Date   
Re: Interesting discussion on gas diffusion in rubber

Medad rufus
 

interesting

On Thu, 6 Aug 2020 at 10:37, steve@... via groups.io <steve=btinternet.com@groups.io> wrote:
https://www.youtube.com/watch?v=yNmmX83xIGM&t=3m16s

not what I expected.

Interesting discussion on gas diffusion in rubber

steve@btinternet.com
 

Re: Hydrogen regulators?

Carlton Corbitt
 

Hi Hank,

The regulator doesn't seem to regulate, it is about 30psi out.

Turning the knob on the front makes it open or close/stop the flow of Hydrogen. 

Maybe it never adjusted, it just seemed right pressure and i accepted it.   It does make it a little be odd to fill balloons to a precise lift.  I have to use the valve on the tank itself to control anything.
The Smith regulator only does a fixed pressure step down.  No control on the regulator except open(~30psi) or closed (0psi).

For near space ballooning it gets the job done, and for only $45.  But a regulator that doesn't adjust regulation pressure does kind of freak some people out.

Carlton
KI4NHK

Re: Hydrogen regulators?

Barry
 

No need to spend more than about $100. Some regulators have to be built using special materials (like those for corrosive gases), but hydrogen and oxygen regulators are built the same and I have purchased 4 or 5 oxygen regulators from a local regulator repair shop over the years for several teachers and others needing a hydrogen regulator for filling balloons for less than $100 each with the oxygen tank fitting replaced by the repair shop with one for a hydrogen tank. The regulators are like the ones typically seen used for welding with 2 gauges and, with them costing a bit more than $90 in Canada, you should be able to find one for even less in the US without much trouble.

 

Acetylene and oxygen regulators are much more popular and therefore less expensive than regulators for other gases plus regulators for other gases are usually laboratory grade (more precise) thus much more expensive. Regulators for other gases (other than oxygen) could probably be used as well by changing the tank fitting but you can’t beat the low cost of a new oxygen regulator plus some regulators are designed to provide a low flow rate rather than a high flow rate like an oxygen regulator does. Final point – It’s probably not a good idea (and not recommended) to modify a previously used regulator (especially an oxygen regulator) as the internal parts can out gas the previously used gas which could lead to a problem so best to start with a brand new regulator.

 

Barry
VE6SBS

 

From: GPSL@groups.io [mailto:GPSL@groups.io] On Behalf Of Larry
Sent: Wednesday, July 29, 2020 3:47 PM
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?

Hank Riley
 

Carlton,

That's exactly the model Larry is looking at!  It's listed by Smith as a single stage by the way with a 3 year limited warranty.  Not likely you could find a two stage regulator, new, through a distributor, for that kind of low price ($93.50 from Cyberweld via Amazon).

Could you please describe in a little more detail how the regulator misbehaves?  Once set at a usable outlet pressure does it hold that pressure throughout the fill?

Hank
____________________

On Thursday, July 30, 2020, 10:50:09 AM EDT, Carlton  wrote:

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.

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@...