Model Boat Mayhem

The Shipyard ( Dry Dock ): Builds & Questions => Working Vessels => Topic started by: Marty on July 15, 2007, 06:39:45 pm

Title: My Nordkap build
Post by: Marty on July 15, 2007, 06:39:45 pm

(http://i189.photobucket.com/albums/z199/mwesterho1/DSC00225.jpg)
(http://i189.photobucket.com/albums/z199/mwesterho1/DSC00249.jpg)

Current:

(http://i189.photobucket.com/albums/z199/mwesterho1/DSC00250.jpg)

Title: Re: My Nordkap build
Post by: Tug-Kenny RIP on July 15, 2007, 08:35:33 pm

Welcome to the club Marty.  That's a nice piece of workmanship there.  I have not come across a chain driven tiller before.

Keep posting the pictures.  I'm interested to see more.

Cheers...Ken

Title: Re: My Nordkap build
Post by: Peter Fitness on July 15, 2007, 11:27:19 pm

Looking good Marty. I have often thought of having a go at Nordkap, so I would also be interested in seeing more photos. Chain driven rudder is new to me too.
Peter.

Title: Re: My Nordkap build
Post by: Martin (Admin) on July 16, 2007, 09:28:08 am

Yes the chain drive rudder does stand out and it looks like it's "geared up " too, should give you about 180^o movement!

Title: Re: My Nordkap build
Post by: Tug-Kenny RIP on July 16, 2007, 10:08:17 am

No levers to jam against the hull.  I wonder if it could be connected to Two tillers ?

Ken

Title: Re: My Nordkap build
Post by: kendalboatsman on July 16, 2007, 11:20:10 am

Quote from: Tug---Kenny on July 16, 2007, 10:08:17 am

No levers to jam against the hull.  I wonder if it could be connected to Two tillers ?

Ken

Hi Ken,

You could use it on a twin rudder setup, you would set up one rudder as in the photo above then a second chain between the two rudder posts. Watch out for excess load on the rudder shafts, maybe use a top bearing on the first rudder post to stop it pulling over with the sideloading.

Clive :)

Title: Re: My Nordkap build
Post by: Marty on July 16, 2007, 06:08:28 pm

Hi,

The chain driven rudder has indeed about 180 degrees of possible movement. I can still change the ratio’s if this turn out to be a bit too sensitive on the controls. The chain is equipped with a static tensioner in form of a stainless steel rod (small leftover from the driveshaft) pushing against the chain. With some grease lubrication wear on the chain won't be much of an issue I think.
The idea of a steering system with a chain is something I came across while browsing on the net. I liked the idea so much I use it in my Nordkap. My inspiration: http://www.boatnerd.com/model/tug/kilkenny/ (http://www.boatnerd.com/model/tug/kilkenny/)

I choose a chain (instead of a belt in case of the little tug) because belts have the unwanted tendency to dry out and/or slip under strain. To built this chain driven rudder control I used the “Chain – Power set 1-1378” from Robbe. Because the clap-gearwheel combination on the rudder shaft had more slack than I considered acceptable; I glued the clap to the gear with a dual compound contact adhesive. But no more unwanted movement there  It’s still removable from the ruddershaft though, so changing gear ratio’s is still possible.

Some more picures:

(http://i189.photobucket.com/albums/z199/mwesterho1/DSC00224.jpg)

The chain tensioner is clearly visible here:

(http://i189.photobucket.com/albums/z199/mwesterho1/DSC00262.jpg)

(http://i189.photobucket.com/albums/z199/mwesterho1/DSC00264.jpg)

Title: Re: My Nordkap build
Post by: Tug-Kenny RIP on July 16, 2007, 10:37:41 pm

Yes. it's a smart piece of engineering. I shall certainly try that on the next boat.

Just an observation with mine .... I set the swing of my servo to dead centre and secured the rudders in place.  Upon switching on the Rx the servos moved a little, putting the rudders off centre. 

When the Rx was switched off, the rudders returned to in line (straight ahead).  Does one adjust the rudder positions in the receiving mode. They would then move off line when switched off.  (I hope thats makes sense) 

Sorry to pinch your thread, but I also wondered how you adjust your chain system to get your rudder in line.


Cheers...Ken

Title: Re: My Nordkap build
Post by: Stavros on July 16, 2007, 10:42:27 pm

Yep set up in the recieving mode,well thats what I do and it seems to work!!!!!!!!!!!!!!!!! Stavros

Title: Re: My Nordkap build
Post by: Tug-Kenny RIP on July 16, 2007, 10:49:34 pm

Thank you Stavros.  Consider it done tomorrow.  I can always pull the rudder back by hand when I need to make her look pretty.  ;D

Cheers...Ken

Title: Re: My Nordkap build
Post by: dougal99 on July 16, 2007, 10:59:55 pm

My servos don't move when switched off but I always follow the following routine:

Switching on

                     TX first then RX

Switching off

                     RX first then TX


I have noticed that servos jump a little if the RX is switched on without the TX being on or the TX is switched off with the RX still on. The ESC can also be unpredictable in this situation, so I always follow the sequence above. I recommend it to the house...

Cheers

Doug

Title: Re: My Nordkap build
Post by: Martin (Admin) on July 17, 2007, 12:53:16 am

Be careful with the chain tensioner that you don't get metal to metal radio interference.