Model Boat Mayhem

The Shipyard ( Dry Dock ): Builds & Questions => Yachts and Sail => Topic started by: Klunk on May 02, 2011, 05:29:12 pm

Title: sail drum - advice reqd
Post by: Klunk on May 02, 2011, 05:29:12 pm
I have a robbe Atlantis, sails ok but..........I need extra length to get the sails out. Also with the servo fitted, I think there is also room for speed improvement.
At present it has a hitec 785 drum winch, which I want to
a speed up
b make the drum winch bigger to give me extra rig length

I dont want to break the bank here....is it possibl to do the speed? is it possible to buy a larger drum, if not make one??
would it be better to go for a different servo all together????

your advice  is appreciated
Title: Re: sail drum - advice reqd
Post by: exvtop on May 02, 2011, 06:20:16 pm
klunk,

www.sailsetc.com (http://www.sailsetc.com) do a 100mm diameter drum for a HiTec winch - item 67f.

Not particularly cheap though.....

Mike
Title: Re: sail drum - advice reqd
Post by: Klunk on May 02, 2011, 07:14:06 pm
must be me.......but that has to be the worst site I have ever seen.
no search function obvious, confusing, over complicated, and cannot find the part you mentioned!!!
Title: Re: sail drum - advice reqd
Post by: Klunk on May 02, 2011, 07:24:03 pm
found it!!!!!!!!!!!
how much!!!!!!!!!!!!
gulp!!!!!!!!!!!!!!!
more than the servo itself!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Title: Re: sail drum - advice reqd
Post by: omra85 on May 02, 2011, 08:26:59 pm
Hi Klunk
Try giving Servoshop a ring,
http://www.servoshop.co.uk/index.php?make=Hitec (http://www.servoshop.co.uk/index.php?make=Hitec)
they would be able to tell you if any other drum (ie 725) is bigger and will fit the splines.
I take it you haven't a small lathe. An aluminium drum to bolt onto the standard disc would not take long to make.

Cheers
Danny
Title: Re: sail drum - advice reqd
Post by: Klunk on May 02, 2011, 08:34:35 pm
fraid not, was going to try making one out of plastic though!
Title: Re: sail drum - advice reqd
Post by: Nordsee on May 03, 2011, 02:37:54 pm
Make your own, it is not difficult. The drum is of 6mm birch ply, cut out 2 discs  the diameter you require. Cut from 1mm ply 3 discs drum size plus2cm. Drill  approx 8mmhole thru the centre of 4 of them and a 4mm hole in one. Make a sandwich of the discs, thin thick thin thickthin. Either screw to the top of existing drum or use a servo disc that fits the splines of the Winch. Not very well described but you should get the general idea.
Title: Re: sail drum - advice reqd
Post by: Richard M on May 03, 2011, 05:36:35 pm
Hi klunk

I am using the same winch in my Atlantis and I had to reduce the travel using the transmitter programming feature to get the correct sheet travel of 300-320mm. I suggest you consider why the servo is not rotating enough times. Are you using a stick with spring return? If so, you may be losing 50% of possible turns. Alternatively, has your tx channel been programmed to less than 100% travel?

I don't have an answer to speed of rotation except to say that I have not noticed an issue myself when sailing. I really don't believe that you need to change the drum.  I also think the Robbe instructions are wrong in suggesting removal of the drum centre divider.

RichardM
Title: Re: sail drum - advice reqd
Post by: tony23 on May 03, 2011, 06:09:44 pm
I'll be using an RMG Winch on my Atlantis it's expensive but you get what you pay for!
Title: Re: sail drum - advice reqd
Post by: Klunk on May 03, 2011, 06:42:46 pm
its a standard winch  (continuous loop) on the drum in the servo box. not big, will have to check how mant times it goes round. the tx is on pull down only, no ratchet.
Title: Re: sail drum - advice reqd
Post by: JayDee on May 03, 2011, 06:44:33 pm
Spamcanman,

I have just fitted a RMG winch to my J Class, my God its powerful and very fast too.
They suggest putting a "weak link" into the sheeting, now I know why !!

The winch is the 380EH, chosen for the sheeting length on the boat of 33 inches.

Be very careful when setting the winch up, all that power could cut fingers off, as
well as a lot of damage to your boat !.

John.  :-))
Title: Re: sail drum - advice reqd
Post by: tony23 on May 03, 2011, 10:41:02 pm
Hi John,
           I think you have gone a bit OTT with a 380EH I use those on my 'A'class yachts I know your 'J' class is large but I would have gone for the RMG280EL it's a bit cheaper the speed can be adjusted to suit and it's high torque. I only use RMG's so I don't notice the speed although I sailed a boat the other day with an Eurgel winch and it was painfully slow!

Title: Re: sail drum - advice reqd
Post by: tigertiger on May 04, 2011, 02:53:49 pm
Cheap servos are slower. Hitec are cheap, powerful and reliable, but slow.
Faster servos and winches cost.

As said, bigger drums cost more, but you can make your own. I have seen CDs used as the plates.
Bigger drum will speed things up, provided the servo has the torque to handle the extra diameter/pull effects.
Title: Re: sail drum - advice reqd
Post by: Jimmy James on May 14, 2011, 08:35:59 pm
One chap in our club uses Strimmer (Grass cutting) drums and fishing tackle reels on his sail winches ---He bolts them on to a 4 armed servo arm ----works fine
Freebooter
Title: Re: sail drum - advice reqd
Post by: aslo44 on May 22, 2011, 07:41:55 pm
must be me.......but that has to be the worst site I have ever seen.
no search function obvious, confusing, over complicated, and cannot find the part you mentioned!!!
Your right about the site though it's a wonder they sell anything through that vane, worst site I've ever used.
Title: Re: sail drum - advice reqd
Post by: tony23 on May 22, 2011, 10:40:41 pm
Your right about the site though it's a wonder they sell anything through that vane, worst site I've ever used.

Possibly, but sailsetc are the biggest selling shop in the World for model boat racing parts so something must be right!
Title: Re: sail drum - advice reqd
Post by: tigertiger on May 23, 2011, 10:54:07 am
Sails etc.

Poor website, great service, and fantastic knowledge of sail boats and everything they do.

Design thier own hulls and the boss (possibly ex-owner as I think he retired) a world champion.
Title: Re: sail drum - advice reqd
Post by: JerryTodd on May 28, 2011, 04:11:19 pm
My boat has two winch servos to control the braces; one for the fore mast, the other for the main & mizzen combined.  The drums are made from .1 inch PVC sheet and compact disks with the X servo horn that came with the servo attached to the bottom.

Each section of the drum is a different diameter to correspond to the different size yards being controlled.  The drum for the main brace, for example, is 4 inches, while the fore tops'l yard brace is 2.5 inches.
Title: Re: sail drum - advice reqd
Post by: tony23 on May 29, 2011, 07:52:04 am
Sails etc.

Poor website, great service, and fantastic knowledge of sail boats and everything they do.

Design their own hulls and the boss (possibly ex-owner as I think he retired) a world champion.

Graham Bantock did have the business for sale but he's still going strong running the shop and sailing this week in the IOM World Championships in the UK with his own design yacht a Pikanto.  :-)
http://iomworlds2011.wordpress.com/