Oxygen Concentrator Specs

[periwinkle]

I've had my home studio setup since October of 2009. I'm finding it takes super long to make the simplest of beads, and I'm thinking my oxycon is the culprit...

So I'm wondering about whether I need to buy a second oxycon or fix the one I have (or maybe do both!) I have an Invacare Homefill Compatible SensO2. It says 5 on it. Now, I was talking to Jay at HobbiesforUs.com (he sells refurbished oxycons), and he was trying to explain to me the difference between LPM and psi. What I really want to know is: will a second oxycon give me that much more heat power to melt transparent glasses? And am I looking at LPM or psi as my guide? I only use soft glass, but I find that it takes so long just to make the simplest bead. A small heart might take 25 minutes, but at the local studio with oxygen tanks the glass melts so fast, it is way way faster.

The oxycon I'm looking at buying is a DeVilbiss 505 Model 10 PSI for $235 (shipping included). The way Jay at Hobbiesforus.com explains it to me, since my current oxycon is not getting 5 psi right now and it takes so long to melt glass, I'll most likely get about 7 psi with the two oxycons. To my thinking, if I'm getting about 3 psi right now, if I add 10 psi, I'd be getting about 13 psi, but that's not what he said...I just want to make sure the second oxycon is really going to make a difference. This is a large purchase for me and I want to be sure what I'd be getting is worth it!

Another question I have is: What is the difference between LPM (liters per minute) and psi (pounds per square inch)? How do these affect melting of the glass? I want to be able to encase beads without having to take over an hour just to encase a simple small bead. It takes me probably about 45 minutes to an hour to do the simplest plain encasing - that doesn't include the time to make the base bead, which is about 30 minutes!!

I tend to be slow making beads, but when transparent glass becomes like hot gooey honey in the local community studio within 2-3 minutes and it stays like granite (at home) and only melts about 1 inch of the rod after 10-15 minutes of heating, there's something wrong.

I'd appreciate any help with understanding what it is the difference between LPM and psi. How does it matter whether it's LPM or psi? I've heard so many people say they have a 5, 10 or even 15. I'd like to understand this better.

[houptdavid]

LPM is volume
Psi is pressure

What torch?
What glass?
You should have no problem with a cricket or minor on 5lpm with Effetre.
Bullseye it would be SLOW!
is the DeVilbiss 505 a 5lpm at 10psi

Is the studio using tanked O2?

[periwinkle]

Thanks for explaining that so succinctly, David. I have a Minor using soft glass (Moretti). And, yes, Bullseye is slow, but so is Moretti! There's almost no difference at my torch! Especially when it comes to the transparent glasses.

The outside studio that I use is on tanked oxygen, so obviously I know that's the best.

At home, I have an Invacare Homefill II SensO2 concentrator. It says 5 on the front of it. I believe it supposed to get 5 LPM, but it takes forever to melt transparent glasses so I think it's getting about 3 LPM.

Seriously, I'm exhausted by how long it takes to melt pale aqua or even clear transparent glass. I find I've developed a bad habit of putting my rods nearly at the torch's tip just to keep the glass melting and to make sure it gets hot enough if it's transparent glass. The glass will melt further out in the flame, but the flame seems to get sucked out by my box fan (which is my exhaust system). The box fan sits on a window about a foot above the torch and just behind my station. The fan sits in a window pane and the desk is against the wall where the window is. I'm facing the window. The station is a desk that has an attached shelf on top of the desk part. There is open space between the shelf and the desktop. So the fan pulls the flame around. I often have to stick rods closer to the Minor's end in order to make sure it melts.

Yes, the Devilbiss is 5 LPM with 10psi. So do I want more volume or more psi or does it matter? I read something about making sure the two concentrators have almost the same psi, but if I purchase the Devilbiss it has 10 psi and my Invacare has 5 psi.

[JEK3]

My oxycon (a 5lpm Invacare Platinum XL, essentially the same as yours), when I first tried it, produced a very weak output, barely enough flame to melt ice. I pulled the cover off, and removed the check valve, flow gage, and HEPA filter, replacing them with just a straight piece of tubing that goes through one of the holes in the top where the flow gage was. Easily 3-5 times more O2 output! All those components just added unnecessary restriction. Now I can easily melt boro. Let me know if you want more details on what I did.

[houptdavid]

I can take a garden hose @ 30 psi and have 5 gallons a minute.
I can take that same hose hook it to a pressure washer and have 2000 psi but I will still only have 5 gallons per minute.

You want more volume

Unless something is blocking it it should be getting 5lpm turn it to 5lpm and open your torch all the way, adjust the propane for your flame.
I used a minor on 1-5lpm and then hooked 2- lpm together, much better. Then I got a Regalia even better.

The problem is comparing it to tanked

[kirchybaby]

There is another important factor to understand, which is an equally important component to your problem. Yes the volume of the oxygen flow is important. Yes the pressure of the oxygen is important. But know also that the purity of the oxygen varies from source to source. Some oxygen concentrators produce a gas mixture as low as only 70% oxygen, while others are capable of producing oxygen concentrations greater than 90%, (Tanked oxygen will have a gas mixture whose oxygen concentration is 93% or greater). Also know that the closer you get to the concentrator's maximum abilities, the concentration begins to drop, sometimes drastically. For example, If you are running a 5 lpm at only 3 lpm, you will be getting a higher oxygen percentage in your product gas than if you were running a 5 lpm at 5 lpm. Therefore, if you had a whole room full of concentrators producing 5 lpm capable of say, even 20psi but at only 70% purity, you still wouldnt have as useful a setup than a single 5 lpm producing 90% purity.
Oxygen productivity also diminishes with the age of the device. Your "refurbisher" may not have replaced critical componenets (such as the zeolite sieve, whose efficiency functionally determines your final oxygen percentage). If your refurbisher cannot attest to the oxygen's purity for lack of a purity testing apparatus, then it is safe to assume that the critical components were not replaced, as they couldn't know if it was spent in the first place.
Most applicably, the manufacturers of your torch will absolutely be able to provide you with the necessary pressures and volumes that your torch requires for optimum performance. It's not just some guessing game. Know that their figures assume oxygen purities of around 93% or greater.
So, everyone can stop guessing, just:
1: Contact the torch manufacturer to find your exact needs of pressure and volume for oxygen and fuel gas your specific torch... it might even be on their website!
2: Utilize an oxygen source that you KNOW has a concentration of at least 90% in conjunction with the minimum necessary pressures and volumes required to operate your torch. Piece of cake.

Tah tah!

[JEK3]

The concentrator in question has a sensor that alarms if the concentration drops below 90%.

Also, I have the same one, and I had the same problem until I removed some internal components that were restricting flow.

Here's what I removed:


Here's what it looks like now:


Here's the inside, with me pointing at the new straight tubing I installed to replace the components from the first pic:


The difference was like night and day.

[periwinkle]

Thanks, Joe, David & Kirchy. Joe, do I do what you did? I'm pretty good with opening up my appliances and doing stuff with them, but I've never opened up my concentrator. Would you send pictures and directions to me? My email is: iamperiwinkle@yahoo.com.

David, so if I got two concentrators with 5 LPM, would that increase my output to 10 LPM? Even if each of them only has 5-10 psi?

Kirchy, I've already talked to Peter Norton of Nortel about two years ago. He told me 5 psi is minimum with an oxygen concentrator. I don't remember what he said about LPM, but I probably have it in my notes somewhere. I'm pretty sure I didn't understand it then, either. Certainly less so than now...And I barely understand it even now.

[periwinkle]

Wow, Joe, you already posted the pics...Awesome!!! So how do you know how much volume you are getting if you remove the LPM thing? You said it was better, but if I remove it, I'm wondering if that would help. I have a fear of ruining the thing. Guess I could reattach it if it was somehow worse.

[JEK3]

I don't worry about the volume. I know it's better only because I can get a much bigger flame.

I control the flowrate with the torch itself. If I open it up too much, the o2 purity will drop below 90%, and the alarm will sound, so I just back it off a little.

You'll figure it out pretty quickly just how big of a flame you can use. If you're used to 45 minutes to make a bead, you probably won't go overboard right away.

[artsyuno]

Two fives do not equal 10 when it comes to oxygen concentrators. You will lose a bit when you connect them. It'll still be better than one at 5, though.

[Mike H]

If you use two concentrators that are 5 lpm and 10 psi each you will have double the lpm which would be 10 but the psi would stay at 10 not 20.
I have two concentrators linked together that produce 10 lpm and 10 psi. I run a National 8M with a 30 port tip and it rips. I run the concentrators wide open never adjusting the oxy, just the propane at the torch.

[CSimi115]

I'm a beginner and I bought a used concentrator for $75 2 weeks ago. Well the compressor went last night. Trying to figure out anyway to fix it. (Anyone know where I can get a compressor?) I also have a question about the lpm's. If I can get a concentrator that is a 10 lpm is that so much better?
Thanks
Chris

[Dale M.]

Originally Posted by CSimi115

I'm a beginner and I bought a used concentrator for $75 2 weeks ago. Well the compressor went last night. Trying to figure out anyway to fix it. (Anyone know where I can get a compressor?) I also have a question about the lpm's. If I can get a concentrator that is a 10 lpm is that so much better?
Thanks
Chris

Generally having more oxygen available than a torch needs is a good thing...

Most oxycons are 5 LPM because they are re-purposed from medical industry... To get a single 10 LPM unit you will need to get a unit modified for large output (lpm) or a custom build unit or go to commercial "oxygen generator" (oxygen concentrator and oxygen generator are virtually the same, its only the application that causes description to change)...

As for compressor motor... Look for nomenclature plate on MOTOR, it should have manufactures name, model number and some other specifications.... Try finding the motor from a "parts" dealer on i-net...

Dale

[glasshobbit]

I wanted to say thank you to Joe (JEK3) I thought my used oxycon was toast. I took out the extra stuff as he described and it runs awesome. I had ordered a new one from oxydoc which is coming this week but now I wonder if I even needed to. Thank You Joe.

[cheng076]

I have seen new motor/compressors on eBay often. Just check that the specs are the same.
PJH

[JEK3]

Originally Posted by glasshobbit

I wanted to say thank you to Joe (JEK3) I thought my used oxycon was toast. I took out the extra stuff as he described and it runs awesome. I had ordered a new one from oxydoc which is coming this week but now I wonder if I even needed to. Thank You Joe.

Anything I can do to help this community, which has helped me out immensely!

Just think, with a second oxycon, your torch will ROCK!

[Melinda]

Originally Posted by JEK3

Anything I can do to help this community, which has helped me out immensely!

Just think, with a second oxycon, your torch will ROCK!

Thank you for helping. I was wondering if you knew where or how to hook 2 concentrators together. I'd rather not cut off the metal fittings on my oxy hose.

[Moth]

Originally Posted by JEK3

The concentrator in question has a sensor that alarms if the concentration drops below 90%.

Also, I have the same one, and I had the same problem until I removed some internal components that were restricting flow.

Here's what I removed:


Here's what it looks like now:


Here's the inside, with me pointing at the new straight tubing I installed to replace the components from the first pic:


The difference was like night and day.

Wow...that is the most valuable, helpful post to me that I've seen in months. Thank you so much for sharing that.

~~Mary

[nate-d]

Hi JEK3,
I have a question about removing those components. I have two alliances and I accidentially turned them all the way up past five and the orange light was on stating the O2 level was below normal. I turned it back down to five. If I remove those components will I be getting a descent puity?

[JEK3]

Originally Posted by nate-d

Hi JEK3,
I have a question about removing those components. I have two alliances and I accidentially turned them all the way up past five and the orange light was on stating the O2 level was below normal. I turned it back down to five. If I remove those components will I be getting a descent puity?

Purity is based on the sieve beds. If you try to get too much flow out of your oxycon, the sieve beds won't be able to keep up, and the purity will drop. If you remove these components, it may make it easier to go above the point where the beds can keep up. Best I can say is to give it a try - if it makes things worse, just put the components back in. As I stated above, I use the purity light as an indicator that I need to turn my torch down, and I have no idea what I am actually getting for lpm out of my machine.

Originally Posted by Moth

Wow...that is the most valuable, helpful post to me that I've seen in months. Thank you so much for sharing that.

~~Mary

Thanks! Anything I can do to help. I'm sure I have gotten some valuable insight from your posts, too.

[TheMima]

wow, thank you! I know its an old post but so valuable. Now I'm ready to go.

[drew1492]

Filters also play a big part in purity if you have a dirty filter you are not going to get the purrity you want.

Also on the picture you have with the line you replaced taking out the bacteria filter you can adjust the PSI on it so you can pull a higher pressure out of the oxy con. I pull 15psi out of the same machine at 2.5lpms filling my homefill. You use an allen wrench to jack up the pressure by screwing it in further.

[glassbead]

This is a great thread- I may have to change torches sometime soon, and this may be just what I need to fix everything up! Thanks!

[Roo Blaty]

Ok. Now I really want to look inside my oxycons.

I have 2 older ones hooked together. If I turn one on, the little ball thingy goes to five. When I turn the other one on, they both are at 3.

Peri, I'm so glad you asked these questions. I think you have better idea of what's what than I do! Where is this sieve thing Joe is talking about?

I don't even know how to find out what the psi is...or is that the ball thingy? If so, where does it say the lpm? I only see it listed on one of them. One is like Joe's and says 5 the other says Platinum. I also have an AirSep Elite, but not sure what it is? 10 maybe? It was doing the same thing that Periwinkle had problems with...just not hot at all. That's why I bought these 2 old used ones.

Anyway, this is really a good thread! Thanks Joe and Peri!!

How do I know if I have alarms that will alert about the purity? I guess if they sound, I have them, huh? I've only heard them when I start them up.

[Justin L]

The "Modification" done above is definitely not going to get the best results, and will absolutely lessen the life of your machine!!!

That flow gauge that was removed is in place so you do not demand more oxygen than the machine can make. If you see where the new oxygen hose was connected (small silver cylinder between two larger ones). Thats a "product tank". Its job is to mix the oxygen from the two taller cylinders to provide a constant flow and purity to the user. The oxygen coming out is controlled by the flow meter (removed). If there is no way to control the flow, then the oxygen is going to come out as fast as the compressor can push the air through, and at a much lesser purity. Not advisable! Not to mention the life expectancy of some of the components inside will fall off rapidly if you continue to demand the machine to operate like that.

[LarryC]

Originally Posted by Justin L

The "Modification" done above is definitely not going to get the best results, and will absolutely lessen the life of your machine!!!

That flow gauge that was removed is in place so you do not demand more oxygen than the machine can make. If you see where the new oxygen hose was connected (small silver cylinder between two larger ones). Thats a "product tank". Its job is to mix the oxygen from the two taller cylinders to provide a constant flow and purity to the user. The oxygen coming out is controlled by the flow meter (removed). If there is no way to control the flow, then the oxygen is going to come out as fast as the compressor can push the air through, and at a much lesser purity. Not advisable! Not to mention the life expectancy of some of the components inside will fall off rapidly if you continue to demand the machine to operate like that.

Oh man! You mean theres no free lunch?

[Justin L]

unfortunately not LOL

I read above that the user was using the "Low O2" light as an indicator on when to turn down the torch until the "normal o2" light came on. Thats essentially what the flowmeter does, so i'm kind of at a loss on how it works any better than before????

The concern I have is for people that have a machine without the low o2 light. They will never know and will continue to use the machine incorrectly. Then they will wonder why its worn out and wont work

[JEK3]

Originally Posted by Justin L

unfortunately not LOL

I read above that the user was using the "Low O2" light as an indicator on when to turn down the torch until the "normal o2" light came on. Thats essentially what the flowmeter does, so i'm kind of at a loss on how it works any better than before????

The concern I have is for people that have a machine without the low o2 light. They will never know and will continue to use the machine incorrectly. Then they will wonder why its worn out and wont work

You are right. I don't recommend removing the flow gauge if your oxycon doesn't have a purity sensor. Removing the other components will still show some improvement.

It only took me about ten minutes to find out how large of a flame I could get without alarming the purity meter. Since then, I have just visually adjusted it, and haven't had any problems with alarming the meter.

The improvement comes from the fact that, with all those components in place, the restriction was so great that the oxycon was incapable of providing enough flow to the torch to produce a reasonable flame.

By the way, I have since reinstalled the flow gauge, but I keep it all the way open so it provides minimal restriction, and throttle the flow at the torch.

[LarryC]

Originally Posted by JEK3

You are right. I don't recommend removing the flow gauge if your oxycon doesn't have a purity sensor. Removing the other components will still show some improvement.

It only took me about ten minutes to find out how large of a flame I could get without alarming the purity meter. Since then, I have just visually adjusted it, and haven't had any problems with alarming the meter.

The improvement comes from the fact that, with all those components in place, the restriction was so great that the oxycon was incapable of providing enough flow to the torch to produce a reasonable flame.

By the way, I have since reinstalled the flow gauge, but I keep it all the way open so it provides minimal restriction, and throttle the flow at the torch.

Have you considered that the system might have been designed with those components in place for a reason? I am a design engineer and it is common and acceptable practice to choose components on the system level. This means that removing any one component may cause excessive stresses on some other part beyond it's specifications. I dont know that this is in fact the case but it is somewhat likely and could cause premature failure. If you have enough knowledge of the product to know that this is definitely not the case, please let us know as I too like to tinker with things a bit myself