bomber - it's too stupid fast on 3S so I run it on 2s instead of gearing down to get the wheelspeed I need/want. It works fine, but the battery life is half. [shrug]

I'm fine with that cuz I don't drive my bomber around for hours on end, but my 1.9 crawlers I do, so I want as long of battery life as possible. Volt up, gear down. It really works!

[TRX4ME]

I run a 2S shorty so I can locate it in front.

[svt923]

Originally Posted by hobbyjumper

I've been persuaded to investigate gearing down, probably in the Spring. It won't be ABC since bigger ring gears won't fit inside the housing. The stock scx10ii pinion is already a tidy 13T and there is a physical bottom limit to teeth count. Two teeth would be pretty interesting. The smallest Axial even sells is 11. I've geared down before, and a similar incremental change is virtually unnoticeable.

A 10T pinion should fit just fine, I don't remember if a 9T will fit with the stock spur though. Since the ratios jump pretty drastically with 32P gears, a 10T pinion would be a 30% increase in gear reduction and a 9T would be about 45%.

[Browneye]

Originally Posted by svt923

A 10T pinion should fit just fine, I don't remember if a 9T will fit with the stock spur though. Since the ratios jump pretty drastically with 32P gears, a 10T pinion would be a 30% increase in gear reduction and a 9T would be about 45%.

^^This.

@hobbyjumper - pinions are relatively cheap, so if you want to mess around with it it's a cheap date. I have been gearing my rigs down as they crawl better - slow speed control is improved. My Blazer got a 11T pinion and it works really well, definitely slower, but still enough wheelspeed for walking with it for trailrunning.



There are other options for the Ascender, but this seemed to be about the SCX10II.



Additionally, I have played with a slower and faster motor and related gearing up and down. A slower motor really does slow them down - one of my rigs got a 45T and it's pretty cool - is my best rock crawler. It has stock gearing too.

The one with a 27 got much lower gearing but is still faster than the 45T.



Changing gearing at the axle level is much more difficult. Changing spur or pinion gears is painless. The Axial is 32pitch, worth noting if you're shopping for gears. And hardened steel is recommended rather than aluminum - your set screws won't strip nearly as easily, and alloy pinions have been known to crack at that point with the smaller tooth versions. A drop of blue locktite is highly recommended. Put a lighter on it to remove if necessary - a little heat and they come right out. Same for axle hex screws - but I have quit lock-titing those.

[colbynobo]

When I get a new, RTR vehicle I will do the first run on 2S and then switch over to a 3S after about 15 minutes. That gets me into the ballpark for what I want. Then, I'll fine tune by adjusting the pinion. I run Hobbywing 1080s in everything so I already know the throttle is smooth. On my SCX10s I'm running 2S, my Gen8 is running 2S and my TRX4s are running 3S.

I very rarely go full throttle during my crawls. I like to do most of my driving at 1/3 to 1/2 throttle.

[Other]

I"m new to crawling and just built my first crawler SCX10II Cherokee. I ended up running a Castle Sidewinder 4 with a 27T brushed motor and 13T pinion. I've got a number of 5600-6600mah 2S batteries and find them to be just fine. Did a hike/crawl yesterday with my son (he's running an SCX10 II rtr) and after about a 2 hour run I checked the batteries and both were still over 7.7 volts so lots of juice remaining. I might consider a 3s at some point but don't see a need for it currently.

[HDMM]

Originally Posted by Other

I"m new to crawling and just built my first crawler SCX10II Cherokee. I ended up running a Castle Sidewinder 4 with a 27T brushed motor and 13T pinion. I've got a number of 5600-6600mah 2S batteries and find them to be just fine. Did a hike/crawl yesterday with my son (he's running an SCX10 II rtr) and after about a 2 hour run I checked the batteries and both were still over 7.7 volts so lots of juice remaining. I might consider a 3s at some point but don't see a need for it currently.

The thing with 3s packs are you can get, say like a 2200 mah pack which is half the weight of a 2s like the size you are running, which will lower the COG (center of gravity). I always was able to get atleast a couple hour run time with a brushed motor setup running a small 3s pack.

So less weight up top + Decent run time + More power = WIN

[Natedog]

Originally Posted by hobbyjumper

Who was it who said, "Try switching from 2s to 3s and you will never go back?"

Well, I've been running 3s consistently this spring. Huge mistake. 2s just seems so sluggish now.

3s throttle response is smoother, the powerband seems more usable, getting out of jams is more predictable (as long as you don't hammer the throttle).

Agreed, ran 2s for awhile, wanted more wheelspeed without 2speed tranny and 3s is the shiz!!!

Usually I don't need to gear down for it, just adjust my throttle finger and good to go!

[bestrccrawler]

Why not, I have used 2s and 3s for RC crawling. In term of the types of motor used. I have used a brushed motor as they are dirt cheap. Just don't use 80T as it is too slow. I think 50T is a good choice.

[Still Bill]

Ran 2S for my first month or so. But, now just 3S for better driveablity.

[Voodoobrew]

A stock scx10 runs at 4.65mph with a 13t pinion/56t spur, on 2s witha 35t motor.

You can change out the pinion and spur to 10t and 86t (or 87t) 48p gears. This will double your gear reduction.
Up the battery to 3s and you come in at 3.49mph slower, but much more torque and power.

Now up the motor to a 27t 540 and you get 4.19mph more power but slightly and to me not noticeably less torque then the 35t on 3s, but massive amounts more torque and power then the stock setup.

I have never had a set of 48p gears strip out on me, and all of my vehicles are 48p. I run 2 wraps of weight in my wheels also, the only thing I do to save the drive train is cut back on the punch in the ESC. My real crawler cant go from 0-60 in 2 seconds, I don't need my rc crawler to do it either. This also helps your batteries out by reducing the massive amp draw on them if you punch it.

This is the Idea behind volt up gear down.
Just volting up will give you more power and speed, but no more torque. you need torque to overcome obstacles and not bog down.
Just gearing down will increase the torque, this will allow you to creep over obsticles with out the motor slowing down as much.
when you dont have much torque and you crrep up the a log in the trail, the tires hit the log and stop because of the increased resistance, so you add more throttle until the tires climb over. once the tires get near the top and the resistance of the log is gone, a low torque vehicle will surge forward because you had to add so much more throttle to make it over. More torque makes climbing that log much smoother and a much more linear speed.

In my experience, changing gears and upping the voltage has a much more drastic effect than buying an expensive $80 brushed motor.
To me the benefit of a brushed motor is that they have a higher maximum rpm. Brushed motors are only good to about 30,000 rpm a brushless motor is good for over 50,000rpm

so on an scx10 you can run a 9t pinion and a 96t 48p spur with a total reduction of 104:1 install a 3,300kv brushless motor on 4s at 48 thousand rpms and a top speed of 6.28mph this combo will put out enough torque and power to rip your puny drivetrain to shreds if you so desired.

The point is faster motors and higher voltages don't need to make your crawler faster, by gearing down you directly convert speed to torque, and to me this is key for a happy crawling experience.
I have some $80 motors but the cost per value there is not nearly as good as spending the $15 on a lowe geared pinion and spur and a faster $20 motor.

[HahnsB2]

I still have a couple 2s packs. Great for kids, and still enough speed for them with a 3300-3500kv brushless.

[atholliday]

I use 3S 5200MAH and 2S 5000MAH in my Redcat Gen8 and i like them both. the 3S has a lot of wheel speed but it runs better on 2S more control and less burst. I am running a 12T Holmes Hobbie Trail master motor with a 12 tooth pinion.

[Natedog]

Originally Posted by mewalsh100

Once you run 3s or more, you'll wonder why you ever ran 2s.

X2, ran 2s for awhile, tried 3s and sold all my 2s. 3S is minimum battery I'd run now.

[Browneye]

Originally Posted by atholliday

I use 3S 5200MAH and 2S 5000MAH in my Redcat Gen8 and i like them both. the 3S has a lot of wheel speed but it runs better on 2S more control and less burst. I am running a 12T Holmes Hobbie Trail master motor with a 12 tooth pinion.

A re-gear and a HW1080 completely transforms this.

[Natedog]

I just swapped to 3S and really like it with HW WP1080 in most of my crawlers, didn't need to gear down, but everybody has different driving style. 3S is actually smoother startup, but with a little bit more punch ime, awesome when combined with Traxxas Titan 21T 550 motor!