Crawler Canyon Presents: Servo Testin' Time, Flash Hobby 45kg, 50kg, & 60kg
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- เผยแพร่เมื่อ 2 ธ.ค. 2022
- We religiously over-test three offerings from Flash Hobby (one of my favorite Amazon brands) which include 2 direct-power, and one RX powered (though even that one is rated for 8.4V.
Some of the numbers are... surprising.
IG: crawlercanyon - ภาพยนตร์และแอนิเมชัน
Thank you for putting this together! There was a lot of very useful information in the test you provided
I definitely appreciate the time and the testing of these servos. You have really helped me in determining which servo works best for the money. Thx, definitely informative review 👍 👍
That just made me REAL happy that I got the 60kg on sale for $50.39 on Black Friday!! Great tests and RIP servo horns!
I love watching these tests thank you!! Like see the NSDRC budget one cant wait see what numbers it puts out!!
Well, I found this video a year after you posted and decided to purchase the 60kg and left the 40kg in the cart for a trail truck being built in the future thanks for shedding some light on these budget servos I know it takes a lot of time to make a video like this and it’s not for everyone. Keep up the good work you gotta sub form me
These tests are great, can’t wait to see you test AGFRC. I’ve been planning my 86BHMW for my next build, really loved it in my Gatekeeper at 7.4 but I added some lights that don’t like that so I went to 6v and direct power. But now I’m wondering if the 60kg Flash Hobby might be a better bet for the Vanquish kit. .
I always swore buy the expensive big name servos then tried the EcoPower WP120 and liked those for $70 then I decided to try that 45kg and put it in my Power Wagon with 1.9 Swampers and it didn’t fail once. I now have 3 of them. Looks like I’ll be buying one of those 60’s for a Ryft build. Thanks for the video.
Well done. I hope to come see you right after the1st of the year. I have a Warn winch on one of my cars. the specs on it say it can deadlift 100lps and pull 75lps. I think it be fun to test.
Loving this series. Now I know the 60 is the way to go for my heavy, tall tired rigs
This series is great. Maybe you could rig up a test for servo speed as well? Seems like the trade-off for more torque is less speed and vice-versa. For the cheap servos I use, I always assumed the different torque ratings depended mostly on different gear ratios, but I never looked into it.
Great series. I was thinking about buying the 50kg, looks like I'll be getting the 60 instead.
Looks like you’ve found another high value high, performance option. 👍🏼
I swore by the 50kg, heading to the 60. Thank you for this👍
Same. The 50s I own are the only 50s I'll own. The 60 is absolutely worth the extra couple of bucks.
Great video. Have you found any replacement gears for these? Also would you go with one of these or a 3 brothers rc g13 pro. Im looking at both trying to decide on 1
It's nice when low budget parts do what they say on the tin. Good job, Flash Hobby!
While others have done a similar style of video, I have to say I like your format and commentary the most. Excellent job on these videos. Its surprising that you get different results with a lower voltage on that servo. My guess is that its tuned internally for 7.2v? It can handle 8.4v but that doesn't mean its best operating cycle is at that voltage rating. I'll set here and shrug as I ponder that.
Great work on these. Can't wait to see what else you get with your inventory, or even what kind of variance you see between different examples of the same part number. I would add that the stronger arm for the 60kg servo will read a tad higher relative to the stripped horns if the hole center is closer to the rotation. The closer the rotation gets to the axis, the more power you'll read. Think of it like lifting a bucket at arms length vs hanging at your elbow. Your shoulder has to work less hard when the weight is closer. I have to wonder if AGF is making those servos with part numbers like BHW, but maybe others have adopted that convention
You got me to walk outside again, and it's exhausting! The blown up horns are 24mm from hole-to-hole, and the hole I'm using on the "big horn" is close enough as to be 23.5mm. That could still account for up to 2% (if everything scaled linearly) but it shouldn't be an issue moving forward, as that horn is now THE horn.
@@CrawlerCanyon I know you're doing your best to do these right. People will nit pick these types of tests to death and overkill. Really just trying to offer constructive feedback to help work out the bugs now rather than in a few months when the algorithm catches these tests and the rest of the peanut gallery joins in :)
It's also been years since I took any physics, so I couldn't tell you if that difference is linear or exponential, or other. Maybe that's another test! Difference in torque moving in each hole. I went shorter on my 4WS truck to give the servo a little help, but nobody can say how much you get
Love these kinds of videos. Good job. Would you please consider testing the Amazon 20kg along with the blue case 35kg and compare the results to the 25kg that you already did?
I I have a 20kg in service as a dig servo on Zoidberg, but I'll have to flip him over to check-- it may well be another 25kg.
I wouldn't mind replacing that one with something a bit quicker, as for the dig I'm willing to give up some torque for speed.
So if it's a 20, I may well pull it out of the rig to test. And it is NOT FUN to remove.
@@CrawlerCanyon I buy the 20kg in packs of 4 because they’re cheap and pretty reliable. I know they’re not terribly strong but they’re better than a lot of RTR servos and I’d be most curious to see what the ounce/$ would come out to.
wonder if a TRX4 horn holds up to the bigger servos. sure they can cost 7x more than the cheap amazon specials, but for me they have been incredibly stron and reliable
Is there a really strong servo? Could also be 5th scale (120 kg/cm) would be cool to get some ideas. Could also use 720° and a gear but need to lift realy strong. Speed is not a big problem
JX b130?
have you tried the 9imod 70kg yet ?
I keep coming back to this video cause I need your opinion once again. I’m going to build a Rock Pirates Interceptor chassis with dual steer on Capra axles with 2.2 tires and I wanted to ask if it would be smart to power the 60kg servos through a Y harness to the same 3s lipo that’s powering the truck or would it be better to try and add a second battery to the truck? Thanks.
The peak amps on the Flash Hobby servos is pretty low, and rear steer isn’t really taxing- so I’d say a Y-harness is fine. I’m running two 60kg on my Ryft that way.
Wow, all these servos are super baller. I'm not sure you were calculating the torque right though, from what I can tell these all way way overperformed. 50kg/cm means it should pull with 50KG of force at 1cm out. you had these at 2.4CM out so it should pull less than half that, the further out on the arm you pull from, the more distance you can pull, but the less force you pull with. Even that 45 pulled extremely hard.
When I wear out my cheapo 20kg red servo I'll be picking one of these up.
I measure torque at oz-in. Well, I do the raw pull, then adjust to 92.5% because the hole on my servo arm is 24mm from center an not 25.4. I then take that number and divide it by 13.88, which gives kg-cm. More accurately, ozf to kgf, which is ounce force inches to kilogram force centimeters. 50kg-cm (50kgf) is ~694oz-in (694ozf.)
All of these servos beat their manufacturer spec, but only by a few percent (at most.) The M60BHW averaged 838ozf, and is mfr. spec'd at 833, so that's 100.6% of spec.
Sorry if I missed it but that 45kg servo, is it the coreless or brushless version?
It's the CHW, so I'm gonna guess coreless. That would explain the speed. Now I'm curious as to whether or not the BHW would be as amp-hungry.
Will you do the 9imod 45kg coreless and brushless please
I would be absolutely flabbergasted to find out that the 9imod DSC45MG and HV45MG are NOT a different seller's versions of the Flash Hobby M45CHW and M45BHW (respectively.) BETU doesn't even bother to rename it, they have a identical-save-for-the top of case DSC45MG. Same for the YANTRS D5545GS. There aren't that many different servos on Amazon-- there are just a lot of names for a handful of servos.
End of the day, all of the aforementioned servos are within a few bucks of a Flash Hobby M50BHW, and I'll take direct-power every time.
Have you seen the 9IMOD Brushless servos for 40 bucks on Amazon? Very curious what these test out at. The speed is really good.
I have not, but I will be taking a look.
@@CrawlerCanyon I'm strongly considering buying in bulk and swapping out all my RTR servos with it
What is the horn you had to use on the 60 and where could someone find it
I have 2 of the 45’s. Neither cost me $40, I think the most expensive one was $38.
I have a question.The 50s and 60s are reversed is that going to affect my steering?when I turn my transmitter to the left, will it turn right and when I turn right will it go left ?
I haven't met a radio yet that doesn't have reversing for Ch.1, so it should be no issue at all. Though if you have a bunch of trim dialed in, it will flip the trim the other way (so if the wheels are "normally" pointed left, they'll now be pointing right.)
But without reversing the channel, yes, it will be reversed.
Out of these which would you recommend for a TF2 Marlin Crawler?
The 60kg is the value of the trio (ounces of torque per dollar) and even though it's overkill for a Marlin (I run a 32kg AGFRC in mine) so long as you make sure your endpoints are set, the 60kg is one of my top servos overall. Better to have the torque and not need it, right?
Does it make a difference on where on the servo horn the link is attached,,, ie more torque the shorter the horn and less torque the longer the horn is, is that where torque per cm comes from
From what I understand, torque measurements are done at 1" from the output shaft. The longer the shaft, the more mechanical advantage, so more torque-- as Archimedes said, "give me a lever long enough and a fulcrum on which to place it, and I shall move the world."
My numbers, if anything, should be a teensy bit low-- the horn I'm using now is like 23.5mm center-to-center. But it's strong enough to handle it.
@@CrawlerCanyon You've got that backwards. A shorter servo horn gives more leverage to the servo.
I bought the 60kg one but my right is left and left is right. Anyone else having this issue?
That’s why I haven’t purchased it was wondering if that would be a problem
Can it not be reversed in programming
@russcole5685 I figured it out. Don't remember what I did though. Lol
So do you buy the 270* or the 180* servos for 1/10 scale crawlers? The 270 degree are a lot cheaper!
Whatever's cheapest! I haven't noticed a difference in performance between any of them. From what I understand, the radio protocol determines the throw-- and 100% EPA for surface is 90º. Air stuff needs bigger throws for landing gear and whatnot. At least so far as I know.
@@CrawlerCanyon thank you for the quick reply sir!
This may be a silly question, but do you purchase the 180° models for your crawlers? It looks like the 60kg is available in 180°, 270°, and 360°.
So weird, I thought I had responded to this. I think every Flash Hobby I have is 180º, save one. The 60kg I just put into Jake is a 270º (at least it says so on the case) and so far as I can tell, it behaves exactly the same. From my limited understanding, a transmitter has to have something about it that allows it to use that extra 90º, and I don't think any of our radios do. I think I have a 270º or two in the cheap Amazon blue/red cases, and they behave exactly like every other servo as well.
@Crawler Canyon thanks for the reply! This 60kg Flash Hobby I bought is my first direct power brushless servo, I'm excited to try it out after Christmas. The last few servos I bought are 180° so that seemed like the right choice, but it doesn't hurt to ask because I have no experience with these direct power monsters.
I bought the 60kg but left is right and right is left. I can't find the programmer for this. Are you directions reversed?
@@MrCovain the 50kg and 60kg are “reversed,” but we just set channel 1 to reverse on the radio. I don’t know if there’s a radio that doesn’t have channel reversing. It’s pretty standard.
@Crawler Canyon yeah. Right now I'm running stock traxxas radio. I had no plans of swapping radios.
Torque is kg*cm, not kg/cm. For a constant torque a longer arm will give less force than a shorter arm.
So long as all of the servos are tested on horns of the same length, it's all a moot point. I'm not giving or taking mechanical advantage to/from any of the servos.
How can I run the 45kv hv at 7.4 volts with a 3s 80c battery
Should the linkage be at 1 cm from center rotation? It looks like it is about 2.5 cm
Torque is measured 1" from the center of the servo splines. The double-clamping horn I use is actually 23.5mm, so I then correct torque by multiplying by 0.925.
The closer the linkage is attached to the horn, the more relative torque is produced. At ~13mm from center, measured torque is increased by roughly 50%.
@@CrawlerCanyon Ok, I see what you did with the conversion. Is there anyway you could run the test with 10mm from the center, at 8.4V? I do not know if the plastic control horn would be strong enough for that test. Thanks
@@switchcrafters2516 the lowest hole on the testing horn is 13mm from output center. I’ve only tested one servo on the lowest hole, the AGFRC A86, which makes ~900oz @ 1”. At the 13mm hole it read close to 1,500oz before the rod ends on the linkage ripped apart. So the answer is… a lot.
The formula to get kg-cm from oz-in is to just divide the ounce number by 13.88.
@@CrawlerCanyon Hey, thanks a lot for the info. I have parts coming with a different 25T servo horn that I can get the 3/8" from center position. I have to be able to pull 80-90 lbs to pull the clutch cable. Once I get to 180 degrees, then it should not require the high current to hold it there.
Thanks again, Bruce
why dont you tighten the two spline clamp screws!
They were tightened. Blew right through them. Those lil' 2mm fellas help, but they're not magic.
That's why the current testing horn uses two 2.5mm screws, clamping from the same side.
Here to report that the 14v 50 kg lasted about two hour-long trailing sessions and about an hour of technical crawling running on 3s before it developed Parkinson’s. It’s still working, for now, but it will spaz out and I think it wants to die.
Forgive me if it sounds like I’m trivializing a terrible quality of life impacting disease.
I’d love to see some more Amazon servo reviews and long term durability reporting! There’s gotta be something out there sub $70 that holds up…. Right?!
I guess I:m lucky so far, as I've just got the one jittery boy-- maybe we have servos from the same batch? I have (I think) four 50kg and maybe six 60kg, and all of them are fine. Someone smarter than I could (I think) hook it up to a servo programmer and widen the deadband to stop the seeking. My noisy one still works just fine other than the twitching. I mean, end of the day, I know the solution: spend more money and buy AGFRC.
How do i know how many volts ill be running my servo at? My esc is the blx 185
That ESC has a 6V, 3A internal BEC. Which is... not a lot.
@@CrawlerCanyon so I should upgrade my esc if I want to be using a 600 oz servo? What if I do direct battery servo?
@@thomaswalton9089 You can go direct-power for the servo (but if you're running 6S there aren't a lot of options) or you can add a larger external BEC to run your servo.
@@CrawlerCanyon ok thanks this is all new to me I'll look into it
What a bummer, I just bought the 50kg one
Well, it's not as if the 50kg is a dog. Consistently made around 46kg, which is plenty good.
@@CrawlerCanyon true
Thx for the video. It seems as if the distance between the center point of the turning axis of the servo and the centerpoint of the rodend, which is attached to the servo horn is more than 10mm/ 1cm. If so, the measuring is incorrect. If its longer, the kg/ oz reading will decrease. The kg rating is given at 1cm lever arm. It has to be exactly 1cm, or your meaauring is inaccurate.😅
Torque is measured in oz-in. If you divide that result by 13.88, you get kg-cm. Math is amazing, isn't it? Also, torque is linear, so the point of measurement isn't significant, as little bit of that good ol' math will tell you the torque at whatever distance you want.
@@CrawlerCanyonif you would have used math the right way, then it would have been amazing, but you didnt. What do you think kg x cm is? Frorce times leverege length, N x m, or Nm. And the given unit in this case is kg x cm. But you just took the given reading from the scale and converted oz into kg x cm and not oz-in in kg x cm, but also just just wrote oz=kg in your stats, which is an absolut beginner error in math. If you would know math, you would have known, that units are the most important part of it.
You never stated that your leverege length is exactly one inch, or wrote it in your stats. And 438oz = 12,4kg and not 31,5kg. Amazing isnt it?
So either you did a conversion error, or an unit error and does not entitle you to be arrogant, giving me an atitude and speak down towards me. You did an error and not me. So be angry to yourself.
Building a testing rig in a scientific way to be able to measure the torque of an toy servo, to know exactly how much difference it does, compared to what the manufscturer states, but making such an error contradicts the hole approach of it, and makes your "accurate" measuring completely senseless.
@@G.J.G.P. the best part of this is your confidence. It's the confidence of someone who thinks they're absolutely, irrefutably right. But the fun part? You're not. You have no idea what you're talking about, you're just so, SO confident. And that, ladies and gentlemen, is how ignorance works. It's kg x cm, it's kgf-cm, because a kilogram is a unit of mass, and torque is a measurement of force-- hence the kgf. What we (who know what we're doing) is measuring the to move a mass a given distance-- oz-in, then corrected for the length of the servo arm (24mm) by a correction factor of 0.925 to show a proper oz-in, then converted to kgf-cm for the folks who don't use imperial. A servo putting out 500oz-in at 24mm corrects to 462,5oz-in @ 1", and 33.3kgf-cm for anyone interested.
You did at least get one part right: 438oz-in is indeed 31.56kgf-cm.
@@CrawlerCanyon you are the funny one here🤣. 1 Nm of torque = 10,2kgcm. And no, it isnt minus (-), its multiplied(×). And yes, kg is a mass unit, but you can easily convert kg in to N by multiplieng it with 1g ( 9,81m/sec²). But im aware of it, that you didnt know what N or kg is, or that they are relatable units, bscause youre used to imperial units.
But of corse im the one of us two who is clueless. Your not even using the right unints, so dont act as if you are the one who has the knowlege.
And the calculation in the and could be right, i did not check it, but us still did the error, by not mentioning the right units. And that is constant.
@@CrawlerCanyon i just saw your explaination about N, kg and kgf( ?) . Dude it doesnt matter if you put f behind kg. Its still 1kg. And 1kg × 9,81m/sec² = 10N. And 1cm is the 1/100 os a meter (m). So you dont need to tell me how the metric system works, which im using since day one.
The 45 kg servo is kind of pointless because it pulls so much current you would need a BEC to properly feed it. You can buy a 60 kg direct power servo for less than the 45 kg and a high current BEC.
Those amp draw numbers from the 45kg still give me pause. That servo is HONGRY.
Luckily, I have BECs for both of the 45s here. But much like the case with the 50s, the two I have are the only two I'll have.
That 60kg is the bargain of the group for sure.
Why are you quoting 4S voltage at 3.7v/cell and 3S voltage at 4.2v per cell. A fully charged 4S is going to be 16.8v. Also not seeing anything about 15v max rating for 14v labeled servos on Amazon.
Found the 15v reference . . .
Yeah, the Flash Hobby servos are not explicitly "4S direct." I'm running both of them on 4S all day on a 4WS rig, and intend to continue doing so, but know that if one (or both) blow up on me, I'm running them at a higher voltage than they're rated for.
While we're at it, having a servo with a max input of 14/15V is just... weird.
looks like a AGF servo
Very different sound on the AGFRC compared to the Flash Hobby servos. Not saying that AGFRC isn't the OE, as they may well be, but I don't think AGFRC is selling their own versions of what Flash Hobby is offering. The 9imod 60kg is cosmetically (nearly) identical to the Flash Hobby M60BHW (I think it's actually the same case) but very different inside. The 9imod uses helical-cut gears (which Flash Hobby is now using in their 60kg HV 8.4v model) making it one of the loudest "drivetrain noise" servos I've ever heard. It really does sound like some kind of grinder.
You have to clamp those horns to the servo everytime you put it on that’s why you stripped them.
While i have forgotten to clamp the $2 horns a couple of times (or more) in the past, the 60kg does not care if it's clamped or not. It tore the splines out of a brand new out of the package, double-clamped horn. 800+ ounces all at once is more than the $2 horns can withstand.
Not bad for the price...
When I checked this morning, the 45kg could be had for $41 with a $5 off coupon, so 36 bucks. I think thats a great servo for ESC power at that price, though it is a bit amp hungry. Of all the servos I've tested so far, it's the "real world fastest." Something like 0.20 seconds for a full 180º, while some others take that long to throw 60º.
@@CrawlerCanyon I really want to see to AGFRC servos match up against theaftermarket ones they make for others ...I have a JX 46 kg in my Element Enduro with a HW Fusion 2 in 1 ..parden me for sayin it sucks not sure if power issue with esc or servo... JX 46kg if it can do 25 kg lucky...
@@tomandrews5392 I remember seeing that the JX servos are pretty well overspec'd-- but I take that with a grain of salt until I get a chance to test it myself.
But if the JX 46kg is anything like the Flash Hobby 45kg, it's probably way too power-hungry for the Fusion's internal BEC. I'm trying to think if I have any Fusions that's DON'T have direct power servos in them-- and it might just be The Vanimal. I think...?
@@CrawlerCanyon Going to try first to 12 volt 35 kg SA66B //SA75 12 volt ..cant wait to see numbers on SA75...
@@tomandrews5392 I've got a lot of confirmation bias behind me when it comes to the SA75, because before the "supply chain related price hikes" it was my #1 favorite 3S-direct servo. Quick and quiet. I think as long as it can pull over 500oz I won't be disappointed. If it hits it's spec'd ~625oz, I'll be ecstatic.
So I’m really confused on how you keep saying it’s this much KG per cm. 1 inch has 2.54cm which I’m guaranteeing you already know. Your using 25mm servo horn then it would be that much kg to 1inch or 2.54 cm. I’m not understanding why you keep addressing it how you do when that’s not the case. Maybe you should also dedicate some Vanquish servo horns to this cool new project of test.
I test at the (from my understanding) standard 1 inch from the output, record the result in oz/in, then divide that number by 13.88-- which gives kg/cm. I didn't make the formula up, that's the formula. Well, it's actually divide by 13.887386556746, but we're not going to Mars, so 13.88 will suffice. So 500oz/in / 13.88 = 36kg/cm.
A 500oz servo "only" makes 3.53Nm, so we won't go into that. Newton meters mean nothing to us! 🤣
So what did you learn today? That's right, don't buy cheap garbage Amazon horns. When you run cheap crap horns they fail on the trail. You wanna run big boy servos, run the horns too
We can't put all the blame on $2 horns-- I've stripped out more than one each from Vanquish, Reefs, and ProTek. That's why I use (almost exclusively) $2 horns. Because when one gets rounded out, big deal. I stripped 2 Vanquish horns in one week-- and that STILL hurts.