Model Boat Mayhem - Forum

Please login or register.

Login with username, password and session length.
Pages: [1]   Go Down

Author Topic: Unintentionally went swimming! Fuel tank  (Read 2268 times)

tjones27

  • Guest
Unintentionally went swimming! Fuel tank
« on: November 28, 2010, 03:21:05 PM »

Hi,
well I'm not in a good mood, as at minus one air temperature i had to go swimming to retrieve my I/C boat. i had to test run it out in the Poole in the bay. after a bit of thinking as to why the engine may have cut out i seem to have sussed it. although i had at least an inch of fuel in my fuel tank when i give it some beans and the nose lifts out of the water the fuel obviously flows to the back of the tank, Ive installed a nitro car fuel tank which I'm now not happy with as i nearly caught hypothermia because of it. so what fuels tank should i use? i considered turning the fuel tank the other way around, but if i slow down then i will get the same problem. any ideas please?  Tj
Logged

dodgy geezer

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,920
  • Location: London
Re: Unintentionally went swimming! Fuel tank
« Reply #1 on: November 28, 2010, 03:30:52 PM »

Either use a tank with the fuel feed through a sump, or use a clunk tank like the aerobatic flyers use.
Logged

thegrimreaper

  • Guest
Re: Unintentionally went swimming! Fuel tank
« Reply #2 on: November 28, 2010, 03:47:31 PM »

agree with dodgy geezer clunk tank or weight the end of the fuel pick-up tube with a small lump of brass
Logged

50mm

  • Guest
Re: Unintentionally went swimming! Fuel tank
« Reply #3 on: November 28, 2010, 03:52:29 PM »

build your own like we used to during the 60's and 70's, Get a sheet of brass and roll a tank add some end plates and silver solder together, on the base at one side add a sump which is the fuel outlet, on the top add a screw on cap.

Depending on where you fit the tank and which way round you face it will depend on the type of stand you need to make, what you should do is have a stand that forces the fuel to run towards the sump allowing fuel to be continually in the sump.

 The other method would be to pressurise the fuel tank using the tune pipe, fit  a nipple to the tune pipe and run a rubber tube to the fuel tank lid where it shold connect to another nipple, when the engine runs the exhaust pressure forces a bit of it in the tank pressurisng the tank and forcing fuel up the line to the carb  :-))
Logged

dodgy geezer

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,920
  • Location: London
Re: Unintentionally went swimming! Fuel tank
« Reply #4 on: November 28, 2010, 04:37:51 PM »

The other method would be to pressurise the fuel tank using the tune pipe, fit  a nipple to the tune pipe and run a rubber tube to the fuel tank lid where it shold connect to another nipple, when the engine runs the exhaust pressure forces a bit of it in the tank pressurisng the tank and forcing fuel up the line to the carb  :-))

not sure that pressurising would help if the problem is fuel sloshing around in the tank..but I agree that making your own fuel tank will enable you to baffle it as much as you want...

This is what I used in the 1960s on my Sea Commander - produced very reliable runs in quite rough water...



Logged

tjones27

  • Guest
Re: Unintentionally went swimming! Fuel tank
« Reply #5 on: November 28, 2010, 04:52:14 PM »

Thanks for that image geezer. that will definately help. i shall start right away. many thanks
Logged

50mm

  • Guest
Re: Unintentionally went swimming! Fuel tank
« Reply #6 on: November 28, 2010, 05:06:38 PM »

A 'sectional tank' would stop the sloshing about the tank will have 2 to 4 vertical walls that are 3/4 the hight of the tank fitting internally, at the base section of the walls drill a section of holes, this will reduce the sloshing effect dramatically as the fuel is contained in a few smaller sections , the holes are to allow the fuel in each section to progress towards the outlet.

obviously this method works on a home built tank but with great effect.

diagram below shows the principle
Logged

Netleyned

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 8,986
  • Location: Meridian Line, Mouth of the Humber
    • cleethorpes mba
Logged
Smooth seas never made skilful sailors
Up Spirits  Stand fast the Holy Ghost.
http://www.cleethorpesmba.co.uk/

50mm

  • Guest
Re: Unintentionally went swimming! Fuel tank
« Reply #8 on: November 28, 2010, 05:30:09 PM »

method for retrival with out going for a cold swim, as we do here.

1 no ones stupid enough to go swimming when IC boats are concerned so we have a dedicated rib to play fetch.... but in your case buy a cheapo blow up raft.

2 fit a hook on the boat like a key hook or something similar will do , get a tennis ball and pop a hole in it top and bottom, get some line 4mm should be suitable and as long as possible. pop the line through the tennis ball and tie it off as a loop around the ball, you can do one of two things if you got a good pitching arm throw the ball over the boat and try to hook the line on the boats hook and pull back to shore, of if the boats way out and you throw like a girl get one of those dog tennis ball throw things like an arm extension and lob the ball, those things really can knock a ball out a fair way! same thing try to hook the boat and pull back in.

3 have another rc boat push you back to shore

4 get a new found land dog (they love swimming even in the cold) teach him to play fetch with the boat!

5 if you exhausted all them methods the wetsuits your last hope and your going swimming! 
Logged

tjones27

  • Guest
Re: Unintentionally went swimming! Fuel tank
« Reply #9 on: November 28, 2010, 05:52:26 PM »

HAHA, {-) love the idea of a wetsuit. well i did pop into the asda that was nearby tosee if they had anything inflatable. but no only some rubbly buckets that would have jsut sunk. i would have taken my paula with me as a retrieve, but she is in the middle of a mod. but the tennis ball idea is brilliant. that may indeed be the way forward. a hook on the bow and stern so that way i should have a chance catching it. i was also looking for a fishing rod as that would help with the distance, but im not too sure about the accuracy, but would be esy to reel in :)
Logged

50mm

  • Guest
Re: Unintentionally went swimming! Fuel tank
« Reply #10 on: November 28, 2010, 06:25:03 PM »

fishing rod is a reasonable idea but the issues with that are the line will require some weight to cast out so your risking damage to the boat should you accidently hit it where as a tennis ball will bounce off, the other issue is if you cast over the boat and the weight sinks as it will, should the weight snag on the bed you not only have a stuck boat but a stuck line to pull in, and worst case if it dose catch the boat and then snags up you have to pull the line risking serious damage to the boat should the line ping back or worse sink the boat if its not quite sealed for a capsize, where as the tennis ball floats and it soft.

the advantage over the ball method to a rod is that you have to carry extra in the car such as the rod, and a reel set it all up and it all takes up room and is not a quick retrieval, where as the tennis ball and rope method is a small box bundled in the boot for quick retrieval (just make sure you don't bird nest the line!) , remember next time it may not be a cut out it could be a fire of sinking! 10 mins messing about with a rod and your boats sunk and lost, at least with the ball you have a few mins to attempt to get it quick.
Logged

tjones27

  • Guest
Re: Unintentionally went swimming! Fuel tank
« Reply #11 on: November 28, 2010, 06:48:23 PM »

true true. sorry i didnt make it clear, i was thinking of maybe putting the tennis ball on the end of the rod. that way you have the best of both worlds. but maybe having two depending on the distance and time you have. but anything is better than wading out and going for a swim in the winter. i could have bitten the bullet and watched it float away but im not that sort of person. so rope and tennis ball is on the shopping list for tomorrow and some materials for a new tank. next weekend looks like it will be going for anoher run. but no swimming!! :-))
Logged

John Mk2

  • Guest
Re: Unintentionally went swimming! Fuel tank
« Reply #12 on: November 28, 2010, 07:28:23 PM »

Get one of these  %) It was mine :-)

http://www.youtube.com/watch?v=PRKD7ZPvt5Y
Logged

Tombsy

  • Guest
Re: Unintentionally went swimming! Fuel tank
« Reply #13 on: November 28, 2010, 07:57:39 PM »

My tennis ball does most of the retrieve work unless the wind is blowing the wrong way, thread your tennis ball with 10ft. of cord and attach it to some fishing line on a push button spinning reel attached to a short handle.
Twirl the ball around like an old fashioned sling shot you can get deadly accurate and quite far.
I mount a metal ball end on the front of all my boats to snag the line.
Please don't swim after a toy boat it's not worth it, there have been more fatalities this year.

When the ball fails here's my rescue rig
http://www.youtube.com/watch?v=NrIcC8eO3Wg
Logged

tjones27

  • Guest
Re: Unintentionally went swimming! Fuel tank
« Reply #14 on: November 28, 2010, 08:49:33 PM »

yes. well looking back i do know that swimming is silly. although i do have to admit that there wasnt really that much swimming involved. the tide was out, but it was deep enough. up to my chin. i do like the rigs. im thinking of attaching a really strong magnet to the crane of my paula and a metal plate on the front and or back of my racer to then go out there and to it back like that. but ball and string is the best option for now. im defiantely going to have a bit of practice first though :)
Logged

dreadnought72

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 1,871
  • Wood butcher with ten thumbs
  • Location: Airdrie, Scotland
Re: Unintentionally went swimming! Fuel tank
« Reply #15 on: November 29, 2010, 12:28:43 PM »

To throw anything accurately and a long way, I can only suggest the staff sling.

(I made one in my Medieval re-enactment days, and it was a real eye-opener to me - those Ancients weren't as daft as we might think.)

Andy

Logged
Enjoying every minute sailing W9465 Mertensia
Pages: [1]   Go Up