Quick question as I have heard both ways, when injecting smoke fluid, is it better to do it at the tail end of the pipe, or can you inject at tail of turbine as it enters the pipe? I ask as I here some say that it stresses the pipe. Any suggestions would be appreciated.

This may help.

http://www.rcuniverse.com/forum/m_11...m.htm#11524940

I have a Carf EURO and inject smoke at rear of pipe. Works well. Smoke appears about 500mm from end of exhaust. Using Sullivan smoke pump and diesel as fluid. 4mm brass tube on inside of pipe to 4mm stainless injector into exhaust.

Rear of the pipe! It avoids the thermal shock and is how the full scale birds do it. Bifurcated pipes especially. I run one smoke tube at the end of each pipe outlet on my bifurcated F-4 and it works very well. I used to have it mounted at the turbine and there is no noticible difference.

Could you please advise how did you connect the 4mm brass tube to the stainless steel injector? (presume that they are connected inside the pipe) correct?

Thanks in advance,

Regards,

one tube inside the other (brass the outer, stainless the inner) about 4 inches of it and lots of solder to sea lthe gap. you wont solder the stainless but it seals the gap, no leaks so far but dont try and turn the stainless tube seal breaks.

I use both methods with no visual difference in the amount of smoke i get . On the tail end method i run the brass tubes through the double wall of the pipe and i do not use the ready made nozzles but instead i put the edge of a hobby knife at the end of the brass tube and hammered it and the gap is just good enough to get a very good smoke quantity out.

I simply push -4 Festo line over the smoke injector tube.

My F-4 with fluid at the back of the pipe.

Interested in the end of the pipe approach. How do you pipeline it down there to the end of the exhaus nozzle, 4mm festo tubing or brass tubing? or other?
It does seem the end of the pipe approach is safer.

The Phantom II is very roomy so I just ran my 4mm line down each side of the fuse then onto the injector tube on each side. I attached each injector tube to the fuse. I ran the tube thru the holes in the aft pipe support ring and then bent the tobe 90 degrees into the exhaust stream.

On the streight pipe setups I would lengthen the injector with more hard tube and pass it between the walls of the pipe to superheated the fluid.