Servo, Voltage and size

[mbvdl]

Hi everyone
I hope that it is ok for me to open a new thread, but this is something I feel is sort of specific and not really something I could search for.

I am still new in the crawler world, so my budget is very limited.
My AX10 RTC is still stock, and one area where I really feel changes are needed is in the steering. I have ordered the aluminium upgrade links, but now I am considering the servo thing too.

The AE1 esc is sucky, and since it doesn't have any drag brake anyway, I plan to put in my xl5 esc and reverse the motor (which will solve the quick reverse thing i think).

Ok, so the XL5 says "BEC: 6Volt 1 Amp".

Firstly, does this mean I must get a 6 volt servo, or can i use for instance this one (which says the oeprating voltage is 4.8V).
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=12451

How do I go about understanding the voltages and what can and what cannot be done.

Secondly, I don't know what 'sizes' to get, but I suppose the 40mm -B- size given is all that is important, as that is where the screws mount to the servo plate, right?

I hope to gain some insight on 'choosing a servo' from this. It's bad enough that I have to wait 6-7 weeks for an order from the states to here in South Africa, I want to choose the right stuff.

Oh, and will 15 KG suffice? Im sure thats already way more than the standard crappy AS1

Many thanks!
Marlon

 

[day215]

Marlon,
I'm sure someone else will chime in, but ill get things started. Your XL5 has an internal BEC that's rated at 6v, this would theoretically supply your rx and your servo with 6v too, there might be other factors that play into what your servo actually gets. Most use an external BEC like the one from castle, it can be set to a specified voltage by using the castle link.

The servo your looking at is rated up to 6v, it lists two specs, one at 4.8v and one at 6v, the more voltage the more torque, but don't go over 6v. Again, the adjustable BEC would let you dial it in to get the most from the servo.

I went from a stock axial servo, to a tower pro servo rated the same as the hobbyking servo your looking at. A quality servo rated at 200oz vs. a cheaper servo rated at the same 200oz, the better servo will typically outperform the cheaper one. I wish I would have saved the money I spent on the tower pro and just bought something substantial in the first place. I'm using a futaba s9157, wow what a difference a good servo makes! There are tons of opinions on what a "good" servo is, find your budget and do your research, but definitely go as big as you can. Any standard size servo should fit, I hope this helps"thumbsup"

 

[mbvdl]

It DOES help, thanks. WIth that advice, I realised the XL5 BEC is 6V and my stock axial servo is 5V, so that's out the door.
Ill do exactly that, budget and research!
appreciated day215!

 

[Charlie-III]

Here is a fresh "steering servo" thread to look over..... http://www.rccrawler.com/forum/showthread.php?t=236167

Likely there are others. Also look in the "AX10" forum here on RCC, there may be specific requirements/recommendations there."thumbsup"

 

[mbvdl]

Hey guys,
Many thanks for all the advice. And sorry to get back to my older thread, but it's a follow-up and related.
I got my new servo today. Savox, and loving it.
http://www.savoxusa.com/ProductDetails.asp?ProductCode=SAVSC0251MG&Show=TechSpecs

I just have a teeny last question or 2 before I shut up

The specs says 6V, and around 3000ma for stall current.
Its currently plugged directly into my receiver, which means im pulling directly off my ESC's built in bec (which is a stock Axial AE-1, which I think says the BEC is 5V 1Amp).
Is this OK? Do i really need to go for a bec? I want to put my XL5 esc in there, which is a 6V built in bec, but not if Im going to fry anything.

Im a bit lost on this matter still, but getting there.
Thanks again.
Marlon

 

[ghtpdm5]

i'd definitely go with an external, you'll most likely have issues with the ae-1 or the xl-5 cutting out while on the throttle and basically killing your steering while trying to do anything.

 

[WIDELOAD]

You will need an external, that Savox servo drawls 3amps at stall which is above what the XL5's internal Bec is capable of handling.

Best bet is the Castle Creations external bec (blue 10a one) its about the best around for its size.

 

[Charlie-III]

You will need an external, that Savox servo drawls 3amps at stall which is above what the XL5's internal Bec is capable of handling.

Best bet is the Castle Creations external bec (blue 10a one) its about the best around for its size.

+1 (to the previous 2 posts to mine)."thumbsup"

I have my CC 10A BEC connected directly to the servo, thus I take all possible issues out of what the RX can/can't do with the BEC power.

I had RX brownout issues before I added the BEC. I'm running a HiTec 7955TG steering servo on a Bully MOA.

PS, WIDELOAD....does your BEC sound like it's from the southern USA? I ask since you state it "drawls".......hahahahahaha

 

[WIDELOAD]

Nice catch Charlie, i didnt even see it when i proof read.

But nah, my BEC's from New Zealand 'Coz it choice as Bru'