Forgive a possibly naive question, but does anyone make a tap to allow me to
thread a hole to screw in a bottle - perhaps a soda bottle size thread?
Thanks for any input.

Mark

8 TPI, 1" min diameter, 1.08" max diameter. The thread form is rounded
like an acme thread although I don't know if it's exactly the same.

For backyard-type experiments, the most common method to attach
plumbing is to drill the hole in a bottlecap and put a Schrader (tire)
valve in there. From there you can adapt to whatever you want.

Tim.

"Tim Shoppa" wrote in message
ups.com...
8 TPI, 1" min diameter, 1.08" max diameter. The thread form is rounded
like an acme thread although I don't know if it's exactly the same.

For backyard-type experiments, the most common method to attach
plumbing is to drill the hole in a bottlecap and put a Schrader (tire)
valve in there. From there you can adapt to whatever you want.

Tim.

Thanks for the info, Tim, but what I want to do is screw a glass bottle into
a plastic manifold. I want to know if I can buy a tap to tap the hole, or do
the threads have to be cut manually on a lathe?

Mark

You know, making silencers can get you in big trouble. The two liter
bottle works quite well for handguns up to .38 cal. but tends to blow
off of high power rifles. Good luck.

On 2 Jun 2005 07:53:31 -0700, Gary wrote:
You know, making silencers can get you in big trouble. The two liter
bottle works quite well for handguns up to .38 cal. but tends to blow
off of high power rifles. Good luck.

He's talking about a glass bottle, so while your guess wasn't a bad one
with the information you had, it's probably no the case here, given the
new details.

Nothing nefarious intended - it's for a piece of medical equipment to be
used in Veterinary medicine. I'm not going to actually use a soda bottle,
but I will (might) be using a bottle with the same thread.

Mark

"Dave Hinz" wrote in message
...
On 2 Jun 2005 07:53:31 -0700, Gary wrote:
You know, making silencers can get you in big trouble. The two liter
bottle works quite well for handguns up to .38 cal. but tends to blow
off of high power rifles. Good luck.

He's talking about a glass bottle, so while your guess wasn't a bad one
with the information you had, it's probably no the case here, given the
new details.

but I will (might) be using a glass
bottle with the same thread.

I am not a bottling expert, but my impression is that a glass bottle
threading into an aluminum threaded hole will not seal at all.

The seal on most bottle caps depends on the top of the bottle pushing
up against the inside of the cap. In an aluminum manifold hole cut
with a tap, you won't have anything to push up against and seal. If
you put in a backing plate with hole in after tapping the hole and have
a rubber/plastic seal, it might work. But really, all applicatins I
see doing this just drill a hole in a regular plastic bottlecap and put
a tire valve in.

The bottlecap thread does not taper like a usual pipe thread, so the
thread itself provides no seal. The thread just provides the pressure
to form the seal at the top of the bottle opening.

Tim.

On 2 Jun 2005 08:32:57 -0700, Tim Shoppa wrote:

I am not a bottling expert, but my impression is that a glass bottle
threading into an aluminum threaded hole will not seal at all.

How about using a garden-hose thread rather than a soda bottle thread?
Those gaskets are _really_ cheap and effective for both pressure and,
I'd imagine, suction. Fittings can be bought at any decent hardware
store as well, for either side of the connection.

Another thought - maybe googling for home brewing supplies might give
you a convenient place to buy what you're looking for?

Dave Hinz

I suggest using a threaded insert in the manifold, held by epoxy. If you
want something more rugged than a used bottle cap, shop for some of those
screw-on plant watering attachments.

How about using a garden-hose thread rather
than a soda bottle thread? Those gaskets are _really_
cheap and effective for both pressure and,
I'd imagine, suction.

In fact, I have used garden-hose gaskets for some backyard experiments
with soda bottles. They are pretty much an exact fit.

(One such experiment is to fill the bottom half inch or so of the soda
bottle with liquid nitrogen, screw a pressure gauge and seal on the
top, and then run away and watch the pressure gauge with binoculars to
determine the pressure at which the bottle explodes (circa 150 PSI). I
think I documented these experiments back in the 90's, probably on this
same newsgroup!)

I think the thread diameters are very similar, but a soda bottle is
8TPI vs a garden hose's 11.5TPI.

Tim.

On 2 Jun 2005 10:45:17 -0700, Tim Shoppa wrote:
How about using a garden-hose thread rather
than a soda bottle thread? Those gaskets are _really_
cheap and effective for both pressure and,
I'd imagine, suction.

In fact, I have used garden-hose gaskets for some backyard experiments
with soda bottles. They are pretty much an exact fit.

I kind of thought they might be, but I'm not near a garden hose at the
moment.

I think the thread diameters are very similar, but a soda bottle is
8TPI vs a garden hose's 11.5TPI.

Seems like a not-very-good fit from here?

Seems like a not-very-good fit from here?

Certainly the threads don't mesh. But the gaskets seem fine. (I might
have had to whittle away the edge of the garden hose gasket to get it
to fit my bottle-top plumbing, but maybe not! IIRC a knife was already
in use for adapting the pressure gauge to the bottle top.)

On Thu, 02 Jun 2005 13:48:48 GMT, "Mark"
wrote:

Forgive a possibly naive question, but does anyone make a tap to allow me to
thread a hole to screw in a bottle - perhaps a soda bottle size thread?
Thanks for any input.

I think a tap might be hard to find, but it's easy to make a bottle
cap on a lathe. Use Delryn (an acetyl engineering plastic) rod as
rawstock. I do it by hand rather than under power.

I think the threadform is closer to half-round than V or Acme. It
is on PET (plastic) bottles. I don't have a glass bottle to look at.

"Mark" wrote in message
link.net...
Forgive a possibly naive question, but does anyone make a tap to allow me
to
thread a hole to screw in a bottle - perhaps a soda bottle size thread?
Thanks for any input.

Mark



That's what I like. A detailed and precise specification!

Tom

Mark,

To the best of my knowledge, you won't find a tap for a bottle cap. Bottles
are made with the thread molded of course.
The caps, if metal, have the threads rolled into them using very
sophisticated equipment and involving several
operations. I 'believe' plastic caps are again molded with the threads.

Each manufacturer of the bottle/cap combination has their own thread
specifications, some of which are 'standard'
to the industry.

Good luck!
"Mark" wrote in message
link.net...
Forgive a possibly naive question, but does anyone make a tap to allow me
to
thread a hole to screw in a bottle - perhaps a soda bottle size thread?
Thanks for any input.

Mark

Can you drill out an oversize hole and epoxy in a plastic bottle
cap to receive the bottle?

(top posted for your convenience)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Keep the whole world singing . . . .
DanG (remove the sevens)




"Mark" wrote in message
link.net...
Forgive a possibly naive question, but does anyone make a tap to
allow me to
thread a hole to screw in a bottle - perhaps a soda bottle size
thread?
Thanks for any input.

Mark

In article .net,
"Mark" wrote:

"Tim Shoppa" wrote in message
ups.com...
8 TPI, 1" min diameter, 1.08" max diameter. The thread form is rounded
like an acme thread although I don't know if it's exactly the same.

For backyard-type experiments, the most common method to attach
plumbing is to drill the hole in a bottlecap and put a Schrader (tire)
valve in there. From there you can adapt to whatever you want.

Tim.

Thanks for the info, Tim, but what I want to do is screw a glass bottle into
a plastic manifold. I want to know if I can buy a tap to tap the hole, or do
the threads have to be cut manually on a lathe?

Probably easier to make a tap on the lathe then cut the threads into
plastic.

--
Free men own guns, slaves don't
www.geocities.com/CapitolHill/5357/

I did some research on this and found this site:
http://www.plasticsindustry.org/business/literatu.htm

Most of the documents are available as free pdf downloads, look at:
http://www.plasticsindustry.org/busi...atu.htm#AU-103
especially:
catalog number AU-124 if my memory serves...