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Dry Dock / Shipyard: Builds & Questions => Working vessels R&D: => Topic started by: rathikrishna on February 07, 2012, 04:07:33 PM

Title: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 04:07:33 PM
Good Evening..Friends..modelers..Colleagues..whenever we realizes, that we need some complicated mechanisms for our crafts, we have ample of options..most of them are buy from a local hobby store..but, sometimes we instantly realizes that our needed things are not on the list..and some times it may far beyond our reach because of the heavy price tag..then we corners, and think, ourselves as, oh..can do on other time..and some of us think, i will start to take over duty,and make money to buy it..and we will buy it somehow..but again realizes that that purchased unit is not much apropriate for own works..so, we will make a craft with a specification to the purchased material or stuffs..result..? a great desperated satisfaction..why..? and what for..? while we can make our own stuffs..

here i am working on my new tug, is a mini one, can hold in palm, but still she must be powerful, and yes intended to pull or push a big craft, with her's immense power..but because of the smaller size, it is not possible to fix a conventional shat system on this tug, even with a steeper angle..if so, there must not be any place to accomodate any battery and electronics..so..? only way to fix the power drive train in a vertical manner, and by avoiding the conventional rudder system.. :-)
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 04:17:15 PM
to avoid the conventional shaft prop and rudder mechanism, its, yes, correct, all we know that we need a thrust vectoring mechanism..means a unit that holds the propeller and its driving gear under the hull, and it must rotate from its pivot axis, for steering controls..so, to save time i looked in some known places..but the price list was too shocking..i realized that with that money i can make at least 30 to 40  1:28th scaled crafts..and from its specs i know it wont works to my standard..so, turning again to work table..

all you know, this is not my first thrust vector mechanism, but sharing it in detail, because some of my modeling Friends asking for some idea about a mechanism like this..its all cool..
it will be very goose fleshing, while we drive a car with world class engineering..we feel ample of excitement at that moment..if so, imagine we driving a car, with same performance, but, the entire car made by ourself..!! so exciting..!!

like that, we can make all needed things from things around us..most of the time we never notice the importance of the materials around us..and all it works for years..without any trouble..nicier than a commercially available one..and sheer satisfaction..and excitement..  :-))
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 04:29:56 PM
whenever we thinks about a thrust vectoring mechanism, we thinks about heavy magnesium or brass gears holding all in a water sealed pod..and makes it heavier and battery eater..but here you can see how simple is to make a perfect thrust vector mechanism, with handy things..all expalined things are only a key, and you can use any apropriate materials,with you..size..materials, motors all up to you..and one request..never consider these efforts, as because of my disability to buy anything, but if we buy all needed things then what will be our contribution in to our modeling..? so, we must research our own..again..again..at last sucsess.. :-)

here, according to my idea, the intented tug must be powerful..so, a fast reving prop with less angle is not a good mach..so, i have to make an entire unit for the purpose..including the prop..so, start..

all we know, a vertical thrust vector mechanism must contains two tubes, one is a holder tube, (most outer one) while the second inner tube is for altering the angle of steering, while a thirdth shaft, not tube is intented for driving the prop..briefly, steering and driving process happens simultaneously..

so wee need two tubes, that one holds the second one within..so, i turned to a ball point pen, and a piece of brass rod..to my experience a ball point pen body shell is very nice for most of the RC boat application..you can use anything apropriate to you, like brass tubes..carbon fibre..anything..
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 04:34:50 PM
the second thing in our need is driving shafts..you can use any rods..but i prefer the 4 mm bicycle spoke, as its one end holds the thread set up..makes even more easy..

when we think about toys..we laugh..but never under estimate the toys..especially about the silicon gears are far better in applications..lives longer..
so i scrapped some gears as crown wheels and pinions from toys..there is no restrictions in size and number of gears ...can use any type..but make sure its a crown wheel as we have to shift the angle of drive in to 90 degree...
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 04:38:06 PM
we can use any motor..type..or size..but here i have to make sure its a tiny one as possible..but with a high RPM..to get a high torque..

can also use any motor..an ECM..or MCM..
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 04:41:23 PM
now make sure that the inner tube is just free in outer tube..it must not be jammed, but make sure not too loose...

and make sure the drive shaft is not tight in inner shaft, but make sure not too loose...
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 04:43:59 PM
so..now we can see the two tubes and driving shaft in order...

in detail..
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 04:49:46 PM
now..we got the shafts...and tubes...now time to make prop..

as i said before, the craft must pull or push with great force with irrespect to the size of the craft..so, i made a prop greater in diameter..so, i purchased a aluminum vessel lid..for Rs 15/-

make three circles as shown..
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 04:53:49 PM
take a meat mincing scissors, and cut it with ease...

grind off any flashes all around and make the tip sharper as possible..and place it on a paper, the paper is with a marked circle, in 120 degree each, can be done with a simple protactor, from a school geometrical instrument box..mark all three angles..
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 04:56:56 PM
now the prop is in hand..but still not completed..as we have to bend the blades later..
now time to fix prop on shaft..
take a spoke nipple for the same spoke that we took earlier, and make sure the threads are sound..
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 04:58:53 PM
Ohh friends..will be back..Mom calling for medicines and food..she is anger on me..
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 05:31:37 PM
now split the spoke nipple in to two, as shown, while keeping the round base of the spoke as back nut of the prop..can be cut with a junior hack saw with a high speed blade on it..while holding the nipple on a vice. one of the benefit of using the nipple is, very ease of manipulation because of its sqare shapes at angles..can also use apropriate nuts..but, as the nipple is brass there are no rusts..

now insert the first piece of nipple at back, then prop then the balance piece as shown..
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 05:38:31 PM
can see the back side..
now time to bend the blades..Friends, you can bend the blades, according to the geographical natures of your place, as the corriolis effect affects on propeller, and here in my place it is feasible to bend it in to a direction, in to counter clockwise, while looking from the back side of the craft, as in my experience, a craft with prop rotating in to a clock wise direction, tends to lean to the ooposite direction in a long run..so final determination is yours..and please do not bend the blades too much at beginning, as we can bend it later to a great angle, if nessesary, and can achieve an optimum performance from set up..here, i avoided a foil like bending, because this prop is intended to work on both directions..as it meant for a tug..you can simply bend it with a nose plier..
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 05:47:08 PM
you can clean the tips and can sharpen the tips even more now as the tips are out off in an angle..a sharp blad bites water more easier..so low load at motor and good performance to a given power set up...
now carefuly watch the photograph, and see the simple brass piece is inserted between the crown wheel and prop, while leaving two galvanized washers to the side of the propeller, to avoid any tightness in shaft, with the inserted brass tube, in working pressure in either directions..this piece of brass tube is meant for to serve as a simple bearing..

now attach a second piece of brass tube as shown..hold it tight and make sure the angles are correct...
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 05:51:32 PM
see it closely...its all simple..
and attach some piece of stiff ( 104:12 type) foam board..as shown..use 72, or 76 grade cyano glue is cheaper as 30 Rs for a bottle..take extreme care while working as it can stick on any surface in fractions of a second than a domestic one..
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 05:54:25 PM
oh..connection is too slow..God..
some more close up views..see its nothing..but we feel some thing complicated..see..all simple..no..simplest..
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 05:59:14 PM
now make sure the free running of the gears..apply a little oil to it..not much as we have to paint it...
now..time to fix the mechanism on craft...take your craft..may be anything..and one of the privillage of this type of propultion is very quick response in steering, and less space consumptions..and also no loss of prop angling..

make an apropriate hole on craft with point iron, or with round file..insert the outer tube, the ball point pen body here..and make sure the positioning..
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 06:01:53 PM
glue it from inside..after cutting the tube for desired length..
now the mechanism on craft...
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 06:05:30 PM
you can see an added aluminum mesh above the gears to protect it from weeds and fishing threads if have any..
and time to paint..i sprayed it with copper cloud..metallic..while leaving the driving portion..
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 06:10:08 PM
now..time to fix the motor..see the simple set up..with same nipple..its easy..but works to a great standards...
one of the most unused part of a servo is a circular flange..so have ample of them..so can use it vigourously..
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 06:13:35 PM
so, all fixed..time to check out..will it work..? especially at high speeds and high loads..?
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 06:19:10 PM
yes sure..my testing longed about an hour, at lake, and she is far powerful, and at high RPM, she can even pull a scow..and well balanced also..added 200 grams of led weight..so perfect..see the test video of mechanism here..will add craft video as i finishes her by tomorrow..its my chubby tuggy..
http://www.youtube.com/watch?v=GBVQesvfeZ0
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 07, 2012, 06:27:41 PM
Friends..whenever we complete a craft we think we learned some thing..but we realizes still we are learning..making each craft is s new lesson..and innovations..are new..and we must contribute some from us..its sure..then only crafts lurks around us..to make some nice crafts we do not ample of money and a lifetime efforts..a little money for a lunch..and two or three evenings..one on water..or in land..or in air..and merging in sheer pleasure of RCyiiiiiiiiiinnnnnggggggggg..............woooosh...and wroooooms....so..come in all...make a lots of crafts..and RCyit..all.... :-) :-))
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: HawkEye on February 07, 2012, 09:40:47 PM
Krishna,
I thoroughly enjoy reading all your posts and would like to thank you for some interesting ideas that you put forward building these items.  :-))

HawkEye
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 08, 2012, 03:54:43 AM
Good Morning Hawk..its all simple..but effective..make a lots of crafts.. :-)) thank you..
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: tweety777 on February 08, 2012, 07:40:55 AM
Krishna,

I think you will find that you're model won't turn at all, or at least will hardly turn.
She will probably move sideways instead.
That is because your thruster is pretty much midships placed, and as there's only 1 thruster there is no momentum, and it's a momentum that makes a vessel turn.
You'll need to add 1 thruster (maybe behind or in front of the original thruster as moving the current 1 will probably be next to impossible), and otherwise you'll need to live with the fact that this model won't turn at all, in which case I would recommend adding a large rudder-like keel at the stern to keep her going straight, rather then being steered by the wind.
The second thruster probably doesn't need to be this big and powerful, as it's main purpose is to steer the vessel.
You could make a rudder with a small, but long motor in it with a propeller in a "tunnel" (don't recall the proper English name, it's basically a short tube around the propeller, it's mostly used in tugs as it gives a certain propeller some extra efficiency, and therefore more power), that would give it enough power to steer the vessel (though you'll need to keep the main thruster amidships when steering, as you'd otherwise steer whilst moving sideways).
Or a large rudder under the stern could do the job as well, though it must be placed as far to the end of the vessel as possible, but as it's not so much in the propellers thrust (especially not when turning) it needs to big as the rudder mostly needs the water from the propeller to give some steering power.
Therefore a propeller fitted to the rudder would give that much more result, though it does require 1 or 2 more channels on the radio.

Greetings Josse
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: MikeA on February 08, 2012, 10:35:43 AM
josse i think krishnas perpose of this thread is to demonstrate how to build a schottle unit and the boat is to demonstrate its operation.

krishna ive followed many of your threads but never commented on any of them seeing as you know what your doing not a lot can be said as far as help is concerned. i got a question for you:

how long does it take you to build a model? you seem to demonstrat a new boat every week!!

I got some challenges for you if your interested.

I challenge you to build a amphibious car!!

like this ww2 DUKW

(http://s15.postimage.org/epnn0kb5z/dukw.jpg) (http://postimage.org/image/epnn0kb5z/)

(http://s7.postimage.org/lax6wbl6v/dukw_diag.jpg) (http://postimage.org/image/lax6wbl6v/)

you up to it??
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: tweety777 on February 08, 2012, 10:38:26 AM
josse i think krishnas perpose of this thread is to demonstrate how to build a schottle unit and the boat is to demonstrate its operation.

In the first post I read something about this boat being build for pushing and/ or towing much larger vessels around.
Then it's a huge handicap to not be able to steer the vessel.

...here i am working on my new tug, is a mini one, can hold in palm, but still she must be powerful, and yes intended to pull or push a big craft, with her's immense power..but because of the smaller size, it is not possible to fix a conventional shat system on this tug, even with a steeper angle..if so, there must not be any place to accomodate any battery and electronics..so..? only way to fix the power drive train in a vertical manner, and by avoiding the conventional rudder system.. :-)

Greetings Josse
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: MikeA on February 08, 2012, 11:17:08 AM
touche josse
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 08, 2012, 02:57:41 PM
Tweety..give me a little time..need no any innovation..i will add a test video, of same craft, and a finished one also..thanks for the valuable advice..

Mike a million thanks for the challenge..and also willing to make an articulated amphibian..a million thanks again..but all will be after my presently working crafts..have 6 of them..once again..thanks for the challenge..and photographs..Goddess may bless us..all..have some nice crafts.. :-))
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: MikeA on February 08, 2012, 03:27:54 PM
6 models to build eh? so youl be finished by friday then :}
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 08, 2012, 06:13:07 PM
almost Mike..but back pain is disturbing me lots..still no time to be lazy..and also professinal works..and already started working on amphibian..making drive train..will complete it this night..thanks once again for the challenge.. :-))
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: MikeA on February 08, 2012, 10:18:08 PM
lol allready!! will it be fully RC? drive on land and water?
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: ayrshire andy on February 09, 2012, 01:00:01 AM
Knowing krishna it may perhaps take off as well!  :D
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 09, 2012, 04:22:16 AM
its sure..Mike..its a fully radio controlled one..in land and water as well..tested by erly morn..and waiting to replace wheels in to a little more bigger, as this used wheels are not big enough, in the transition to water from land..yes..working..but i need a little more ground clearance..and also willing to change the used motor for propultion..need more torque than RPM..and once again..you gave me a new vision in modeling..oye..oyyy...a million thanks once again..
Andy..thanks for the inspiration..its almost complete..and lokking in my text book for WW 2 cammouflages..
will add a test video of the "Chubby Tuggy" later..so..do not be lazy..make crafts..lurking crafts.. :-) :-) :-) :-))
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: MikeA on February 09, 2012, 08:27:57 AM
i thought it would keep you busy for at least a week!! not just an evening, youl eventually run out of ideas what to build krish, theres no prises by the way but you can have a pat on the back if you like :-))
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 09, 2012, 11:33:46 AM
thank you Mike.. %%
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 09, 2012, 12:08:27 PM
Friends..by reading the opinion of my Friend Tweety,  i can think, why 80 % of modelers stay away from model making..its clear, that all we over estimate our needs when we decides to make a craft..so, whenever i thoughts about a craft to make, at first i dreams about its propultion and stability..the ideas, from last, 36 or more years of my experience come in to play..while i thinks about a craft..in my child hood it was a great head ache to me to stabilize a plywood piece over water, especially it as it is my boat..so i found some remedy..on that time, about the age of 5, i can simply imagine its far beyond reach of an average boy..so, i always thanks to my Pappaji, Dr Ramakrishnan Keeriyaatt, for the corrections..and innovative ideas..he, my Pappa taught me that, whenever we think about to make a system, or a machine, we must think in various ways for a same results..and we must workout some researches with our mind..and it always workes..

so, actually i was looking for more craetive and extra ordinary crafts all over, it was accidental, that i saw a little tug in our Mayhem..and i clearly know, such crafts are too unstable because of its nature of the hull..so, give up..?  never..as it is not an option..so i recalled many things deep from my " old compressed files" within the storage place of my brain.. %%
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 09, 2012, 12:18:51 PM
so, all we know, how to make a hull with a super stability..so i applied it simply here..when i started to make hull for this craft, the idea was clear about its shape, propultion and weight..and yes she is designed for tight maneouvers instead of a high speed long chase..so, it must turn..from a stand still..its a must..and also she must be powerful enough to pull or push a heavy load..because, this one is designed for my new quay side, that i am building on my backyard..it will spread over 3.7 cents of land..behind my little home, that home constructed by me myself from foundation..the quay side will be equipped with rail road, road, canals, and all other things including a solar and wind power house..so, she will be the key of controlling my quayside..so she must do well..

then, will she..? will she turns well..? or as told by my Friend Tweety..as "Krishna, I think you will find that you're model won't turn at all, or at least will hardly turn."..?

no chance Friends..she must turn..
see here the test footages.. :-))

test footage 1...

http://www.youtube.com/watch?v=VS1OVpDIn5w


Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 09, 2012, 12:28:46 PM
test video  2... %%


http://www.youtube.com/watch?v=W7LXm-eg4ZA
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 09, 2012, 12:31:21 PM
test video 3...

http://www.youtube.com/watch?v=W3Kkf9uDsNk
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 09, 2012, 12:42:07 PM
Friends..i posted it all here not to show some thing about me..but think how nice about the craft..and we do not need any ample of knowledge in extreme engineering to realize a stunning craft..usually we, under estimates ourselves..and stays away from making models..its all simple..and we need only two dry cells and a toy motor to make a boat..it will run nicely..instead we think about a motor that eats about 20 amps in run..and yes 80 % of the power is wasted as cavitation and splashes..with a mere 3 amps a 2.5 feet long craft will fly over water..and a self research also gives us ample of experience in model making..so..once again..modelers..come in..all needed materials are around you..look around..take it all..and make it all..tugs..warships..speed boats..cruisers..tow boats..life boats..ocean liners..scows..anything..and everythind..and RCyit all.... :-) :o :-))

how much power she can handle..in pull or push mode..? please wait a while..she is under paint job..will add the super actions later...Friends..have some nice crafts.. :-))
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: tweety777 on February 09, 2012, 03:07:41 PM
I see I was wrong.
After looking more closely to the model I noticed that the propulsion was not really at half length of the vessel, I think that made the difference.
It's clear that the large amount of power helped to indeed make it steer.

Can I give you a challenge?
Could you try to make the same hull shape, but then with the thruster exactly at half the length at the waterline?
I really wander is it will turn then as well.

Greetings Josse
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 10, 2012, 03:15:16 AM
Good morning Friends..and why not Tweety..its on the way..and the above craft is powered by a simple ECM, and powered by a 7.2 volts battery..and the whole video was shot in the mode of about a 2 to 3 % throttle..and if i open throttle once the craft will shooted up in air..so, that power is reserved, to manipulate the crafts around her..now added the pusher platform, and pulling hook..and also made two, tow barges that can carry two bricks each..and will add to my chubby to reveal her's power..and she has only one option...just obey the command from my TX..because she is not my wife.. ;)

and will full fill the dream, that a craft with a propultion at amidship, and  can turn the craft in a circular motion..inspirations..and now challenges continued.. :-)) have a nice day to you all..once again..see how easy to make all crafts..so..make it..many... %%
Title: Re: Make this simple thrust vectoring mechanism for our boats and tugs..
Post by: rathikrishna on February 10, 2012, 06:17:33 PM
Mike..its for you..once again..a million thanks for the challenge..next one..an amphibian capable of VTOL..
see the amphibian here..http://www.modelboatmayhem.co.uk/forum/index.php?topic=35379.0