learning to TIG weld

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I'm attempting to learn how to TIG weld and hope to tig weld up a Stainless Steel Egli-Vincent frame later on this year.So far I've been practising on a friend's Lincoln 185 amp AC/DC machine.Started out burning lots of holes but things have improved a bit. I have about 6 hrs in now.I'd appreciate any advice or tips offered.Thanks in advance.Here is a weld from today's practise session. Attached Images
Reply:Not bad for only six hours. Whats the back look like? When you post a pic of your work, it's usually a good idea to include the vital statistics. Amps, material thickness, tungsten diameter, filler type and diameter, gas flow settings, and any other vital info you can think of. Helps to understand what we're looking at. Also, it's generally a good idea to post your location. You never know, you could be living next door to some one that could help you out.When it comes to vehicle frames, even a motorcycle, it good to have years of practice under your belt. They are subject to lots of vibration and other stresses, and corrosive elements. Keep in mind that at least one persons life (possibly more) hangs on your welds. Just something to consider. Not saying you can't do it. Just know that you're liable for your work. Anyhoo, welcome to the forum.
Reply:My welding setup was electrode negative, no pulse, 70 amps, red 3/32" tungsten, 7/16 cup, .065  309 ss filler rod, argon @ 10cfm.  The material is 1/8" thick 304 SS.The back side of this weld is hidden because I did a pass on the back as well. Penetration was good though.I'm in Langley BC.I've stick welded for many years.Stainless stick welds so nicely that I was tempted to stick weld this frame together.  Common wisdom indicates TIG is much better suited to the thin wall construction(.045), so I thought I would put some time in with the TIG setup.Already I like the fact that there is no weld spatter to contend with. Also, the TIG is nice for stopping and starting. I think with some practice the stop start points will not even be visible. This is going to be especially useful when welding the cope fits where two 7/8" dia pipes butt together.I've been trying some fillet welds as well, still a long way to go with those.Last edited by worntorn; 03-17-2010 at 01:25 AM.
Reply:Originally Posted by worntorn Also, the TIG is nice for stopping and starting. I think with some practice the stop start points will not even be visible.
Reply:Awesome man you will fall in love with it when you get it down!!
Reply:I forgot to mention befor. Since you're working on stainless steel, if you want to get complete penetration you're going to want some sort of back purge or something to keep the back side of the weld from sugaring.
Reply:Is the back purge needed for strength or just for cosmetics?  The back of the welds won't be visible on the frame I'm building.thanksGlen
Reply:Both. Sugaring looks like garbage, would want people to see that. Plus it's full of fisures and crevices, giving ample oportunity for stress fractures to begin. As for the metalurgy, oxieds are generally weeker than un-oxodize metal (can't think of any metal where the opposite would be true). There are several option to a back purge, a quick easy way to go is to just put a piece of copper on the back side of the weld. You may still get a little oxide, but not the sugaring effect.
Reply:A couple of weeks ago I gave up on driving over to my friend's shop in order to learn how to TIG weld. I could see that it is going to take many, many hours and it won't happen unless I have a tig welder in the shop here at my home.Since metal work is only a hobby for me, I went super cheap and bought a $299 Chinese 200 amp welder. This welder is one step up from the bottom in that it has HF no touch start.I fired it up last night with not much in the way of expectations. I was pleasantly surprised, right away I was laying down very nice beads with it on  flat welding. In fact these looked better than anything I had done with my friend's $3500 Lincoln. The machine seemed much easier to use than the Lincoln  somehow. This really shocked me since I haven't done any welding for a couple of weeks and expected to be a bit rusty(bad pun).Did some more welding with it today and realized that the test piece of tubing I grabbed yesterday was .080 wall, not the 065 wall that I was welding with the Lincoln.I did some welds on some 065 wall today and they weren't any better than those that I did two weeks ago with the Lincoln, but were no worse either.As far as ease of use/quality of weld, I can't really see much difference between the two machines at this point, although the Lincoln is AC DC whereas this is just a DC inverter machine. This machine has a bit smaller torch head which is nicer for the small stuff I'm doing. One other difference is that this inverter welder seems to work best a little lower settings than the Lincoln did. I can't imagine ever using the full 200 amps. For this .065 stainless I am setting it on 50 for butt welds whereas the Lincoln was right at about 60 amps. Everything on it looks a little chintzy  but it all works fine. When I get everything going right, the stack of dimes shows up, although they might only be pennies with a machine this low in cost. It will be interesting to see if it lasts. I suspect that if it makes it thru the first week or two it will be fine for years.I'll post some more pictures once I make a little progress.This is the only piece of Chinese machinery in my shop. All of my woodworking machines (about 40 tons or so of heavy iron) are American, Italian, German, Canadian or Japanese.I make my living with this stuff and do not want to work with low end machinery.I may regret this welder purchase, but at the moment it is looking like a remarkably good little machine for the money.Glen
Reply:Originally Posted by worntornA couple of weeks ago I gave up on driving over to my friend's shop in order to learn how to TIG weld. I could see that it is going to take many, many hours and it won't happen unless I have a tig welder in the shop here at my home.Since metal work is only a hobby for me, I went super cheap and bought a $299 Chinese 200 amp welder. This welder is one step up from the bottom in that it has HF no touch start.I fired it up last night with not much in the way of expectations. I was pleasantly surprised, right away I was laying down very nice beads with it on  flat welding. In fact these looked better than anything I had done with my friend's $3500 Lincoln. The machine seemed much easier to use than the Lincoln  somehow. This really shocked me since I haven't done any welding for a couple of weeks and expected to be a bit rusty(bad pun).Did some more welding with it today and realized that the test piece of tubing I grabbed yesterday was .080 wall, not the 065 wall that I was welding with the Lincoln.I did some welds on some 065 wall today and they weren't any better than those that I did two weeks ago with the Lincoln, but were no worse either.As far as ease of use/quality of weld, I can't really see much difference between the two machines at this point, although the Lincoln is AC DC whereas this is just a DC inverter machine. This machine has a bit smaller torch head which is nicer for the small stuff I'm doing. One other difference is that this inverter welder seems to work best a little lower settings than the Lincoln did. I can't imagine ever using the full 200 amps. For this .065 stainless I am setting it on 50 for butt welds whereas the Lincoln was right at about 60 amps. Everything on it looks a little chintzy  but it all works fine. When I get everything going right, the stack of dimes shows up, although they might only be pennies with a machine this low in cost. It will be interesting to see if it lasts. I suspect that if it makes it thru the first week or two it will be fine for years.I'll post some more pictures once I make a little progress.This is the only piece of Chinese machinery in my shop. All of my woodworking machines (about 40 tons or so of heavy iron) are American, Italian, German, Canadian or Japanese.I make my living with this stuff and do not want to work with low end machinery.I may regret this welder purchase, but at the moment it is looking like a remarkably good little machine for the money.Glen
Reply:Dumb question but why stainless? I thought Egli used nickel plated steel frames on the Vincents? Have you taken all the material properties into consideration with this material change?
Reply:Worntorn,Post some more pics...we'd really like to see your progress.Glad to see the Chinese machine is working for you.  Check out Weldingtipsandtricks.com.  Jody (moderator) shows off a Chinese TIG machine (everlast) and demonstrates the various settings.  It helped me alot.After you get the DC sst/cs TIG down pat you might want to consider upgrading to an AC/DC machine and trying you hand at aluminum welding.  I bought a very used AC/DC machine back in Dec '09 and can't believe the results I've had.  Fillets on aluminum are still challenging but improving.  Butt welds on 1/8" aluminum are just about perfect - stack of dimes, great penetration, sometimes a crater at the end but getting better!  TIG welding is awesome.For the sugaring on sst, I've used Solar B flux.  About $40 a can which should last a lifetime.  Easy to use, stops the sugaring, helps prevent blow-thru and you don't need the plumbing/fixtrues required for back purging.I'll second what Grimm1 said about frame welding.  I don't mean to be preachy but please be careful.  Back in the late 60's, a friend of mine welded up a motorbike and went for a ride.  The front forks separated from the frame and he spent the rest of the day in the hospital...lucky that thing only went about 25 mph.Miller 211 w/ spool gunMiller Dynasty 200DXLongevity 60i IGBT plasmaO/A w/ crappy chinese torch/gaugesSouth Bend 10K latheGrizzly 4029 10x54 millGrizzly 7x12 hor bandsawangle grnders, bench grnder, bench belt sndr7.5 hp 80gal cmprsor
Reply:A couple of Eglis have been built in stainless over the years and this has worked fine.With stainless I like the fact that I can weld on a tab here or there at a later date without having to replate the frame. I should be able to just polish the weld.The Machine is HD brand. The main reason I chose it (aside from the low price) is that the other machines I looked at for this price had touch start rather than HF start. It could be that there are some other 200 amp machines out there with HF start for this price, but I didn't find any.I was down to a large Britbike show in San Jose last week and had a chance to look at welding on a couple of original Eglis. These bikes were put on the road in the late 1970s or early 80s and are used regularly today. The welds were quite poor in places, I think I can do a little better with enough practice.I'll look for the solar flux B, thanks for the tip.
Reply:Here is a butt weld along with a number of flat beads using a variety of settings, all on some .080 wall tubing. For the butt weld I  used a 3/32 tungsten and filler rod, 11 cfh argon, hard to tell what amps on this cheapie machine, my guess is around 75.Glen Attached Images
Reply:Here is the same buttweld again but first pass.The first photo was of the weld after making a second pass in order to end up with a convex weld. This weld is pretty much flush and flat. Attached Images
Reply:I've switched to practicing on the thin wall 1" square and having a lot of difficulty.So far this is the best I could manage. Leading up to this I bbq'd quite a few pieces and burned holes in others. This was done without filler rod  on the flat mitre weld , .045 309L filler on the fillet portion. Settings were about 50 amp for the flat no filler weld and about 60 amp for the fillet weld. After doing some reading on Welding Tips and Tricks I've upped the Argon flow to 15CFH.Tungsten is 1/16" Red.Cup is #7Tried a gas lens but the weld was at times so bright that I couldn't see the puddle, so I'm back to the regular setup. Attached Images
Reply:When asked about the "vital statistics", Worntorn said one setting was "electrode negative".  I was under the impression that was only used on aluminum.  Is that correct for ss?Hobby welder with MIG, stick and gas experience.  Just got a Miller 250 TIG that I hope to use with some degree of expertise someday
Reply:Direct Current Electrode Negative(DCEN) is correct for stainless steel,  mild steel and quite a few other metals.In order to weld Aluminium, Alternating Current is used, so this requires an AC/DC or straight AC welder.Glen
Reply:Perhaps I'm trying too hard or something as I seem to have regressed with this TIG welding. I can't seem to do nearly as nice of weld as when I started in with this Chinese welder.In frustration I tried the stick function of the machine with some 1/16 308 SS stick rods I have. I thought I could ease the frustration level a bit by making some decent looking welds. Right off I was impressed by how easy it is to run a good stick bead with this little welder.For this weld I had the machine set on just 30 amps.I'm tempted to stick weld the frame together, that's what I'm familiar with. At least that way I know it will hold together!One of the wellknown Egli Replica frame builders in the UK admitted that he stick welds the headstock to the tank then goes over the stick welds with the TIG torch to make it look as though it has been tig welded. I think this says something about his belief in the relative strength of the welds. The headstock has more stress on it than any other part of the frame, since when the front brake is applied hard the G force is so great. When the front brake is hit hard the headstock wants to peel out of the top spine/oiltank like a sardine can lid.As a minimum I'm thinking I will stick weld this connection.Any thoughts on stick vs TIG for thin wall tubing welds? Attached Images
Reply:I could not see any benifit of stick over TIG on thin wall tubing.Every process is capable of holding its own.  Joint prep is the key.
Reply:I see what you mean about joint prep Larry, especially with TIG. If the fit is good, then the TIG weld is good, however if there is a 1/64" gap then the edges just melt away from each other, leaving a hole.I suppose this is what I find easier about stick, with stick there is new filler material constantly being deposited so with a little bit of finesse a 1/64 gap in the fit is not a problem, it just fills in and disappears.
Reply:all welding is about the fitting when it comes to bikes and frames with tubing it better be rightif something was cracked on a frame i would take it apart and crop it back and re fit it if possibleStick is just as good as any process most frames are mig welded or pulse mig welded
Reply:What was the welding process used on the originals?
Reply:I have done a lot of mig and stick welding over the years, but not tig, so I was very impressed, and pleased, when the very second run I put down came out looking damn near as tidy as yours. Mine was on a flat butt joint, 2mm stainless sheet, so easier still, but I really got hooked on the idea of tig welding. The instructor was alos quite impressed and said it was a damn near perfect weld.m3 ds real
Reply:With the Egli frame it's hard to say what is original, there were an number of fabricators putting them together. Terry Prince is said to have built most of the first batch of frames for Fritz Egli.Terry also built some of the "Slater Eglis" which were Roger Slater's version of Fritz Egli's frame. I saw one of those last week at a Vincent Club member's house in California. It was brazed with quite large fillet welds. I'm not all that confident of brazing unless it is the tube in lug style connection. To me, just butting two pieces together then expect brass to hold by stiction is not the best way to go. On the other hand this frame has been in use for about 35 years old and looks to be just fine.The same fellow had a bare  Egli frame built some years ago by Colin Taylor. This frame had a variety of weld types on it and a little bit of brazing. About half of the welds had been ground smooth, the others were left in their natural state. I'm guessing that the welds that had been ground smooth were the ones that didn't look so nice.I'm finding out that with the Egli-Vincent frame, there are many variations on dimensions, fork angle (22degrees for the Slater Egli, 27degrees for most others) and construction methods.Peter, if an instructor looked at my pile of welds so far I don't think he would be too impressed. The ones I have taken the photos of and posted here are my best ones, so to put down a nice weld bead in TIG right off is quite an accomplishment.I really thought I would pick it up a little quicker, but at the moment it seems as though the more I practice the rougher it gets!I guess that is why I'm considering stickwelding it. I can do consistently decent stick welds so it is tempting to use this method instead of TIG. BTW the last photo was of a short bead of stick welding.Still struggling with the TIG but today I realized that I've been holding the torch incorrectly.I've been gripping it like a hammer rather than like a pencil. Looked at some more vids on weldingtipsand tricks and came to this realization.This change has made an improvement in the welds.Also, it would probably be worth investing in a wp9 torch for this small dimension thin material.The one I'm using is a wp 17.I tried the stick function a bit more, it really works well.One complaint is the amperage control knob- it is tiny and even the smallest movement changes the heat ouput quite a bit. This in itself is OK, but without a digital readout it is necessary to waste quite a bit of expensive rod just trying to get the amperage back to some earlier setting. A digital readout would be a big improvement and I see some of these cheap machines have them now. It would only be an improvement if it actually registered correctly and gave a repeatable setting.Here is a bit more stick welding on the .065 1" sqaure 304 SS with 316SS  1/16" rod and about 30 amps. Please feel free to critique these stick beads, I'm happy with them but welcome any thoughts about ways to improve. I think I will end up stick welding the main headstock connection to the spine and TIG welding the smaller 7/8" dia tube to tube connections. Attached Images
Reply:glad to hear yer new machine is workin ok for tyou. you will need that 200 amps if you get into aluminum
Reply:Its 200 amps, but no AC just DC so I will need another machine for aluminium.Right now I'm hoping to resurrect my old P+H 400 amp AC for aluminium. I need a footpedal and a few other bits for it.
Reply:I've purchased another machine, this one has a foot pedal. For now, I've gone back to laying beads on metal rather than joining items together.This  bead is done on a piece of .125 wall 304 SS. The rod was 1/16" 309L , argon flow 15cfh, cup is no. 7 with gas lens. I'm not sure of the amperage because the pedal on this machine goes 0-200 only, so it's a case of getting the puddle started then backing off the pedal a little as you go. The only way to know the amp setting is to leave the pedal down as when welding and  lift the torch at the end of the weld, then look at the digital readout.I'm guessing it was about 75 amps.Glen Attached Images
Reply:Tried welding two pieces together again. This is a crop of 1/8" wall 2" 304 SS square tubing that I had put some practice beads on. I cut it lengthwise and put the cut pieces together with a lap weld.I didn't use filler, same 1/16" 2% thoriated tungsten, 12cfh argon, gas lens and #7 cup.Amps unknown, just used the pedal to get the puddle about right.This weld came out silver with the rainbow hues here and there just like the big kids' SS tig welds have.I guess the secret to that is getting the weld done without too much heat.That can be difficult on the tiny scraps I've been practising on, might be different on a set of headers or some other large item. I'm hoping.please comment, negative or positive, I'm in the dark on this tig welding. (intended pun)Glen Attached Images
Reply:Still soldiering on with the tig practice. A friend had some crops of .065 wall  3" SS 304  left over from building a hotrod exhaust. I coped them out on the mill and have welded a couple of tee joints up. These joints are kind of hard to do, going from fillet to lap then back again.I know that the welds look a little undercut in the photos, but it is a bit of an shade effect, there is no undercutting. The welds are concave in the fillet sections though. Is this considered a flaw? Do I need more filler in order to keep the fillet flat or even convex?Filler rod is .045 309L SSGas is argon at 15cfhElectrode is 1/16th  2% thoriated tungstenGas lens and #6 cup Unsure of amps, using pedal maybe 50?thanksGlen Attached ImagesLast edited by worntorn; 05-09-2010 at 12:31 AM.
Reply:The profile on the fillet looks OK in the bottom photo, without practice and even using pulse I can make an awful mess with that very joint.Matt
Reply:The part where the weld is a lap weld( at the longest points on the coped piece) was a real struggle. The coped out piece is cut at a very acute angle here so it is like a knife edge.The best I could do was to concentrate the heat on the uncut piece and then briefly swing the electrodeand puddle into the knife edge. The knife edge wants to melt way back making the weld wider in this area at best, burning back and leaving a hole at worst.would it be better to grind the thin edge back till it has some thickness? I suppose this would change that part of the weld back to a fillet.Also, I found it necessary to stop and start the weld about ten times as I went around. I kept repositioning to keep the angle between electrode and work about right. Most of the welds were only an inch and a half long or so.Is this the way to do it, or do you try to move with the weld as you go round and keep the weld continuous?