How worthwhile is a winch servo?

[JoeR]

My father has an RC sailboat and uses a regular servo for the sail adjustment. I am curious as to how beneficial a winch servo is in place of this regular servo. Is it a worthwhile purchase? Thanks, Joe

[Climate]

A sail winch will give you more torque than a regular servo, as well as more movement. If you have a small boat (24 inches or less) a regular servo is fine. Anything larger would sail better with a proper sail winch servo.
Winches come in two general types, Arm winches and drum winches.
An arm winch is the same as a regular servo except it is a lot stronger, and will rotate more degrees from start to stop. Typicall y this is in the 120- 180 degree range.
A drum winch has a spool on the top of the servo and feeds line in or out by the spool rotation.
If you are sailing in winds over 10MPH a sail winch servo is a good investment as it will last a lot longer than a standard servo and the boat will sail properly due to to the sails being pulled in tight.

[JoeR]

Is a winch servo a drop in replacement if there is an arm servo in there right now? Or, are there mods that need to be made to use it? Thanks, joe

[Climate]

Sail winch servos come in lots of sizes.
Some are direct "Drop in" for the servo that is there now. Futaba and Hitec both have standard sized sail arm servos.
There are also "Quarter scale" sized servos which will require you to modify the mount a bit if you have a standard servo now.
Airtronics makes a sail arm that mounts a different way again.

I am guessing that your boat is in the 24-36 inch range.
Have a look at the Futaba S3801
The Hitec HS 815BB , HS-715BB I have used all of these servos on our demo models and they have been flawless.

Regards,
Peter
http://www.climateboatworks.com

[JoeR]

I am reasonably sure the Sea Dolphin from Tower hobbies is the model my father has: http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXUW96&P=0#tech

Not nearly as nice as the models you sell Peter. Maybe the next one.

How does the 3801 differ from the 3802 that Tower lists?

Am I to understand that you are recommending just getting a better arm servo rather then a winch servo?

Thanks, Joe

[Climate]

The term winch covers just about all types of sail control units available today.
If we want to break it down, there is the sail arm winch, and the drum winch.
For a boat like yours, a sail arm winch (A strong servo arm) is probably the best and easiest to install.
Drum winches are great in larger boats where extra travel is required. A sail arm winch is limited by the diameter of an arc the arm will swing, and the degrees through which it swings.
A typical servo will rotate 60-80 degrees from end to end. A sail arm will swing 120-180 degrees.
A drum winch turns the entire drum a certain number of revolutions.

[JoeR]

Thanks for the clarification Peter.

I have not been making the right distinction. drum vs arm not arm servo vs winch servo.

I will take your advice and get my father a good arm winch. I am learning ;)

I am fond of Hitech equipment and am looking at specs on the HS 815BB and HS-715BB

The HS-715BB looks huge (2.32" x 1.14"x 2.04" ) and only has a 40 degree rotation each side of center (80 degree total)? Am I reading that right?


The HS-815BB is smaller (2.59" x 1.18"x 1.26" ) and has a great deal of torque and 70 degree of rotation each side (140 degree total?)

Looks like the HS-815BB is the obvious choice then.

Thanks, Joe

[wolla01]

Hi, i have a International 1m radio controlled yacht, and i am having trouble with my electrics.
i have power, my batteries seem fine by my JR sail winch and standard servo for my rudder just make beeping sounds.
Do u have any idea what might be the problem.
or where i could go to get it sorted out?

[mfr02]

Check the battery voltage with a meter, both switched off and on. There should be virtually no difference - a difference indicates a dud battery. Check at the receiver power connection, both when something is being controlled and not. A voltage drop when work is being attempted indicates either a dud battery or wiring.

[twohl2]

I'm planning on making a 1;100 scale square rigger...I'm guessing that two strong winch servos would be enough to control it's sails?? (it's got three masts)

[beneteau3]

Just to give you some visual idea on large scale ships (1:24), take a look at the thread "Square Rigger Kit-18 Gun Brig-of-War of 1797" in this Sailboats category - These kits use three Hitec HS-815 HB arm servos and some builders are changing to Hitec HS-785BB winch servos. There is some discussion concerning both on the thread. Both types work very well- I have one of these models. If you do look at this Brig thread, I suggest you select "last page" and work backwards - it is a HUGE 90+ page thread!

[popeye163]

well need advice from u guy i bought a winch servo .i understand tat the arm type servo is easy to set up while the winch servo .when i need to unreel the tread it tend to mass up .then when i need to reel in the tread seem like it will go out of the real do u need any tensoner or guild for the tread.am i rite to say the arm type u can operate fast while the winch type u need to do it slow to prevent from uncoil into mass.pls advice tksv

[pompebled]

Hi Sailorman,

With the odd exeption, most drum winches operate a wire loop, which has a spring of some kind in it to keep it tensioned.

The leads going to the sails, are attached on that loop and are pulled in or let out when the winch moves the loop.

I don't have a picture at hand, but I'm sure someone else can provide one, making it visual for you.

Regards, Jan.

[Sea Devil]

What ever you decide to do don't buy from Servo Hut. They sold me a bum servo and refused to replace it and were rude and condescending during our correspondence.

[Dick L.]

advice tksv

Required Reading:
US 1 Meter Construction Guide (http://www.modelyacht.org/us1m/us1mcons.html)

It "should " answer all of your questions - doesn't matter what size boat you sail - pretty much a "Universal Guide"

[sailboat101]

How do I modify a Futaba S3801 sail arm servo so that it has 180 degrees of motion?