First Kit Build - Need motor, esc, servo help!! Axial Capra

[PounceTheBear]

Hey guys!

I've only had RTRs. Recently got the Ryft - very fun! Unfortunately I wanted another one, so I got the Capra Kit. All of my electronics are Spektrum: radio, motor, esc, in other RTRs.

Looking around these forums, reddit, holmes hobbies, youtubes - harley designs, scale builders, etc. I'm lost. Folks say brushless, folks say brushed, folks say you need a BEC, folks say your ESC has a built in BEC but still need to use an external BEC, or that your steering servo can connect direct to the lipo with a JCT connection... None of that makes sense to me. Contacted holmes hobbies and that left me more confused than before.

I'm going to lock out the dig function. Where I will be driving around, and what I want to do, not going to need it, and I don't want it. That's not why I bought the Capra. So I don't need the micro servo.

I just want to have a good setup with some good torque. Mostly will be in the woods: lots of leaves, some larger roots, river beds & banks, while I build a few rock obstacles as I find them in the woods.

Servo: For the steering servo, I would rather stay under $100. I really don't want to have to purchase a BEC, because honestly, I know nothing about them. The more I read, the more confused it seems I become. Not really concerned about waterproof, because can't i use some plasti-dip and good marine grease to help seal it? If not, then I will need to filter for only waterproof ones and that's fine.

Motor: I heard holmes hobbies - trailmaster, crawlmaster and a few others. I would like to just use a Spektrum to keep everything I have spektrum based. Will the brushless Spektrum motor/ESC two-in-one fit in the Capra? https://www.horizonhobby.com/product/firma-2-in-1-brushless-crawler-motor-esc-1400kv/SPMXSEM1040A.html I have heard that for a brushless setup, I want to look for a "SENSORED" motor - I have no idea why that is, but what would be a good suggestion other than the Spektrum firma? Trail/Crawl/Puller Pro models from Holmes Hobbies? Don't I want to keep it at or under 2200kv? To me brushless seems a bit more straight forward/simple..?

ESC: I've seen the Hobbywing 1080 https://www.amainhobbies.com/hobbywing-quicrun-waterproof-1080-brushed-crawling-esc-23s-hwa30112750/p564169 for a brushed setup. If I go brushed that one is waiting in my cart. But what's a reasonable ESC for a brushless setup? Mamba X Micro seems too small, right? Mamba X waterproof is more on the costly side (one reason I like the Spektrum Firma so much - it seems like a decent setup at a price point I'm more comfortable with)

Sorry for the winded explanation. I'm trying to put all of this together while also learn a thing or two along the way. If I left anything useful our please ask away and I can provide more info.

 

[ferp420]

wow ill try to confuse you some more lol
your capra is vary high geared so you should go with a low speed high torque motor
the 2200 kv brushless motor is kinda the middle ground for torque and speed so anything higher will be more speed and less torque any lower will be more torque and less speed
brushed motors are usaly rated by turn count so a 27turn motor is usualy a good starting point but with brushed motors the higher the turn count the slower the motor so a 35 turn motor is slower than a 27 turn but has more torque a 20 turn will be faster but have less torque
brushed motors are much cheaper and more suited for specialized use like rock crawling
brushed motors are more exspesive but have a much wider range of uses they can go just as slow with goobs of torque and haul booty i have had a 2200 kv motor hit 60mph while still crawling at a snails pace
the sensor in the brushless motor allows the motor to turn extremely slow by allowing the motor to talk to the esc and not just dump votage in to the motor brushless motors with out sensors tend to stutter or cog when trying to go extremely slow but they go fast vary good and alot more efficent at speed than a brushed motor so there good for bashers or go fast rcs
the torque and speed can be fine tuned with a pinnion gear as long as your not to far off with the motor size and battery voltage plays a huge role also
servos are kinda a funny thing the realy good ones are realy good servos but the cheap servos are still pretty good
ds servos were the go to cheap servo for a long time on a crawler you want a high torque metal gear servo 25kg seems to be a good torque rating for smaller tire rigs im not real sure what 25kg works out to in inch pounds but if your buying a servi rated in inch pounds look for around 300 and up any less will likely not move the tires and like just about anything else more power the better
the capra if uzed at speed will need one hay of a beefy servo though so if your doing any more than just crawling spend the money get a servo with steel gears on the capra the tirez are the first thing to hit everything so that servo needs to be tough or your just gona strip gears every few runs
the problem with high power servos is they draw alot of power not realy a way around that there are 2 options for high power servos a external bec or a direct powered servo the cheap 25kg servo is right on the edge a quality esc will power it fine but some cheap escs wont the mamba line has kick ass becs up to 8 amps most are 3-5 amps

 

[PounceTheBear]

wow ill try to confuse you some more lol
your capra is vary high geared so you should go with a low speed high torque motor
the 2200 kv brushless motor is kinda the middle ground for torque and speed so anything higher will be more speed and less torque any lower will be more torque and less speed
brushed motors are usaly rated by turn count so a 27turn motor is usualy a good starting point but with brushed motors the higher the turn count the slower the motor so a 35 turn motor is slower than a 27 turn but has more torque a 20 turn will be faster but have less torque
brushed motors are much cheaper and more suited for specialized use like rock crawling
brushed motors are more exspesive but have a much wider range of uses they can go just as slow with goobs of torque and haul booty i have had a 2200 kv motor hit 60mph while still crawling at a snails pace
the sensor in the brushless motor allows the motor to turn extremely slow by allowing the motor to talk to the esc and not just dump votage in to the motor brushless motors with out sensors tend to stutter or cog when trying to go extremely slow but they go fast vary good and alot more efficent at speed than a brushed motor so there good for bashers or go fast rcs
the torque and speed can be fine tuned with a pinnion gear as long as your not to far off with the motor size and battery voltage plays a huge role also
servos are kinda a funny thing the realy good ones are realy good servos but the cheap servos are still pretty good
ds servos were the go to cheap servo for a long time on a crawler you want a high torque metal gear servo 25kg seems to be a good torque rating for smaller tire rigs im not real sure what 25kg works out to in inch pounds but if your buying a servi rated in inch pounds look for around 300 and up any less will likely not move the tires and like just about anything else more power the better
the capra if uzed at speed will need one hay of a beefy servo though so if your doing any more than just crawling spend the money get a servo with steel gears on the capra the tirez are the first thing to hit everything so that servo needs to be tough or your just gona strip gears every few runs
the problem with high power servos is they draw alot of power not realy a way around that there are 2 options for high power servos a external bec or a direct powered servo the cheap 25kg servo is right on the edge a quality esc will power it fine but some cheap escs wont the mamba line has kick ass becs up to 8 amps most are 3-5 amps

thanks! it helps to have someone explain it for what i'm looking for and not a generic response like i have been seeing.

Okay, so for a brushless i may want look for something under 2200kv. I think the spektrum firma is 1400kv.. but that doesn't seem like i will be able to use a BEC with that one? also not sure about it fitting in the capra body

with a brushed setup i would likely want to look for 20 turns or more. I don't really care about going fast. that's not why i got this one. The ryft is my fast off road.

in terms of the bec and servos. if the servo is direct power, will it be pretty straight forward how to connect that when i get it? or is that just dependent upon which exc/servo i get? makes sense why most folks are installing the mamba esc then. and i should likely look in that direction no matter if i choose brushed or brushless setups.

 

[soze]

My Capra ran a very long time using a DS Servo DS3235 35kg servo. It did fine. I've recently switched to an Armory RC Katana 500 servo.

I'm running a Hobbywng AXE 2300kv system in mine, but that's just because I wanted to. You can run fine with a brushed set using a Hobbywing 1080 and a brushed motor like the Holmes Hobbies Crawlmaster Sport series.

The All-in-one like the Hobbywing Fusion and the Spektrum version won't fit with the stock skid I believe.

 

[PounceTheBear]

My Capra ran a very long time using a DS Servo DS3235 35kg servo. It did fine. I've recently switched to an Armory RC Katana 500 servo.

I'm running a Hobbywng AXE 2300kv system in mine, but that's just because I wanted to. You can run fine with a brushed set using a Hobbywing 1080 and a brushed motor like the Holmes Hobbies Crawlmaster Sport series.

The All-in-one like the Hobbywing Fusion and the Spektrum version won't fit with the stock skid I believe.

for those servos, did you need a BEC setup? I'm starting to grasp the motor/esc. The BEC is throwing me for a loop. Isn't that one of the main reasons for an ESC, to divvy up power appropriately where it needs to go?

doh! I was really hoping that spektrum firma would fit, meh. thanks!

 

[twade984]

“Best” electronics setup is completely dependent on budget, and expectations.

If your priority is budget, but you want something reliable, a Hobbywing 1080, Holmes Crawlmaster sport, and ds3235 servo is imo, the best choice. Biggest downside with brushed motors, is that they will wear out and require replacement.

I’ve used that setup multiple times, it costs about $85, the bec is sufficient to power that servo, and the internal bec is capable of 7.5v, as is the servo, for max torque from the servo. Just make sure your receiver can handle it. It also has pretty darn good low end control for the cost.

If budget isn’t your first concern, brushless would be my recommendation.

The Hobbywing axe system has amazing low end control, is super quiet, but isn’t the most powerful setup. My understanding is the spektrum firma sensored system is essentially a rebadged Hobbywing axe. Again, internal bec should be sufficient to power servos up to maybe 400-500 oz in.

Some people don’t like the FOC function, I like it, but you have to be careful not to let it overpower and break things when you get a wheel bound up.

My current favorite setup is a castle mamba x and Holmes puller pro. Haven’t yet tried either of the two castle slate motors i just got. My understanding is they are comparable to the puller pro stubby power wise.

The mamba x is arguably overkill for crawling, but that makes them super reliable. They are tunable via castle link, have the auxiliary wire function, have a stout bec, and can be used for brushed or brushless motors. You can run a higher kv brushless motor (2200-2700kv) and still have tremendous low end control. Plus more than enough wheel speed for crawling and moderate hooning.

Servo wise, in my experience I’ve only used a couple servos priced near or under $100, and I don’t think they are worth the money over a ds3235. If I want a high end powerful servo, I like the protek 370tbl, Holmes shv800, and I think the shv650’s are going to be a great option.

Direct power servos are great, you only need to solder a jst connector to your esc’s battery plug. The shv650’s are now single wire, and use an adapter to run either off the receiver, or off a separate jst.

Either running less powerful servos, direct power esc’s, or higher end esc’s will eliminate the need for an external bec.

You could probably use a mamba micro x and slate motor, or puller pro stubby since the Capra isn’t the roomiest of rigs, but the micro x has a fairly weak internal bec.

My 10.2 swapped Capra is running a micro x/2700kv puller pro stubby, and shv800 direct power servo, and I’m very happy with that setup. Although gearing is much improved over the stock Capra axles and trans.

 

[PounceTheBear]

“best” electronics setup is completely dependent on budget, and expectations.

If your priority is budget, but you want something reliable, a hobbywing 1080, holmes crawlmaster sport, and ds3235 servo is imo, the best choice. Biggest downside with brushed motors, is that they will wear out and require replacement.

I’ve used that setup multiple times, it costs about $85, the bec is sufficient to power that servo, and the internal bec is capable of 7.5v, as is the servo, for max torque from the servo. Just make sure your receiver can handle it. It also has pretty darn good low end control for the cost.

If budget isn’t your first concern, brushless would be my recommendation.

The hobbywing axe system has amazing low end control, is super quiet, but isn’t the most powerful setup. My understanding is the spektrum firma sensored system is essentially a rebadged hobbywing axe. Again, internal bec should be sufficient to power servos up to maybe 400-500 oz in.

Some people don’t like the foc function, i like it, but you have to be careful not to let it overpower and break things when you get a wheel bound up.

My current favorite setup is a castle mamba x and holmes puller pro. Haven’t yet tried either of the two castle slate motors i just got. My understanding is they are comparable to the puller pro stubby power wise.

The mamba x is arguably overkill for crawling, but that makes them super reliable. They are tunable via castle link, have the auxiliary wire function, have a stout bec, and can be used for brushed or brushless motors. You can run a higher kv brushless motor (2200-2700kv) and still have tremendous low end control. Plus more than enough wheel speed for crawling and moderate hooning.

Servo wise, in my experience i’ve only used a couple servos priced near or under $100, and i don’t think they are worth the money over a ds3235. If i want a high end powerful servo, i like the protek 370tbl, holmes shv800, and i think the shv650’s are going to be a great option.

Direct power servos are great, you only need to solder a jst connector to your esc’s battery plug. The shv650’s are now single wire, and use an adapter to run either off the receiver, or off a separate jst.

Either running less powerful servos, direct power esc’s, or higher end esc’s will eliminate the need for an external bec.

You could probably use a mamba micro x and slate motor, or puller pro stubby since the capra isn’t the roomiest of rigs, but the micro x has a fairly weak internal bec.

My 10.2 swapped capra is running a micro x/2700kv puller pro stubby, and shv800 direct power servo, and i’m very happy with that setup. Although gearing is much improved over the stock capra axles and trans

I am starting to like the combo that you just mentioned: "hobbywing 1080, holmes crawlmaster sport, and ds3235 servo" I keep seeing the 1080 in lots of other posts, and another person even mentioned the same servo you just did in my thread. sounds like a good mix to have me on the trail without the need for a BEC.

What is "foc function"? motor/esc combo?

I think for right now, getting it up and going with brushless is ideal. once something starts wearing out, i will likely upgrade to brushsless.

Okay, so going to a higher ESC keeps me from having the external BEC. I like that, I don't want to fidget with more than I need to. And with that servo, if I ever go through two of them I think at that point I may need to adjust my driving style or just upgrade to a bigger/sstronger servo. thanks!!!

 

[twade984]

All things considered, I would definitely recommend that setup. It’s cheap, reliable, and fairly well proven. It’s also not overly complicated. That will get you up and running, and if you find something lacking, then you can consider investing more into electronics.

As a first crawler, I would save a few dollars on the electronics, and spend a little money on tires and foams.

With most Esc and motors, when you give a steady throttle input at low speeds, and the vehicle meets an obstacle, the motor will bog down, and you will have to give more throttle to maintain speed, or power over the obstacle. Over time you get a feel for it, and can tell just by throttle input weather your rig is bogged down, bound up, or working harder.

With FOC, it basically maintains speed for a given throttle input. So hypothetically speaking, If you get one tire bound up the Esc will automatically supply more power to the motor to try to maintain speed. It tries not to let the motor slow down. It can give a kind of disconnected feeling compared to traditional setups.

The benefit is ridiculous low end control, the fusion and axe systems are the slowest crawling setups I’ve ever used personally.

 

[PounceTheBear]

Good deal, thanks friend. Appreciate you!

Yeah, once everything gets in and I'm crawling and nto ripping through everything with the Ryft, I will start looking into brushless setups.

Capra is relatively light from what I've read so I am only doing 2 stage foams from ProLine. With brushless I might add more weight, but not with my brushed setup.

Thanks for input!

 

[ferp420]

. The BEC is throwing me for a loop. Isn't that one of the main reasons for an ESC, to divvy up power appropriately where it needs to go!

in the old days there used to be a battery pack to power your reciver and servos once tech started coming to the rc world they came up with a battery eliminator circite to do away with the 4 AA battery pack

the bec is just a low amp voltage regulator tacked on to the esc one of the issues with the bec is heat if you add to much of a amp draw it gets hot and can burn out sometimes the esc still works some times it dosent usualy it dose but not always

1 ds25kg servo is close the max for most becs but as long as you dont have to many other accesorys like lights winches or shifting/dig servos you should be ok
there are tricks to keeping the servo from pulling to many amps from your bec one is setting your endpoints on the radio so the servo dosent try to push past the steering stops another is a glitch buster it gives a few seconds of extra power but more of a bandaid for a poor set up or over agresive driving style

 

[nightcrawler48]

Seems the BEC is your stumbling block. All the standard ESCs have a built-in BEC but there is no standard for the BEC output voltage and amp rating. Typically the BEC voltage from the ESC would be fixed at 5 or 6 volts. Now there are some ESCs that are over 6V, 7.4V for sure, but I'm not of aware of anything higher than that. You have to be careful though as most receivers are rated for 6V so a 7.4V output BEC could cause some issues.

ESCs with built-in BECs can be rated as low as 1 amp max. That 1 amp has to power the receiver (generally not much amp draw) and the steering servo if the servo is getting its power from the receiver. The issue is, most servos will draw more than 1 amp and some power hungry servos can draw 5 amps or more. The built-in BEC just can't handle the amp draw.

So this is where the external BEC comes in. Some relatively inexpensive external BECs are fixed voltage, usually 6V, and rated around 3 amps and possibly with a momentary peak of 5 amps. A more expensive Castle Creations (CC BEC) is rated 25V (6S) input voltage, adjustable 4.8V to 9.0V output and 10 amps. The output voltage can be adjusted using the Castle LInk and the CC downloaded software on your computer.

The bottom line is, if you get in to the higher torque rated servos, you would definitely benefit from an external BEC. And, the higher torque servos generally get their torque rating using voltages higher than 6V.

Best thing to do is, look at the specs for the electronic components you are planning on using and make sure they are voltage compatible.

 

[soze]

for those servos, did you need a BEC setup? I'm starting to grasp the motor/esc. The BEC is throwing me for a loop. Isn't that one of the main reasons for an ESC, to divvy up power appropriately where it needs to go?

doh! I was really hoping that spektrum firma would fit, meh. thanks!

I didn't need a BEC for either of the servos I mentioned, but I am running a Hobbywing AXE. With that being said... I've had a few setups with the Hobbywing 1080 + DS3235 which is just fine. For the Armory RC servo it runs fine on a Hobbywing AXE without BEC and gives 500oz at 7.4v, but you can run it at 6v but get less torque/speed. If you used a BEC you could get 556oz at 8.4v. I'm running it just at 7.4v for simplicity. I have FS-BS6 Flysky receivers that can also handle the 7.4v. I've also got the same servos paired with Hobbywing Fusions and Hobbywing 1080s all running at 7.4v.

 

[King Dork]

doh! I was really hoping that spektrum firma would fit, meh. thanks!

I’m not 100% certain that the Spektrum 2 in 1 system will not fit. People do fit 550 sized motors in stock Capra setups after doing some trimming to the rear link mounts which still work as long as the links are in the lowest mounting hole is what I understand. Now the Spektrum 2 in 1 is shorter than the Hobbywing Fusion (comparable to a 550 can motor) by 6mm per the description, putting it between a 540 and 550 can size. So even if it required some trimming of the rear link mounts it should not be as much. Knowing this I’d personally buy the Spektrum system if I wanted one and grind a little to fit it if needed. Of course it would be nice if someone is currently running this combination and can confirm if it’ll drop straight in.
Also keep the Castle Copperhead esc on the radar. After the Mamba X the Copperhead still has a impressive internal bec that should handle most non direct power servos. I have a Copperhead in one of my TRX4s powering a Powerhobby 729MBL servo at 7.4v for 500oz/.10sec and it has no issues. Copperhead will also run brushed or brushless motors and has butt loads of adjustability. Just a couple things to think about.

 

[PounceTheBear]

I didn't need a BEC for either of the servos I mentioned, but I am running a Hobbywing AXE. With that being said... I've had a few setups with the Hobbywing 1080 + DS3235 which is just fine. For the Armory RC servo it runs fine on a Hobbywing AXE without BEC and gives 500oz at 7.4v, but you can run it at 6v but get less torque/speed. If you used a BEC you could get 556oz at 8.4v. I'm running it just at 7.4v for simplicity. I have FS-BS6 Flysky receivers that can also handle the 7.4v. I've also got the same servos paired with Hobbywing Fusions and Hobbywing 1080s all running at 7.4v.

Thanks! I went with the brushed setup you mentioned - 1080 and the DS servo. I'm not doing anything crazy with my setup, so I think i should be fine with the brushed system for a while.

I’m not 100% certain that the Spektrum 2 in 1 system will not fit. People do fit 550 sized motors in stock Capra setups after doing some trimming to the rear link mounts which still work as long as the links are in the lowest mounting hole is what I understand. Now the Spektrum 2 in 1 is shorter than the Hobbywing Fusion (comparable to a 550 can motor) by 6mm per the description, putting it between a 540 and 550 can size. So even if it required some trimming of the rear link mounts it should not be as much. Knowing this I’d personally buy the Spektrum system if I wanted one and grind a little to fit it if needed. Of course it would be nice if someone is currently running this combination and can confirm if it’ll drop straight in.
Also keep the Castle Copperhead esc on the radar. After the Mamba X the Copperhead still has a impressive internal bec that should handle most non direct power servos. I have a Copperhead in one of my TRX4s powering a Powerhobby 729MBL servo at 7.4v for 500oz/.10sec and it has no issues. Copperhead will also run brushed or brushless motors and has butt loads of adjustability. Just a couple things to think about.

Oh nice. I'll look into it a bit more then. If it doesn't fit I can toss it in my Ryft and have a slow Ryft for a while lol.

If you do end up getting the Spektrum, please shoot me a message to see if it fits and if you had to do any modifications. I'll look into the Copperhead. I would like to do a brushless system one day, but the brushed gets me going relatively affordable. Thanks again for the advice/input!!