Spreading the knowledge

[Gerryd]

Hi all,

Just want to let you all know that thanks to the knowledge I have learned about high quality regulators and components that I am posting a build/knowledge thread for my clone build on the FAPS site I posted about the other day.

Just want to thank Leftc and Matt F especially for all of their effort and responsiveness without which I would still be ignorant of c02 equipment.

Many others have assisted, too many to thank, Tom comes to mind though for his liberal posting rules and views...

I hope to at least eliminate some of the mysteries around what is needed and why.

I only know a little bit, but that already makes a huge difference in how I evaluate the quality of retail rigs online....

 

[Tom Barr]

Matt and I talked the other day about LeftC's post being removed on other sites.
I do not understand why. So I said come here.

There's some trade offs and problems with Dual vs single stage, the biggest is really finding a cheaper new product solution that meets the aquarist needs.
At 250-300$, vs say 50-100$, this is huge leap. A cheaper (eg Chinese) knock off is needed that is high grade, but 1/2 the cost.
Then a retail company that can make and sell one to the Reef and Plant folks.

That is really what is needed.
Arguing for a $$ item is not going to go well otherwise.

 

[Tom Barr]

My discussion was promoted by some concerns at Aqua Forest Aquarium.
George asked me a question about CO2.

Some had come in looking for a dual stage reg, but he mentioned they had good experiences with the single stage higher grade with nice valves. They where not impressed and would not buy one, instead, thinking the store should perhaps sell dual stage.

I think single stage do work fine, but you need a good one and good valve to accompany them. I'd like to see a decent dual stage offered at AFA, but 300$ or more for something new is not going to cut it. Sure, you can DIY a used one, put the parts together, which is not always easy, nor locating the parts etc. No store is going to do that obviously. While I agree and love the Dual design and the trade offs suit our hobby very very well.........there's some issues I think on the merchant end of things. I do not think it's fair really.

Some CO2 equipment and designs are truly junk and cause problems, but others are not as bad and just fine for long term use. Since ADA prides itself on being the best and no expense spared type of company, it would seem that a dual stage would be offered.

Dual stages are clearly a better design, but that pesky cost difference......(I'm not talking DIY).

 

[Jim Miller]

I don't know how a valve (presumably needle) can deal with the rise in pressure that is inevitable with single stage regulators. The basic design of the single stage regulator requires that a combination of outlet chamber pressure and spring pressure hold the orifice open against the tank pressure. If the tank pressure gets too low the outlet chamber pressure combined with the spring win the battle and the tank exhausts.

A dual stage regulator is two single stages in series and when the first high pressure stage begins reacting to the end-of-tank pressure drop, its outlet side pressure increases which causes the second stage to see a higher, rather than lower pressure, for much of the end-of-tank period. Thus limiting the "dump period" the needle valve sees.

The only thing a needle valve might do is freeze up due to adiabatic expansion if the pressure and consequent flow rate goes high enough. I'm not sure that relying on that is a good idea. Otherwise higher pressure means higher flow rate through the needle valve regardless of its price.

What am I missing?

Jim

 

[Jim Miller]

I agree that most folks aren't likely to buy a new $500 (or more) dual stage regulator and most will not DIY with a used regulator from Ebay. It seems that the supply on Ebay is inexhaustable but I continue to wonder why. I think it's likely that the regulators found there either have started to fail in their primary use, the business failed and all their equipment was liquidated or there is a "don't use after date" on the equipment for some scientific or medical reason.

The flow rates on the typical industrial regulator are enormous compared to our needs. The argon and some CO2 units are used to flood TIG/MIG welding sites. We want a controllable leak by comparison. There is a company which makes a composite unit that might be a step in the right direction: http://www.genuineinnovations.com/composite-regulator.html

I've not spoken to them.

Jim

 

[Jim Miller]

Some numbers: assume a 10lb CO2 cylinder is connected somehow to the tank, produces the desired CO2 concentration and lasts 6 months. That's 160oz/180 days or a bit less than 1oz/day. Taking it down to the second where folks like to count bubbles and assuming that emission only occurs for 8hrs (28,800 seconds) that's 35microounces per second or about 1mg/sec. Not a lot of mass flow.

My comment earlier about adiabatically limiting mass flow was perhaps too quick. I suppose it would be possible to do a needle and orifice of different coefficients of expansion of a small enough total mass to permit closure of the opening when the flowrate increased thus dropping the temperature of the assembly and reducing flow by design. I was reminded of that by my propane gas grill's single stage regulator that wouldn't function near freezing and I had to get a two stage regulator to avoid the choking on the ambient plus adiabatic temperature drop suffered by the single stage.

As to the composite regulator it could likely be used as a inexpensive second stage preset to 32psi with a conventional metal single stage regulator preset to 100psi preceding it. Removing adjustments by doing presets would reduce complexity which would make CO2 more user friendly to a wider audience.

I think that people think they're saving significant $$ by letting the tank drop to zero before filling it. IIRC once the tank gets to 400psi there's less than 5% by mass remaining. A bit silly...

jim

 

[hbosman]

Some numbers: assume a 10lb CO2 cylinder is connected somehow to the tank, produces the desired CO2 concentration and lasts 6 months. That's 160oz/180 days or a bit less than 1oz/day. Taking it down to the second where folks like to count bubbles and assuming that emission only occurs for 8hrs (28,800 seconds) that's 35microounces per second or about 1mg/sec. Not a lot of mass flow.

My comment earlier about adiabatically limiting mass flow was perhaps too quick. I suppose it would be possible to do a needle and orifice of different coefficients of expansion of a small enough total mass to permit closure of the opening when the flowrate increased thus dropping the temperature of the assembly and reducing flow by design. I was reminded of that by my propane gas grill's single stage regulator that wouldn't function near freezing and I had to get a two stage regulator to avoid the choking on the ambient plus adiabatic temperature drop suffered by the single stage.

As to the composite regulator it could likely be used as a inexpensive second stage preset to 32psi with a conventional metal single stage regulator preset to 100psi preceding it. Removing adjustments by doing presets would reduce complexity which would make CO2 more user friendly to a wider audience.

I think that people think they're saving significant $$ by letting the tank drop to zero before filling it. IIRC once the tank gets to 400psi there's less than 5% by mass remaining. A bit silly...

jim

Wow, I never thought about that, there would be less than 5 % left at 400 psi. I use a Victor dual stage and love that it's output is rock steady as the cylinder empties. Since I use the Victor with 20 OZ Paintball cylinders because of space limitations, it is nice to be able to run it until empty if I want. I get 4 to 5 weeks out of 20 OZs. In retrospect, It might be much cheaper to run a single stage regulator and just swap the cylinder as soon as you see the input pressure needle move.

 

[Gerryd]

Hi all,

I was looking at it from a cost and component quality standpoint compared to some popular on-line units....

If you look at 4 online retailers (that I know of) that sell units between say $250-300 usd we find:

Rex Grigg
GLA
Sumo
Red Sea

All of these AFAIK offer single stage regulators, and only the Sumo has the option for the IDEAL 52-1-12 but w/o the vernier handle. I am pretty sure the solenoids are not burkert 6011s which are top of the line.

I personally have the Sumo/ideal combo and it has worked fine for several years now with no issues whatsoever. I just wanted a newer and better setup is all. I have no agenda against retailers and capitalism! I was going to get another one but decided to go this route. I also checked out the GLA model as well..I think they all work fine....

I recently built a brand new Victor dual stage/6011 solenoid, V52-1-12 NV, brass check valve, Swageloc post body, etc for UNDER $500 total w/shipping. I think that the quality of these components are worth the extra $ as opposed to a plug and play retail unit.

The parts thanks to Left C and Matt F are know more well known if the desire to do a bit of research is there..

Once I understood more about what went into the build and more about the individual components/parts, it seemed worth the extra $ to build one..

While the cost is almost double the retail unit (not insignificant!!!) the biggest bite was the regulator itself which cost new what the retail units compete setups cost I completely understand the budgetary concerns....but think that second hand regulators are reasonably priced and available with a bit of effort..

I just think that since c02 is so toxic to our fish, that I should have top notch equipment to use and control it.

I/we spend big $ on top of the line filters, lights, stands, etc, why not for c02????

If I gas $2k worth of fish due to a bad NV opening, or a solenoid stuck open, how will I feel then?

I have done it and it felt really bad, trust me. Not 2K worth, but fish I had had for a long time...

Just my 2 cents.

 

[Jim Miller]

1lb liquid CO2 occupies 0.447L. 1lb of CO2 gass occupies 8.7cuft @STP or 246L. So 0.447L of CO2 @STP is 0.0018lbs. If compressed by 54x to get to 800psi you can squeeze in 0.098lbs before liquification occurs or 10% of the mass of the liquid volume. Letting the pressure go down to 400psi means going down to 5%.

I guess I remembered right.

Jim

 

[Jim Miller]

Gerry

$500 to build a custom regulator yourself for a tank and critters worth thou$ands is proportionate and makes sense. Keep in mind that if you actually paid someone to build that it would have likely cost more like $750.

IMO, for the average Joe who is considering raising their game by adding CO2 to the 75G LFS tank they own, it is way out of proportion.

BTW, you probably remember that I also built an Ebay DS regulator using the information I found here and was quite happy to do so.

Jim

 

[Tom Barr]

I think we can get a company say in China to make one for 150$ with a high grade solenoid.
While we can rationalize these cost, I think it's still a tough sell at the higher cost differences.

No way around except to look for cheaper options there.

 

[Jim Miller]

I think if we enlisted the aid of some good pneumatics engineers and started with a fresh sheet of paper for a design which supported 1mg/sec flow rate and took in to account the end of tank situation we could come up with something a lot less expensive by design which could then be further reduced by off-shoring if desired.

For instance if a single stage worked well down to 400psi perhaps the solution to eotd is to just open a blowoff valve when the outlet chamber pressure gets above some defined pressure like 60psi? As long as the relief valve is resettable for at least 100 cycles it would be good for 50 years.

Some costs are just proportional to size. There's no reason all of this stuff can't be done at 10-32 gauge given the extremely low flow rate rather than 1/4" as long as the masses of the bits are reduced to avoid breaking by canteliver torques.

Preset pressures rather than adjustable ones gets rid of big handles on valves. No one really cares what the pressure is as long as it is constant and reasonable.

Solenoids get large and power consumptive if they're expect to hold back big pressures. Reliable solenoids can also double as needle valves and be pulsed to emit a volume of gas on timed basis. The Clippard Mouse is a good example.

If you want to stick to needle valves then getting to a design that doesn't cost the better part of a $100 with a vernier dial would seem to make sense.

Brass instead of stainless, chrome or nickel plate would be perfectly acceptable in the benign environments these work in. I still think the composite bodied regulator is worth a look.

Jim

 

[Matt F.]

In my limited experience, people are willing to pay for quality products. At one time, American-Made products were synonomous with quality and durability. Recently there has been a trend by industry to ship manufacturing jobs overseas. The "global market" has created its own economy. Quality has gone down and so has the price. Is this a good thing from an ethical perspective? What we purchase and how we spend our personal money says a lot to these manufacturers.

Should we support the little guy in ND who makes a quality product (has had contracts with aerospace) and pay for quality, or search for a cheaper alternative? I think Big business' search for a cheaper alternative has been the cause of a laps in quality. It's trickled down into our hobby. It's a viscious cycle, and the only control we can assert is through critical consumerism.

Should we support a local business that only has access to inferior designs and poorer quality or surpass them completely and build our own?

I think the dilemna faced by big business is to survive all the while upping their profit margin.

The end result is to produce a cheap "marketable" product that almost anyone can afford. Counter to ADA's stated philosophy, many manufactures take shortcuts and the quality of the components go down. We experience problems with these units and seek a higher quality alternative.

Do you buy a student grade trumpet for a talented high school student in HS band or do you buy the silver yamaha 6335? Is there a justified cost difference?

Here in lies the choice hobbyists face.

You can't start up a business using used regulators bought off ebay. I don't know anyone that would back a waranty based on a used regulator.
I think GLA used to offer a VTS253A-1993, but it didn't sell and he didn't make much profit, so ho offloaded his stash of these regulators and went with the cheaper smith single stage regulators ($60 new). He makes a nice markup for building them and they sell (regulator and needle valve are american made, not sure about the clippard like solenoid).

I think there is a real fascination when it comes to quality equipment. Regulators in great shape that were used in a medial/lab facility prior to closing are usually in great shape.
I don't think there is a certain "use-by" date as suggested in this thread. Most of these units can be rebuilt if any problems arrise. They are made to last. The same can't be said for most hobby-grade regs.

Just my thoughts...sorry they are all over the place.

 

[Matt F.]

I forgot who I was talking to..maybe it was my buddy Kavicy, but he made a good point!

Those of us who invest in DSRs are in a different market niche than standard hobbyists. 90% of the market is satisfied with standard hobby grade regulators.

Maybe only 10% of us or less (a minority--true hardcore obsessed hobbyists) the people on TBR and other more local forums) strive for more.

Unfortunately, places like AFA are in the west coast's cultural hub of planted tank ethusiasts.

fwiw, I think aquariumplants makes their own regulator, a single stage, too.

 

[Matt F.]

I think if we enlisted the aid of some good pneumatics engineers and started with a fresh sheet of paper for a design which supported 1mg/sec flow rate and took in to account the end of tank situation we could come up with something a lot less expensive by design which could then be further reduced by off-shoring if desired.

For instance if a single stage worked well down to 400psi perhaps the solution to eotd is to just open a blowoff valve when the outlet chamber pressure gets above some defined pressure like 60psi? As long as the relief valve is resettable for at least 100 cycles it would be good for 50 years.

Some costs are just proportional to size. There's no reason all of this stuff can't be done at 10-32 gauge given the extremely low flow rate rather than 1/4" as long as the masses of the bits are reduced to avoid breaking by canteliver torques.

Preset pressures rather than adjustable ones gets rid of big handles on valves. No one really cares what the pressure is as long as it is constant and reasonable.

Solenoids get large and power consumptive if they're expect to hold back big pressures. Reliable solenoids can also double as needle valves and be pulsed to emit a volume of gas on timed basis. The Clippard Mouse is a good example.

If you want to stick to needle valves then getting to a design that doesn't cost the better part of a $100 with a vernier dial would seem to make sense.

Brass instead of stainless, chrome or nickel plate would be perfectly acceptable in the benign environments these work in. I still think the composite bodied regulator is worth a look.

Jim

A couple things:

1) I'd be mnore inclined to buy a regulator with those knobs so that I can have more adjustability in the long run. This is good if you want to use the reg for multiple tanks, or need to increase working pressure for some reason (purging the lines, etc.). I think adjustability and precise adjustment is what makes DSRs far superior to the broad strokes of other designs.

2) Fabco is comming out with a new NV-55 with 1/8" npt ports (beginning of March). See thread in this forum. It's about 1/3 the price of the Ideal Valve for those that don't want to spend the $100. Personally, I bought two V54-1-12, which are quite a bit more than $100. I think they are worth it and would buy again.

3) I wouldn't recommend nickel as a finish. Over time, even in a nice indoor enviorment, you can see some greenish tarnish. The VTS253A-1993 is a chrome plated version of the VTS253A-320, which is brass. The VTS253A-1993 is actually cheaper than the brass counterpart. brass isn't necessarily cheaper.

 

[Jim Miller]

The notion of good engineering to design a purpose built device appeals more to me than an off-shore knockoff. I think there is room for many feature and price points. I remember fooling around with CO2 in the late 90's before giving up on aquariums for a while. There was very little going on then. The breadth and quality that has come along in 10 years is pretty amazing. However most of what is out there is repurposed industrial material rather than purpose built for our flowrates.

One more thing: I found that I had to go buy a bigger crescent wrench to tighten the CGA-320 CO2 fitting on my tank. No big deal for me but think about how few people have any notion of doing such a thing? The paintball tanks are much more user friendly in weight and attachment method, not requiring a wrench at all. If a proper purpose built CO2 dispenser is going to be a typical aquarium item it is much more likely to be attached to something like a 24oz (1.5lb) paintball tank and refilled at a sports store rather than at an out-of-the-way industrial concern. If a 10lb tank lasts 6 months (or more) then a 1.5lb tank would require replacement monthly, be cheap enough to have a couple around in case you forgot to get it refilled and small and light enough to stash anywhere. A typical industrial dual stage regulator with 1/4" post body hardware outweighs such a tank by several times over.

My propane tank doesn't require a wrench either.

Jim

 

[Tom Barr]

As you can see, there are several ways to skin a cattail.

I do not think sayign a dual stage is the only way.
I'm sure many think that they are however.

I'd rather folks know more, enough........about CO2 equipment to see that a good valve or a good reg works fine over time and usability.
I rarely adjust a reg, I do however adjust the vernier handle on a good valve often.

I've bought a few dual stages on line used, they all had some leaks or other issues
Matt and I discussed it some in person.

Fine if you wanna run through and fix each part and redo them, find the parts etc.
I did not.

I just went and got the nice valves and use my Victor singles which have been running just fine for the last 15 years for one of them.
Never had any issues.

With Clippard valves and other valves, I did.
Not so with Nupro and then SWagelok and certainly none with Ideal.

So that control point is well documented via experience.
Not only that, we have had plenty of spirited debates about a high grade valve and what occurs when the tank nears the end of the volume.
These go back to Gomberg Days when he claimed folks did not even need a vlave at all........just a 40$ cornelius reg.

I "shat" you not.

7 Folks in the local club killed everything in their tanks, I went after the issue, but was a bit nicer than normal, but many where simply after Gomberg ever since.
I think after that, folks really spent a lot of time looking at valve issue closely.

With high back pressure, this issue is worse ....than say....... with little backpressure.
Adding a valve mitigates this even farther.

Disc and other high pressure devices seem to be the folks that had the deaths.
This is not much an issue when my tanks run out using needle wheeling methods, it's one of the reasons I switch from mazzei/disc and others.
I like to see the tiny bubbles, but........I'd give that up fast for stability, safety and consistency.
I think the Ideal valves are great, less parts hunting and buying them new also makes finding them easy.
A Victor medalist CO2 runs about 60$ here.

The valve cost more than the reg.
The diffuser for a NW runs maybe 15-30$ tops for any size tank to 250 Gal.
Clippard in line Check Valves seem pretty good so far(not the barbed end ones, the 1/8" FPT), the needle valves suck, but for 18$.....?

Good solenoid, now I do not think folks would have any issues with Single vs say Dual.
Good tubing thick walled etc.

Are we getting more out of the system with dual vs single with the above?
Does one prevent where as another does not?
Not that I can see or have evidence of.

 

[Matt F.]

yeah, you have to be careful on ebay not to buy defective regulators. It's really hard to tell since a lot of the sellers do not test the units prior to selling. Consumers beware if you buy used products.

But,

out of the 20-30 regulators I've bought used, only about 1 or 2 have been questionable.
In fact I got my SGT500 from ebay (listed as new) and it's perfect in every aspect (quality and function). I just picked up a used (lab surplus) HPT 500 for $60 in great shape...

I don't think these regulators go bad that often. SOme are really ugly, worn, or burnt...lol I wouldn't buy those in bad shape.

I think the key to buying a used regulator on ebay is to look for lab surplus, closures, etc. These units are often in the best shape mechanically.

When it comes to building regulators for others (e.g. GerryD), I suggest they spend the extra dough and buy new to avoid all the potential headaches.

If you are able to secure a nice used dual stage for $20-40 and it's for you, there is no problem going this route. If something is faulty you'll know it as soon as you test it. and you're out $20-40. You can reuse all your post body parts, etc. (so as long as you buy quality post body components, you can swap them).

So far, I've had some good luck finding servicable used units.

 

[Gerryd]

Hi all,

This has generated a great discussion! I can see both side much clearer now...

I will say that my audience is more specific and NOT geared towards the mass consumer...this forum is where I spend 99.9% of my posting/forum interaction, so I kinda know the audience already Many of us do have the skills or $ to get high quality. I don't see many folks here promoting junk so far!!!!

I also would be happy to purchase a nice plug and play unit and have done so with the Sumo for good service and excellent results....

I am only saying that I am happy to help those that WANT to go this route...I am not out to convert the masses..

If noone asks for help, I am not going to lose any sleep over it

I guess it is like Oz unmasked for me when you see what goes into it and what could be with a bit more effort/$.

My Sumo single stage and 52-1-12 has worked fine for years with no issues as stated....