What size inner tube will produce rubber bands with 8" diameter?

Can anyone tell me the formula for calculating the inside diameter of
the air chamber in an inner tube when inflated to just full (not
over-inflated as they do for river tubing).

We recently replaced our asphalt driveway with pavers. It looks great,
but the trash bins now make an unholy racket when I roll them down the
driveway to the curb. I usually do this late at night or very early in
the morning, so the racket is annoying to us and to the neighbors.

My solution is to cut rubber bands (3-4" wide) from an inner tube and
stretch them over the hard plastic wheels.

I bought a Slime 5001-A inner tube from a local auto parts store that
is labeled "700/750 R15/16". I've seen these tubes inflated to several
times their normal size for tubing, so I figured it would work. I cut
one band from the tube and discovered that it only has a diameter of
about 5". I couldn't stretch it enough to get it onto the wheel.

In retrospect, I should have inflated the tube as large as possible
and let it sit for a few days to stretch it out, but it's too late for
that now. I'm not even sure that would have worked. I could go buy
another tube and do that. Does anyone know how much I'd have to
inflate it and how I'd have to leave it to ghet it stretched out
enough?

Does anyone have another suggestion for a way to stretch a very stiff
5" rubber band to fit over a 10" wheel?

If not, I need a larger inner tube. The question is, what size tube
should I look for?

When the 700/750 R15/16 is deflated and laid flat, the tube rubber is
just under 8" wide. That is, the rubber band I cut from that tube is
just under 8" long. If formed into a circle, the circle has a
circumference of just under 16" (2 x 8), which makes a circle with a
diameter of just under 5". (C = 2*pi*r = pi*d so d = C/pi).

I think I need a rubber band with a diameter of about 8-9". That would
make it possible for me to stretch the band over the tire, but still
make it tight enough to stay on.

If my geometry isn't too rusty, I will need a tube with an air chamber
that is between 13-14" wide when deflated and laid flat. A band cut
from such a tube would have a circumference of twice that (26-28") and
a diameter of 8-9".

What size tube is that in standard tire designations?

Any suggestions for where I should go to get a used or discarded tube?

"Prof Wonmug" wrote in message
> Can anyone tell me the formula for calculating the inside diameter
> of
> the air chamber in an inner tube when inflated to just full (not
> over-inflated as they do for river tubing).
>
> We recently replaced our asphalt driveway with pavers. It looks
> great,
> but the trash bins now make an unholy racket when I roll them down
> the
> driveway to the curb. I usually do this late at night or very early
> in
> the morning, so the racket is annoying to us and to the neighbors.
>
> My solution is to cut rubber bands (3-4" wide) from an inner tube
> and
> stretch them over the hard plastic wheels...
>

Perhaps a cart with inflated tires would be a better solution? Like
this...
http://www.northerntool.com/shop/too...8174_200198174

Prof Wonmug > wrote in
:

> Can anyone tell me the formula for calculating the inside diameter of
> the air chamber in an inner tube when inflated to just full (not
> over-inflated as they do for river tubing).



Call a truck/tractor/farm-equipment place. They'll know what you need right
away.




--
Tegger

Prof Wonmug wrote:
> Can anyone tell me the formula for calculating the inside diameter of
> the air chamber in an inner tube when inflated to just full (not
> over-inflated as they do for river tubing).
>
> We recently replaced our asphalt driveway with pavers. It looks great,
> but the trash bins now make an unholy racket when I roll them down the
> driveway to the curb. I usually do this late at night or very early in
> the morning, so the racket is annoying to us and to the neighbors.
>
> My solution is to cut rubber bands (3-4" wide) from an inner tube and
> stretch them over the hard plastic wheels.
>
> I bought a Slime 5001-A inner tube from a local auto parts store that
> is labeled "700/750 R15/16". I've seen these tubes inflated to several
> times their normal size for tubing, so I figured it would work. I cut
> one band from the tube and discovered that it only has a diameter of
> about 5". I couldn't stretch it enough to get it onto the wheel.
>
> In retrospect, I should have inflated the tube as large as possible
> and let it sit for a few days to stretch it out, but it's too late for
> that now. I'm not even sure that would have worked. I could go buy
> another tube and do that. Does anyone know how much I'd have to
> inflate it and how I'd have to leave it to ghet it stretched out
> enough?
>
> Does anyone have another suggestion for a way to stretch a very stiff
> 5" rubber band to fit over a 10" wheel?
>
> If not, I need a larger inner tube. The question is, what size tube
> should I look for?
>
> When the 700/750 R15/16 is deflated and laid flat, the tube rubber is
> just under 8" wide. That is, the rubber band I cut from that tube is
> just under 8" long. If formed into a circle, the circle has a
> circumference of just under 16" (2 x 8), which makes a circle with a
> diameter of just under 5". (C = 2*pi*r = pi*d so d = C/pi).
>
> I think I need a rubber band with a diameter of about 8-9". That would
> make it possible for me to stretch the band over the tire, but still
> make it tight enough to stay on.
>
> If my geometry isn't too rusty, I will need a tube with an air chamber
> that is between 13-14" wide when deflated and laid flat. A band cut
> from such a tube would have a circumference of twice that (26-28") and
> a diameter of 8-9".
>
> What size tube is that in standard tire designations?
>
> Any suggestions for where I should go to get a used or discarded tube?


I generally dislike duct tape and its many wayward
applications, but I think a few turns of it may do it in
this case.

--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971

On 2011-02-14, Prof Wonmug > wrote:
> Can anyone tell me the formula for calculating the inside diameter of
> the air chamber in an inner tube when inflated to just full (not
> over-inflated as they do for river tubing).
>
> We recently replaced our asphalt driveway with pavers. It looks great,
> but the trash bins now make an unholy racket when I roll them down the
> driveway to the curb. I usually do this late at night or very early in
> the morning, so the racket is annoying to us and to the neighbors.
>
> My solution is to cut rubber bands (3-4" wide) from an inner tube and
> stretch them over the hard plastic wheels.
>
> I bought a Slime 5001-A inner tube from a local auto parts store that
> is labeled "700/750 R15/16". I've seen these tubes inflated to several
> times their normal size for tubing, so I figured it would work. I cut
> one band from the tube and discovered that it only has a diameter of
> about 5". I couldn't stretch it enough to get it onto the wheel.
>
> In retrospect, I should have inflated the tube as large as possible
> and let it sit for a few days to stretch it out, but it's too late for
> that now. I'm not even sure that would have worked. I could go buy
> another tube and do that. Does anyone know how much I'd have to
> inflate it and how I'd have to leave it to ghet it stretched out
> enough?
>
> Does anyone have another suggestion for a way to stretch a very stiff
> 5" rubber band to fit over a 10" wheel?
>
> If not, I need a larger inner tube. The question is, what size tube
> should I look for?
>
> When the 700/750 R15/16 is deflated and laid flat, the tube rubber is
> just under 8" wide. That is, the rubber band I cut from that tube is
> just under 8" long. If formed into a circle, the circle has a
> circumference of just under 16" (2 x 8), which makes a circle with a
> diameter of just under 5". (C = 2*pi*r = pi*d so d = C/pi).

> I think I need a rubber band with a diameter of about 8-9". That would
> make it possible for me to stretch the band over the tire, but still
> make it tight enough to stay on.
>
> If my geometry isn't too rusty, I will need a tube with an air chamber
> that is between 13-14" wide when deflated and laid flat. A band cut
> from such a tube would have a circumference of twice that (26-28") and
> a diameter of 8-9".
>
> What size tube is that in standard tire designations?
>
> Any suggestions for where I should go to get a used or discarded tube?

Harbor freight has a wide assortment of cheap wheels/tires that should
work well...

http://www.harborfreight.com/

http://www.harborfreight.com/media/13.jpg

That's probably less than you paid for the innertube.

On Mon, 14 Feb 2011 23:37:00 +0000 (UTC), Tegger >
wrote:

>Prof Wonmug > wrote in
:
>
>> Can anyone tell me the formula for calculating the inside diameter of
>> the air chamber in an inner tube when inflated to just full (not
>> over-inflated as they do for river tubing).
>
>Call a truck/tractor/farm-equipment place. They'll know what you need right
>away.

I called 2-3 tire dealers. None of them could tell me how to determine
the cross section of the air chamber from the numbers on the tube box.
I guess they don't work that way.

I bought a tube labeled 700/750 R15/16. I thought it might fit because
the tires on my car are about 8" wide and 6" thick (rim to tread). It
was way too tight. The bands had a diameter of just under 5", which
meant I had to stretch it to double it's resting size. I couldn't do
it. Apparently the tubes are designed to be about 30-50% smaller than
the inside of the tire.

Then I realized that the width (W) of the air chamber when the
deflated tube is laid flat is just half of the circumference (C),
which means I can calculate the diameter (D):

D = C/pi = 2*W/pi

The width of the tube I bought was about 7.75", so

D = 2 * 7.75 / pi = 4.93

Which is about right.

Based on how hard it was to stretch the car tube from a 5" diameter to
a 10" diameter, I figure I need a tube that will yield bands with a
diameter between 8" and 9". But I don't know how to calculate the band
sized from the numbers on the tube. So I made a little spreadsheet to
calculate the diameters from the widths planning to go to a tire store
and measure. Here's the table

width
(C/2) diameter
6.28 4.00
7.75 4.93 The auto tube (700/750 R15/16)
7.85 5.00
9.42 6.00
11.00 7.00
12.50 7.96 A R20-1400 tube at one tire dealer
12.57 8.00
13.35 8.50
14.14 9.00 Upper limit on size
14.92 9.50
15.71 10.00
17.00 10.82 A R24 tube at one tire dealer

I found an R20 and an R24 tube at one dealer. The R24 is too big. The
R20 might be too small. I have one more place to try for an R22./

On Mon, 14 Feb 2011 17:39:08 -0600, AMuzi > wrote:

>Prof Wonmug wrote:
>> Can anyone tell me the formula for calculating the inside diameter of
>> the air chamber in an inner tube when inflated to just full (not
>> over-inflated as they do for river tubing).
>>
>> We recently replaced our asphalt driveway with pavers. It looks great,
>> but the trash bins now make an unholy racket when I roll them down the
>> driveway to the curb. I usually do this late at night or very early in
>> the morning, so the racket is annoying to us and to the neighbors.
>>
>> My solution is to cut rubber bands (3-4" wide) from an inner tube and
>> stretch them over the hard plastic wheels.
>>
>> I bought a Slime 5001-A inner tube from a local auto parts store that
>> is labeled "700/750 R15/16". I've seen these tubes inflated to several
>> times their normal size for tubing, so I figured it would work. I cut
>> one band from the tube and discovered that it only has a diameter of
>> about 5". I couldn't stretch it enough to get it onto the wheel.
>>
>> In retrospect, I should have inflated the tube as large as possible
>> and let it sit for a few days to stretch it out, but it's too late for
>> that now. I'm not even sure that would have worked. I could go buy
>> another tube and do that. Does anyone know how much I'd have to
>> inflate it and how I'd have to leave it to ghet it stretched out
>> enough?
>>
>> Does anyone have another suggestion for a way to stretch a very stiff
>> 5" rubber band to fit over a 10" wheel?
>>
>> If not, I need a larger inner tube. The question is, what size tube
>> should I look for?
>>
>> When the 700/750 R15/16 is deflated and laid flat, the tube rubber is
>> just under 8" wide. That is, the rubber band I cut from that tube is
>> just under 8" long. If formed into a circle, the circle has a
>> circumference of just under 16" (2 x 8), which makes a circle with a
>> diameter of just under 5". (C = 2*pi*r = pi*d so d = C/pi).
>>
>> I think I need a rubber band with a diameter of about 8-9". That would
>> make it possible for me to stretch the band over the tire, but still
>> make it tight enough to stay on.
>>
>> If my geometry isn't too rusty, I will need a tube with an air chamber
>> that is between 13-14" wide when deflated and laid flat. A band cut
>> from such a tube would have a circumference of twice that (26-28") and
>> a diameter of 8-9".
>>
>> What size tube is that in standard tire designations?
>>
>> Any suggestions for where I should go to get a used or discarded tube?
>
>
>I generally dislike duct tape and its many wayward
>applications, but I think a few turns of it may do it in
>this case.

I don't care much for duct tape, either, and I think it would not be a
good choice here, but your suggestion got me thinking and I came up
with a couple of alternatives.

1. Rescue Tape. I'd never heard of this before. If it has any
thickness at all, it could be just the ticket.

http://www.rescuetape.com/

2. Rubber Bands. Several companies make custom rubber bands. Here are
a couple:

http://www.dykemarubberband.com/index.php
http://www.aerorubber.com/index.html

On Tue, 15 Feb 2011 00:24:17 +0000 (UTC), Brent
> wrote:

>On 2011-02-14, Prof Wonmug > wrote:
>> Can anyone tell me the formula for calculating the inside diameter of
>> the air chamber in an inner tube when inflated to just full (not
>> over-inflated as they do for river tubing).
>>
>> We recently replaced our asphalt driveway with pavers. It looks great,
>> but the trash bins now make an unholy racket when I roll them down the
>> driveway to the curb. I usually do this late at night or very early in
>> the morning, so the racket is annoying to us and to the neighbors.
>>
>> My solution is to cut rubber bands (3-4" wide) from an inner tube and
>> stretch them over the hard plastic wheels.
>>
>> I bought a Slime 5001-A inner tube from a local auto parts store that
>> is labeled "700/750 R15/16". I've seen these tubes inflated to several
>> times their normal size for tubing, so I figured it would work. I cut
>> one band from the tube and discovered that it only has a diameter of
>> about 5". I couldn't stretch it enough to get it onto the wheel.
>>
>> In retrospect, I should have inflated the tube as large as possible
>> and let it sit for a few days to stretch it out, but it's too late for
>> that now. I'm not even sure that would have worked. I could go buy
>> another tube and do that. Does anyone know how much I'd have to
>> inflate it and how I'd have to leave it to ghet it stretched out
>> enough?
>>
>> Does anyone have another suggestion for a way to stretch a very stiff
>> 5" rubber band to fit over a 10" wheel?
>>
>> If not, I need a larger inner tube. The question is, what size tube
>> should I look for?
>>
>> When the 700/750 R15/16 is deflated and laid flat, the tube rubber is
>> just under 8" wide. That is, the rubber band I cut from that tube is
>> just under 8" long. If formed into a circle, the circle has a
>> circumference of just under 16" (2 x 8), which makes a circle with a
>> diameter of just under 5". (C = 2*pi*r = pi*d so d = C/pi).
>
>> I think I need a rubber band with a diameter of about 8-9". That would
>> make it possible for me to stretch the band over the tire, but still
>> make it tight enough to stay on.
>>
>> If my geometry isn't too rusty, I will need a tube with an air chamber
>> that is between 13-14" wide when deflated and laid flat. A band cut
>> from such a tube would have a circumference of twice that (26-28") and
>> a diameter of 8-9".
>>
>> What size tube is that in standard tire designations?
>>
>> Any suggestions for where I should go to get a used or discarded tube?
>
>Harbor freight has a wide assortment of cheap wheels/tires that should
>work well...
>
>http://www.harborfreight.com/
>
>http://www.harborfreight.com/media/13.jpg

I looked into new tires. There are a couple of problems. If they are
inflated, then they will eventually lose air. They there is size. The
one you show for $4.99 looks too wide. It gives every other dimension.
The wheels of the cart are very narrow -- about 1.5" and very little
clearance. Then there's the axle size.

>That's probably less than you paid for the innertube.

I paid about $15 for the tube, but I'll get 15-20 bands from one tube,
which works out to about $1 each. ;-)

On 02/15/2011 03:21 AM, Prof Wonmug wrote:
> On Tue, 15 Feb 2011 00:24:17 +0000 (UTC), Brent
> > wrote:
>
>> On 2011-02-14, Prof > wrote:
>>> Can anyone tell me the formula for calculating the inside diameter of
>>> the air chamber in an inner tube when inflated to just full (not
>>> over-inflated as they do for river tubing).
>>>
>>> We recently replaced our asphalt driveway with pavers. It looks great,
>>> but the trash bins now make an unholy racket when I roll them down the
>>> driveway to the curb. I usually do this late at night or very early in
>>> the morning, so the racket is annoying to us and to the neighbors.
>>>
>>> My solution is to cut rubber bands (3-4" wide) from an inner tube and
>>> stretch them over the hard plastic wheels.
>>>
>>> I bought a Slime 5001-A inner tube from a local auto parts store that
>>> is labeled "700/750 R15/16". I've seen these tubes inflated to several
>>> times their normal size for tubing, so I figured it would work. I cut
>>> one band from the tube and discovered that it only has a diameter of
>>> about 5". I couldn't stretch it enough to get it onto the wheel.
>>>
>>> In retrospect, I should have inflated the tube as large as possible
>>> and let it sit for a few days to stretch it out, but it's too late for
>>> that now. I'm not even sure that would have worked. I could go buy
>>> another tube and do that. Does anyone know how much I'd have to
>>> inflate it and how I'd have to leave it to ghet it stretched out
>>> enough?
>>>
>>> Does anyone have another suggestion for a way to stretch a very stiff
>>> 5" rubber band to fit over a 10" wheel?
>>>
>>> If not, I need a larger inner tube. The question is, what size tube
>>> should I look for?
>>>
>>> When the 700/750 R15/16 is deflated and laid flat, the tube rubber is
>>> just under 8" wide. That is, the rubber band I cut from that tube is
>>> just under 8" long. If formed into a circle, the circle has a
>>> circumference of just under 16" (2 x 8), which makes a circle with a
>>> diameter of just under 5". (C = 2*pi*r = pi*d so d = C/pi).
>>
>>> I think I need a rubber band with a diameter of about 8-9". That would
>>> make it possible for me to stretch the band over the tire, but still
>>> make it tight enough to stay on.
>>>
>>> If my geometry isn't too rusty, I will need a tube with an air chamber
>>> that is between 13-14" wide when deflated and laid flat. A band cut
>>> from such a tube would have a circumference of twice that (26-28") and
>>> a diameter of 8-9".
>>>
>>> What size tube is that in standard tire designations?
>>>
>>> Any suggestions for where I should go to get a used or discarded tube?
>>
>> Harbor freight has a wide assortment of cheap wheels/tires that should
>> work well...
>>
>> http://www.harborfreight.com/
>>
>> http://www.harborfreight.com/media/13.jpg
>
> I looked into new tires. There are a couple of problems. If they are
> inflated, then they will eventually lose air. They there is size. The
> one you show for $4.99 looks too wide. It gives every other dimension.
> The wheels of the cart are very narrow -- about 1.5" and very little
> clearance. Then there's the axle size.
>
>> That's probably less than you paid for the innertube.
>
> I paid about $15 for the tube, but I'll get 15-20 bands from one tube,
> which works out to about $1 each. ;-)

why not just cut strips from the tube you already have and glue them
onto the wheels? make 'em too long, overlap the ends, then make one
slice with a razor blade and remove the little pieces. et voila.
Doesn't cost you a thing, unless you need to buy glue. I'd probably try
either contact cement, or automotive trim cement (the 3M yellow snot
stuff,) whichever you have handy.

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

On Tue, 15 Feb 2011 20:04:11 -0500, Nate Nagel >
wrote:

>On 02/15/2011 03:21 AM, Prof Wonmug wrote:
>> On Tue, 15 Feb 2011 00:24:17 +0000 (UTC), Brent
>> > wrote:
>>
>>> On 2011-02-14, Prof > wrote:
>>>> Can anyone tell me the formula for calculating the inside diameter of
>>>> the air chamber in an inner tube when inflated to just full (not
>>>> over-inflated as they do for river tubing).
>>>>
>>>> We recently replaced our asphalt driveway with pavers. It looks great,
>>>> but the trash bins now make an unholy racket when I roll them down the
>>>> driveway to the curb. I usually do this late at night or very early in
>>>> the morning, so the racket is annoying to us and to the neighbors.
>>>>
>>>> My solution is to cut rubber bands (3-4" wide) from an inner tube and
>>>> stretch them over the hard plastic wheels.
>>>>
>>>> I bought a Slime 5001-A inner tube from a local auto parts store that
>>>> is labeled "700/750 R15/16". I've seen these tubes inflated to several
>>>> times their normal size for tubing, so I figured it would work. I cut
>>>> one band from the tube and discovered that it only has a diameter of
>>>> about 5". I couldn't stretch it enough to get it onto the wheel.
>>>>
>>>> In retrospect, I should have inflated the tube as large as possible
>>>> and let it sit for a few days to stretch it out, but it's too late for
>>>> that now. I'm not even sure that would have worked. I could go buy
>>>> another tube and do that. Does anyone know how much I'd have to
>>>> inflate it and how I'd have to leave it to ghet it stretched out
>>>> enough?
>>>>
>>>> Does anyone have another suggestion for a way to stretch a very stiff
>>>> 5" rubber band to fit over a 10" wheel?
>>>>
>>>> If not, I need a larger inner tube. The question is, what size tube
>>>> should I look for?
>>>>
>>>> When the 700/750 R15/16 is deflated and laid flat, the tube rubber is
>>>> just under 8" wide. That is, the rubber band I cut from that tube is
>>>> just under 8" long. If formed into a circle, the circle has a
>>>> circumference of just under 16" (2 x 8), which makes a circle with a
>>>> diameter of just under 5". (C = 2*pi*r = pi*d so d = C/pi).
>>>
>>>> I think I need a rubber band with a diameter of about 8-9". That would
>>>> make it possible for me to stretch the band over the tire, but still
>>>> make it tight enough to stay on.
>>>>
>>>> If my geometry isn't too rusty, I will need a tube with an air chamber
>>>> that is between 13-14" wide when deflated and laid flat. A band cut
>>>> from such a tube would have a circumference of twice that (26-28") and
>>>> a diameter of 8-9".
>>>>
>>>> What size tube is that in standard tire designations?
>>>>
>>>> Any suggestions for where I should go to get a used or discarded tube?
>>>
>>> Harbor freight has a wide assortment of cheap wheels/tires that should
>>> work well...
>>>
>>> http://www.harborfreight.com/
>>>
>>> http://www.harborfreight.com/media/13.jpg
>>
>> I looked into new tires. There are a couple of problems. If they are
>> inflated, then they will eventually lose air. They there is size. The
>> one you show for $4.99 looks too wide. It gives every other dimension.
>> The wheels of the cart are very narrow -- about 1.5" and very little
>> clearance. Then there's the axle size.
>>
>>> That's probably less than you paid for the innertube.
>>
>> I paid about $15 for the tube, but I'll get 15-20 bands from one tube,
>> which works out to about $1 each. ;-)
>
>why not just cut strips from the tube you already have and glue them
>onto the wheels? make 'em too long, overlap the ends, then make one
>slice with a razor blade and remove the little pieces. et voila.
>Doesn't cost you a thing, unless you need to buy glue. I'd probably try
>either contact cement, or automotive trim cement (the 3M yellow snot
>stuff,) whichever you have handy.

I was a little reluctant to use glue in case I ever needed to
remove/replace them, but maybe you have a point. I've never used the
trim cement. Is this it?

http://tinyurl.com/4qpz4zp