Ultimate mixer

[irish fixit]

Honestly officer it all started innocently enough. I was just looking for the ultimate mixer. Oh you want to whole story. Well here goes.


The quest for the Ultimate Gas Mixer

Well being the middle of a upgrade in welding equipment has sent me on the search once again for the best way to supply inert gases to my welders. The first attempt had mixed results. It worked kinda sorta but not as well as I would of liked.

I started out with two flow meters straight on the tanks and a 50' hose to the cart with the wire feeders on it. Lesson #1 the hose contains a large amount of gas that wants to spew out all at once when the valve on the feeder opens. Oops.

Next attempt leave regulator on tanks and move flow gauges to cart (which means adding another hose the already large umbilical running to cart). This seems to help but I still have problems with the start of the welds with the S-64 and Dimension 400 running solid wire. It takes a little while for it to settle down and make a good weld. Never really figured this problem out even after adding a valve on the feeder to limit the rush. Finally decide it's a function of the old welder.

But it's out with the old and in with the new (well new to me). This time I'm going for light, portable, easy to change over, and space saving. Luck has allowed me to get some pretty good deals off ebay in the last couple of months making this possible.

Now how to get the gas to the cart/welder/suitcase feeder. Idea what about a hose reel. A quick check shows the HF now has there 50' industrial hose reels on for $90. Hmm cheaper than I paid for the 3 I have now. Even more interesting is they show a torch version for $129. Hmmmmm. More thinking. What if I convert two standard reels to welding leads. Hmmmmmm. Interesting. Now what else can I do. Lets see we've got a torch reel, two welding lead reels, and a inert gas reel. Might even add a second torch reel. Now where to mount them. What about over the welders? Hmmm. By george I think I've got it. Let's make a mount up there to hold 5 reels and take it from there. Now what to make it out of. Search the place over no 8" channel. Hmm. What about the pile of model A frames over in the corner that might work.

(See first pic below)

Now the old mixer had a kludge of a decent Victor flow gauge with a old flow meter I had laying around from some auction in the past. I never could figure out a accurate way of calibrating the old flow meter. So research flow meters. Wow those are pricey.

Hmm. Lets see whats on ebay. Hmm. Here's a bunch of old flow meters from a scrap place. Research what info I can find from the pictures and sure enough at least a couple of them seem to be about the right size. Get those in and test them. Yep two of them are the right size and seem like they would work. Look at hose reel and think for a minute. Hmm you know it's going to take a lot of gas to purge the new mix going from Mig to Tig. Hmmmm. What about a second reel just for Tig and one for Mig. Hmmm. If I do that I really should have some more flow gauges. Let's see what ebay has to offer. Wow nice set with at least one meter having the right tube. Hmm. Maybe the smaller tube could be used for Helium. Research again. Sure enough they'd work. Get second set of flow meters in. They're in much nicer condition than first set and same brand. Now I can mix and match parts for a good set. Wow look at all those flow meters.

(to be continued)

[irish fixit]

Now how to build the mount for the gauges chosen. Hmm. Well 1 1/2" angle might make a good choice. Hmm what spacing for the gauges. Lets leave 1 1/4" space between for strap I know I've got so I can label everything. Hmm. Maybe I should measure the strap to see exactly how wide it is. Naaa it can't be that bad I'll just drill the holes a little oversize to allow for adjustment. Cut angle, low out holes, drill holes. Hmm somethings not right here. Oops messed on on the first spacing of the second angle. Back to the saw for another angle. Lay out holes and double check spacing. Everythings right so lets drill. (see first pic).

Ok. Bolt up meters to angle square it up and everythings going just great. (see second pic)

Now for the strap to go between the gauges. 1" x 1/8" is just right for the top and bottom. Tack that in place. Now lets get the 1 1/4" x 1/8" strap. Yep that's it cut it to length and deburr. Now lets get these tacked up. It'll be a piece of cake. Hmm. Why isn't the strap fitting between the gauges. Check with tape the gauges are spaced right. Check strap that looks right. Look closer wait a minute why is the strap measuring 1 3/8". (note to self when you think it might be a good idea to check actual dimension of stock don't be lazy just do it) (second note to self don't be so cheap and get the new tape down from the wall when the old one has the marks half worn off). (must punish self now by grinding 1/8" from all 5 straps). Grind and grind and fit. Now they all fit and are in place. Whew.

Wait a minute are those the guys in white coats coming. Well can't stick around. I'll add more when they let me out of the room again. :dizzy:

[farmersamm]

Uh..............I hear modern medicine has developed many new treatments, and all sorta pills, for your condition

[irish fixit]

Uh..............I hear modern medicine has developed many new treatments, and all sorta pills, for your condition

I think I'm a lost cause. :-)


They finally let me out again so I could do some more work on it.

After umpteen phone calls, a few emergency jobs, friend advise seminars, and a dozen trips to the hardware store I did make a little progress on it today.

Got finish welded, painted, most of the fittings installed, and started the labeling before giving up for the day.

First pics are of one emergency repair. They're trying to get a combine ready and couldn't find a new turbo oil line. The old one was leaking at a ferrule. Being odd ball sized (probably 10mm) and compression fittings made it tough. Finally had to braze JIC fittings onto the original and make a hydraulic hose for them.

Fourth pic is the front. I've still got to label the increments for each of the flow meters but hopefully you can see where I'm heading with it. The last is the back. What look like nipples coming out of the top of the flow meters are actually check valves. Top left outlet on the tee will be to the MIG hose reel (which I can also use for backpurge for the TIG). Top right will go to the TIG hose reel. Bottom left is the inlet for the Helium. Bottom right tee is for the Argon, and under the plate holding the Victor gauge on is the inlet for the CO2. I'll use the Victor gauge for purging tanks when welding on them.

When done I hope to be able to mix water ever proportions I want whether tri mix for SS MIG or straight Argon for aluminum MIG.

[PapaLion]

It's a soda fountain for weldors... handy for you, well done Irish, Samms just miffed 'cus ya' did it in Texas. Of course, he is a stick afficienado, and thus life is less complex. probably a no smoking sign would be prudent?

[irish fixit]

It's a soda fountain for weldors... handy for you, well done Irish, Samms just miffed 'cus ya' did it in Texas. Of course, he is a stick afficienado, and thus life is less complex. probably a no smoking sign would be prudent?

Thanks. I have to remain as versatile as I can. I never know what's coming in the door next. Thus I'm sparing no expense on this project (and it is getting expensive when added all up).

As for Sam I think he just likes playing with his sticks. :-)

Shields are going up now. :-)

[farmersamm]

Fittings have become a real nightmare. Stuff is put together from parts supplied by vendors all over the world, and metric/sae is mixed on the SAME machine.:gunsfirin

Wheat destined for hay is being cut here now, but the wheat destined for grain won't be cut for quite a while.

The gas stuff looks like it's coming together. I'd be thrilled to be able to run gas, BUT I NEED WALLS AND A ROOF:cry::cry:

[irish fixit]

Fittings have become a real nightmare. Stuff is put together from parts supplied by vendors all over the world, and metric/sae is mixed on the SAME machine.:gunsfirin

Wheat destined for hay is being cut here now, but the wheat destined for grain won't be cut for quite a while.

The gas stuff looks like it's coming together. I'd be thrilled to be able to run gas, BUT I NEED WALLS AND A ROOF:cry::cry:

Fittings are a nightmare for me since I make hydraulic hoses. There's way to many and they're using different fittings all the time. I have a lot of $$$$ tied up just trying to get the more common fittings in stock.

It's about the same here. I fixed a shaft for a swather shaft last week. Had to build up where the bearing had worn the shaft and turn it down. But I'm seeing more and more combines heading south. This was for a local guy who has a mechanics shop but also has some combines he runs in season. He helps me way to much for me to refuse to do the work.

If you haven't noticed I need a lot more walls and roof around here. That big drill has reduced my working area to where I can barely get the bed of a pickup in here. To top that my dad lost the lease on a place where I have machines stored in the barn. I've got to build on in order to move those out. Fortunately the guy who's got it now is understanding and not pushing for me to move them yet.

[irish fixit]

. probably a no smoking sign would be prudent?

Forgot to respond to this last time.

On the mixer everything's inert so no problem there. However since I'm a drop dealer as well there is a rather large supply of acetylene nearby so it would be prudent.

[SundownIII]

Irish,

Lot of hard work and time/effort went into that project.

Actually, in discussing gas blending with Smith, the process is considerably more involved than it appears on the surface. Their mixers take a gases' specific gravity into account when sizing the orifices for the different mixers. Than and how the gases are directed during the "mixing" process.

It would be interesting to put a gas analyzer on your output stream to determine the accuracy of the system. People, in the know, that I have talked to claim it's impossible to accurately blend welding gasses with a Y setup.

Or you could had just gone this route:

[SundownIII]

Irish,

The Thermco mixer shown in the left photo mixes Argon/CO2 in any proportion from 0-100% CO2. That is the mixer I use most frequently. I feed it from a 330 Argon and a 50# CO2 bottle. I does not have a built in flowmeter. Delivers mixed gas at 50PSI (internally adjustable) to a Smith flowmeter which I mounted on a magnetic base. That flowmeter has a short (6' ) hose with a quick disconnect. Set the flowmeter on the mig of choice, plug in the gas, set flow, weld. Works really well (the mixer) when going from short circuit to spray. Especially with some of the gas mixes called for in pulsed spray.

I have had the output (mixed gas) checked and it's always been within 1% of what was dialed in.

The two Smith mixers are used for blending Argon/Helium and Argon/Oxygen. They, as you probably know, have their own built in flowmeters. Mixers require the use of straight regulators, not combo regualator/flowmeter.

Keep us updated about how your system works for you. I really like the hose reel idea. Will have to check out putting a reel on the Thermco system.

[down19992000]

Sundown if I may ask where did you find that mixer and what was the price? Thanks...

[SundownIII]

Down,

The Thermco mixer (Argon/CO2) has a retail price of about $3,500.

Before you fall out of the chair:laugh:, let me assure you I didn't pay nearly that much for it.

Bought it off e-bay. It as a "NEW", but old stock item. A major company had purchased the unit and never used it. Sat on a shelf for a couple years. Turned it over to a wholesaler who listed it. Got it for considerably less than half of retail.

It really is a very sophisticated unit, compared to the Smith mixers. Ultra high quality components in the build. Has internal regulators for both gases. Gas is delivered from the regulators on the bottles at 125PSI. Internal regulators step it down to 100PSI where the mixing occurs. It then stores a small quanity of mixed gas. That mix is then further regulated down to 50 PSI (internally adjustable) which is the regulated pressure used by the Smith multi-gas flowmeter.

Actually, when you go inside the unit (required to adjust the output pressure), you begin to see why it sells for what it does.

The Smith mixers retail for around $1,200-1,300, but they can be found used on e-bay for sometimes around $500. Great little mixers and there's not much to go wrong with them. Can't see anything about them that would "wear out" over time. If I hadn't gotten such a good deal on the Thermco, I'd probably be using a Smith for mixing Argon/CO2.

I use a Smith for mixing Argon/Helium for tig welding heavy aluminum, and another Smith for mixing 98%Argon/2%Oxygen (spray mix). Both work very well.

[irish fixit]

Irish,

Lot of hard work and time/effort went into that project.



Yep. It's been an adventure.


Actually, in discussing gas blending with Smith, the process is considerably more involved than it appears on the surface. Their mixers take a gases' specific gravity into account when sizing the orifices for the different mixers. Than and how the gases are directed during the "mixing" process.


The next step is the calibration of the meters to the specific gravity. As for the directing I'm of two minds on that. I know from talking with my buddy at the local gas company that they go to the trouble of getting a laminar flow before mixing. But he his thoughts are that
the turbulence at a ell should do the mixing. My thoughts are that if it's not mixed by the time it goes through 50' of hose then it's not going to get mixed. I do know that a setup similar to mine is used in labs. If you'll look at the pic above with all the different rotameters (the correct term for these flow gauges) arrayed out the one on the left on a stand is made to mix gases. The tube in the middle is the mixer. I've not got around to taking it out and seeing how it was made. I tried to find a parts break down for the Smith mixers to try and see how they where setup before going into this project. I can think of a few different methods that they could of used to do what they're doing.

I do know of one guy who managed to do argon helium with simple flow meters and a Y with check valves setup for his TIG. It worked for him. Time will tell if I'm wasting my time on this project (hope not).

It would be interesting to put a gas analyzer on your output stream to determine the accuracy of the system. People, in the know, that I have talked to claim it's impossible to accurately blend welding gasses with a Y setup.


That would be nice. Hmm. I wonder if the gas analysis company here in town are setup to handle inert gases. It's been a while since I've done a job for them. Maybe I'll run into them some day and ask.

Or you could had just gone this route:



That's some real nice (and expensive) equipment you've got there. I would of loved to of done that but it's out of my price range right now.

[irish fixit]

Irish,

The Thermco mixer shown in the left photo mixes Argon/CO2 in any proportion from 0-100% CO2. That is the mixer I use most frequently. I feed it from a 330 Argon and a 50# CO2 bottle. I does not have a built in flowmeter. Delivers mixed gas at 50PSI (internally adjustable) to a Smith flowmeter which I mounted on a magnetic base. That flowmeter has a short (6' ) hose with a quick disconnect. Set the flowmeter on the mig of choice, plug in the gas, set flow, weld. Works really well (the mixer) when going from short circuit to spray. Especially with some of the gas mixes called for in pulsed spray.


REALLY nice mixer you have there. I just got my Optima pulser which is what's spurring me on for my mixer.

I guess you are aware of the fact that the Smith flowmeters are calibrated for 80psi. My conversion charts are in the shop right now so I don't know the exact difference from 80 to 50 psi. It's not a lot though. I know that the 80 to 20 psi is just over 1/2 the scale reading.

I'm calibrating my meters at 20 psi to help reduce the surge from the lose hose. I'm going to have to add some form of metering at the quick release to prevent to much surge even then.

I have had the output (mixed gas) checked and it's always been within 1% of what was dialed in.

Great.

The two Smith mixers are used for blending Argon/Helium and Argon/Oxygen. They, as you probably know, have their own built in flowmeters. Mixers require the use of straight regulators, not combo regualator/flowmeter.


Do you run the Smith mixers with a long hose? I was wondering since my experience with the long hose before and the surge problem.

I do know about the regulator issue. I've got stems to put in some good oxygen regulators I've collected and had rebuilt over the years which I'm going to use for this project.

Keep us updated about how your system works for you. I really like the hose reel idea. Will have to check out putting a reel on the Thermco system.

Will do.

[SundownIII]

Irish,

I hope you didn't take my comments wrong. I think what you've done is awesome and shows that you've really "done your homework" when it comes to mixing gases.

I think the reason people get by with using the Y setup for mixing Argon/Helium is because you have a wide range of percentages to deal with. For instance, adding say 25% Helium will increase the heat at the bead (as will 23% or 29% etc). You don't have to be "right on" to see the benefit. Same applies as you increase the Helium percentage.

On the other hand, mixing Argon/CO2 for spray transfer or pulsed spray, a few percentage points can make a big difference in the way it affects the puddle. For instance, I can see a difference in say (for pulsed mig) a 5% CO2 mix and an 8% CO2 mix. On the Optima pulser there are actually different programs for a 2% mix and a 5% mix. I think it is here that the accuracy of the equipment becomes more critical.

Keep us updated on your progress. Gas blending can yield tremendous benefits. If there's a better or cheaper way to do it, there are a lot of people who could benefit.

Ironically, I first got into mixing my own gasses to reduce the number of different bottles of gas it was necessary to keep on hand. The more "into it" I got, the more I realized how different gas mixes affect the final bead. I've found "favorites" that I probably would have never tried had I had to buy a whole bottle of gas to "try it out".

I do feel that I have somewhat reduced my gas costs (larger bottles = lower per cubic foot cost) by using the mixers. Don't know that it's necessarily reduced the total number of bottles that I keep on hand. From your photos, looks like you run into the same issue.:)

For example, here's what I normally keep on hand:

2-3 large Argon (330's) Mixer, tig, backup
2 50# CO2 Mixer, backup
1 Tri-Mix (330) Stainless mig
1 Large (330) Oxygen (Ox/Ace)
1 Large Acetylene (a 300 L cylinder)(Ox/Ace)
2 Small Argon (125's) Backup, portable work
1 Smal Helium (125) Tig
3 Small (125, 55, 40) C25 portable mig.
1 Small (40) Acetylene (small torch)
1 Small (125) Oxygen (small torch)

I "own" a couple of the larger bottles and all of the smaller ones. My gas supplier gives me a really "good deal" on yearly leases on the remaining large bottles.

Running out of gas/mix in the middle of a project has not been an issue for some time now.:D

[irish fixit]

Irish,

I hope you didn't take my comments wrong. I think what you've done is awesome and shows that you've really "done your homework" when it comes to mixing gases.

Not wrong at all. I'm more than glad for more input on this thing. The more info and points of view the better.


I think the reason people get by with using the Y setup for mixing Argon/Helium is because you have a wide range of percentages to deal with. For instance, adding say 25% Helium will increase the heat at the bead (as will 23% or 29% etc). You don't have to be "right on" to see the benefit. Same applies as you increase the Helium percentage.


Agreed.

On the other hand, mixing Argon/CO2 for spray transfer or pulsed spray, a few percentage points can make a big difference in the way it affects the puddle. For instance, I can see a difference in say (for pulsed mig) a 5% CO2 mix and an 8% CO2 mix. On the Optima pulser there are actually different programs for a 2% mix and a 5% mix. I think it is here that the accuracy of the equipment becomes more critical.


Definitely agree. This is a lot of the reason why I'm going to so many pains on this build. My past mixer was a definite hack. I had a old rotameter that came from a auction lot and the rotameter that was on my good Victor flowmeter setup. I just had to experiment with the old rotameter to guess at what it was flowing. I'm now positive that I never was close on the actual flow. I wanted this one to have all the same kind of meter. I got lucky and found good deals on the same brand meters which I could easily get the calibration sheets for. I'm stuck with some excess meters but maybe once I get done I'll resell them. Then again maybe not. It's nice to have spare parts around.



Keep us updated on your progress. Gas blending can yield tremendous benefits. If there's a better or cheaper way to do it, there are a lot of people who could benefit.


That and this discussion is one reason I'm documenting this build here. I want input from people who have had other experiences than mine and I want other people to benefit from my experiences.

Ironically, I first got into mixing my own gasses to reduce the number of different bottles of gas it was necessary to keep on hand. The more "into it" I got, the more I realized how different gas mixes affect the final bead. I've found "favorites" that I probably would have never tried had I had to buy a whole bottle of gas to "try it out".

I know there's a definite change in the weld from my past hack mixer.

I do feel that I have somewhat reduced my gas costs (larger bottles = lower per cubic foot cost) by using the mixers. Don't know that it's necessarily reduced the total number of bottles that I keep on hand. From your photos, looks like you run into the same issue.:)


Actually it's not as bad as it looks. I'm a drop dealer for the Praxair dealer 60 miles away. Most of those bottles in the pictures are stock to service my customers.

For example, here's what I normally keep on hand:

2-3 large Argon (330's) Mixer, tig, backup
2 50# CO2 Mixer, backup
1 Tri-Mix (330) Stainless mig
1 Large (330) Oxygen (Ox/Ace)
1 Large Acetylene (a 300 L cylinder)(Ox/Ace)
2 Small Argon (125's) Backup, portable work
1 Smal Helium (125) Tig
3 Small (125, 55, 40) C25 portable mig.
1 Small (40) Acetylene (small torch)
1 Small (125) Oxygen (small torch)

I "own" a couple of the larger bottles and all of the smaller ones. My gas supplier gives me a really "good deal" on yearly leases on the remaining large bottles.

Running out of gas/mix in the middle of a project has not been an issue for some time now.:D

I get a good deal on my leases since I'm a dealer. My leased bottles are.

2 K(225+) oxy one for truck and one for shop
1 AC4 (125) acetylene for the truck
1 AC5 (300-400) acetylene for the shop (I do a lot of large brazing and heating)
1 T size C25 (330) mix for my Millermatic 252
1 T Argon for my TIG, and mixed for my other MIG's
1 50lb C02 for mixing and purging

I also own a 40 cu ft bottle for portable use that I used to have C25 in for my Millermatic 135 then 175 I used to have. But I've purged it and changed to pure Argon since I now have the Dynasty 200DX.

The rest in the pic are stock.
16 K oxygen's
3-4 S oxygen's (this company actually calls both 125 and 155 bottles S)
1 80 oxy
1 60 oxy
1-2 40 oxy
1 R oxy (really tiny)
8 AC4's
2 AC3's
2 B Acetylene
1 MC Acetylene
1 S C25
1 50lb C02 (actually I have 2 right now since mines nearly empty)
6 20lb CO2 (mostly for the local food places but some buy them for MIG)
6 40 Nitrogen for the local refrigeration guys

I get restocked every 2 weeks and it's very unpredictable what will be sold. However this year I've been down to between 2 and none K oxy several times in the two weeks.

[SundownIII]

Irish,

Actually, there is a substantial difference in the two high end flowmeters that Smith offers.

The Argon/CO2 flowmeter regulator (don't have the part numbers handy) is set to provide gas at 80PSI. The Smith Argon/CO2/Helium (multifuel flowmeter) delivers gas at 50PSI. This is the flowmeter (flowmeter alone) that I use with the Thermco. If you look closely, you'll see that I added an external gauge to monitor the delivery pressure.

I have not used the long post mix hose to the Smith mixers. They're so small/light I set them on the machine and use a short delivery hose. The gas is fed to the Smith mixers via standard double hose welding hoses at about 100 PSI pressure.

You're going to really like that Optima. Use mine on the XMT 304 with the S714D (basically the same feeder as the S74D) feeder, the 30A, and a recently added 12RC. Cat's meow for out of position welds.

[irish fixit]

Irish,

Actually, there is a substantial difference in the two high end flowmeters that Smith offers.

The Argon/CO2 flowmeter regulator (don't have the part numbers handy) is set to provide gas at 80PSI. The Smith Argon/CO2/Helium (multifuel flowmeter) delivers gas at 50PSI. This is the flowmeter (flowmeter alone) that I use with the Thermco. If you look closely, you'll see that I added an external gauge to monitor the delivery pressure.

Yep. I didn't see you stating it being multi gas till after I had posted. Sorry

I have not used the long post mix hose to the Smith mixers. They're so small/light I set them on the machine and use a short delivery hose. The gas is fed to the Smith mixers via standard double hose welding hoses at about 100 PSI pressure.


Ok. I was just wondering.

You're going to really like that Optima. Use mine on the XMT 304 with the S714D (basically the same feeder as the S74D) feeder, the 30A, and a recently added 12RC. Cat's meow for out of position welds.

That's my hope. That's the exact reason that's spurred all the recent upgrades. It's sure been a pretty thorough upgrade this time.

Thanks

[BruceTS]

Impressive set-up Irish.....

SundownIII, I've seen several of your threads on your mixers and have been pondering for a while to get one. Well this thread inspired me to take another look on eBay and what did I find? I scored on a Thermco Gas Mixer 0-750 SCPH Argon/CO2 for $400 and there's 2 Smith mixers with no pics also currently up for grabs for $200 each. Couldn't decide which set-up to go with, but at that price I had to grab it. I've been wanting to try spray transfer for quite some time now.

[irish fixit]

Thanks. I was doing some of the labeling for calibrating the tubes Sun night after our discussion on this and noticed that I'm going to have to add another meter to the unit. The CO2 tube that's in there will not read low enough to do a 2% mix at a total of 20cfh. I'm going to have to add another small tube just for the mix. I want to leave the big tube for the rare case that I want 100% CO2 (I've got a roll of dual shield that calls for that).

Nice score on the Thermoco Bruce. Way to go. At the rate I'm going I'll easily have that much into my setup. I'm hoping that mine will be more versatile in the long run but that remains to be seen. (fingers crossed).

[irish fixit]

Houston there be mixing going on

Well the funny farm finally let me out again. (It's been a really long week).

After several false starts and a couple of changes I finally got it going. I'm sure there will have to be a little fine tuning here and there and I've still got to get the TIG reel set up but here it is.

As you can see in the last pic I had to try it out a little. Definitely got to do some more playing to figure out all the settings on the Optima.

[con_fuse9]

Didn't see this thread till now.

I picked up a used Smith Argon/CO2 mixer. Regulators should be coming in today.

I want to mix, not pure CO2, but C25 with the Argon. Smith suggest that the density or C25 is pretty close to the density of CO2 (and argon for that matter). Smith of course doesn't have any calibration for that. According to Smith the internals on all the mixers are the same (at least same part number). Its all calibration - which may include a different dial on the face of the mixer. I'm not worried about calibrating the flow right now.

How can I test the mix calibration? The gas suppliers around here (Maryland/Washington DC) only seem to be able to mix and/or test high pressure bottles.

I was thinking about making my own thermal test setup. Fill a 1 liter coke bottle with the mix gas, heat it under a heat lamp, and see how much the temperature changes after 10 minutes. Compare pure argon, pure CO2 (I could use the rest on kegorator), vs. C25 vs C10 vs. any mix I dial in.

Thoughts?

[SundownIII]

BruceTS,

Missed your post before.

You got a GREAT deal on the Thermco unit. I'm sure you'll be happy with it.


Con-Fuse,

My brother-in-law works for the local natural gas delivery company. They've got sensors/analyzers (spectrum analyzer) wihich, I suspect, will detect about any gas known to man. This is not "hobby stuff" and I'm sure they cost more than I've probably got tied up in welding equipment.:dizzy:

Thankfully, I didn't have to buy it, just got to use it.:D

[irish fixit]

I asked my friend who runs the local gas company and he doesn't have a meter for CO2 only for CO. However he is pretty sure that the local gas analysis company can test for it. I just have to get a sample bottle from them to fill up. They normally test the contents of the natural gas produced in the area (this is natural gas country) for the various producers we have. I don't think it costs a lot to have done.

I've not updated this thread lately primarily because I'm still trying the system out. However here is what I have managed so far.

One little problem I'm having is with my check valves. At normal flow rated they like to bounce. While I don't think this affects it much it is slightly irritating from a noise stand point. But it does tell me when there's flow going on.

I have managed to play with the mix some and do a little testing. One evening I hooked it up to my MM252 which I normally keep hooked to a bottle of C25 and it currently has .030" wire in it. I started with a mix I was pretty sure was close to C25 and I couldn't tell much difference in the welds except for the surge coming out at the beginning. The MM252 is worse about the surge than the suitcase. I'm pretty sure that's mostly because it doesn't have the extra filter screen fitting that the suitcases have on them. If I added a orifice or flow control of some form it would be fine.

Anyway on with the test. I started thinning out the CO2 incrementally while keeping the same welder settings to see the effects on the weld. I didn't notice a lot of change till I got near what I calculate as 10% CO2. At that point the weld actually acted a little hotter to me though part of that may of been the work piece heating up. Once I started going lower than that I started to see signs of it trying to go into spray mode. The arc became pretty unusable when I got down around 2% CO2 calculated.

At that point I backed up to around 8-10% CO2 and started playing with the settings on the welder. I was able to get into full spray mode with the .030" wire but I don't remember the welder settings. I played with it some for a while and then went back to the C25 mix. I played with the welder settings some more trying to get a feel for it. Now I've had that welder for over 1 1/2 years now and never got around to playing with the settings before. I'd been pretty happy with the way it welded at the factory settings except for the 1/4" setting with .035 wire which is really in globular territory voltage wise so I put it down to that. Anyway I found that with the .030" wire there was a pretty wide range up on the wire speed available before it started stubbing.

Anyway I can't say that I learned anything definitive from the test but I did learn a few new things about the welder and got a better feel for it and learned that I need to do some more playing.

Now with the XMT304 and Optima I've done some playing and work with it as well. I'm still working on getting a full handle on the pulser but I have managed to make some decent beads with it. I do have to work on the out of position settings though. I'm not always happy with them. I hope having the digital readout on my new wire feeder will help me get that under control.

I have used it both in full spray mode without pulser and in short circuit mode with success. On the spray mode it did take a little bit to fine tune but I'm used to that from the old Dimension 400. Friday I did some short circuit work with it after resetting the gas to about C25 and I can say that I'm real happy with the way that worked out. I was running roughly 375ipm (the old wire feeder is kind of vague) and 22 or so volts with the .035" wire I have in that welder. The welds came out great with no problems at all. Again I'm hoping to be able to come up with a chart using the new wire feeder.

I've not managed to get any welding grade helium yet so I've not tested that part of the mixer. I'm about the only one my LWS has that does much TIG thus they've not really got a lot of the stuff for it. They're supposed to be checking for me. I've quit handling the balloon grade helium myself so I couldn't test it to see if it had any 02 in it (my main user still owes me for the last bottle so I don't care if I keep it anymore).

So that's where I stand on it at the moment. So far it seems to work well overall.