Wren Turbines USA

My Feedback: (39)

After 6 months of tinkering...

Blows powder thru the front barrel, using a NOS solenoid, high pressure lines and a servo operated cam to trigger the micro-switch. Pressure tank is buried in the center section, and is constructed from two thermos bottle inner liners welded together. Holds 300 psi easily. Filled from a paint ball Co2 bottle.

I am currently using flour as powder, but need some suggestions for a dark colored substance. I've thought about black pepper...but that could lead to a sneezing problem.

turboratt

nice work any video of it in action ?

Wren Turbines USA

My Feedback: (39)

No video yet. The pic shows a small bit being shot out. Actually the tank is empty. And being indoors, I didn't want to shoot a full tank. I'll get it assembled outside hopefully this weekend. Trying to take a still pic with a cheap digital camera is difficult, as it fires three times per throw of the slider switch.

LGM Graphix

My Feedback: (22)

How about grinding up some black chalk pastel's. Would give the added benefit of realistic powder streaking on the airplane too! :P
You can by dry graphite lubricant as well, might work for a puff of black.

George

My Feedback: (57)

VERY cool Ron!!

Video of that thing in action would be great.

drdoom

My Feedback: (9)

Powered Thermo ink for the old copier's. I use it to streak models. it will pretty much wipe off unless you heat it, with a hear gun. than it is permanent.

ChrisPetersen

My Feedback: (3)

That is one of the coolest ideas I've ever seen. But I think I would be worried about the graphite or chalk or whatever getting sucked into your turbine. I can't imagine it's gonna be too good on the bearings.

Ram-bro

My Feedback: (101)

whats the sound like?

Wren Turbines USA

My Feedback: (39)

No sound.........just tat-tat-tat

ddennison

My Feedback: (15)

Looks great Ron!

Any worries about all that powder going through the turbines?

Hope to see this working at Winamac!

Dave

Wren Turbines USA

My Feedback: (39)

The issue of the turbines ingesting the powder has been discussed, slept on, thought about...even drank a few beers trying to resolve the question. The protective screens on the Wren motors won't protect from the finer ground (ie: flour)...but I thought maybe a rough ground pepper may be heavy enough to fall below the engine level...with the hopper full of flour...the stuff REALLY comes out!! Any constructive ideas are welcome...as I would love to offer this idea to all the Hog owners.

I even thought about putting a smoke bomb in the hopper????

Only time and trial will tell!!

ddennison

My Feedback: (15)

HI Ron,

I only mention it as I recall in my reading that the full scale A10 during testing had episodes of engine stall during longer gun runs.
What I read was that this was due to the exhaust from the rounds being ingested (not an airflow issue).

SO I just thought that if the gun exhaust caused an issue in the full scale that it could be an issue. I dont want to be a kill joy.

I finally have mine back together with Details 4 Scale lights, Jet Tech tanks and a fresh new smile painted on the nose.

Dave

invertmast

My Feedback: (23)

I dont think the gun exhaust would be an issue, as the airflow from the bottom of the fuselage spilling over the sides infront of the wing will follow the upper contour of the wing airfoil and fall below the engine pods... atleasts thats what i'm thinking

ddennison

My Feedback: (15)

interesting reading..http://en.wikipedia.org/wiki/GAU-8_Avenger

ddennison

My Feedback: (15)

maybe this one will work? http://en.wikipedia.org/w/index.php?...r&id=359044116

starwoes

i thot the stall wasn't from the engine injesting the spent powder fumes but rather, an actual aerodynamic stall due to the powerful gun's recoil slowing down the aircraft's airspeed.....heard the airplane loses a few knots if u lay on the gun. could be wrong however.

ddennison

My Feedback: (15)

an excerpt

The A-10 engines were initially susceptible to flameout when subjected to gases generated in the firing of the gun. When the GAU-8 is being fired, the smoke from the gun can make the engines stop, and this did occur during initial flight testing.[2] Gun exhaust is essentially oxygen-free, and is certainly capable of causing flame-outs of gas turbines. The A-10 engines have a self sustaining combustion section. When the gun is fired the igniters come on to ensure no flame out occurs.[13]

Dave

starwoes

heard wrong then. good info...always thot of that gun as an overgrown monster to stall out a whole aircraft.

CraigG

My Feedback: (40)

Very cool. Sounds similar to the system on a crop duster a guy used to win Top Gun a year or so ago.

Not sure why you want a dark colored powder. The smoke trail from the real one is mostly white.

Craig

-JC-

My Feedback: (26)

Pretty cool stuff Ron.

Have you seen this one?


http://www.youtube.com/watch?v=xcuk8...=youtube_gdata

socshooter

My Feedback: (45)

Ron,
At any art store you can get graphite charcoal powder, thin enough to mix wit powder and or flour.

Great job.

Joe

geh3

My Feedback: (84)

Hey RON,My vote is for the

CraigG

My Feedback: (40)

Unfortunately the real GAU-8 has more of a loud "growl" than a rat-a-tat-tat sound. Listen to this:

http://www.youtube.com/watch?v=sALiuWg_I1k


Just wish somebody made a small and loud enough speaker to install inside the fuselage.

Craig

rbxbear44

My Feedback: (86)

Craig,
I have iFart on my iPhone and I think I know where they get the "greesy enchalada" one from

WOW!

Rex

myork

My Feedback: (3)

Very cool! It would be sweet if you could incorporate something like a progressive controller for nitrous systems. Instead of just opening the solenoid it will actually pulse the solenoid for whatever rate you program it vs the engines current RPM. Now I know there is no way you could cram a progressive controller in the a-10, but there has to be a DIY circuit out there that will pulse 12 volts to the solenoid. I'll do some digging around on the net and see if I can find one that will work. Most circuits like that use a 555 timer for the clock signal and a potentiometer to adjusted the rate of the pulse aka how fast it will fire.

EDIT: Found one that could work. Basically leave your servo operated switch in, but you don't want the cam function. You will just need off and on. Here is the diagram and a parts list

http://www.electronic-circuits-diagr...rsimages/1.gif

Parts list:

1 555 timer
1 1k ohm resistor
1 1M ohm potentiometer
2 0.01uF Capacitors

All of this should be available at your local radio shack