Date   

Re: Hydrogen regulators?

Carlton Corbitt
 

One regulator to avoid might be 

Smith 30-100-350

It is a 2 stage regulator I bought off Ebay a number of years ago probably 2013-2014.  I think i paid $45 + shipping for this regulator brand New in packaging.
It has less than a dozen flights but gives frustration adjusting.

I still consider it usable but with cation.   The first year (maybe 2 or 3 flights) no issues.  After warranty ended started having issues.

73,
Carlton Corbitt
KI4NHK




Helium to hydrogen thread adapter / was Re: [GPSL] Helium Supply (in 2018)

Hank Riley
 

Larry,

On Amazon now it's $26.94.  You can go lower than that on ebay right now.  


Hank
__________________________________________________________________


On Wednesday, April 18, 2018,  Bill Brown wrote:

You will need a CGA-580 to CGA-350 adaptor to use a helium regulator with a hydrogen tank but the adapter can be bought on Amazon for around $15. Also, don't crack open a hydrogen tank unless there is a regulator on it.


Re: Hydrogen regulators?

Graham
 

hydrogen cylinders and regulators use a CGA-350 connector.



A search using your favourite search engine will find many more references.

As long as the regulator has the correct inlet PSI rating  ( ie 3000 psi ) and has the correct connector  ( i.e. CGA-350 ) then all should be good.

The regulator at the link provided noted  a max inlet pressure of 3000 psi, a cga-350 connection and a 9/16"-18 LH outlet connector as I would expect as it is being sold as a hydrogen regulator.

cheers, Graham ve3gtc




On Wed, Jul 29, 2020 at 10:25 PM Joe WB9SBD <nss@...> wrote:
They key is for H2 is left hand thread. AND even for safety the pressure it can take. that one looks good in both cases.

NOW the one we have been using 30+ years of flights, been using H2 from first flight every flight.

But ours was not specified for H@, but some other Gas.

the thing is tho the left thread and the pressure capability.

The NOT spec'ed H2 was given to us, so cost?

Joe WB9SBD

The Original Rolling Ball Clock
Idle Tyme
Idle-Tyme.com
http://www.idle-tyme.com

On 7/29/2020 4:56 PM, L. Paul Verhage KD4STH wrote:
This one looks adjustable. I spent far less at my local welding shop for a regulator with fixed settings.

Are you asking for an adjustable regulator? I think mine is permanently set for 30 PSI exit (outlet?) pressure.

On Wed, Jul 29, 2020, 3:47 PM Larry <larry.phegley@...> wrote:
I keep having to ask you questions.  Well I appreciate your help anyway.  So we are  trying to shift over to hydrogen and the local welding supply place wants $500 for a regulator.  Yet I see this $93 dollar regulator on line.  


Why should I not spend $93 instead of $500?

Larry
 


Re: Hydrogen regulators?

Hank Riley
 

On this list right hand to left hand adapters have been discussed and bought by several groups.  There were even part numbers specified, IIRC.  That way their tried-and-true helium regulators didn't go to waste when a lot of the groups switched to hydrogen.

Not too much money for those.  Look on Ebay.  All over the place.


Re: Hydrogen regulators?

Hank Riley
 

That $500 price is totally nutz!!!!  I can't imagine what device they have in mind.  Just for grins you might ask them for a catalog sheet, or a make and model number.

You can easily beat that $93 price by watching Ebay for regulators.  I got a fancy two stage regulator made by Linde (no better brand) years ago on Ebay -- it's a real gem (something like $20 shipped!).  Nice big gauges -- not midgets.

One stage regulation is enough, though.  One or two stage makes a fairly big price difference if bought new.  It is nice to have it variable.  Fixed output is a little cheesy, especially for small balloons.
________________________________________________________________________________________


On Wed, Jul 29, 2020, 3:47 PM Larry wrote:
I keep having to ask you questions.  Well I appreciate your help anyway.  So we are  trying to shift over to hydrogen and the local welding supply place wants $500 for a regulator.  Yet I see this $93 dollar regulator on line.  


Re: Hydrogen regulators?

Bruce Coates
 

Yes, mine is adjustable.  You definitely want that for pico balloons or a flow restrict or because they take so little gas.


-------- Original message --------
From: "L. Paul Verhage KD4STH" <nearsys@...>
Date: 7/29/20 3:56 PM (GMT-06:00)
To: GPSL@groups.io
Subject: Re: [GPSL] Hydrogen regulators?

This one looks adjustable. I spent far less at my local welding shop for a regulator with fixed settings.

Are you asking for an adjustable regulator? I think mine is permanently set for 30 PSI exit (outlet?) pressure.

On Wed, Jul 29, 2020, 3:47 PM Larry <larry.phegley@...> wrote:
I keep having to ask you questions.  Well I appreciate your help anyway.  So we are  trying to shift over to hydrogen and the local welding supply place wants $500 for a regulator.  Yet I see this $93 dollar regulator on line.  


Why should I not spend $93 instead of $500?

Larry
 


Re: Hydrogen regulators?

Bruce Coates
 

I'm no expert on regulators so I'm hesitant to give an opinion.  If you can find reputable reviews for this brand, it should be just fine.  Mine is a well known brand thst I bought on ebay that wasn't too expensive because it was used.  I've also heard of people using a helium regulator with a fitting adaptor sot it thread into the hydrogen fitting.  Here to I wouldn't want to be the guy to endorse that.

 Rucs


-------- Original message --------
From: Larry <larry.phegley@...>
Date: 7/29/20 3:47 PM (GMT-06:00)
To: gpsl@groups.io
Subject: [GPSL] Hydrogen regulators?

I keep having to ask you questions.  Well I appreciate your help anyway.  So we are  trying to shift over to hydrogen and the local welding supply place wants $500 for a regulator.  Yet I see this $93 dollar regulator on line.  


Why should I not spend $93 instead of $500?

Larry
 


Re: Hydrogen regulators?

Joe WB9SBD
 

They key is for H2 is left hand thread. AND even for safety the pressure it can take. that one looks good in both cases.

NOW the one we have been using 30+ years of flights, been using H2 from first flight every flight.

But ours was not specified for H@, but some other Gas.

the thing is tho the left thread and the pressure capability.

The NOT spec'ed H2 was given to us, so cost?

Joe WB9SBD

The Original Rolling Ball Clock
Idle Tyme
Idle-Tyme.com
http://www.idle-tyme.com

On 7/29/2020 4:56 PM, L. Paul Verhage KD4STH wrote:
This one looks adjustable. I spent far less at my local welding shop for a regulator with fixed settings.

Are you asking for an adjustable regulator? I think mine is permanently set for 30 PSI exit (outlet?) pressure.

On Wed, Jul 29, 2020, 3:47 PM Larry <larry.phegley@...> wrote:
I keep having to ask you questions.  Well I appreciate your help anyway.  So we are  trying to shift over to hydrogen and the local welding supply place wants $500 for a regulator.  Yet I see this $93 dollar regulator on line.  


Why should I not spend $93 instead of $500?

Larry
 


Re: Hydrogen regulators?

L. Paul Verhage KD4STH
 

This one looks adjustable. I spent far less at my local welding shop for a regulator with fixed settings.

Are you asking for an adjustable regulator? I think mine is permanently set for 30 PSI exit (outlet?) pressure.

On Wed, Jul 29, 2020, 3:47 PM Larry <larry.phegley@...> wrote:
I keep having to ask you questions.  Well I appreciate your help anyway.  So we are  trying to shift over to hydrogen and the local welding supply place wants $500 for a regulator.  Yet I see this $93 dollar regulator on line.  


Why should I not spend $93 instead of $500?

Larry
 


Hydrogen regulators?

Larry
 

I keep having to ask you questions.  Well I appreciate your help anyway.  So we are  trying to shift over to hydrogen and the local welding supply place wants $500 for a regulator.  Yet I see this $93 dollar regulator on line.  


Why should I not spend $93 instead of $500?

Larry
 


Re: Streaming video from a balloon

Nick Pugh K5QXJ
 

Yes which video you may also want to call

 

 

 

 

 

 

 

nick

 

Cell      337 258 2527

 

Helping UL become a world Class Engineering  and Educational School

Disagree I Learn

 

 

From: GPSL@groups.io <GPSL@groups.io> On Behalf Of Larry
Sent: Tuesday, July 28, 2020 6:14 PM
To: gpsl@groups.io
Subject: [GPSL] Streaming video from a balloon

 

Mike ...  Could I ask you  some questions off line about how you streamed the video?

 

Larry

KJ6PBS

 


Streaming video from a balloon

Larry
 

Mike ...  Could I ask you  some questions off line about how you streamed the video?

Larry
KJ6PBS


Re: Helium in a tank?

Jayant Murthy
 

Hydrogen is the way to go. Avoid closed spaces and sparks!
Jayant

On Thursday, July 23, 2020, 11:30:40 PM GMT+5:30, Larry <larry.phegley@...> wrote:


I called and he assured me it was pure helium.  ???  I can't see another explanation why it didn't lift.  Anyway after checking the cost of gas and the cost of conversion ....  Hydrogen here we come

Larry


On Mon, Jul 20, 2020 at 8:39 PM steve potter <spotterotter@...> wrote:
I ran into that with a tank from oxarc, entire s cyl and it didn't lift off the ground and by the calculations we did the s cyl should of been a couple of extra cubic feet. It was great that a fellow ham invited lived about a quarter mile away from the launch site and had a tank at his house. He's not even into balloons but apparently we are all a bit different than the rest of the world.

On Mon, Jul 20, 2020, 11:40 AM K. Mark Caviezel via groups.io <kmcaviezel=yahoo.com@groups.io> wrote:
Caution:
I have encountered at least two industrial gas suppliers that offer lower cost 'balloon grade helium' which is not 99% or better helium.(!)  It is 30%-40% nitrogen.  The thought and rationale is that for normal party balloons, the inclusion of lower cost nitrogen allows persons to fully inflate party balloons, they'll float just fine and a bit cheaper than going with pure helium.  And this will very seriously screw up lift and burst calculations if you use it in a high altitude balloon. I've never used it.  But both times it was offered to me it took a surprising amount of dialog with the industrial gas guys to suss out that it is a 60-40 or 70-30% mix of helium and nitrogen. I don't necessarily fault the guys working at the industrial gas suppliers, they've undoubtedly been briefed that their balloon grade helium is the best stuff for filling balloons.  For 99+% of their customers that are filling balloons it probably is.


Re: Helium in a tank?

Larry
 

I called and he assured me it was pure helium.  ???  I can't see another explanation why it didn't lift.  Anyway after checking the cost of gas and the cost of conversion ....  Hydrogen here we come

Larry


On Mon, Jul 20, 2020 at 8:39 PM steve potter <spotterotter@...> wrote:
I ran into that with a tank from oxarc, entire s cyl and it didn't lift off the ground and by the calculations we did the s cyl should of been a couple of extra cubic feet. It was great that a fellow ham invited lived about a quarter mile away from the launch site and had a tank at his house. He's not even into balloons but apparently we are all a bit different than the rest of the world.

On Mon, Jul 20, 2020, 11:40 AM K. Mark Caviezel via groups.io <kmcaviezel=yahoo.com@groups.io> wrote:
Caution:
I have encountered at least two industrial gas suppliers that offer lower cost 'balloon grade helium' which is not 99% or better helium.(!)  It is 30%-40% nitrogen.  The thought and rationale is that for normal party balloons, the inclusion of lower cost nitrogen allows persons to fully inflate party balloons, they'll float just fine and a bit cheaper than going with pure helium.  And this will very seriously screw up lift and burst calculations if you use it in a high altitude balloon. I've never used it.  But both times it was offered to me it took a surprising amount of dialog with the industrial gas guys to suss out that it is a 60-40 or 70-30% mix of helium and nitrogen. I don't necessarily fault the guys working at the industrial gas suppliers, they've undoubtedly been briefed that their balloon grade helium is the best stuff for filling balloons.  For 99+% of their customers that are filling balloons it probably is.


Re: Superpressure balloon valve / was Re: [GPSL] K5NOT-11 WSPR Balloon Failure

Bill Brown
 

I managed to float a couple of 1200 and 1500 gram balloons by putting a PVC pipe with an end cap in the neck of the balloon and drilling a 1/16" hole in the end cap (two 1/16" holes were too much as were larger size drill holes). The ones with the single 1/16" hole all floated all night long over 100,000 feet or so. 

- Bill WB8ELK


-----Original Message-----
From: BASE_DePauw <hlbrooks@...>
To: GPSL@groups.io
Sent: Tue, Jul 21, 2020 9:27 pm
Subject: Re: Superpressure balloon valve / was  Re: [GPSL] K5NOT-11 WSPR Balloon Failure

I suggest reaching out to Michael K5NOT (ARBONET) who did the presentation at GPSL 2010.

Another investigator was James Flaten with his students at the University of Minnesota who shared their results at the Academic High Altitude Conference that same summer at Taylor University.

I cannot find copies of either presentation in my files tonight.

Howard, KC9QBN
BASE_DePauw



On Tue, Jul 21, 2020 at 10:12 PM Mark Conner N9XTN <mconner1@...> wrote:
I searched my Gmail archive and there are fragments of a discussion on this topic based on an ARBONET balloon flight in the summer of 2010 which may have measured this.  There may even have been a GPSL presentation that summer on it.  If you look in the archived messages from ~June-Sept 2010 you may find something.

GPSL 2010 was in Hutchinson KS.

73 de Mark N9XTN

On Tue, Jul 21, 2020 at 7:40 PM Dennis Klipa - N8ERF <klipadk@...> wrote:
I am curious.  Many of us have measured the atmospheric pressure versus altitude.  I have wanted to, but haven't, measured the pressure inside the latex balloon as it rises.  Has anyone measured the pressure differential (inside vs outside) of the latex balloon as a function of altitude?  How much difference are we talking about trying to control with this valve.  If the balloon were a fixed volume you could do the calculation, but the latex balloons are not.

Best Regards,
Dennis Klipa, N8ERF



--
Howard L. Brooks
Professor of Physics and Astronomy
241 Julian Science and Mathematics Center
DePauw University
2 E. Hanna Street
Greencastle, IN 46135
hlbrooks@...


Re: Superpressure balloon valve / was Re: [GPSL] K5NOT-11 WSPR Balloon Failure

BASE_DePauw
 

I suggest reaching out to Michael K5NOT (ARBONET) who did the presentation at GPSL 2010.

Another investigator was James Flaten with his students at the University of Minnesota who shared their results at the Academic High Altitude Conference that same summer at Taylor University.

I cannot find copies of either presentation in my files tonight.

Howard, KC9QBN
BASE_DePauw



On Tue, Jul 21, 2020 at 10:12 PM Mark Conner N9XTN <mconner1@...> wrote:
I searched my Gmail archive and there are fragments of a discussion on this topic based on an ARBONET balloon flight in the summer of 2010 which may have measured this.  There may even have been a GPSL presentation that summer on it.  If you look in the archived messages from ~June-Sept 2010 you may find something.

GPSL 2010 was in Hutchinson KS.

73 de Mark N9XTN

On Tue, Jul 21, 2020 at 7:40 PM Dennis Klipa - N8ERF <klipadk@...> wrote:
I am curious.  Many of us have measured the atmospheric pressure versus altitude.  I have wanted to, but haven't, measured the pressure inside the latex balloon as it rises.  Has anyone measured the pressure differential (inside vs outside) of the latex balloon as a function of altitude?  How much difference are we talking about trying to control with this valve.  If the balloon were a fixed volume you could do the calculation, but the latex balloons are not.

Best Regards,
Dennis Klipa, N8ERF




--
Howard L. Brooks
Professor of Physics and Astronomy
241 Julian Science and Mathematics Center
DePauw University
2 E. Hanna Street
Greencastle, IN 46135
hlbrooks@...


Re: Superpressure balloon valve / was Re: [GPSL] K5NOT-11 WSPR Balloon Failure

Mark Conner N9XTN
 

I searched my Gmail archive and there are fragments of a discussion on this topic based on an ARBONET balloon flight in the summer of 2010 which may have measured this.  There may even have been a GPSL presentation that summer on it.  If you look in the archived messages from ~June-Sept 2010 you may find something.

GPSL 2010 was in Hutchinson KS.

73 de Mark N9XTN

On Tue, Jul 21, 2020 at 7:40 PM Dennis Klipa - N8ERF <klipadk@...> wrote:
I am curious.  Many of us have measured the atmospheric pressure versus altitude.  I have wanted to, but haven't, measured the pressure inside the latex balloon as it rises.  Has anyone measured the pressure differential (inside vs outside) of the latex balloon as a function of altitude?  How much difference are we talking about trying to control with this valve.  If the balloon were a fixed volume you could do the calculation, but the latex balloons are not.

Best Regards,
Dennis Klipa, N8ERF



Re: Superpressure balloon valve / was Re: [GPSL] K5NOT-11 WSPR Balloon Failure

Dennis Klipa - N8ERF
 

Thanks for looking.  I assume the data was consistent with the data you shared.

Dennis

On Tue, Jul 21, 2020, 9:33 PM Jerry via groups.io <jerrygable=yahoo.com@groups.io> wrote:
Correct.  I also did a test during a flight but couldn't find the data.

Jerry


On Tue, Jul 21, 2020 at 6:31 PM, Dennis Klipa - N8ERF
<klipadk@...> wrote:
Jerry,

Thanks for the data.  Pretty small differential.  I assume that the graph shows the differential pressure vs time during which you added gas to the balloon at a more or less constant rate.  Is that correct?

Best Regards,
Dennis, N8ERF

On Tue, Jul 21, 2020, 9:19 PM Jerry via groups.io <jerrygable=yahoo.com@groups.io> wrote:
I did some experiments on the differential pressure on a balloon  This was a ground test on a fairly small latex balloon (100 Grams I believe)  but larger ones would be similar.  As you approach burst the diff. pressure rises. 

A good analogy is a rubber band.  There is a high force for the initial stretch of a new band then it drops off.  The pressure increases as you reach the breaking point.

The pressure doesn't change much on a balloon so you have to be pretty accurate if you want to obtain float wit a latex balloon.  It has been done with a very low amount of lift gas.

I suspect a Mylar balloon would have a sharper curve since they don't stretch but I haven't done any burst experiments with those.


Inline image


Jerry Gable
Balloon Flight Prediction tools
http://www.s3research.com


On Tuesday, July 21, 2020, 6:05:54 PM MST, Joe WB9SBD <nss@...> wrote:


I did have these numbers, But it was a long time ago.

The numbers I got I did it by testing a piece of the envelope it's tensile strength, and doing the tons of math to learn what the pressure differential would be.

What was interesting was someone ( do not remember who) actually did flight(s) with a pressure sensor.
The neat part was my measured of material and the math calculations, the number I got was within like 5% of what they measured.

Joe WB9SBD

On 7/21/2020 7:39 PM, Dennis Klipa - N8ERF wrote:
I am curious.  Many of us have measured the atmospheric pressure versus altitude.  I have wanted to, but haven't, measured the pressure inside the latex balloon as it rises.  Has anyone measured the pressure differential (inside vs outside) of the latex balloon as a function of altitude?  How much difference are we talking about trying to control with this valve.  If the balloon were a fixed volume you could do the calculation, but the latex balloons are not.

Best Regards,
Dennis Klipa, N8ERF

On Tue, Jul 21, 2020, 8:23 PM Joe WB9SBD <nss@...> wrote:
It was a 1500 Kaymont balloon.

Knowing the pressure differential is extremely low. When I tested the ping pong ball, I know it leaked badly. The texture of the ball just would not give a good seal.

I went with the silicone on both the "O" ring and the ball.

I also went with a pressure of the spring, Actually a spring I just could not find a spring suitable.  So I used a left over strip of balloon latex, attached to the ball and to a acrylic shaft.

The shaft was rotated to tighten the tension on the ball and seal.

I made it as loose as possible,, just enough to make the seal, and I mean barely!

I was worried that motion would even break the seal. It was that slight.

Even as light as that was,  it was not light enough, the flight still had a standard flight profile with rise to burst altitude, and did still pop.

Joe WB9SBD

On 7/21/2020 3:41 PM, Hank Riley via groups.io wrote:
Joe, please tell us more.  

Latex or other envelope?  How did it work out for you?  Any special reason for trying this valve method out?  What altitude was reached?   How long did it remain in the air?
___________________________________________________________


On Sunday, July 19, 2020, 09:06:33 AM EDT, Joe wrote:

I did that once. But the ping pong ball surface is too textured and does not make a bubble tight seal. I did a silicone ball and o ring.




Re: Superpressure balloon valve / was Re: [GPSL] K5NOT-11 WSPR Balloon Failure

Joe WB9SBD
 

I remember the data that matched mine, was the actual flying flight.

There was a small but very detectable spike just before burst.

And when I did the tensile strength test it was the same way almost a slight and linear higher force, but right at the end, this small spike.

Take a piece of balloon leftovers. start to stretch it, it is pretty smooth as you stretch it, but suddenly the resistance to stretch any further jumps greatly!

Joe WB9SBD

On 7/21/2020 8:33 PM, Jerry via groups.io wrote:
Correct.  I also did a test during a flight but couldn't find the data.

Jerry


On Tue, Jul 21, 2020 at 6:31 PM, Dennis Klipa - N8ERF
Jerry,

Thanks for the data.  Pretty small differential.  I assume that the graph shows the differential pressure vs time during which you added gas to the balloon at a more or less constant rate.  Is that correct?

Best Regards,
Dennis, N8ERF

On Tue, Jul 21, 2020, 9:19 PM Jerry via groups.io <jerrygable=yahoo.com@groups.io> wrote:
I did some experiments on the differential pressure on a balloon  This was a ground test on a fairly small latex balloon (100 Grams I believe)  but larger ones would be similar.  As you approach burst the diff. pressure rises. 

A good analogy is a rubber band.  There is a high force for the initial stretch of a new band then it drops off.  The pressure increases as you reach the breaking point.

The pressure doesn't change much on a balloon so you have to be pretty accurate if you want to obtain float wit a latex balloon.  It has been done with a very low amount of lift gas.

I suspect a Mylar balloon would have a sharper curve since they don't stretch but I haven't done any burst experiments with those.


Inline image


Jerry Gable
Balloon Flight Prediction tools
http://www.s3research.com


On Tuesday, July 21, 2020, 6:05:54 PM MST, Joe WB9SBD <nss@...> wrote:


I did have these numbers, But it was a long time ago.

The numbers I got I did it by testing a piece of the envelope it's tensile strength, and doing the tons of math to learn what the pressure differential would be.

What was interesting was someone ( do not remember who) actually did flight(s) with a pressure sensor.
The neat part was my measured of material and the math calculations, the number I got was within like 5% of what they measured.

Joe WB9SBD

On 7/21/2020 7:39 PM, Dennis Klipa - N8ERF wrote:
I am curious.  Many of us have measured the atmospheric pressure versus altitude.  I have wanted to, but haven't, measured the pressure inside the latex balloon as it rises.  Has anyone measured the pressure differential (inside vs outside) of the latex balloon as a function of altitude?  How much difference are we talking about trying to control with this valve.  If the balloon were a fixed volume you could do the calculation, but the latex balloons are not.

Best Regards,
Dennis Klipa, N8ERF

On Tue, Jul 21, 2020, 8:23 PM Joe WB9SBD <nss@...> wrote:
It was a 1500 Kaymont balloon.

Knowing the pressure differential is extremely low. When I tested the ping pong ball, I know it leaked badly. The texture of the ball just would not give a good seal.

I went with the silicone on both the "O" ring and the ball.

I also went with a pressure of the spring, Actually a spring I just could not find a spring suitable.  So I used a left over strip of balloon latex, attached to the ball and to a acrylic shaft.

The shaft was rotated to tighten the tension on the ball and seal.

I made it as loose as possible,, just enough to make the seal, and I mean barely!

I was worried that motion would even break the seal. It was that slight.

Even as light as that was,  it was not light enough, the flight still had a standard flight profile with rise to burst altitude, and did still pop.

Joe WB9SBD

On 7/21/2020 3:41 PM, Hank Riley via groups.io wrote:
Joe, please tell us more.  

Latex or other envelope?  How did it work out for you?  Any special reason for trying this valve method out?  What altitude was reached?   How long did it remain in the air?
___________________________________________________________


On Sunday, July 19, 2020, 09:06:33 AM EDT, Joe wrote:

I did that once. But the ping pong ball surface is too textured and does not make a bubble tight seal. I did a silicone ball and o ring.





Re: Superpressure balloon valve / was Re: [GPSL] K5NOT-11 WSPR Balloon Failure

Jerry
 

The x axis is time.  It was just a relatively constant fill rate.


On Tue, Jul 21, 2020 at 6:35 PM, Hank Riley via groups.io
<n1ltv@...> wrote:
Jerry, what do the numbers along the x-axis mean?




On Tuesday, July 21, 2020, 09:19:54 PM EDT, Jerry wrote:

I did some experiments on the differential pressure on a balloon  This was a ground test on a fairly small latex balloon (100 Grams I believe)  but larger ones would be similar. 

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