Model Boat Mayhem

The Shipyard ( Dry Dock ): Builds & Questions => Yachts and Sail => Topic started by: drover on April 16, 2013, 03:32:46 pm

Title: sail arm
Post by: drover on April 16, 2013, 03:32:46 pm
I am new to model boating and have made a start on building a racing sparrow. On the web site it is recommended to use a standard servo with an add-on sail arm. I must be looking in the wrong places as on doing a search all i come up with is sail servos. Where in the UK can I obtain an add-on sail arm?


Thanks
Title: Re: sail arm
Post by: hmsantrim on April 16, 2013, 03:45:12 pm
 
        Hi Drover.
                         here is the url you can click on to see servos with the sail arm attached ie (sail arm servos) and also the sail arm on
                        it own.  The sail arm servo usually has a higher torque than the std servo you would have as on the rudder for
                         instance.
 
                                  frank .
 
                         http://www.google.co.uk/search?sourceid=navclient&hl=en-GB&ie=UTF-8&rlz=1T4GGHP_en-GBGB453GB454&q=sail+arm+servo (http://www.google.co.uk/search?sourceid=navclient&hl=en-GB&ie=UTF-8&rlz=1T4GGHP_en-GBGB453GB454&q=sail+arm+servo)
Title: Re: sail arm
Post by: tigertiger on April 16, 2013, 03:50:25 pm
You can buy them but you need to get the exact one for your model of servo. I had problems fitting a Futaba X servo arm to a Futaba Y servo. It fitted but actually slipped on loading.


You can easily make one. Simply use a flat piece of plastic (e.g. a cheap ruler or perspex scrap).


Drill a hole in the middle, so that the servo hub/spindle has clearance. Then attach the plastic to the servo star with self tapping screws or small nut and bolts.


Martin did something similar here [size=78%]http://www.modelboatmayhem.co.uk/forum/index.php/topic,4231.msg41030.html#msg41030 (http://www.modelboatmayhem.co.uk/forum/index.php/topic,4231.msg41030.html#msg41030)[/size] reply #6. His is a two sided arm, but you can do one sided.
Title: Re: sail arm
Post by: Netleyned on April 16, 2013, 04:00:46 pm
Hi Drover
I made my own from a rule as did martin.
I have an arm exactly like the black one on Martin's photo.
PM me your address and I'll pop it in the post for you.
Don't put your address on the forum but in a private/personal message to me.


I have just looked at the plan and if you are building the RS 750 the arm needs to be
12 cm long to give you the throw needed for the sail sheets.
The one I have is only 8cm. 
Sorry.
Easy enough to make one as described by Tiger Tiger
Title: Re: sail arm
Post by: mrpenguin on April 16, 2013, 11:45:04 pm
You may find something at HobbyKing - something like this perhaps?
http://www.hobbyking.com/hobbyking/store/__10073__Carbon_Fiber_servo_arm_108mm_2pcs_bag_.html (http://www.hobbyking.com/hobbyking/store/__10073__Carbon_Fiber_servo_arm_108mm_2pcs_bag_.html)
Title: Re: sail arm
Post by: tigertiger on April 17, 2013, 01:50:04 am
You can buy them but you need to get the exact one for your model of servo.


I need to clarify here. This only applies to the arms that fit directly to the servo motor splines.
The ones that screw onto the servo star (plastic piece that fits onto splines) do not have the problem I mentioned before.