ducted fan fuel and thrust ?'s
#1
Thread Starter
ducted fan fuel and thrust ?'s
Hello... I am building the RCM Phantom (1076), and I have a couple of questions.
1. Is a hopper tank needed? And if so, what is it's purpose???
2. How do you make homemade thrust tubes???
Thanks...
1. Is a hopper tank needed? And if so, what is it's purpose???
2. How do you make homemade thrust tubes???
Thanks...
#2
My Feedback: (101)
RE: ducted fan fuel and thrust ?'s
I have never used a hopper tank on my Byron setups. I believe it was a way to keep a full line free of airbubbles going to the carb....I may be wrong though. I have never made a thrust tube. I have always used mylar . The way the fiberglass tubes are made is to on a glass surface was to layout some glass cloth and glass(epoxy or resin). After it has cured you would roll it into the size tube and glue it. They dont seem to last as long as the mylar but you know you can make it. I am not sure where you can get the mylar. Byron/Iron bay may hae some. I have extra thrust tubes for my Byron F15....but I am not sure I would give them up.....
#4
My Feedback: (29)
RE: ducted fan fuel and thrust ?'s
I have made a few bifurcated thrust tubes for a couple of different DFs. I built the bi-tubes in a jig. I rolled 1/64th plywood to make the tubes. One end of the jig has a large hole (little larger than 5.25”) and the other end has 2 holes (each one is slightly larger than 2 5/8”) You take some measurements from your airframe to get the length and spacing of the holes.
Roll the 1/64th ply through the large hole and then through one of the small holes. You want enough ply rolled in the jig to overlap an imaginary line running right down the center of the jig. So you end up with a cone on the small end and the large hole on the other end in just over half covered. Now roll some 1/64th ply through the big hole and into the remaining small hole. Make sure you have at least a ¼” over lap everywhere. Once your satisfied with the fit use CA to glue it all together. Try to avoid gluing the pipe into the jig but it’s not a big deal if you have to cut it loose later. Once it’s all glued, you will probably need to use a dremel to clean up the joint where the 2 tubes join together inside. Then you will need to paint the inside to seal it from oil.
Roll the 1/64th ply through the large hole and then through one of the small holes. You want enough ply rolled in the jig to overlap an imaginary line running right down the center of the jig. So you end up with a cone on the small end and the large hole on the other end in just over half covered. Now roll some 1/64th ply through the big hole and into the remaining small hole. Make sure you have at least a ¼” over lap everywhere. Once your satisfied with the fit use CA to glue it all together. Try to avoid gluing the pipe into the jig but it’s not a big deal if you have to cut it loose later. Once it’s all glued, you will probably need to use a dremel to clean up the joint where the 2 tubes join together inside. Then you will need to paint the inside to seal it from oil.
#5
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RE: ducted fan fuel and thrust ?'s
I mould the tubes over a plug. Tube on pic is for a Boss unit but i did the same for my byron unit in my Vampire!
Seems to take the punishment!
Jonas
Seems to take the punishment!
Jonas
#6
RE: ducted fan fuel and thrust ?'s
i did use a hopper tank on my DFs, kept the mixture from leaning as the tank gets low and vibration foams the fuel up. on my Byron setups i used the Byron system, it had the hopper built into it.
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RE: ducted fan fuel and thrust ?'s
ORIGINAL: ductedfan
Hello... I am building the RCM Phantom (1076), and I have a couple of questions.
1. Is a hopper tank needed? And if so, what is it's purpose???
2. How do you make homemade thrust tubes???
Thanks...
Hello... I am building the RCM Phantom (1076), and I have a couple of questions.
1. Is a hopper tank needed? And if so, what is it's purpose???
2. How do you make homemade thrust tubes???
Thanks...
I started using a small hopper on my DF many years ago. Sometimes, when doing slow rolls, point rolls, snaps, etc and the main fuel is a half or lower, you can pick up an air bubble, get a burp in the engine or have the engine quit. Hopper eliminates that problem and reduces the chance of mixture changes as the main fuel runs low. The carb only knows from where it comes, the full hopper. BVM used hoppers years ago.
#9
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RE: ducted fan fuel and thrust ?'s
ORIGINAL: Ram-bro
I have never used a hopper tank on my Byron setups. I believe it was a way to keep a full line free of airbubbles going to the carb....I may be wrong though. I have never made a thrust tube. I have always used mylar . The way the fiberglass tubes are made is to on a glass surface was to layout some glass cloth and glass(epoxy or resin). After it has cured you would roll it into the size tube and glue it. They dont seem to last as long as the mylar but you know you can make it. I am not sure where you can get the mylar. Byron/Iron bay may hae some. I have extra thrust tubes for my Byron F15....but I am not sure I would give them up.....
I have never used a hopper tank on my Byron setups. I believe it was a way to keep a full line free of airbubbles going to the carb....I may be wrong though. I have never made a thrust tube. I have always used mylar . The way the fiberglass tubes are made is to on a glass surface was to layout some glass cloth and glass(epoxy or resin). After it has cured you would roll it into the size tube and glue it. They dont seem to last as long as the mylar but you know you can make it. I am not sure where you can get the mylar. Byron/Iron bay may hae some. I have extra thrust tubes for my Byron F15....but I am not sure I would give them up.....
jackjet