- Joined
- Jan 19, 2009
- Messages
- 3,453
- Reaction score
- 1,338
Yes, I am expecting the title to attract attention and comments.
I'm not certain this is kosher, but I ran into a problem on my Tri-Trident thread and have not seen any suggestions, so I decided to start another thread to discuss the specific issue.
The Tri-Trident is an attempt to make a triangular based, ducted ejection, similar to the original Estes Trident kit.
So I plagiarized a bit from my other thread to explain things...
NOTE - these were test pieces to try before doing the real rocket
And to complicate it, I'm trying to mate the tubes angle to angle.
Multiple launch lugs will be used as "pipes" to connect the small outer tubes to the larger central tube (shown in blue). The joint will be reinforced with rocketpoxy (reddish) and a vertical matboard (green)
The launch lugs glues up as "pan pipes"
Notched the tubes and installed the pan pipes
Reinforced with the poxy and matboard
Now for the issue.....
I tried blocking the one end of the small tube and blew into the other end. I could not get air to move through the pipes.
OK - maybe I messed up and got glue or poxy in the pipes.
So I decided to cut open the large tube to look.
Appears clear. If you look closely, you can see the purple exacto handle I held in the other tube
I can even pass a file handle through all 6 pipes
So the pipes are open. But still, if I block one end of the small tube and blow into the other end of the small tube, the air does NOT go into the large tube!
I also tried the opposite direction. Blocked one end plus the cutout on the large tube and blew into the other end. When I maintained a good seal on both openings, no air moved.
From my point of view, this violates multiple physics and engineering principles.
But I can't figure out what the heck is going on!!
With the one end blocked and blowing air into the other end, I am pressurizing the small tube. The higher pressure should bleed through the pipes into the larger tube.
Oh - I also grabbed a loose lug and blew through it like a straw. Lots of air moved. With 6, I would expect even more to move.
WHAT AM I MISSING?
Is it time to hang up my slide rule???
I'm not certain this is kosher, but I ran into a problem on my Tri-Trident thread and have not seen any suggestions, so I decided to start another thread to discuss the specific issue.
The Tri-Trident is an attempt to make a triangular based, ducted ejection, similar to the original Estes Trident kit.
So I plagiarized a bit from my other thread to explain things...
NOTE - these were test pieces to try before doing the real rocket
And to complicate it, I'm trying to mate the tubes angle to angle.
Multiple launch lugs will be used as "pipes" to connect the small outer tubes to the larger central tube (shown in blue). The joint will be reinforced with rocketpoxy (reddish) and a vertical matboard (green)
The launch lugs glues up as "pan pipes"
Notched the tubes and installed the pan pipes
Reinforced with the poxy and matboard
Now for the issue.....
I tried blocking the one end of the small tube and blew into the other end. I could not get air to move through the pipes.
OK - maybe I messed up and got glue or poxy in the pipes.
So I decided to cut open the large tube to look.
Appears clear. If you look closely, you can see the purple exacto handle I held in the other tube
I can even pass a file handle through all 6 pipes
So the pipes are open. But still, if I block one end of the small tube and blow into the other end of the small tube, the air does NOT go into the large tube!
I also tried the opposite direction. Blocked one end plus the cutout on the large tube and blew into the other end. When I maintained a good seal on both openings, no air moved.
From my point of view, this violates multiple physics and engineering principles.
But I can't figure out what the heck is going on!!
With the one end blocked and blowing air into the other end, I am pressurizing the small tube. The higher pressure should bleed through the pipes into the larger tube.
Oh - I also grabbed a loose lug and blew through it like a straw. Lots of air moved. With 6, I would expect even more to move.
WHAT AM I MISSING?
Is it time to hang up my slide rule???