Can any of you help me out.... I'm doing a project with my kids on bottle
rockets and need to find a couple of bored rubber bungs that will fit into
(and seal) a standard 2 LTR drinks bottle (like any of the ones sold filled
with fizzy pop)

I can't find anywhere locally to test this out and really need to find out
which size is best so that i can order them from the internet... can any of
you guys advise me... or even better, try this out and tell me the size I
need?

What would be extra useful is if you can also give me a tip as to where i
can order them from..?

I hope ypu can help as we have a couple of great designed rockets just
waiting to be launched...!!!

Thanks,


Mark Taylor

Mark:

I believe that a #3 bung fits a standard PET pop bottle. However, its
been quite a while since I tried it, and I don't have a #3 at home at
the moment.

Steve

If I may suggest:

Save the cap from the bottle. Bore it out with a small drill to fit
your tubing, remove the little blue plastic seal thingy and add some
epoxy or silicone to the inside and wait. Instant seal.

Mark Taylor wrote:
> Can any of you help me out.... I'm doing a project with my kids on bottle
> rockets and need to find a couple of bored rubber bungs that will fit into
> (and seal) a standard 2 LTR drinks bottle (like any of the ones sold filled
> with fizzy pop)
>
> I can't find anywhere locally to test this out and really need to find out
> which size is best so that i can order them from the internet... can any of
> you guys advise me... or even better, try this out and tell me the size I
> need?
>
> What would be extra useful is if you can also give me a tip as to where i
> can order them from..?
>
> I hope ypu can help as we have a couple of great designed rockets just
> waiting to be launched...!!!
>
> Thanks,
>
>
> Mark Taylor

Also consider the 3 liter PET bottles with the wider mouth that some
off-brand colas come in. I think a #6 or 7 stopper will fit.

Mark:

I remembered your question while I was i the store today, so I did
some testing.....

standard pop bottle....
#2 bung - much too small
#3 bung - very good fit
(to best of my knowledge, #2 1/2 & #3 1/2 do not exist)

the larger mouth pop bottle (I tested a 1 litre Aquafina bottle,
presume that others are the same mouth size)
#6 bung - OK
# 6 1/2 - better fit
#7 too big

Steve