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  #11  
Old 01-03-2011, 10:18 PM
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Flyguytki Flyguytki is offline
 
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Originally Posted by PerfTech View Post
Thank you David for the kind words! If we get enough interest in the system I may offer some for sale but if you want to build your own I am more than happy to supply any and all available info to you or anyone else who may be interested. Regards, Allan
Definatly very interested in that list so make sure I'm at the top when you do put it out!! Thanks alot!

-david
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  #12  
Old 01-03-2011, 10:36 PM
gasman gasman is offline
 
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Looks like a nice system. I would purchase one. Where do we send the check?
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  #13  
Old 01-03-2011, 10:49 PM
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PerfTech PerfTech is offline
 
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Originally Posted by Snowflake View Post
I like the integration of the system into the tank. I have concerns about a four pound system plus four gallons of oil being held in place with just that spring. Although you're in a -9 so inverted manoeuvers aren't likely. What happens if the vent gets wet from the inside? Could it handle a roll and then start venting again afterwards?
The vent has a ball bearing gravity check valve under the bronze filter that closes if the tank is put on its side or is inverted. Also the check valve will let air in when the smoke is on even if inverted. The hold down spring is very strong but if I were going to do negative maneuvers I would install a over center latch system. I used the spring on this one as it easily comes out spring and all.
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  #14  
Old 01-04-2011, 04:36 PM
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PerfTech PerfTech is offline
 
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Default A few answers!!!!!

First I would like to say that it's nice to see someone that is happy with a purchase they made and is willing to support their supplier as you have. I will attempt to answer your concerns, as they may be of interest to other Van's owners considering smoke.

1. I don't believe the 25 minute job of removing a couple of exhaust pipes and welding on a fitting is too difficult for someone who built their airplane. I consider a .50 cent hose clamp holding in the oil nozzles somewhat irresponsible. Were this clamp to fail or vibrate loose you run the risk of spraying oil on red hot exhaust pipes. This will virtually guarantee a potentially fatal in-flight fire. The .50 cent clamp is OK for an EGT with minimal fire potential, not for flammable material in my plane.

2. As for the mounting of the tank it has a 1/8" safety cable inside the spring that would have to fail for the tank to become dislodged. By my calculations, with the tank full this would require 30+ G's. Not a concern!

3. The system has an adjustable pressure bypass built into the bottom of the billet cap assembly. This can accommodate any flow rate from .3 GPM up to 1.4 GPM.

4. Attached to the pump inlet is a very fine pickup screen that filters out any particles or debris over 20 microns in size. Also unlike an inline filter, every time you pull the assembly you have the opportunity to observe and clean it.

5. I have addressed the vent design and vent check valve in a previous post, but If I were doing hard negative aerobatics I would add a spiral overboard vent to the existing one.

6. As for your reservations concerning the pump, they are completely unfounded and stem from lack of being informed. If you drive a automobile less than 30 years of age that has fuel injection this submersible gas tank mounted pump is what makes it go. These rotocell high pressure pumps are in virtually every automobile gas tank. They are designed to function at maximum flow, continuously for over 150,000 miles, submerged in gasoline the entire time. The one I am using is the top of the line Walboro High Performance model. The lifespan and reliability of this unit will be many times that of the one you compared it to.

As for deflating my ambitions, I really don't have any in regards to the item in discussion. I do this for fun and relaxation not for any other reason. Money isn't one of my problems. The few systems that I build will most likely be given no charge to close friends and associates that I fly with. I have been flying for 40 years, have owned and flown most of the worlds finest aerobatic planes. I have explored I am sure my experimental options, racing formula one at Reno, aerobatic competitions and demonstrations all over the world, participation in countless airshows, was partnered with Art Scholl and Chuck Wentworth for many years. I probably have logged more hours of aerobatics with smoke than most pilots have hours. My ambitions are to enjoy life and surround myself with well informed people that feel the same. Regards, Allan

PS. Should you decide you would like to upgrade your system I would make you a very special deal!!!!

Last edited by PerfTech : 01-06-2011 at 09:22 PM. Reason: Remove potenyualy rude statment
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  #15  
Old 01-04-2011, 05:38 PM
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PerfTech PerfTech is offline
 
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Who says stuff like this? Rude.
Perhaps you are correct and I apologize for the rudeness.
I have edited the post and removed the statement. Thank you for your honesty.Cheers, Allan
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  #16  
Old 01-04-2011, 05:41 PM
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rocketbob rocketbob is offline
 
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I'm curious about how you came up with the nozzle design. I decided long ago to use a 120psi Carter fuel pump for the smoke system in my rocket, since I have one laying around. Most smoke systems are based on cheap low pressure water pumps used in RV's (of the recreational vehicle kind.), which just dump fuel into the exhaust. For the injector nozzle mine will be a little different, using three small holes on a conical face. Just like a diesel injector. I think it will work better as far as atomization goes.

Certainly simplifies things having a ball check in the injector like you have done.

Why not go higher up the pipe with the nozzle?
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N9187P PA-24-260B Comanche, flying
N678X F1 Rocket, under const.
N244BJ RV-6 "victim of SNF tornado" 1200+ hrs, rebuilding
N8155F C150 flying
N7925P PA-24-250 Comanche, restoring
Not a thing I own is stock.

Last edited by rocketbob : 01-04-2011 at 05:46 PM.
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  #17  
Old 01-04-2011, 05:44 PM
szicree szicree is offline
 
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I removed my post as well. No point in stirring the pot. Incidently, your system looks real nice and the submerged pump is the best part. Innovation and competition are what its all about.
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  #18  
Old 01-04-2011, 06:45 PM
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PerfTech PerfTech is offline
 
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Quote:
Originally Posted by rocketbob View Post
I'm curious about how you came up with the nozzle design. I decided long ago to use a 120psi Carter fuel pump for the smoke system in my rocket, since I have one laying around. Most smoke systems are based on cheap low pressure water pumps used in RV's (of the recreational vehicle kind.), which just dump fuel into the exhaust. For the injector nozzle mine will be a little different, using three small holes on a conical face. Just like a diesel injector. I think it will work better as far as atomization goes.

Certainly simplifies things having a ball check in the injector like you have done.

Why not go higher up the pipe with the nozzle?
I decided on this design after quite a lot of experimentation with different spray patterns. Anything will work but the finer you can atomize the oil the better the smoke Having one hole is easier to make and control than multiple holes. The stream contacts the wedge and fans out to 180 Deg. spray pattern that for me worked better than all others I tried. You ask about moving the nozzle further up the pipe and it doe's work but produces a very different looking smoke pattern. The smoke resembles a giant string of pearls in the sky from each pipe. The reason for this is very simple, the four stroke engine only duplicates an exhaust cycle once every 720 deg. of rotation. This exhaust valve opening lasts aprox. 210 deg. of which only 100 deg. is effective exhaust flow that can evacuate the pipe. The smoke system is injecting oil into the pipe continuously so 1&3/4 rotation of the engine the pipe is being charged with oil and only being expelled about 12% of the time thus producing the puffing or smoke balls. The more cylinders you have working on the oil spray the more and smoother the smoke. If you are interested I can send you a link to the stainless spray heads I started with to produce my nozzles. The pump you were going to use should work very well as they are a quality unit designed for petroleum products. I am not a fan of using a water pump intended for a camper to pump flammable liquids ether. Thank you for your interest, Allan
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  #19  
Old 01-04-2011, 07:26 PM
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rocketbob rocketbob is offline
 
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Quote:
Originally Posted by PerfTech View Post
I decided on this design after quite a lot of experimentation with different spray patterns. Anything will work but the finer you can atomize the oil the better the smoke Having one hole is easier to make and control than multiple holes. The stream contacts the wedge and fans out to 180 Deg. spray pattern that for me worked better than all others I tried. You ask about moving the nozzle further up the pipe and it doe's work but produces a very different looking smoke pattern. The smoke resembles a giant string of pearls in the sky from each pipe. The reason for this is very simple, the four stroke engine only duplicates an exhaust cycle once every 720 deg. of rotation. This exhaust valve opening lasts aprox. 210 deg. of which only 100 deg. is effective exhaust flow that can evacuate the pipe. The smoke system is injecting oil into the pipe continuously so 1&3/4 rotation of the engine the pipe is being charged with oil and only being expelled about 12% of the time thus producing the puffing or smoke balls. The more cylinders you have working on the oil spray the more and smoother the smoke. If you are interested I can send you a link to the stainless spray heads I started with to produce my nozzles. The pump you were going to use should work very well as they are a quality unit designed for petroleum products. I am not a fan of using a water pump intended for a camper to pump flammable liquids ether. Thank you for your interest, Allan
Makes perfect sense. Yes please send me the link. rocketbob@gmail.com
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Bob Japundza CFI A&PIA
N9187P PA-24-260B Comanche, flying
N678X F1 Rocket, under const.
N244BJ RV-6 "victim of SNF tornado" 1200+ hrs, rebuilding
N8155F C150 flying
N7925P PA-24-250 Comanche, restoring
Not a thing I own is stock.
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  #20  
Old 01-04-2011, 07:34 PM
131RB 131RB is offline
 
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Allan,
First just wanted to say thanks for the post and the pictures. I see that some of the previous posts have been removed. It can be challanging at times throwing something out there for people to scrutinize. One of the things I like about experimental aviation is we can collect all the best ideas in our opinion and build something in our own image. Your post along with the smoke system on a budget post has given me many ideas for my own system. I really like the idea of the welded boses on the exhaust pipes and I also really like the idea of the pump being in the tank. I like the ideas of the check valves as well. If you choose to give up your source for the can and pump I would be interested.
Once again
Thanks,
Ryan
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