Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length.

[Geoff]

I think its easier than that, Given that any turret has two guns and would typically fire one at a time you can put a very bright LED in one barrel and use the other for the smoke ejection. Again what I plan to do with Iron Duke.


From any distance the brain will see a flash, a cloud of smoke and hear a bang and add it all up to gunfire.


Fibre optics are a good idea if you can't get the LED at the end of the barrel, or use acrylic barrels as the light transfer medium.


Geoff

[tonyH]

Some months ago there was a thread where a bloke in Holland used the works from a disposable camera to produce a very clean flash and a sharp crack. I saved the photos (See below) but can't seem to find the thread.

[tonyH]

Found the thread but further back than I thought. 1st post on Warships R&D on 1st Dec 2013. Photos/plans missing as are the YTube films but it may be worth a search further if the text whets your interest.

Tony

[ballastanksian]

If the LED were mounted in a piece that also acted as a diffuser in the muzzle then you would kill two birds with one stone Bob. The diffuser/mount could also be used to route the wires away from the vapour and possible moisture issues with shorting.

Re the fluid used in E Cigarettes, you can get non nicotine solutions for those who are on the last leg of their giving up smoking and just have the residual 'Habitual act of smoking' to give up after the need for nicotine has abated sufficiently.

I reckon the E-Vaping mechanism is the safest and most effective creator of mist for its size and weight. It just needs sufficient draw and a method of projection to make best use of the vapour before it condenses toomuch to be of use.

[red181]

take a look at mrrcsound website. I have the v4.1 soundcard, fitted in a model P51 Mustang, its utterly amazing, with engine start up, shut down, throttle sensitive, then, hook ups on the board for gunfire, linked to flashing leds, and so on.

What you will want to look at are the speaker replacements, called TT25 transducers. They attach to the body of the plane, or boat hull, and this becomes the speaker, so no bulky magnets etc. Do a bit of googling, youtube etc. He does soundcards for boats, tanks etc, but primarily its for planes, with a  load of engine choices. Not cheap, but you get what you pay for. Extensive thread on rcgroups, under vendors. I have a couple of sound units in boats, and would definitely use the TT25's in place of speakers if I did it all again

 http://test.mrrcsound.com/

[essex2visuvesi]

take a look at mrrcsound website. I have the v4.1 soundcard, fitted in a model P51 Mustang, its utterly amazing, with engine start up, shut down, throttle sensitive, then, hook ups on the board for gunfire, linked to flashing leds, and so on.

What you will want to look at are the speaker replacements, called TT25 transducers. They attach to the body of the plane, or boat hull, and this becomes the speaker, so no bulky magnets etc. Do a bit of googling, youtube etc. He does soundcards for boats, tanks etc, but primarily its for planes, with a  load of engine choices. Not cheap, but you get what you pay for. Extensive thread on rcgroups, under vendors. I have a couple of sound units in boats, and would definitely use the TT25's in place of speakers if I did it all again

 http://test.mrrcsound.com/

Wonder if the TT25 would work with the Action P100?

[essex2visuvesi]

Wonder if the TT25 would work with the Action P100?

Sadly not


The P101 Amplifier requires an 8ohm speaker and these are 4

[C-3PO]

Transducer/Exciter - http://y2u.be/j2SqHMZ2Dao

MrrcSound transducer image looks very similar to this £3.59  https://proto-pic.co.uk/2w-4-ohm-electrodynamic-exciter/  - only £2.10 from Kitronic

Think the first 2 items are 8 ohm https://proto-pic.co.uk/search.php?search_query=surface+transducer

This is an alternative https://www.youtube.com/watch?v=4qxakHiJ7CM

https://www.kitronik.co.uk/catalogsearch/result/?q=exciter

I wonder if this has any detrimental effect on glued joints after a period of time?

C-3PO

[Bob K]

Wow.  I thought my initial query would bring up some existing / proven methods for achieving this without pyrotechnics such as gunpowder.  Instead it has become a Think Tank for many exciting ideas and possibilities.  Thank you everybody.  So much to consider.

With two close fitting barrel tubes I am sure a 12.5mm recoil could be arranged on the outer which briefly exposes the diffuser mounted LED 'bulb' in the inner.  How much that would restrict the smoke flow is subject to trial of course, but could be significant without high pressure.

[C-3PO]

Hi Bob,

Indeed a good collection of inspiration - sure it stirs up some long lost boyhood stuff to do with smoke, flashes and bangs!

Another link for your development melting pot - This company "TCS Micropumps" seem to make "real" pumps compared to eBay items. Not cheap but proper engineering - I found an Air pump 680ml per minute at 12PSI working at 3-6volts weighing just 30grams 'ish - I think ( based on nothing else but gut feel) that sounds quite a good spec (assuming I have read it correctly which is always a danger)

http://www.micropumps.co.uk/TCSD200range.htm

I have just ordered some of the sound transducer/exciters so I post my experience with them on here at some point

C-3PO

[ballastanksian]

While cheap cigar smoke would provide a drier and therefore more stable smoke, a nicotine free vapour fluid would be useable indoors should you have the urge to display it on the stand My concern with fog oil is wether it would leave an oily residue? Mind you, cheap cigar smoke will leave nicotine stains, so vapour fluid seems to tick the boxes.

[Martin (Admin)]

DIY nicotine free vapour fluid

 https://youtu.be/MTI0CuPvOB0

 https://youtu.be/4Xe4mXnvej4

[craggle]

That's an interesting thought, Wonder if I could use one of those e-cigarette things as an exhaust smoke unit in my lifeboat? Would be quite easy to rig up a small fan to blow through it occasionally to produce a puff. Wonder how long they would last?

Craig.

[Geoff]

As an observation, whilst the e-cigarette fluid produces a significant cloud of smoke which is ideal for what we are looking for we should consider that in practice this is mixed with the air in your lungs (several litres worth I think) before its exhaled in the smoke cloud.


This was the basis, albeit using fog fluid, for my experiments with Iron Duke - the need for a mixing tank to mix the vapour/smoke with air to create the volume we are looking for and then pump it out the barrel.


It may be that this process is unnecessary if we assume the "raw smoke" is mixed sufficiently with air after/as it leaves the barrel.


Accepting that maybe a fish tank air pump can force it out the barrel which would add to the volume. I guess only practical experimentation would work.


Anybody out there with a e-cigarette they can try putting it into a narrow tube and blow very gently from the other end to see how the "smoke" behaves?


I have used fog fluid for many years and don't really find any residue on the model after usage - be warned though even though is "fog" it will set of fire alarms as a certain community centre will testify many years ago!!


I'm in the process of building some sample guns to see how they respond to production of fog in a confined space rather than a large space and will report back.


The bottom line is we need to produce a significant volume of smoke and eject it from the barrel.


Very interesting topic.


What other air pumps are available?


Cheers


Geoff

[Bob K]

"What pumps are available?"    I am going to try my spare 'Sparkfun' 12V vacuum pump, not sure if this is the right model (looks the same)  https://www.sparkfun.com/products/10398
(You can get them in the UK if you google Sparkfun air pump)

It is quite powerful and shifts a lot of air / min.  I use it to blow out the ballast tanks on my semi submersible HMS Polyphemus. Less than a minute to blow 2 x 1.3L side tanks.

[C-3PO]

Bob,

Sparkfun pump - nice one spec 0-32psi, free flow 12-15 LPM - possibly branded as "Airpo" that should do it!

C-3PO

[Bob K]

C-3PO:   It does have "Airpo" on its ID label, although I got it from Sparkfun.  Shifts a heck of a lot of air at quite reasonable pressure.

[C-3PO]

Guess it's one of these

http://www.alibaba.com/product-detail/Mini-D2028-12v-dc-air-pump_354079276.html

I was going to paste the manufacturers link but it contains the word j e s u s (without the spaces). If you type the jxxxx word on Mayhem and save it automatically changes it to LORD when you save

Give it a go - it's really quite funny

C-3PO

[ballastanksian]

Geoff's point about flow rate is the key I reckon to any successful system.

[Capt Podge]

I was going to paste the manufacturers link but it contains the word j e s u s (without the spaces). If you type the jxxxx word on Mayhem and save it automatically changes it to LORD when you save

Give it a go - it's really quite funny

C-3PO

Same happened to me when I typed in  t o s s e r , as in bunting "idoit" - it auto changed to bunting idiot. (if you try it, you will find the word idiot has been spelled incorrectly as "idoit" )

Regards,

Ray.

[Capt Podge]

....and it's just happened again. Seems the only way to avoid this is to copy C-3PO and put spaces between each letter.

Sorry for jumping in on your thread Bob K.

Back on track now

Regards,

Ray.

[essex2visuvesi]

Transducer/Exciter - http://y2u.be/j2SqHMZ2Dao

MrrcSound transducer image looks very similar to this £3.59  https://proto-pic.co.uk/2w-4-ohm-electrodynamic-exciter/  - only £2.10 from Kitronic

Think the first 2 items are 8 ohm https://proto-pic.co.uk/search.php?search_query=surface+transducer

This is an alternative https://www.youtube.com/watch?v=4qxakHiJ7CM

https://www.kitronik.co.uk/catalogsearch/result/?q=exciter

I wonder if this has any detrimental effect on glued joints after a period of time?

C-3PO

Ordered a couple for testing purposes with the P100 & P101 combination.

[C-3PO]

Ordered a couple for testing purposes with the P100 & P101 combination.

E2V - excellent - we can compare notes - I went for the little 2w one and the big 25w one

Should arrive on the door mat today

C-3PO

[essex2visuvesi]

E2V - excellent - we can compare notes - I went for the little 2w one and the big 25w one

Should arrive on the door mat today

C-3PO

I went for the 2W and the 10 so should be interesting


Mine are going into this:-

[Umi_Ryuzuki]

It may be possible that you can find threaded, refillable Co2 canisters and regulator from a paint ball gun.
This and a bit of creative plumbing and a Clippard MAV-3 valve at a servo could fire a burst of air.

Also a small can of "air duster", for computers could supply air pressure for your gun.

As for a talc or cornstarch gun, it just needs a "powder" reservoir to puff the air into to
agitate the powder. An exit hole and tubing to your gun barrel will give you a nice burst of "smoke".
However, I can't say how much of that talc or powder will settle onto your model.

Here is a quick assembly using an old rx bottle and small 3mm brass tube.
https://www.youtube.com/watch?v=ssX893soYXI


 


.