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Jakyat
01-09-2015, 11:38 AM
HELP!!! I am building an oilfield winch truck. I have designed a winch that runs off of 2 high torque continuous rotation servos. I am very satisfied with the pulling power of the winch, however, when I let off on the control, the servos will not hold the load. Maybe there is nothing I can do about this problem.
The servos are Hi-tec digital programmable, and I am running the unit with the spectrum 18 ch radio. I know there are lots of allowable adjustments that can be made through the radio, but I don't know where to start. I also have a hi-tec servo programmer, but I don't think that I can make this adjustment through the programmer.
Can anyone help me out with this?

Lil Giants
01-10-2015, 05:38 AM
There are esc's that have an electronic brake built into them, but the same technology may not be in servos too. I don't know for certain, but I would hazard a guess to say that you would have to gut the speed control within the 360 servo & connect it's motor to an outside esc with brake. I would also add the both servos on your winch could be connected to one esc, although motor wires of one servo be crossed compared to the other so both turn same direction.

trucker n
01-15-2015, 10:47 PM
If u look up heyok winch controller it has a drag brake on it plus it will also hold nuetral

Jakyat
01-17-2015, 12:58 AM
If u look up heyok winch controller it has a drag brake on it plus it will also hold nuetral

Appreciate the lead. I will research. Hoping it will work on digital servos and has ability to reverse rotation as i am running my winch with 2 high torque digital servos. Thanks again!! 😎😎😎

trucker n
01-17-2015, 08:09 PM
It is designed for winch servos they can make what u need

fhhhstix
01-17-2015, 11:14 PM
HELP!!! I am building an oilfield winch truck. I have designed a winch that runs off of 2 high torque continuous rotation servos. I am very satisfied with the pulling power of the winch, however, when I let off on the control, the servos will not hold the load. Maybe there is nothing I can do about this problem.
The servos are Hi-tec digital programmable, and I am running the unit with the spectrum 18 ch radio. I know there are lots of allowable adjustments that can be made through the radio, but I don't know where to start. I also have a hi-tec servo programmer, but I don't think that I can make this adjustment through the programmer.
Can anyone help me out with this?

The servo cannot hold center because it does not have a center point like a regular servo. It does not have a pot in it for position so it has no idea of what center is. For a winch to work right you need a mechanical advantage and you can achieve this in a couple ways.

1 a mechanical brake.

2 gear reduction such as a worm gear set up.

3 A mounted block and pulley set up so the direct pull is on the block and pulleys and not directly on the winch. This will also increase your pulling power as well.

Jakyat
01-18-2015, 11:29 AM
Fhhhstix, I had purchased the 2 servos from servo city and had them do the con-rot mod. They both have a little "pod" wired to them and hanging out. The "pods" have a little dial that has a centering point. Turning it one way causes servo to rotate one direction and visa versa. I dont know how or if that changes your theory.

fhhhstix
01-18-2015, 09:33 PM
Fhhhstix, I had purchased the 2 servos from servo city and had them do the con-rot mod. They both have a little "pod" wired to them and hanging out. The "pods" have a little dial that has a centering point. Turning it one way causes servo to rotate one direction and visa versa. I dont know how or if that changes your theory.

No all that is for is to set the dead band so it can be used as a continuous turn servo. If that pot you have was in the servo it would return the servo to neutral from either direction, the pot is hooked to the servo out put and that is the signal to return the servo to neutral. With the pot outside your setting the pot to neutral so you’re controlling the center point regardless of the position of the servo. You can make almost any servo continuous run by removing the pot inside like yours.

By not knowing how a servo works you were missled when they called it a winch servo. A winch servo is used for a sail boat where the winch never really holds a load or it is used with a block and pully system for holding power.

fhhhstix
01-22-2015, 07:11 PM
Check out these video's to help explain a continuous rotation servo and how it works. This should better explain what I was trying to explain.

https://www.youtube.com/watch?v=oXxq7LYRdYI

https://www.youtube.com/watch?v=nRfOCV_xu2s

Jakyat
01-22-2015, 07:39 PM
The servo cannot hold center because it does not have a center point like a regular servo. It does not have a pot in it for position so it has no idea of what center is. For a winch to work right you need a mechanical advantage and you can achieve this in a couple ways.

1 a mechanical brake.

2 gear reduction such as a worm gear set up.

3 A mounted block and pulley set up so the direct pull is on the block and pulleys and not directly on the winch. This will also increase your pulling power as well.
http://i1280.photobucket.com/albums/a491/Jakyat/Mobile%20Uploads/48AAAD54-FDB0-496B-A6C3-9689ACBEFB1F_zpsibqhpfdx.jpg (http://s1280.photobucket.com/user/Jakyat/media/Mobile%20Uploads/48AAAD54-FDB0-496B-A6C3-9689ACBEFB1F_zpsibqhpfdx.jpg.html)
http://i1280.photobucket.com/albums/a491/Jakyat/Mobile%20Uploads/186BB48C-66CA-4FF2-A2C4-11B6BAB7ABB6_zpsv5jwjwhu.jpg (http://s1280.photobucket.com/user/Jakyat/media/Mobile%20Uploads/186BB48C-66CA-4FF2-A2C4-11B6BAB7ABB6_zpsv5jwjwhu.jpg.html)
http://i1280.photobucket.com/albums/a491/Jakyat/Mobile%20Uploads/5AEDBEC9-54F2-4B30-8F45-D9F0B9D3F339_zpsljxdlacg.jpg (http://s1280.photobucket.com/user/Jakyat/media/Mobile%20Uploads/5AEDBEC9-54F2-4B30-8F45-D9F0B9D3F339_zpsljxdlacg.jpg.html)
Fhhhstix, i've attached a couple pics of my winch module. Obviously disregard the little winch. As you can see, my set up does have a mechanical advantage. Not much but it does. 24tooth pinion on the two drive servos. 48 tooth "spur on each end of the drum. The servos mounted in underneith on eitherside. I had purchased 2 hitec HS-7950TH SERVOS. 486.5oz-in.
I used this same servo as a steer servo on my crawler, and when power was on, there was no way i could manually turn or steer the wheels by hand. Power off...could easily turn them. That is why I fealt they would work great for this application.

Jakyat
01-22-2015, 07:47 PM
I have been researching heyok 4amp winch controller. Liking what im seeing so far. Allows you to get a little more power to the servos. More power means more pull. My concern is the way the brake works. I understand that the relay somehow short circuits the motor to activate the brake....not 100% just yet. Any body have anything to share on these controllers?

Jakyat
01-25-2015, 10:15 PM
Looking for opinions here. I have discovered something that may solve my winch brake issue. As mentioned earlier in this thread, i am using two cont-rot servos to run winch. each servo has a little pod wired in but hanging out of the servo. These pods have dials that control the direction of rotation. I have slightly adjusted each of these pods so that the servos are slightly working against each other in neautral. This puts both servos under slight load and they definetly hold the load.

Aside from extra draw on my battery, can anyone tell me if this will harm stuff. Keep in mind there is verylittle load on them.

Jakyat
01-28-2015, 10:15 PM
Hello all. I am still a newbie when it comes to radios and their capabilities. I am using my right joystick up-down (elevator??) to function my winch. I would like to be able to use one of the 2 position switches to turn the said channel off and on. Can anyone steer me in the right direction or post a link to an earlier thread that would help me out.

Lil Giants
01-31-2015, 03:36 AM
https://www.dimensionengineering.com/products/battleswitch

I think you can achieve cutting power to your servos with this switch wired in series with either the signal or black wire coming from the servos to the receiver. You would turn on/off with a 2 position switch on radio.

People use these battle switches to turn on/off lights, I use to use them too to turn on/off hydraulic pump before I had a sophisticated Spektrum computer radio to use ch mixing servos & esc's. I have one lying around that you can have to try, PM your mailing addy & I send it to you Monday. ;)