Kagama Kagama Servo Advice

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.
joefish

joefish

Well-known member
Messages
15
Reaction score
10
Points
63
Corally RC's
  1. Kagama
So I just recently killed my first servo in my kagama. It was just one of the cheap ds amazon servos, so I wasn't terribly surprised, and I decided to upgrade. I ended up installing an AGFRC A73BHLW 40kg servo, and so far it seem great (turns really fast even on carpet), tho I haven't had a chance to run it due to weather. I've been thinking a bit more about this choice tho and I'm worried it might be too weak/run too hot for this car. Have any of yall had experience with this servo or similar? I'd rather pull this and throw it in another of my rcs than kill it unnecessarily, but if it'll do the job no sweat I won't worry about it.
 
Definitely not a weak servo it’ll work fine agfrc in my rigs they

IMG_7289.webp


IMG_7504.webp
 
Awesome, thank you! I'm a little curious what the heat will look like at 8.4v, but im glad that i won't need to worry too much about killing it. (btw the 45kg looks beautiful, is that an A81BHMW?)
 
joefish said:
Awesome, thank you! I'm a little curious what the heat will look like at 8.4v, but im glad that i won't need to worry too much about killing it. (btw the 45kg looks beautiful, is that an A81BHMW?)
Click to expand...
Yes A81 in truggy A73 in buggy personally I don’t run @8.4v, they work fine & powerful enough @7.4v and less likely to overheat or burn them out.
 
I'll probably look into lower that voltage then as well, at least until i (potentially) grab an a81 and throw the a73 in my typhon. a random question, but are those carbon sleaves on your center braces or are they full carbon fiver?
 
PXL_20241006_143351835.MP.webp

The AGF 81BHMW is an excellent servo. Brushless, HV, Waterproof, Hall Effect potentiometer - steel gears. CNC body. Spec is on par with Protek - but half the price. 😎👍
 
Love the AGFs. Some of mine have been in 2 or 3 different rigs, over the past ~2 years, from 8s bashers to race buggys/truggys. Have yet to have one give up. I don't buy anything else.
 
phm14 said:
Love the AGFs. Some of mine have been in 2 or 3 different rigs, over the past ~2 years, from 8s bashers to race buggys/truggys. Have yet to have one give up. I don't buy anything else.
Click to expand...
The consensus seems to be that agf is great. I still might end up upgrading my kagama's servo to the a81 and putting the a73 in my 1/8 buggy, but that'd be more bc I just wanna be extra safe
 
Just an FYI AFRC servos are the same thing as AGFRC, I posted a teardown of one here:

https://www.rcgroups.com/forums/showthread.php?4689835-AFRC-D3623HBH-S-tail-servo-teardown

Clearly from the same factory with the same PCB with the same silkscreen and version numbers and has an AGFRC logo molded into the plastic gearcase bottom. Also the internals are quite good on these servos and I especially like the direct soldered pots and silicone goop applied to the solder joints on the main lead.
 
Stay away from PTK though, the PCB is tough but they have consistency issues with left/right throw and between individual servo examples (it's normal for individual servos to be slightly different but it's worse than usual). Also the soldering on the leads is atrocious. Some people use PTK servos in battlebots and they say they hold up to abuse pretty well, which is what I mean by the PCB is tough, it can stand being stalled and generally abused without releasing the magic smoke apparently.

https://www.rcgroups.com/forums/showpost.php?p=53384373&postcount=4

I bought a couple to see what they were like, they are totally unsuitable for swashplate servos but I used one as a steering servo and it actually works pretty well (the left/right throw consistency isn't an issue when its a single servo). But I needed to desolder and remove the PCB from the motor (didn't want to risk damaging the glued in motor by attempting to press it out) and resolder the internal leads apply electronics silicone goop and then put them back together. Absolutely not worth not worth it to save $20 when AFRC servos are $60.

EDIT To clarify, even with the three servo endpoints matched so that the throw was the same for all three and the swashplate was level at the upper and lower collective limit, the swashplate would wobble very slightly as you raise and lower the collective with these. It doesn't affect a steering servo but it makes them unsuitable for a helicopter swashplate.

EDIT most hobby servos have some variation in left/right deflection from center and compared to other servos of the same type because no two feedback pots are identical and there is also tolerance in passive components. The values on capacitors and resistors for example always have tolerance and the actual value rarely matches. Even hall effect sensors have some amount of variance. This could all be calibrated for but few hobby grade servo manufacturers actually bother with this.
 
Last edited:
Back
Top