Model Boat Mayhem

The Shipyard ( Dry Dock ): Builds & Questions => Navy - Military - Battleships: => Topic started by: tonyH on November 17, 2017, 08:41:30 pm

Title: Hydraulic propulsion
Post by: tonyH on November 17, 2017, 08:41:30 pm
Hello All,

I don't know if you've been reading the lifeboat build from Neil this was the warship alternative option from 1883, also from Mr Thornycroft. The pump had a 2'6" diameter.
Prior to this, in 1866, a gunboat was built, the Waterwitch with a 14' diameter pump, so there was some progress!

Could be another interesting project?

 
Title: Re: Hydraulic propulsion
Post by: Neil on November 17, 2017, 08:49:39 pm

this is quite fascinating..............one project is started and it opens up different avenues and variations on a theme......centrifugal powered water jets...................water jet power is nothing new..........just a variation on a theme.


go for it tony, it will make an amazing and thought provoking model.


neil.
Title: Re: Hydraulic propulsion
Post by: tonyH on November 17, 2017, 09:04:40 pm
Trouble is Neil, what comes first?

Is it to be the TB or the trawler? AND can I blame it on YOU!!!!!!!!!!!!!!!!!

 %%
Title: Re: Hydraulic propulsion
Post by: Neil on November 17, 2017, 09:40:07 pm

Trouble is Neil, what comes first?

Is it to be the TB or the trawler? AND can I blame it on YOU!!!!!!!!!!!!!!!!!

 %%


yes mate.........I've got very broad shoulders...........I originally was thinking the armed trawler.............but, and it's a BIG BUT........having built trawler models for years before I was a convert to lifeboats...............there is a great amount of detail on a trawler above deck, and I think that your build of a jet drive model would be overshadowed by the top hamper and detailing.


that torpedo boat looks a really nice boat, simple in detailing, a lovely shape and a very interesting concept.


even though I am a trawler lover, [ and that's why I jumped at the desire to see pics of that concept] I would myself, if I had to chose.....it would be the torpedo boat...........but only my choice.
Title: Re: Hydraulic propulsion
Post by: tonyH on November 18, 2017, 05:34:13 pm
Hi Neil,

Thanks for accepting responsibility :-)) but you're off the hook 'cos I've just found the following in Conway 1860-1905.

"Re: TB98.
 Built as an experiment to test the Ruthven 'turbine' (water jet propulsion by centrifugal pump), in a hull as similar as possible to the other Second Class boats (though the boiler had to be placed aft). Her speed compared badly with her sisters, manoeuvrability was 'disappointing', she had difficulty in going astern, and, worst of all for a TB, the propulsion made a noise that could be heard 10 miles away on a calm day."

I've still got to confirm this but it looks like the trawler is ahead on points!

I'll report further

 ;)
Title: Re: Hydraulic propulsion
Post by: Neil on November 19, 2017, 11:39:55 am

Hi Neil,

Thanks for accepting responsibility :-)) but you're off the hook 'cos I've just found the following in Conway 1860-1905.

"Re: TB98.
 Built as an experiment to test the Ruthven 'turbine' (water jet propulsion by centrifugal pump), in a hull as similar as possible to the other Second Class boats (though the boiler had to be placed aft). Her speed compared badly with her sisters, manoeuvrability was 'disappointing', she had difficulty in going astern, and, worst of all for a TB, the propulsion made a noise that could be heard 10 miles away on a calm day."

I've still got to confirm this but it looks like the trawler is ahead on points!

I'll report further

 ;)


that seems a fair enough reason for not proceeding tony..........but as an oddity, would be fun to take down to the lake with such a story...........magnificent..............only the Royal navy could make such a cockup as that, lol.
Title: Re: Hydraulic propulsion
Post by: tonyH on November 19, 2017, 12:29:30 pm
I know what you mean, so I'm doing a bit more research on the matter via Greenwich and the National Archives etc. I'll send you the stuff I've got so far on hydraulic propulsion via e-mail if you wish.

Cheers

Tony
Title: Re: Hydraulic propulsion
Post by: tghsmith on November 19, 2017, 02:32:02 pm
don't forget the U.S. howell torpedo, powered by a spinning heavy flywheel,, the torpedo actually performed well, the steam turbine that was used to get the flywheel spinning just before launching screamed like banshee, so much for stealth..  then again we invested a good chunk of shipbuilding funds on a ram vessel in 1893...
Title: Re: Hydraulic propulsion
Post by: tonyH on November 19, 2017, 03:24:52 pm
Aye, it's the graph of progress being nothing like a straight line.

That said, a lot of the stories could be read as 'fake news' for whatever reason. I've been reading a talk given by Mr Thornycroft himself from 1884 where the full (and inadequate) performance details are given but no mention of the noise, especially since virtually the same system was installed by his firm in the lifeboats 5 years later.

Oh Hell, I feel another 'Pointy Thing' coming on {:-{

Tony

Title: Re: Hydraulic propulsion
Post by: tonyH on July 28, 2018, 08:38:02 pm
Hi all,
This is by way of an update on the hydraulically propelled torpedo boat built by Messrs Thornycroft in 1883 and trialled the following year.
So this is the beast!
The full sized boat was based on the 63ft Second Class TB but lengthened by about 3ft and with increased draft to accomodate the extra displacement required and the model is built at approx 1:17.5 (don't ask) with a displacement of about 9lbs. Pump is the same as used by Ashley Needham for his model of Valiant (See August MB) with a mix of 28mm and 15mm plumbing.
 Forward/Reverse is controlled by a pair of home made flap valves via a pair of mini-servos. The servos were not installed when she was tested at Wickstead and the test was also hampered by a significant leak. The latter problem was sorted by flooding the pump room with a slurry of epoxy and micro balloons so she's dry now (In the bath at least)
I should be doing full tests next week and then, hopefully, I can finish off all the fittings.

Title: Re: Hydraulic propulsion
Post by: Umi_Ryuzuki on July 28, 2018, 08:46:21 pm
If the reverse valves are separately controlled, you should get some decent
maneuverability when in reverse.  ok2
Title: Re: Hydraulic propulsion
Post by: tonyH on July 28, 2018, 09:22:08 pm
That's the theory Umi!
One must is to have decent EPA on the radio so the flaps seat properly without upsetting the servos! Trial and error again %)