Model Boat Mayhem

Mess Deck: General Section => Model Boating => Topic started by: newbe7 on November 29, 2015, 12:38:52 pm

Title: Gearbox for paddler?
Post by: newbe7 on November 29, 2015, 12:38:52 pm
Looking to do a side paddler I found a place to buy plans and paddle wheels but have not found a spot or shop to build running gear be it belt or chain drive not sure if there would be a direct drive unit some where are there shops that sell components for hooking up motor to paddle wheel and what motor might be used for powering the paddle wheel.
Regards
Rick
Title: Re: Gearbox for paddler?
Post by: petermun on November 29, 2015, 02:00:09 pm
Try MFA Como,  Pete
Title: Re: Gearbox for paddler?
Post by: TailUK on November 29, 2015, 02:59:15 pm
I found a pair of Heng Long tank gearboxes (Delrin gears) on flea-bay for less than 12 quid complete with motors.  The output was at about 150 rpm which is a useful range for paddlers and there's loads of torque.
Title: Re: Gearbox for paddler?
Post by: newbe7 on November 29, 2015, 03:06:44 pm
Thank you for the links and information.
Rick
Title: Re: Gearbox for paddler?
Post by: Danny on November 29, 2015, 07:57:33 pm
Rick, I would recommend (based on personal experience) that you go for independent paddle drives.
If you are relying on only the rudder for steering, you will have virtually no slow speed control.  With a propeller, the water is thrust rearwards onto the rudder, which then deflects it, turning the boat. With paddles the 'drive' is a long way away from the rudder so only the forwards motion of the boat has any effect on the rudder, which is further compromised by both paddles trying to 'straighten' the boat.
As the hull is quite narrow, a pair of small motors will provide sufficient drive, say 400 or 540 size motors at most.  Gearing can be anything from cheap Meccano gears to integral motor/gearbox and belt drive.  Aim for paddle speed of 200 - 300 rpm.
Simple straight fixed blade paddles give less forward drive but are better in reverse.  Feathering curved blades are more powerful but lift the boat on one side when going 'one forward, one reverse', thus giving less drive on the 'high' side.
All good fun though ... its a battle of wits between you and the boat  {-)


Cheers
Danny


   
Title: Re: Gearbox for paddler?
Post by: Sandy on November 30, 2015, 05:25:23 pm
Not sure I would agree with that.

I wouldn't dream of building a paddle steamer with independent paddle drives unless it was the old RN paddle tugs (which actually did have independent drive).

The paddlers I know/have owned/have sailed have all been long, narrow and shallow draught. They may have large(ish) turning circles but what are you expecting from them as the originals were exactly the same. They won't spin on their own axis like a tug as they were never meant to do that.

The technique for coming alongside, as still demonstrated by the Waverley (the world's last ocean sea going paddle steamer - registered trademark) is to blaze up to the pier at speed and a fair angle, stop engines, whack the helm over to swing the stern then go astern to stop dead. Paddlers stop (and accelerate) way better than screw ships of similar hull form and displacement.

Independent drive is such a farf and the benefits really aren't worth it in my opinion.

All the best
Sandy
Title: Re: Gearbox for paddler?
Post by: John W E on November 30, 2015, 05:41:48 pm
hi Sandy

The way I understand the law for paddlers in the 'full size vessels' was only tugs were allowed independent paddles to give them greater manoeuvrability while berthing ships - passenger paddle ships had to have fixed drive paddles, due to the fact that a 'narrowness' of the beam of the vessel caused alarming roll when the paddles were used independently.   Tugs tend to have a greater beam and therefore more stability was actually pre-built into the vessel.

This topic is quite coincidental as I myself am in the process of cutting out paddle wheels for use on the Director Class tug.

I was thinking of using belt drives, courtesy of Como Drills but now I have seen the tank gear boxes which have been put on this thread - these may require further investigation by myself - and maybe a purchase to see what size motors they actually drive in these gearboxes.

Couple of pics of the process of cutting the brass wheels out.

Aye

john
Title: Re: Gearbox for paddler?
Post by: tobyker on November 30, 2015, 07:02:41 pm
Maybe, Sandy. I was on the Waverly (twtlsgps) when she hit Lochranza pier with a considerable thump - their technique can't really cope with wind!
I understand the law on independent drives was charged after not only alarming but fatal roll (capsize) on a trip boat on the South coast.
Title: Re: Gearbox for paddler?
Post by: John W E on November 30, 2015, 07:11:29 pm
 Hi have a look at this  :} :D
its from the  old MAYHEM  O0 O0  oh no its not you blind "xxxxx" :-)
put your glasses on next time Bluebird :-) {-) {-) {-)
http://www.modelboatmayhem.co.uk/forum/index.php/topic,51546.0.html

http://www.modelboatmayhem.co.uk/forum/index.php?topic=51546.5;wap2
john
Title: Re: Gearbox for paddler?
Post by: BarryM on November 30, 2015, 11:22:51 pm
Set-up in my Director Class.
BM
Title: Re: Gearbox for paddler?
Post by: derekwarner on December 01, 2015, 02:06:27 am
Well ..Sandy says......

'blaze up to the pier at speed and a fair angle, stop engines, whack the helm over to swing the stern then go astern to stop dead'

This appears to be rather universal....as our paddle Masters here in OZ us the same approach...even in our relatively narrow rivers ..... O0.... Derek
Title: Re: Gearbox for paddler?
Post by: Sandy on December 01, 2015, 06:35:52 pm
Just a toothed belt on mine:-

(http://i1248.photobucket.com/albums/hh499/sandymercer/Paddle%20drive_zpsivh0oazh.jpg)

Title: Re: Gearbox for paddler?
Post by: newbe7 on December 02, 2015, 12:12:45 pm
Thanks for the replies.
Rick