To much smoke

[Phil Woollard]

Right you guys stand easy. That's spooky these two posts of mine are some how linked together!

[Phil Woollard]

Ok you guys stand down and stand easy, we are digressing a little....my first encounter with making smoke was in the early 1980's producing smoke to screen the fleet from missile attack, using rotary wing aircraft down in the south Atlantic...I shall say no more as now I am digressing lol.

[Phil Woollard]

Well this is the prototype blower and first impressions are good, it simply runs a big fan flat out all the time which is sealed when the butterfly valve is closed (all the while smoke is being produced and most of it is held in the chamber) The servo is running off the left motor rx lead and opens the valve proportionately in forward or reverse, the smoke for tickover is just enough due to leakage of the valve but when you give it the left stick a huge amount of smoke and air pressure is instantly released. The snail fan is 120mm and coupled with the butterfly valve gives that blast and flow that I have been looking for.You dont have to wait for the fan to catch up.
The smoker unit is standard and seems to keep up with the large volume of air produced by such a huge fan and quickly reduces the smoke stream to a more believable rate with tons of pressure, all I have to do now is fine tune and practice a few smokey gear changes.
I will shoot some video and post soon.

[Phil Woollard]

As I said this new concept smoker of mine looks very promising indeed, I want to experiment with Adrian's unit connected also for that extra control.
I have been experimenting with pulsing the exhaust stream , it works if you wobble the tx stick back and forth ,the motors are disconnected I hasten to add, can anyone think of a way to pulse the stream without wearing out the servo and linkage? I'm not that worried about wearing the servo out so much as they are rel cheap
Cheers smokey phil

[Phil Woollard]

Smoke and plenty of it When I get time I shall shoot some more video of the new smoker and edit the lot together for discussion

[Sam Hough]

Has anybody tried using a piston based pump to spit out the smoke? I've got the original small fan and it is a bit feeble. The real thing "pumps" using pistons so might look good?

Cheers

Sam

[Phil Woollard]

Hi Sam, our liam is working on a pulsing smoker right now. I am thinking of offering my unit for sale, I will post a photo of the new valve which tidies up the design.
The piston approach is cool! cheers Phil.

[Mark Heaps]

In my experience on real tanks, Challenger 1 & 2, and other armoured vehicles they only really smoked during starting and until warmed up. Once warmed up the exhaust gases were clear. A bit of smoke was normal and to be expected if the engines were shock loaded ie a sudden acceleration.
If they were smoking whilst warm and idling, then the colour of the smoke indicated the type of fault we had to then deal with.
White - Coolant was being burnt
Blue - Oil was being burnt
Black - Carbon was being burnt

[Phil Woollard]

Hi Mark, that's very interesting with the colour fault diagnosis, we can only really make the white smoke and thin it down somewhat with our smokers. The old Maybach v12 suffered from terrible overloading issues and frequently overheated, the latter causing the older style head gaskets to fail and so let oil and water into the combustion chamber.

I am using liquid parrafin in mine which gives a lot of smoke, probably "to much smoke" but this with copious amount of high pressure (well as higher pressure as I can get from the 150/200mm fans) smooths out to form that theatrical smoke column, going back to Liam's new smoker.......it looking very promising with a pulse effect also, the pulse obviously to represent the "suck squeeze bang blow" , although as I pointed out his Tiger1 exhaust plates kind of arrest the pulse. So I am thinking that it may work best with a no flow interruption, like the Panther straight up pipes or remove the T1 plates altogether.
You probably guessed that I am quite passionate about this subject and find it fascinating, maybe because it is so theatrical and so adds to the illusion of 1/6th models looking even more real! ...Phil.

[John Heath]

Curious as to why no one here seems to use the stuff used in stage smoke machines. Called Smoke Fluid or Fog Fluid it's designed for the job of producing smoke effects using a heated element and it's not very expensive. There are a range of viscosities available that give differing amounts of smoke and it doesn't leave any residue behind and is non-toxic.

Use it in my 1/16 tanks were it does a good job. Can be picked up on eBay cheaper.

https://www.stagedepot.co.uk/scenic-eff ... luid/smoke

John

[Phil Woollard]

Some evidence please John, maybe some video as I am not familiar with the product

[John Heath]

Can't find the video but here's an image that gives some idea. Basically the same stuff that Tamiya sells as smoke fluid,just a LOT cheaper.

John

[Sam Hough]

Great. Lots of info.

Mark: I was hoping to detect "shocks" to the engine and drive smoke and extra sound samples. I thought that going from high torque to low would produce the most smoke? Throttle still full open engine unloaded?

Cheers

Sam

[Mark Heaps]

If an engine and its exhaust system is working at its optimum efficiency then the amount of smoke is minimal and hardly noticable. The airflow out of the exhaust disperses what there is without it being immediately obvious to an on-looker.
Obvious visible smoke is an indication that something is wrong at that moment in time, either excess moisture, oil or fuel.
Barring any fault with the engine, I would expect smoke on start-up ( due to unburnt fuel along with moisture in the air ) and in high load situations ( low engine revs, throttle fully open, terrain or gradient restricting the vehicle acceleration ) from unburnt fuel.
Taking the load off the engine would allow it to speed up thereby dragging in more air and reducing the fuel/air ratio.

[Sam Hough]

Thanks. Lot easier to detect high loads than spikes etc.

btw I was amazed how much current gets drawn doing slow gentle turns on grass.