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  • Oxygen-Hydrogen Gas Welding

    As I've been accruing equipment during covid bargain days instead of shaping metal, I was able to purchase a Meco Midget, a spare OxWeld gas saver and some tips for my favorite old Concoa 750. Using the right tip sure makes gas welding aluminum easier.... No matter, reading about Bill Tromblay's move into Oxy-Hydrogen welding seems like a more practical avenue to pursue- particularly for the reduced flux usage & resulting reduction of clean-up issues inside closed vessel work like tanks or sculpture.

    This thread will help document what I'm doing, from the very beginning, in hopes that it may help others if they choose to go the same route. Bill has posted great information here and directly shared more good information with me. If he's ok with it, I would like to see his posts about the subject also cc'd here. MM/Matt has also posted some related information, including reference to a fire brick method for lighting/adjusting the flame. Got anything good about OH welding? Please post it or links here so it's not lost inside some other thread where you can never find it when you actually need it.


    In full disclosure- I have never done oxy-hyd welding. I and NOT a professional, certified, whatever welder. I just like doing it. so If what I post needs correction, especially in terms of actual safety concerns, post a correction if you have better facts.

    Basic equipment.

    Regulators.

    Bill referred me to a trusted rebuilder who could meet my need for regulators that would operate properly in the 1psi range as used for oxy-hyd welding. He recommended that I source a pair of dual stage regulators.

    Quick basic regulator explanation. Tanks will be at very high pressure as filled- 300psi. A single stage regulator must step that pressure down to a usable range in one step. This is difficult to do while maintaining a consistent torch delivery pressure. This is why your flame may change as pressure drops in your tanks while using a single stage regulators. A dual stage regulator will lower that 300psi to perhaps 100psi in the first stage (which is typically preset at build/rebuild and not adjusted) and the next step from 100psi to torch pressure will be adjusted by the operator. Thus, a dual stage regulator can provide better service for consistent low pressure delivery to torch. If you're looking at them, a single stage regulator will typically be flat on the back while a dual stage regulator will have a large hump with a hex head.

    The rebuilder recommended that I source a pair of Victor VTS250 dual stage regulators. Some online posts say a larger diameter diaphragm- typically the full professional/industrial versions- is more sensitive to adjustment and is better to have. So I asked him about using VTS450 regulators (approx twice the diameter) instead of a 250. He said for the low psi I plan to use, he had found it was easier to achieve with the 250 versions and their lighter springs. The 450 springs would need actual physical modification to get into the 1 psi range, not impossible but not as easy as using a 250.

    Victor VTS regulators have a letter suffix, such as VTS250A. The letter denotes the original pressure delivery range and corresponding values on the delivery pressure gauge as equipped by Victor. Here, "A" means it's good for 2psi -15psi. The higher the letter, the higher the pressure and the larger numbers on the pressure gauge. There are charts posted online showing these specs. He said this was not an issue for a custom rebuild that he would suit to my needs, but if you're trying to use regulators as you find them you may prefer to buy a low letter version.

    The reason he recommended Victor VTS250 or 450 regulators is based upon availability of rebuild kits and parts. He said other two stage regulators could be used, but only if we could get the necessary parts. Like so much other old gas welding torches now out of production & obsolete, regulators are no different. It's something to consider when making your purchases. Make sure regulators you are considering can be rebuilt before spending money.

    I did ask him about cross contamination- using soft parts with Hydrogen that had previously had acetylene or propane exposure. He said in his career rebuilding equipment that he had never quarantined gear and had never had a problem mixing and matching fuels. He warned me against mixing oxygen and fuel components but otherwise said I should be ok to use fuel equipment with fuel gases as needed. If this is wrong, please post better info....

    Today I ordered a pair of VTS-250 regulators. Cost on ebay was approx $42.00 and $49.00 respectively including initial shipping of each directly to him in Arizona. As I have more information, I'll post it.
    Last edited by cliffrod; 16-04-21, 11:23 PM.

  • #2
    Great piece....๐Ÿ˜‰
    https://www.precisionpanelcraft.co.uk/

    Comment


    • #3
      These are posts from Bill Tromblay including info about Oxygen/Hydrogen from another thread here. There's good info including about where to get low pressure 0-15psi guages-

      Originally posted by Bill Tromblay View Post
      Hi,

      I have the Henrob, and it is ok. The aluminum handles make it heavy and the pistol grip works great for a pistol, but not so much for welding. I use mine for Oxy/Acetylene welding and it works fine, but I prefer the Meco Midget.

      Setting of pressures to your cheek and my year and half learning curve.... ๐Ÿ˜ฉ Short back story on my knowledge. I received certification for Aerospace welding with the use of Tig, steel and aluminum. I think I weld relatively Ok. Others can weld nicer, but I get the job done that is Airworthy. I think I understand the concept of gluing two pieces of material together with a weld. So, I decided to learn something new and go the Oxy/Hydrogen gas welding route as used by the aircraft company's of WW2. I bought the all the stuff new, gauges, hoses, Meco Torch, flux and on and on. I ordered the videos and every book I could find on the subject and sat down with a bowl of pop corn and watched away. "The trick" you don't need to use the gauges, turn up the regulators until you feel it on your cheek and go as described above. Great, off to the races.... The reg's that I bought had 0-150psi gauges installed, as you turn up the pressure and feel it on my cheek, it wouldn't move the needle off the peg, (but that is ok, because I have this trick).

      Unknown to me at the time. When I would weld, a scab of aluminum would form over the weld (like you see on a casserole or on brown gravy) and the heat was extremely hot ( i'm going down in tip sizes from the recommended sizes). I would weld so fast, I had to use 1/8" dia rod, because I couldn't feed fast enough. The weld bead would look beautiful on the bottom, but the top would look like grains of salt,, stuck in the weld. No matter what I did, I couldn't make it go away. Leak checks, filters, different operator, different gas, same result. I consulted with above and others... The issue was "me" or "bad technique" or "what do you expect" or "fix your equipment (even though it was bought new from a guy in California)". But I didn't give up and I tried and tried and tried, varied my techniques, and equipment and no matter what I did, I would get the exact same result. One thing was for sure, no matter what I did or varied, I would get the exact same result (guess I had more skill than I thought).

      Then..... One Saturday morning I log into Facebook and a guy by the name of Solice metal works is Oxy/Hydrogen gas welding some aluminum fenders together with the most beautiful work and beads you can imagine. I quick welded a test bead, still crap... Take a picture send it to him in a message and wait for a response. He writes back 5 min later with one question "what pressure are you running at??" Hmmm...??? I removed the 0-150psi gauge and installed a 0-15psi gauge that I had laying around. Opened the regulators and the torch and looked at the pressure. Alcoa, Reynolds Aluminum, Kent Whites booklets and videos, WW2 welding manuals all state that Oxy/Hydrogen welding should be set at 2psi Oxygen, 1psi Hydrogen. My highly calibrated cheek is set at 10 psi.... After wetting my pants, I turned down the both regulators to 2psi and 1psi respectively and proceeded to weld the most perfect, beautiful, wonderful, joyful weld that I have ever seen... Wetting my pants again on the process...

      The scab and crystallizing of the weld pool was caused by oxidizing the living F#^& out of the weld, because the pressures were so high. It took a year and a half to finally figure out the problem and was by far one of the hardest things I ever learned. I have since bought overhauled two stage regulators with low tension diaphragm springs and low pressure gauges. The repair shop specially set them up for low pressure work.

      Tricks and short cuts are great, but only once you learn the fundamentals. Every one says you have to move when you gas weld or you will blow holes, not true with the right equipment. I can gas weld .025" thick 3003 with no holes. Holes can still happen, but nothing like you see in the training videos that are out there.

      Hope it helps someone save the time I invested, by some not so go advice.

      Bill
      Originally posted by Bill Tromblay View Post
      Hi,

      With the hydrogen unknowingly at 10 psi, I was running the oxygen (unknowingly) at the same pressure. The Oxygen needed to be that high, to create a cone. So even with high pressure, you can mix the gas to change the cone length, just as you can at 1 psi. The one thing i noticed with the higher pressure, you could go from a cold flame, to brutally hot, with a slight bump of the control valves on the torch. You had no fidelity with the controls. With the pressure now set correctly, I have a lot of control. One way I thought of explaining it, would be to turn up the TIG welder to full amperage than weld with it. Can you do it? Sure, but it isn't easy and will look bad.

      I saw a picture today on-line of a Oxy/Acetylene gas weld on .063" 3003 aluminum and they had it set at 4 psi Oxygen and 4 psi Acetylene and their results had the same appearance as my welds. You can see the "salt crystal grains" appearance running thru the top of the weld and the bottom looks fine. As metal shaper's, most guys dont care about the appearance, because you grind the weld off or planish it into the surface. On most aircraft components, the welds were left visible, and caused my concern to solve the problem.

      B
      Originally posted by Bill Tromblay View Post
      Hi Cliff,
      Yes, oxide has a higher surface tension than non-oxidized aluminum, this is due to a higher melt temperature of aluminum oxide, then the base material. Flux is chemically cleaning the surface of oxide and de-gassing the weld pool. Because of the oxide issue, it is always good to wire brush or scotch brite the weld area before you start on both side, in both gas and tig welding.

      If you search McMaster/Carr, they sell 0-15 psi oxygen approved gauges that you could use to replace your 0-150 psi units. Only use Oxygen approved gauges on the oxygen side due to a danger of mixing oil in a O2 system. If you go the low gauge route, every day when you are done welding, be sure to back the regulators off, to eliminate a surge when you open the tank the next time and damage the new gauges. Good practice with any regulator.

      I can bring the hydrogen to Jim Hury's event, if you are interested in giving it a try.

      Hope it helps and you are doing well.

      Bill
      Final cut & paste is my cheap workaround to set a low psi with a common vacuum/fuel pressure gauge using whatever regulators you have available. As mentioned, if using single stage regulators it is likely that your delivery psi and flame will change as the pressure in your tank(s) diminish. That has likely been part of my problem with inconsistency issues in the past.

      Originally posted by cliffrod View Post
      Charlie- here's a couple of pics. It's not my idea but works well for me

      Click image for larger version Name:	image.jpeg Views:	0 Size:	1.42 MB ID:	2681

      Click image for larger version  Name:	image_976.jpg Views:	248 Size:	1.24 MB ID:	2680


      It's much easier to read this plain engine vacuum/fuel pressure gauge that only ranges up to 7 psi than the much less definitive gauges, especially the oxygen. Slip the hose over the torch tip, open the respective valve on the torch and adjust the regulator by this pressure gauge instead of gauge on the regulator. Then close torch valve, disconnect hose to relieve pressures and repeat with the other tank. At 3-4 psi, the standard oxygen regulator gauge barely moves if it moves at all.

      But when the line pressures are set accurately like this, there's even fewer reasons for a bad weld. And i still have undesireable welds. It couldn't be the operator, could it?...
      Last edited by cliffrod; 19-04-21, 04:20 PM. Reason: lots of copy & paste

      Comment


      • #4
        Rick at Marshall's Torch Service called to say my regulators were rebuilt (approx 1 day turnaround after receipt) and ready to ship to me. They needed a full rebuild and are now equipped to operate at a maximum 6psi. He said this should make them easy to accurately adjust to 1psi or 2 psi for my use. With his permission, I have posted his full contact information in the business classifieds section. Link to ad- https://ce8df029be3e-004671.vbulleti...rvice#post6254

        Rick Marshall
        Marshall's Torch Service LLC
        12819 N 39th Drive
        Phoenix, Arizona 85029
        (623) 980-6726
        torchmastered at yahoo dot com

        While waiting for the regulators to arrive, I've been reading what I have and what I could find. Not much in the books here, except for page 66 in Aircraft Welding by L.S Elzea with a couple of paragraphs and a chart by ALCOA comparing oxyhydrogen to oxycetylene. It's a great book to have regarding gas welding in general, but don't expect lots of content regarding OH welding. The chart is good, covering metal thickness, diameter of tip orifice and psi for both oxyhydrogen and oxyacetylene. I've not found it elsewhere yet. Looks like its feasible to gas weld up to 3/8' thick aluminum with 5psi oxygen and 3 psi hydrogen. It looks like there's a misprint regarding 1/2" thick (also listed as 3/8" thick) requiring 8psi oxygen and 6psi hydrogen.

        The other best concise information I've found so far is this link- http://www.redbackaviation.com/how-t...ding-aluminum/ This link has a very good description of the fire brick method used to adjust your flame. Lighting the torch is discussed, along with the "invisible" flame- both things I've heard about and wondered how to address. Apparently the flame is not invisible to the naked eye. It is invisible when viewed through welding goggles.

        Other interesting information found includes the explanation of why Hydrogen was used in lieu of Acetylene in the first place. Long story short, it was out of necessity as acetylene was being rationed for wartime use. Unlike acetylene, hydrogen could be readily produced by an on-site generator without special supplies. How that was/is done is probably similar to what I did in science class in high school, using a proper solution with water and electricity to break apart molecular bonds in water iirc and produce Hydrogen gas. We captured a small amount of H gas and then stood back as the teacher ignited it, producing a loud "pop" Don't think they teach & demonstrate those kinds of things in high school anymore.... Apparently, using hydrogen as a welding fuel was simply a convenient workaround. Whether the benefits of OH welding were preferred at first or realized later, I don't know.

        Another article discussed avoiding cross contamination of other fuels with hydrogen with hoses. Still not sure. Since I'm planning to buy new regular hoses, spark arrestors and check valves for this kit anyways, I will probably buy another set of Kent White's lightweight short hoses and not be the guy who blows up trying to save $50.00......
        Last edited by cliffrod; 23-04-21, 02:35 PM.

        Comment


        • #5
          Great information Cliffy!

          I am glad that you are taking safety seriously; hoses are so cheap it is not worth saving pennies,

          Cheers Charlie

          Comment


          • #6
            Originally posted by Chazza View Post
            Great information Cliffy!

            I am glad that you are taking safety seriously; hoses are so cheap it is not worth saving pennies,

            Cheers Charlie
            Thanks, Charlie. It's surprising that there is such a wide range of information, including either a lack of or very contradictory specific details, on the topic. That's one reason why I hoped a thread about gearing up and actually doing it might be beneficial to others here.

            For examples:

            The Aircraft Welding page & specific chart noted above recommends 1psi hydrogen and 2 psi oxygen for the typical thicknesses of metal we shape. I like old books and such charts that were contemporary to the actual work, because the information typically seems to be more accurate in my experience. After that, the information gets recycled- sometimes good, sometimes bad.... The recommendation for 10psi as a starting point for both Hydrogen and Oxygen in the linked internet article as a starting point, which is literally off that chart and inconsistent in terms of using different pressure (up to a ratio of 1:2) of hydrogen vs oxygen. Bill Tromblay posted about inclusion problems at high psi operations. He also had trouble calibrating his cheek. He finally found a better way and produced Bill-quality results at low psi as recommended by another welder, who recommended the same pressures as that old chart recommended. Anytime I can produce Bill-quality results in general, I'll be very happy.

            Rick the Regulator Rebuilder said he had no issues regarding contamination between other fuels and hydrogen. Others (and I realize anyone can post anything on the internet.. myself included) say it's a problem. My lightweight lead hoses have had fuel gas in them for maybe 5 minutes. Is that long enough to cause a problem? Is it something that will even cause a problem at all? All I know is that I've learned is that in general, asking the guy who is selling (in this case) hoses if I need to buy more of his hoses usually produces a very predictable response regardless of the facts..... So I'll keep the hoses I already have for oxy/acetylene crs use and get a separate set dedicated for oxy/hydrogen aluminum use.

            At least the linked article talks about lighting the torch and the fire brick method used to adjust the flame. Very cool.

            Comment


            • #7
              Hi,

              Good information so far. I never found it written down in regards to cross mixing the gases and have only heard it from the guy selling the hoses. My used gas saver was used with a acetylene torch and I'm still here๐Ÿ˜ With that being said I use separate equipment and prevent cross contamination. My gas saver had not been used in many years before my purchase so the chance of stay Acetylene was very low. My biggest concern here at the shop is oil mixed with oxygen, which is an explosive combination.

              I recommend an external light source while welding. Because of the clear flame, you have nothing to light up the part while welding and with welding goggles on, it gets quiet dark. Remember, if you can see while welding, your welds will look like it.

              Once you are all set to start, let me know and I can help with the learning curve. There are many little things that can make or break a good weld.

              Remember your wise words, "pick your master wisely" there is some not so good info floating around on the inner webs....

              B

              Comment


              • #8
                Good work Bill and Cliffy, I appreciate people who seek the truth and share it with others.

                On the subject of gas explosions with welding equipment, I remember reading about this:

                Some years ago, the Western Australian safety authority called Worksafe, published their findings about an oxygen regulator explosion that had badly injured a welder in the face; this would have been in in the 1990's when the internet was new. Examination of the destroyed regulator, found that the rubber diaphragm had been replaced with a new cheaper version, made somewhere overseas. The rubber was of poor quality and contained some free sulphur on the surface.

                Compounding this nasty mixture of elements, was the welder's poor operating technique. Instead of purging the hoses and releasing pressure on the diaphragm when closing the plant down, he did what I have seen some of my friends do. He closed the main-valve on the cylinders and went home. First thing in the morning he opened the main-valve, which allowed a rush of oxygen into the regulator at high-velocity, which was enough to ignite the sulphur.

                Who knows what contaminants exist in old hoses!

                Moral of the story; in addition to choosing your master wisely, choose your equipment and work-practise wisely.

                Cheers Charlie

                Comment


                • #9
                  Originally posted by Bill Tromblay View Post
                  Hi,

                  Good information so far. I never found it written down in regards to cross mixing the gases and have only heard it from the guy selling the hoses. My used gas saver was used with a acetylene torch and I'm still here๐Ÿ˜ With that being said I use separate equipment and prevent cross contamination. My gas saver had not been used in many years before my purchase so the chance of stay Acetylene was very low. My biggest concern here at the shop is oil mixed with oxygen, which is an explosive combination.

                  I recommend an external light source while welding. Because of the clear flame, you have nothing to light up the part while welding and with welding goggles on, it gets quiet dark. Remember, if you can see while welding, your welds will look like it.

                  Once you are all set to start, let me know and I can help with the learning curve. There are many little things that can make or break a good weld.

                  Remember your wise words, "pick your master wisely" there is some not so good info floating around on the inner webs....

                  B
                  Right now I trust you, Bill. You're doing it and I have a lot of respect for what I've seen you do as a general standard. I have no doubts you're doing the same level of research and work in this pursuit. This internet has more value in some areas than in others. I would like to be welding with hydrogen reasonably soon, before Jim's event so I can have more productive time with you about it.

                  I knew your posts talked about using torches that had been used with other fuels but not rebuilt before using them with hydrogen. This meco and gas saver are both used, so I didn't plan to rebuild them either. Setting up a separate set of hoses for a dedicated rig makes more sense, anyways. no matter how much OH welding I do, I still have lots of regular brazing with my oxy/acetylene rig to do.

                  When you say external light source, are you talking about a lamp of some kind or actual external natural light? What are you using? I just redid the lighting in my shops and it's much brighter now. My regular welding station is at a bench in front of a window for additional lighting.

                  And I do ALWAYS release my regulators completely and purge my hoses & gas saver, Charlie. It's an easy habit to learn and keep. no matter how skilled or not I am as a welder. Rick mentioned the concerns he has about which brand regulators for which he can source quality parts for rebuilding. Even if another brand regulator is possible to rebuild, he knows what he trusts for parts and sources.

                  Lots of good info to have written down for others to consider. Thanks, guys.

                  Comment


                  • #10
                    Regulators arrived from Rick. They look like new. Rick said they are good for use up to approx 6psi. His charge was $175.00 including complete rebuild and shipping to me for the pair, so total cost for me was $266.00 for both regulators. Rick's rebuild included converting the tank fitting on the fuel/Hydrogen regulator to a left thread female to fit the left hand male fitting on the Hydrogen tank. His turnaround was great. He received them on Monday and called me on Wednesday evening to say they were ready to ship. Great guy, great service.

                    After understanding I could buy a medium-sized tank outright for exchange/refill to avoid an ongoing lease charge of a full-sized tank, I was told the local welding supply house only had full-size tanks of hydrogen. And they were all puzzled if not averse to the idea of welding with Hydrogen, so were not particularly receptive to the idea.

                    Typically, small (20cf-40cf) and medium (80cf-120cf) sized tanks are purchased outright and then exchanged for a full tank upon purchase/request. No issues unless the tank is out of certification, which may require an additional fee. This supply house currently charges $40.00 iirc for a 40cu tank that's out of date. Privately owned fullsize tanks must be inspected before they are refilled. If the tank doesn't pass inspection, which usually requires days/weeks because it is not done onsite, it is discarded with no reimbursement. So these larger tanks are normally leased. This time I got a tank of full size Hydrogen tank with a lifetime lease (one time fee) vs a monthly or annual lease. Cost was approx $280.00 with future refills contracted at $48.00/fill. Think I'm going to add another larger oxygen tank to this rig. I only have two 40cf Oxygen tanks now and don't like running out of oxygen or fuel gas midway through a Saturday morning, which is always when it seems to happen...

                    Still need a few more pieces and time, probably next month, before I'm welding.

                    Comment


                    • #11
                      More money spent today. Now the majority of my Oxy-Hydrogen welding kit is in place. A quick run-down on $$ actually spent-
                      • Meco Torch and 3 tips- used, via ebay- $ 150.00 (new, approx $200 plus shipping with same 3 tips)
                      • Kent White lightweight hose, new $ 50.00
                      • TM2000 Welding lens, bought new 20 yrs ago $ ?? (new, approx $200 now plus shipping)
                      • OxWeld Gas saver, used via FB MP $ 40.00 (new, approx $200.00- $300.00)
                      • Primary welding hose- new $ 40.00
                      • Regulators, Purchase, Both used via Ebay $ 91.00 (Victor VTS 250C $42.00 and Victor VTS 250D $49.00)
                      • Regulators, rebuild & shipping $ 175.00 (Includes full new rebuilt kits, new gauges and fitting conversion to left hand female for Hydrogen tank)
                      • Welding Cylinder Truck- used via Craigslist $ 30.00 (new, approx $250.00-$300.00)
                      • Hydrogen, 214CF tank, lifetime lease $ 285.00 (refills $48.00)
                      • Oxygen, 138cf tank lifetime lease $ 236.00 (refills $21.00)
                      • Y Connector for Oxygen $ 30.00 (to split Oxygen line for Oxy/Acetylene welding)
                      Total to date- $1,127.00

                      Buying more or all items new, I can easily see a $1,500.00-$1,700.00 or greater expenditure for a similar kit. Didn't plan to spend this much, but it's a slippery slope. This may help others here plan their budget. I could have used my small 40cf oxygen tanks, but have wanted to upgrade for years. About the only unavoidable expenses was TM2000 lens ($200) and the large Hydrogen tank ($285). Depending upon what you have, the purpose-built low PSI regulators are probably more necessary than optional (approx $250-$300). That's approx $735.00-$750.00. With time and trading or using different gear already on hand, the other costs could be managed.

                      I did purchase (and return) new spark arrestors to install in-line, only to be advised that they would be ineffective at these low pressures. Because of the min pressure needed to operate the valves in the arrestors, pressure will build & then release causing undesirable fluctuation in the torch flame. The most PC way to state this came from one of the big names, who said "some people choose not to use them...." This is probably another reason why my oxy-acetylene flame seemed to fluctuate at very low PSI when welding thin, which is further compounded by single stage regulators.

                      Shop time still must wait. I will order a couple of larger tips for this Meco, so will spend a little more. In a perfect world, the extra parts will arrive by the time things slow down around here.
                      Last edited by cliffrod; 13-05-21, 07:16 PM. Reason: format

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