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[KBIO]

Hello!
Tonight I present you my last launch : FANNY. It is not finished yet and I have to work out the details. But when I see what Bernhard achieves, I just try to copy as hard as I can. Thanks Bernhard, but I never get your talent!
The hull is from Orion moulding and I took off two clinkers also. It looks better on the water.
The engine is 25cc Saito and the boiler is an old one I had for years on my shelves. 27cm long x 12 cm diam and an old burner burning like a Kuweiti flare during invasion period.
.



The following photo shows the firts way I installed my burner (gas phase) ,


But it was not performing well enough and I decided to try liquid phase. This is my final installation . The first one brought the gas too hot to the regulator with danger of melting membrane.. I reach 2 bars in 12 min and I can run full blast for 1.5 min before the pressure drops. Even blowing the whisle. I am glad of the result. Only problem, I have only 15 min autonomy running fairly. I need a bigger gas tank or increase my beers suitcase as I shall come back on shore more often!



I should be able to propose a video some time , with the launch running like a "gazelle"!

Hope you like it!
Regards!

[Bernhard]

Hi.........What a great big launch you have build. ..look so real..special on photo 3...hope you willl get 25-30 minuts running with a bigger gas tank...

Regards Bernhard

[livesteam]

C'est fantastique, tu as beaucoup de talent 

[derekwarner]

  excellent build KBIO  ...I am very interested in the gas refilling valve in your gas tank 

It appears as shown in many French model vessel gas tanks as suitable for conventional "push" type connection as compared to the EN type screwed connection

Any assistance with the source of the "push" type connection valve would be greatly appreciated.......

I post an image of the two types of gas cannister below......Derek

[mogogear]

excellent build KBIO  ...I am very interested in the gas refilling valve in your gas tank 

It appears as shown in many French model vessel gas tanks as suitable for conventional "push" type connection as compared to the EN type screwed connection

Any assistance with the source of the "push" type connection valve would be greatly appreciated.......

I post an image of the two types of gas cannister below......Derek

Derek

Here is one I found to use the "bayonet " type gas cans--http://modelsteam.myfreeforum.org/about39319.html

[kno3]

Hello, nice boat!
Is that the largest Saito engine?

I'd also like to know more about liquid phase gas burners. What's the advantage of using them and how exactly do you convert the liquid to gas for the burner?

[kiwimodeller]

kno3 I have come across a plumbers heating torch of the Kovea brand which the maker reccomends be used with the cannister upside down so that liquid flows to the burner rather than gas. It has a small diameter copper tube which runs from the connection point to the torch up to the front of the burner, loops and returns to the back of the gas jet. The idea is that liquid flows to the torch, is heated in the copper pipe and then burnt as gas. They do reccomend starting it in the usual way with the the cannister upright and warming it up for a minute or two before turning the cannister upside down. The advantages are supposed to be "a hotter and more consistant flame" according to the maker. Sorry for the long winded explanation, I will try and get a photo of it. Cheers, Ian.

[kno3]

Thanks, a photo would help!

[KBIO]

Hello!
Concerning the "quick coupling" I use for gaz transfer, it comes from Ludger (Germany) : http://www.dampfmodellbau-keifler.de/pic/14-2030.jpg
The only problem is that Ludger changes the seal to instal : Viton.
 Nitrile is recommended for low temp . Although 30/70% BuPro mixture must be +/- Minus 20°C I never had no problem.
I like this system because I can transfer liquid in my tank whatever the position of the tank inside the boat without removing it and pushing or freezing my fingers.
Thru the silicone tube, I can see the liquid flowing down the tank. I just return the main tank to have liquid right away. Bleed oof valve wide open on the tank inside the boat for quick fill up.
When my tank is full (80%), I shut in maoin tank reserve, i disconnect the coupling and I shut oof the gas tank inside the boat.


As the gas in cannister is very expensive in France (+/- 7.5€) , I use a bigger bottle wich contains butane only and I save a lot of money!

Now, concerning the liquid phase This is my first trial. I decided to go for it to help having pressure in my gas tank during cold period.
Remember that butane boiling point is +/- 0°C and Propane - 45°C. So if you have a 30/70% BuPro mixture. The Propane burns first and in cold weather < 60% butane remains inside the tank.
This has been very well explained in this forum.
So , as (roughly) a drop of liquid is equivalent @ 270drops of gas at standards conditions. If you allow a drop of this liquid to go the burner , you maintain good pressure inside the tank and , when this drop is warmed up it expands such a way that it blow to the torch.
I am sure that English speaking people will explain this properly.
Remember that you need a ckeck valve at the oulet of the tank and then a radiator to cool down the gas before it enters into regulator, shut of valve or anything with rubber inside.
For those who speak French, I explain this in here: http://modelismenavalradioc.nouvellestar6.com/t1920-vapeur-par-grand-froid-et-solution
I hope , you understandme good enough.
Regards.

[derekwarner]

Thanks KBIO...I have a similar problem......here in OZ....

1. a 420 gm 30/70% BuPro mixture disposible gas tank with the EN series screw formed thread is approx $6.50 AUD
2. a 420 gm 30/70% BuPro mixture disposible gas tank with the bayonet connection is approx $1.20 AUD

My issue with the Forrest Classic gas tank was the center distance between the filling nozzle & the discharge valve disk handle......but think I have resolved it now with a simple extension piece  

It appears that I can get approx 180g of fluid into the tank prior to natural exhausting......& the left over gas can be used for soldering flame........ Derek

[america12mj]

Yves goodnight,
  happy to find you here, but I'm not as English as you.
if interested in our English friends I'll put the link to our accessories filling fast
a bientot

pascal

http://www.aerographes-services.com/Cata.htm

http://www.aerographes-services.com/Cata.htm

[KBIO]

Hello!

the left over gas can be used for soldering flame.

I do the same and I even start the warm up of the boiler with them.
Concerning the use of aerograh quick couplings, I would not recommend it, as the seals in use are for compressed air and not for cold gas liquid. I must admit, that I use some of them with no problem so far , but ....................... carefull!
Still, the idea to use them is good to me!
Regards!

[kiwimodeller]

As requested by Kno pictures attached of the Kovea Canon torch. The first photo shows both the standard torch and the one which the maker says can be used in any position and will run on the liquid fuel. The second photo shows the latter dismantled. Dont worry about the control etc, I have cut off the pipe between the control and the torch so I can replace it with a flexible pipe. I have tested the torch and it can be started with liquid running to it but it does warm up better if it starts on gas and then switches to liquid. Hope this helps. Cheers, Ian.

[kiwimodeller]

Dont know what happened to the first photo on the last post but here we go again!

[Roadrunner]

A very nice model well done, im sure Bernard will say the same, they also say copying is the best form of flattery. 

[kno3]

Thanks for the photos.

[KBIO]

Good evening!
Today I have decided to change the supply of my burner for liquid gas only! I disconnected the gas line and kept the liquid one only.
Problem: the gas was too cold prior to enter to the shut off valve = I did one more turn around the burner!
Then it was too hot before entering the same valve = I made my heat exchanger longer and slightly bigger ==> perfect.
The hot gas comes with high pressure but it is cooled down to ambiant temp entering the control instruments.
To allow some positive pressure to stay longer inside the tank and to avoid a wild flare, I used a pressure reducer. The flare is now "civilized" and whatever the pressure inside the tank, I wide open the main valve and it burns smooth and long!
La vie est belle!
Cheers!