Jezza15

Robrow

Here you go: http://amtjets.com/download.php#smoke I have seen these systems work well.

From my early homebuilt days till quite recently I used a speed controller/fuel pump combo which also worked well.

Rob.

Jezza15

Excellent - Many Thanks

What would be the best fuel to use in the smoke system tanks? - Is diesel ok?

Henry Chua

My Feedback: (5)

Paraffin. Less messy tha diesel.

Regards
Henry

Robrow

Best fluid to use is purpose made smoke fluid or 'white' oil designed for the food industry. Diesel works ok but tends to be messy and the smoke is more grey in colour.

Rob.

jonkoppisch

My Feedback: (162)

I didn't know that the propane line acted like a pressure port. Does this only work with AMT turbines?

Gerald Rutten

No, works for all other turbines as well.

Best regards,
Gerald

jonkoppisch

My Feedback: (162)

That's a great trick! Save weight and simple!!!

i3dm

My Feedback: (51)

the pressure trick does work well, and i like the simplicity of having a servo drive a Festo ball valve.

The only thing im wondering about is which servo is used in such a case, as the Festo ball valves are pretty hard to move by hand ? would probably require a pretty good torque standard size servo ?

jonkoppisch

My Feedback: (162)

Does it have to be a festo? How much air pressure is there? Will a retract/brake etc valve work instead? I'm sure that a solenoid would be fine as well but a little pricey for the app..

KC36330

the pressure is quiet high and the only smoke tanks i found that would work with it were recycled PowerMax cans. a note of caution, the air exiting the propane side is VERY hot and if you use an excessive flow of fluid or you leave the valve open when the fluid is exhausted, you run a very good chance of melting the propane lines and festo fitting as well as the lines to your smoke system.

i3dm

My Feedback: (51)

A solenoid is perfect, but pricey. just like you said.

jonkoppisch

My Feedback: (162)

Sounds almost like an earlier model Tams smoke system.. I used to run one on my roo!

jonkoppisch

My Feedback: (162)

I wonder how they're regulating the air pressure in the diagrams? It looks like they're using plastic tanks???

i3dm

My Feedback: (51)

they dont regulate it. most plastic tanks are pretty good pressure wise. see all the folks running nitro YS engines with pressured tanks ?

KC36330

A YS has about 4 psi. A JetCat many times that.


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i3dm

My Feedback: (51)

the YS motors i saw (never measured) all balooned up the tanks like mad ! so i really doubt its 4 PSI.

KC36330

My point exactly. At 4 psi a YS swells the heck out of a plastic tank and can burst a fiberglass one, the pressure off a turbines bypass air will explode them.



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Gerald Rutten

A powerful turbine can deliver about 2,2Bar overpressure ( 32 PSI ) which is quiet substantial, still a lot less than used on pneumatic retraction systems. However, no fiberglass tank is designed to hold any pressure so they cannot be used for this purpose. When using pressurized smoke systems only use plastic tanks, and test them first by pumping them to 35psi to make sure you don't have to clean you model's internals..... Also installing a check valve between turbine pressure port and smoke tank is a wise idea so no fluid may accidently be pumped into the turbine when flying inverted, closing smoke valve and downspooling the turbine so it has less pressure than stored in the smoke tank.

Best regards,
Gerald

ianober

My Feedback: (12)

Just get a Sullivan Skywriter and be done. Its the easiest, safest and cheapest solution out there.

Gerald Rutten

Well........that's just where this thread startet, wasn't it? A valve for just a few bucks against this sullivan pump for allmost $100,- isn't very cheap, is it?
But I agree, when you want a ready installation and aren't very handy I would go for the pump system as well. As a hobby purist I like to try everything thats sounds simple and easy to me but not everybody likes to (or should....) experiment.

Best regards,
Gerald

MLJETS

Hi Gerald, I do agree with you. This way to make smoke is the cheapest and works fine without adding much weight in the model. I did it in the past in 2 different models.

RemoteJets

My first test with my gasstart Jetcat 120 and pressurized with the gas inlet:
[youtube]http://www.youtube.com/watch?v=PpIPjrtx_mQ[/youtube]

Have to fine tune the set up more and then build it in the airframe somewere