PDA

View Full Version : Hitek 645 servo



littledeuce
04-06-2008, 03:59 PM
Alright I just bought this thing and put it into my W/K and all I can get out of it is max 15 degrees either way. It hardly moves. Stk Radio and esc with an Integy 55t motor. The motor works great, lots of power and ALL batteries are fully charged. Nobody said a thing about having to upgrade any other components to make this work when I bought this servo.

Someone please help I'm really frustrated!!!!!:1zhelp:

Freeze
04-06-2008, 04:04 PM
You should be able to get 45deg in either direction. That is what they are rated for, 90deg in total, unless you have a 180deg version.

Have you tried it with the steering linkage off to exclude binding from the problem? Just a servo horn.

Were you getting 45deg either way with the old servo?

What radio are you using? Might be simply a setting there. Oop... just re-read... stock radio...

littledeuce
04-06-2008, 05:56 PM
Without the arm connected or with it connected it doesnt matter, no change. Trim settings on the radio have no change. With the old servo everything worked fine and no there isnt any binding

ecoli
04-06-2008, 08:30 PM
Without the arm connected or with it connected it doesnt matter, no change. Trim settings on the radio have no change. With the old servo everything worked fine and no there isnt any binding

Sounds like a bum servo. If other servos work fine, but this one doesn't best bet is to take it back or send it in for a replacement. Doesn't happen too often (I've never had problems with Hitec servos myself), but I have heard of it occuring before. Can't remember what the exact issue was, but I do remember it usually resulting in having to exchange/send it in for repair.

Use it as an excuse to upgrade to a 5955 ;)

Freeze
04-06-2008, 09:48 PM
X2 on the 5955...

Not bad prices on ebay either... just watch that shipping. Almost $50k to my place!!!
Yikes... hope that's a miss-calculation :)

http://www.mypetsquid.com/misc_images/Picture%202.png

HeyOK
04-07-2008, 08:13 AM
That's a picture worth framing! Wow, how are they shipping that?

EHeye
04-08-2008, 03:47 PM
In a 24ct gold box hopefully.

SeanD
04-25-2008, 05:25 AM
Sorry but I just happened upon this thread. Not sure if eveyrthing has been straightened out but if not . . .

The stock WK TX has a button/knob on it that controls the throw of the steering servo (not the trim) . It is used to put the truck in "trainig mode" - in other words the servo won't turn all the way so that you don't flip your truck. I found this out the same way - I thought I killed my servo until I found that the training mode knob was turned all the way into the "dummy" zone.

I know that you are saying that it worked with one servo but not another BUT its so easy to accidentally hit the training knob that is possible this is your problem.

Just a though.

Sean

EHeye
04-25-2008, 08:58 AM
Sorry but I just happened upon this thread. Not sure if eveyrthing has been straightened out but if not . . .

The stock WK TX has a button/knob on it that controls the throw of the steering servo (not the trim) . It is used to put the truck in "trainig mode" - in other words the servo won't turn all the way so that you don't flip your truck. I found this out the same way - I thought I killed my servo until I found that the training mode knob was turned all the way into the "dummy" zone.

I know that you are saying that it worked with one servo but not another BUT its so easy to accidentally hit the training knob that is possible this is your problem.

Just a though.

Sean

Mine did the same thing when I swapped mine over. Had to adjust the dummy knob thing. I forget which one it was. Don helped me out with it. :biggthumpup:

SeanD
04-25-2008, 11:10 AM
Glad its not just me who fell prey to the dummy knob :paranoid:

You think they'd put the restriction on the throttle and not the steering!! Not bad - they let you go full speed but hinder your steering so that you can't avoid obstacles!!! And the "dummy knob" is not dealt with much - if at all- in the manual!

canadianlimitededition
12-20-2008, 02:04 PM
here looking at an old post, but it may help me.
on my new ax10 the hitec 645 turns like crazy to one side but then shutters to the other, the tx and rx are a traxxas tq2

HeyOK
12-20-2008, 03:20 PM
It sounds to me like at least one of the transistors in the motor driver circuit has given up. If the motor turns fine in one direction but not the other and it isn't due to some sort of binding in the gear train, that's probably it. These transistors are usually surface mount things and are difficult to work on.

If you have another servo that has a dead drive train, you could try soldering its circuit board in there. HeyOk Performance could do this for you if it isn't up your alley.

canadianlimitededition
12-20-2008, 04:00 PM
it turns 90 degrees but it does not go to center. what or where is that adjustment . i remember seeing it somewhere but thats it. very vaque just like my mind

HeyOK
12-20-2008, 04:23 PM
it turns 90 degrees but it does not go to center. what or where is that adjustment . i remember seeing it somewhere but thats it. very vaque just like my mind

You're losing me. What adjustment? The trim? It is called various things depending on what transmitter you have.

You mentioned that you have a TQ 2 transmitter. There is a little knob above your left thumb called "Steering Trim" that you tweek to make the car go straight when you aren't turning the steering.

On more adjustable radios there is a setting called EPA (End Point Adjustment) to set how far the servo can travel. There is a mod you can do to the TQ 2 and TQ3 transmitters to emulate this, but I thought you wrote that the servo would only swing in one direction at normal speed, but then moves slowly (or jerkily [is that a word?]) in the other.

Sorry if I have confused the issue.

canadianlimitededition
12-20-2008, 09:40 PM
ok let me start from the beginning. cause i think i got myself confused.

the servo turns 90 degrees in total.
but to get full sweep lock to lock i have to turn the trim all the way to one direcion and then center the servo arm, it gets it real close.
i dont like that idea, i would like to have some area to adjust.
is there an adjustment on the pot? i think that is what they are called.
does that make more sense

HeyOK
12-20-2008, 10:25 PM
Sounds like you need a transmitter with end point adjustments.

canadianlimitededition
12-21-2008, 12:06 PM
i have tried other know good servos and they rotate the way they are suppost to. so i think that it possibly has a no good resisitor. but all my no good servos are different. only one has a small board but has only 2 wires to the motor not 3 like the hitec.
any other suggestions, or ideas?