Topic: The infamous Motorflote ( Motorflotte ) push tug... (Read 374242 times)

NFMike · « **Reply #100 on:** February 22, 2015, 04:47:10 pm »

Quote from: U-33 on February 22, 2015, 02:19:35 pm

(just noticed I have a small bit of filing to finish off...)

Strictly speaking you have a lot of filing as a Kort nozzle has an aerofoil cross-section

Netleyned · « **Reply #101 on:** February 22, 2015, 04:56:14 pm »

Very true Plague. But
Does it really matter on a model
that is going to be used in water
and not sat on a pedestal for rivet counters?

Ned

Subculture · « **Reply #102 on:** February 22, 2015, 04:58:31 pm »

Depends on the application. Boats designed to shuttle backwards and forwards (like tugs) will tend to have a tubular profile with rounded off ends.

Boats intended for mainly forward direction tend to have an aerofoil section e.g. Speed rice profile.

I made a speed rice profile for an Aquabat sub I've been tinkering with for an eon. Did it more for looks than performance.

U-33 · « **Reply #103 on:** February 22, 2015, 05:20:25 pm »

If I remember rightly, my previous Motorflote had a piece of tube for a nozzle, same as this one is having. It went backwards as well as it did forwards, and sideways for good measure, there were no fancy tapered edges to the nozzle, just rounded off and that was it.

This one, being smaller than the other one, is quite likely to disappear up it's own nozzle...

Rich

Fastfaz · « **Reply #104 on:** February 22, 2015, 06:16:12 pm »

Nice job Rich,
I have a Kort nozzle on my Lowgarth but I did not fit the vertical piece onto the rear of the nozzle, it sails very well either forwards or backwards. Any comments on the benefit of having the added piece? i.e. will she steer any better.
Cheers,
Peter.

BarryM · « **Reply #105 on:** February 22, 2015, 06:36:10 pm »

Quote from: tugmad on February 22, 2015, 02:16:47 pm

Hi BarryM it is very common to have rounded tip props with Nozzles for instance the Avenger,Hibernia, Ionia, Sun XXV and Sun XXVI all had nozzles fitted with their original rounded tip type propellors retained. Geo

I think that explains it. Where nozzles are retrofitted, it probably would be false economy to exchange the screws. When a vessel is designed from the start with a nozzle, it would have close-fitting blades.

Barry M

NFMike · « **Reply #106 on:** February 22, 2015, 10:23:06 pm »

Quote from: Netleyned on February 22, 2015, 04:56:14 pm

Very true Plague. But
Does it really matter on a model
that is going to be used in water
and not sat on a pedestal for rivet counters?

Ned

Well, on a model the 'efficiency' of a Kort is probably immaterial, so I was assuming it would be at least partly for show.

The thing is that a Kort nozzle is shaped to give higher efficiency in the forward direction. A plain tube as this, and some other modellers are using, is not a Kort nozzle; just a prop in a tube. This Wikipedia article is quite informative and not very long: http://en.wikipedia.org/wiki/Ducted_propeller

U-33 · « **Reply #107 on:** February 22, 2015, 10:27:16 pm »

It will be on show here and there, but I very much doubt that the average rivet counter will know what a Motorflote is, let alone know what shape the nozzle is.

Rich

irishcarguy · « **Reply #108 on:** February 23, 2015, 12:54:53 am »

Actually the inner shape of the Kort nozzle is a venturi 'It works like this, as the propeller pushes water through it you get what is called a venturi effect & that reduces the diameter of the flow but speeds it up at the same time because of the aero dynamic shape of the Kort on the inside, increasing the speed of the flow through the nozzle. The better the prop fits in the nozzle the more water it can push through there by making it more efficient. This straightens out the flow as well as increasing the speed of the water passing through. This system is used on carburettors ( remember them ) to give exactly the same effect & also on race cars with their velocity stacks to gain the same advantage, it is a bit of a black art creating the inner aerofoil shape internally & is in most cases a closely guarded secret. So nothing is new under the sun. Mick B. P S -- I have made my own with some success, that too is a secret LOL.

Stavros · « **Reply #109 on:** February 23, 2015, 08:55:21 am »

Quote from: U-33 on February 22, 2015, 10:27:16 pm

It will be on show here and there, but I very much doubt that the average rivet counter will know what a Motorflote is, let alone know what shape the nozzle is.

Rich

Rich that is a VERY ARROGANT thing to say not at all in the spirit of mayhem

Dave

U-33 · « **Reply #110 on:** February 23, 2015, 09:15:03 am »

Excuse me? What did I say that's arrogant?

Rich

malcolmfrary · « **Reply #111 on:** February 23, 2015, 09:25:23 am »

Quote from: Stavros on February 23, 2015, 08:55:21 am

Rich that is a VERY ARROGANT thing to say not at all in the spirit of mayhem

Dave

Maybe, but very accurately put. A lot of the viewers probably never trouble to look at the back end, never mind the underneath bits, even when counting the rivets.

U-33 · « **Reply #112 on:** February 23, 2015, 01:02:56 pm »

Any ideas as to what these would be, guys? They look like D shaped brackets with a pin through a hole in them...would they be for attaching lifting hooks to lift the boat out of the water?

Rich

TailUK · « **Reply #113 on:** February 23, 2015, 01:06:59 pm »

Look like lifting lugs to me! Might also be used to attach sponsons to the side of the hull too!

U-33 · « **Reply #114 on:** February 23, 2015, 01:08:53 pm »

Never thought of that one, TailUK...good thinking. Thanks for that, much appreciated.

Rich

andywright · « **Reply #115 on:** February 23, 2015, 09:58:58 pm »

If they were for lifting, they would have metal going downwards along the line of pull, so i would say they are for joining another tug or sponson to the sides.

U-33 · « **Reply #116 on:** February 23, 2015, 10:01:54 pm »

Quote from: andywright on February 23, 2015, 09:58:58 pm

If they were for lifting, they would have metal going downwards along the line of pull, so i would say they are for joining another tug or sponson to the sides.

You mean like a vertical strengthening bar or a plate?

Rich

andywright · « **Reply #117 on:** February 23, 2015, 10:07:03 pm »

Quote from: U-33 on February 23, 2015, 10:01:54 pm

You mean like a vertical strengthening bar or a plate?

Rich

Yes, you may also find this interesting.
http://www.thos-storey.co.uk/bridge_relocation.php

Regards Andy

U-33 · « **Reply #118 on:** February 23, 2015, 10:13:04 pm »

Damn...no decent Motorflote pictures! I was all excited there for a minute

Rich

warspite · « **Reply #119 on:** February 24, 2015, 12:01:55 pm »

when i looked at these, first thought is that they are to lift the vessel out of the water for transporting to a new location - if this is a replica of an actual vessel - and its military so something they would do.

U-33 · « **Reply #120 on:** February 24, 2015, 12:32:57 pm »

Quote from: warspite on February 24, 2015, 12:01:55 pm

when i looked at these, first thought is that they are to lift the vessel out of the water for transporting to a new location - if this is a replica of an actual vessel - and its military so something they would do.

I don't think the military ever employed Motorflotes (although I may be wrong) they were designed for and used at Poole Harbour for moving pontoons.

Rich

TailUK · « **Reply #121 on:** February 24, 2015, 12:47:16 pm »

Not exactly the same as you were asking but similar.
http://www.tyneandwearmarine.com/services/modular-pontoon/

sailorboy61 · « **Reply #122 on:** February 24, 2015, 04:12:30 pm »

Its a motor unit and thats where its barges or whatever are attached. Doesnt look terribly strong, but then its not the biggest tug Ive ever seen.

U-33 · « **Reply #123 on:** February 26, 2015, 01:16:22 pm »

Just sort of wondering...is it feasible to extend a Springer hull with (say) 2mm styrene sheet to make it into a Motorflote? An 18" x 8" Motorflote would be a nice size, and still practical for me to lift and move about.

What do you reckon, guys...possible?

Rich

hmsantrim · « **Reply #124 on:** February 26, 2015, 02:35:28 pm »

Hi Rich.
when they jumboised tankers they just cut them in half and attached the bow and stern sections to the new centre section, so why not a springer.

frank

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Author Topic: The infamous Motorflote ( Motorflotte ) push tug... (Read 374242 times)

Stavros