RC India

I would like to know the fuel composition for diesel engien
i have a sharma model diesel engine.

Amir

Fuel for model airplane 'Diesel' engines (compression ignition 2 stroke engines) is as follows:

1 part Anaesthetic Ether
1 part Kerosene
1 part castor oil

The problem with these engines are:
a. starting is more difficult than glow (very temperamental)
b. control of rpm.... not possible by way of control by a servo
c. the compression ratio reduces as the engine wears reducing the power output


The second point above makes it very inappropriate for an rc plane

Saju

i have to use it on glider. so no need of throttle control.

I was waiting to see who answers this, since this is something I never knew about  :)

So you just let the glider run out of fuel and land ?  How would you stop the the engine ? 

I did see some diesels engines with carbs on the Sharma Model website, so I guess it may be possible to do throttle control with a servo ?

yes diesel engines with throttle control are also available with sharmamodel but this particular engine is without throttle control.
first we take off and when fuel gets over it glides, no need to turn off the engine. it automaticaly does..

You can actually decide how long you want the engine to run, before the fuel finishes.
You cold use a very long fuel tube, say around 50cm connected to the fuel tank. once you are ready to launce the plane, disconnect the tank and let the plane/ glider go.
That way, you can time the engine run more accurately than by using (hard to get) metal/ diesel compatible fuel tanks. Less wieght on your glider as well.

The older free flight diesels ran the same way. they had a tiny fuel tank built under the venturi.
Avijit

sir,where to get ether for diesel engines in chennai? or is there any one selling ready made diesel fuels in chennai?

mayura chemicals.

Well.. I will request you all to make your own fuel as it is cheaper and very very simple... the ingredients required are : -
Solvent Either 33% by volume
Kerosine 33% by volume
Castor Oil 33% by volume.
Just buy the commercial verity available and not go for analytical one as there is no need of going for a very pure either which is just a waste of money.  As your engine is run in well enough you may change the ratio to:-
Solvent either 30% by volume
Kerosine 40% by volume
Castor 30 % by volume.
I have used up to 50 % of kerosine at times...
No need to add any nitro or such things... if you feel you may add 1% of any of the diesel fuel additives sold at petrol pumps as they help in better burn and cleaner engine.

Yes I have used diesels with variable venturi for RC models earlier.  They may tend to be a bit of a trouble but if you know you engine well they handle pretty good. 

@Nitesh, are you sure that Mayura chemicals sell Diesel fuel for RC diesel engine?

they do sell nitro so I thought they sell diesel too.

Please do not recommend if you have no idea. i dealt with them before and they sell only nitro fuel not diesel fuel.
(As far as i know and to the best of my knowledge, i do not see anyone selling mixed diesel fuel except lotus hobby who just sells Ether and Lubricant. it seems like the Diesel guys have no other option but to mix it on their own.)
Assuming is dangerous for both the parties.

The reason for not having pre-mixed diesel fuel is solvent ether's very high volatilty. When you mix your own, ensure your container is sealed airtight, and mix only as much as you can use in a few days

Well I suggest everyone not to buy fuel from all these vendors.... One can mix fuel at home whenever you want.  Always use freshly mixed fuel and your experience will be good. 
OK.... go to the chemical dealers shop in your town (remember the dealer who stocks all the chemicals for the Chemistry and Biology labs of school and colleges in your town....).  He is thw guy who will give you all these items in 500 ml or 1 ltr packings or bigger ones.  I suggest you buy 500 ml packs ro the 1 ltr ones and not the bigger ones.  Mix the fuel just before you leave for flying and mix just as much you are planned to be using that day.

Diesel fuel has solvent either in it and this is very volatile.  So best keep the bottle tightly caped and use it fast or else the either will evaporate by itself

sir,i have got another option ahead of apple box glider that is pg 15 kit from lotus hobby.this model kit costs rs 1800..which is much more cheaper than the apple box.i am really confused :headscratch:

I do not know of PG15.... by the look for the picture of the model it does appeal to me.

Lab grade solvent ether (diethyl ether, puity 99% ) is available in chennai.
500ml bottle costs  :Rs:540.
Address:
mahaveer chemicals,
old no. 4, new no. 120, nyniappa (n) street, chennai 600003.
Mahaveerchemicals1976@gmail.com.