What the newest cheap servo hotness?

[Jim85IROC]

JX is junk. Mine ran only last few minute and glitch and glitch only. Luckily got my refund back from HobbyKing. I will never buy this brand again.

Sent from my iPad using Tapatalk

Having problems with 1 unit doesn't mean the whole brand is junk. It only means the specific unit you bought is junk. The highest quality brands in the world toss a dud out the door from time to time. When you're dealing with inexpensive Chinese made crap, a LOT of duds get built. That doesn't mean that JX is any less reliable than any of the other equivalent cheap Chinese brands. If you swear off a brand over 1 bad part, you're going to run out of brands to choose real fast.

 

[mikemcE]

Or stick to good units with few if any failures, of course you do pay for them.


Hang up and Drive

 

[durok]

Mike's thinking about Promodeler again... Kick-Ass servo for the money... Awesome support if you ever need it, which is not likely!

 

[Hydrocarbon92]

If I'm not mistaken, every 5th post in the Promodeler thread is about a failure or problem lol. Luckily my only probs with JX have been from testing beyond the limits.

JX is junk. Mine ran only last few minute and glitch and glitch only.

What UBEC were you using? One thing I noticed with their 20kg servos is they don't like to be underpowered. With 1 on a Hobbywing 3A clone it acts up when you twist it fast, with 2+ they freeze for a few seconds then reset. When you add a cap buster, the freezing goes away. What's odd is they instantly unfreeze if you insert the capacitor.

When I power the same 3 from a 12A max UBEC at 7.4v, they work like champs. Yours potentially needs 2x the power, so I wouldn't expect it to work with less than a 5A continuous UBEC.

 

[mikemcE]

If I'm not mistaken, every 5th post in the Promodeler thread is about a failure or problem .

Well you’re mistaken !
I’m only aware of one failure, that was replaced.




Hang up and Drive

 

[Teng]

What UBEC were you using? One thing I noticed with their 20kg servos is they don't like to be underpowered. With 1 on a Hobbywing 3A clone it acts up when you twist it fast, with 2+ they freeze for a few seconds then reset. When you add a cap buster, the freezing goes away. What's odd is they instantly unfreeze if you insert the capacitor.

When I power the same 3 from a 12A max UBEC at 7.4v, they work like champs. Yours potentially needs 2x the power, so I wouldn't expect it to work with less than a 5A continuous UBEC.

Thank you Hydrocarbon92 for replies. I actually direct taken the power from my ECS as I was using 4S on my Wraith. Maybe it was the just a bad batch I got. [emoji4]


Sent from my iPad using Tapatalk

 

[Hydrocarbon92]

It could be either, electronics are the most mysterious of problems. Most ESC's are about 3A using linear BEC's, some better will list a "switch-mode" BEC that can be 3-5A and possibly more capable. I know I am reeeeeally hoping this Henge I got pans out well.

I will say it was nice of Hobbyking to give you a refund during a crappy situation.

 

[dweano]

When I power the same 3 from a 12A max UBEC at 7.4v, they work like champs. Yours potentially needs 2x the power, so I wouldn't expect it to work with less than a 5A continuous UBEC.

You got a link for that? I have a 8A 7.4V Bec running two JX servos...but more A is better!

 

[Hydrocarbon92]

https://www.ebay.com/itm/HENGE-5v-6...166222?hash=item2ef208ea8e:g:lFYAAOSwsTxXkdPb

The actual chip used is rated for 8A continuous & 12A peak, but it would probably get hot after a while. Also it is turned ON by removing that black loop on the right, I de-soldered the pins completely.

With a well-placed resistor you can adjust the voltage. I put a 50k 20-turn pot with another 10k resistor in series and I can go up to 5.8v/6.9/8.4v with the different jumpers. The 10k is just to prevent too little resistance as it's a voltage divider circuit, lower will allow over 8.4v output.

 

[dweano]

Ah nice. Thats actually the bec I have right now. I run two of these servos off of it:

https://www.banggood.com/JX-Servo-P...180-High-Voltage-Digital-Servo-p-1074872.html

Seems to work. Maybe bogs down sometimes. I should probably add a capacitor or something. I desoldered my pins too. Hard soldered it to the 7.4v setting. If I wanted to permanently latch it to 8.4V I would put a 60K ohm resistor there?

 

[Hydrocarbon92]

I just measured it and 13k6 brings it to 8.4v exactly and 10k is over 8.6v. I calculate 15k would be around 8.25v, and anything over 40k is near the base 7.4v. That's in parallel to the existing resistor not in series, so you'd need 1745 ohms if you removed/replaced the original. With

It's good to know with those servos, I was considering 2 on my 4ws Wraith. Not sure I really need extra power in the rear.

 

[Hydrocarbon92]

I just received the Kingmax servo and I'm mixed on it. Seems as powerful as the JX 6221 at 6v but slower. You'd need to use 8.4v to equal the 6221's speed at 7.4v. Incredibly slow vs the JX 5932 that's just $10 more. The upside is it has much finer resolution or steps than the 6221 & waterproof seals.

In other words 6221 beats it in price, Kingmax is great for a waterproof servo, and the 5932 beats both in speed & power.

I'm now going to fab up a fixture to test servo torque. Then I'll get an idea what these servos actually have for balls.

 

[Bbknucks]

The 6221 I had failed so I swapped in a powerhd wp servo I had. It works ok but noticeably slower than the 6221.

I ordered a 5932 to try out. Will be nice to not have a bec

 

[StomperCrawler]

The 6221 I had failed so I swapped in a powerhd wp servo I had. It works ok but noticeably slower than the 6221.

I ordered a 5932 to try out. Will be nice to not have a bec

Under what conditions did the 6221 fail? What voltage were you running through it? Any water damage? 2.2 weighted wheels? 10 lb rig?

 

[thewildblue77]

Well my "expensive" absina combat Acs1620BL servo started playing up last night...struggling to turn left to right on carpet....so Ive whacked in one of my spare 6221s and ordered a JX5932 which is supposed to be 32KG@ 8.4v.

Has anyone tried these out...worked out at about twice the price of the 6221... £17

 

[Hydrocarbon92]

Here's a vid showing both the JX 5932 and the 6221 on the same vehicle. Note the linkage is connected for 50% less throw. This is just 6.6v, and it's pretty insane for a $25 servo. I had to avoid moving the stick too fast otherwise it looks like the servo has jerky movement. It's actually smooth when you move the stick slow.

https://www.youtube.com/watch?v=QBV9ZADwU0A

 

[thewildblue77]

Im going to be putting 7.4v through it...it will be on a MMX, so I can go to 8v but Im using a 6221 as my gear servo....or will I be alright with 8v ?

Just got to wait for my banggood delivery now...

 

[JatoTheRipper]

Here's a vid showing both the JX 5932 and the 6221 on the same vehicle. Note the linkage is connected for 50% less throw. This is just 6.6v, and it's pretty insane for a $25 servo. I had to avoid moving the stick too fast otherwise it looks like the servo has jerky movement. It's actually smooth when you move the stick slow.

https://www.youtube.com/watch?v=QBV9ZADwU0A

Those JX servos look exactly like PowerHD to me. You can get them on eBay and shipped from within the US for fast delivery.

 

[Hydrocarbon92]

Looks aren't everything. The comparable Power HD seems to use a motor & gearing closer to the Kingmax I have. The vid below shows their $21 (Amazon) servo on 2S and it's really slow. For a few bucks more you can get the JX 5932 and it's MUCH faster at just 6v. It's got the reinforced case that uses 2 extra screws in the top. It lends itself to conformal coating - the pot screw is easy to access and the whole board & motor come out as one. As long as the gears hold up I'll definitely be buying more.

https://www.youtube.com/watch?v=iSHgMicVXWo&t=524s

 

[durok]

Additional cheap servo hotness... Yeah Racing now has red or blue waterproof 20kg servos for $27...4.8-6.6v