Air Trajectory B/C

[Sidvin]

It is PVC
I don't hear leaks
I have a Ping Pong Ball

[bernard]

It is PVC
I don't hear leaks
I have a Ping Pong Ball

What diameter PVC do you use (inner diameter)? How tight of a fit is your ping pong ball? I use 1.5-inch PVC with a ping pong ball and there are leaks unless I apply tape to the inside of the barrel.

[Sidvin]

So my diameter is 1.5 inch
My fit was horrible and I had to apply tape as well
I dealt with the problem by buying a rubber tube about 4 inches long that fit perfectly on top of the PVC. Fortunately, it held the ping pong ball perfectly and compressed it.

[bernard]

So my diameter is 1.5 inch
My fit was horrible and I had to apply tape as well
I dealt with the problem by buying a rubber tube about 4 inches long that fit perfectly on top of the PVC. Fortunately, it held the ping pong ball perfectly and compressed it.

Did your rubber tube go inside the PVC? I can't really tell from the description. If you used tape, were you careful to use the least amount of tape to stop leaks? For us we noticed that no tape gave it leaks, a perfect amount gave it no leaks and it would launch with a good amount of force, a lot of tape made it launch with too much force since the pressure built up, and too much tape stopped the ball from launching at all.

[Sidvin]

Tape was not working with us...
The rubber Tube fit on the outside of the PVC. WE simply slid it over the PVC and inserted the ball

[bernard]

Tape was not working with us...:(
The rubber Tube fit on the outside of the PVC. WE simply slid it over the PVC and inserted the ball

I don't understand why putting the rubber tube around the PVC would give the ball a tighter fit. Maybe a picture will help.

What tape did you try using? We used painters tape in short 1-inch strips.

[Sidvin]

We used Duct Tape and PVC Tape and Polypropylene Tape...
Btw, Im in 8th grade and entering HS Next yr...Your DD Records are GREAT!
In our regionals I placed second in it, but our B Team got 3rd. Our coach put them on the state team instead of me. I find it unfair since last year I place third in it at regionals as a B-Teamer and our A-Team got 2nd and he didn't put me on the state team.
Anyway, I'm going to state day after tm so I already had to take it to school to "pack"
Ill try to send a pic @ school

[bernard]

We used Duct Tape and PVC Tape and Polypropylene Tape...
Btw, Im in 8th grade and entering HS Next yr...Your DD Records are GREAT!
In our regionals I placed second in it, but our B Team got 3rd. Our coach put them on the state team instead of me. I find it unfair since last year I place third in it at regionals as a B-Teamer and our A-Team got 2nd and he didn't put me on the state team.
Anyway, I'm going to state day after tm so I already had to take it to school to "pack"
Ill try to send a pic @ school

DD Records? What state are you in?

I've never used PVC tape, but duct tape is probably too thick for giving a ping pong ball a slightly tighter fit.

[Sidvin]

By DD I mean Disease Detectives.
Yup...Duct Tape was too tough, rough and thick
From Tx

[bernard]

By DD I mean Disease Detectives.
Yup...Duct Tape was too tough, rough and thick
From Tx

Might have had a better record for it if we brought a study guide to the event at state - sigh.

If it isn't too much work or doesn't change your device too much, you might want to try blue painters tape or masking tape. Both have worked well for me.