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MIG Welds dont stick I am making a transition from flux-core wire feed to gas (CO2) wire feed and am having problems getting my welds to stick. Any advice or suggestions would be appreciated.My welder is a Canadian Tire MasterCraft (Campbell Hausfeld) 115 volt input with 4 output settings: two for 15A input and two higher ones for 20A input. Maximum output is 70 Amps DC.I was previously using ENI flux-core wire of 0.030 inch diameter. This worked well for steel of thickness of 18 gauge or greater nice on 1/8 inch stock. However, even at the lowest amperage setting I had to be very careful not to burn through on 20 to 22 gauge sheet usually I had to make a series of brief spot welds (stitching) then return to fill in the gaps.I am making the transition to gas. Because I dont weld a great deal, I want super portability, no rental fees and the fact that my son works in a paint-ball store, I opted to use carbon dioxide gas. I bought two 20 ounce CO2 capacity aluminum paint-ball tanks (10 cubic feet of CO2 in each) for ~$40. So, I am restricted to using CO2.As per the welder instructions, I reversed the DC polarity of the output (flux-core to MIG). I also changed to ENI 0.023 diameter inch solid MIG wire. Now my problem is the opposite of that I had with flux-core wire I seem to have difficulty getting fusion (burn-through is no longer the problem.).Clues?1 - I tried a Tee weld between two small plates of 22 gauge steel. I used my angle grinder to clean up all the pieces before hand. The horizontal plate was clamped to a metal table, the vertical plate was held in place by a magnet. During welding, I noticed a great deal more flying metal gobuls, sparks and splatter than I was used to with flux-core wire. Looking at the result, the weld appeared to stick on the vertical plate but not on the horizontal plate (maybe the heat was being sucked away by contact with the metal table?) No matter what the amperage setting I tried, the weld profile looked high and lumpy (round spheres or beads) and the weld was easily knocked apart with a chipping hammer. There were only a few spot of decent fusion along the length of the weld.2 I tried welding a mild-steel nut to the head of an 8-32 mild steel screw. No matter what output settings I used, the weld bead tended to be high in profile. It was easy to twist or chip the weld apart. Again, it looked like I had insuffient heat input and was only getting marginal fusion in a few spots. I appeared to be welding fine to the previous weld metal - making nice spherical lumps but the weld-metal lumps were not well fused to the base metal of either the nut or the screw.3 - I am keeping the welder nozzle close in to the weld so as not to lose my gas shield. However, I am feeling my way as to the amount of gas flow to use and the speed of wire-feed so those may be contributing factors. Perhaps someone can read these clues and say Ah ha, your problem is
.Any suggestions?Rick V
Reply:When you switched from flux to gas, did you switch the nozzle on the end of the gun to allow the gas to flow?What about the contact tip. Did you switch it from .030" to an .023"?If all of that is good, it sounds as if your wire speed is a bit fast. Does it pop and sputter while you're trying to weld? If it does, try turning the wire speed down. You also may have to adjust your "hand speed". Since the flux-core burns hotter, you can move your hand a lot faster...try slowing down and see if it helps.BTW, your gas flow should be around 12-15cfh.http://all-a-cart.comWelding Cart Kits and accessories
Reply:If your machine has voltage settings like hi med lo set to hi.Check wire feed speed with a tape measure and stop watch.Feed wire for 6 seconds and measure. Example 15 inches long = 150 ipm.or 3810 mm/minPolarity DC electrode positive DCEP or reverse Stick out should be 1/4 to 3/8 " or 6.4 to 8.6 mmgas flow 15-25 cfhIf the wire hits the plate w/o melting decrease wfs until the wire is melting off and you can't feel it touch the plate. Try supprting the project on something thinner to avoid the heat sink.Weldtek
Reply:It sounds to me like a lack of gas flow. If I ever forget to turn on the gas I usually get weld exactly like you describe.
Reply:are you getting any porosity in your welds when you grind them. What is your weld settings at including your gas flow?
Reply:the machine is "running in reverse"there was another thread about this awhile ago..seems when you switch from flux to gas the machine has to go "backwards" of what its set up for now..flux is neg..gas is pos. ground..or vice-versawichever whatever thats the problem......zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:On my MillerMatic 175 you have to change the polarity of the welder when you change between flux and solid wire. Basically swap the hot and neutral around.
Reply:Originally Posted by Rick VAs per the welder instructions, I reversed the DC polarity of the output (flux-core to MIG).
Reply:Unless he had it wrong to begin with... I seem to recall testing something and Flux Cored seemed to work okay both ways but Gas Sheilded was very picky...Its been a while since I played with that however.
Reply:Originally Posted by chicksdigwagonsUnless he had it wrong to begin with... I seem to recall testing something and Flux Cored seemed to work okay both ways but Gas Sheilded was very picky...Its been a while since I played with that however.
Reply:I've recently completed making a large metal security door, and had a couple of really bad days when attempting to weld with my 110v mig. Results were much like yours, even though I have previously been very satisfied with my welds. Now, the welder is again producing excellent beads and penetration. Wasn't using an extension cord in either case, which can result in situations like yours. The only thing that comes to mind, now that the machine is working again, is that, during the days that the weather was around 100 degrees, we had several fans running in the house that might have caused a voltage drop, which affected my mig. Or, people were running lots of air conditioners, which had the same effect. Sure glad my mig has got its buzz back.Have you pros ever heard of high electricity usage causing welding machines to lose their zip (or zap)?
Reply:Hi fellows - thanks for all the suggestions.Let me answer some of your questions:In respect to polarity, I followed the instructions in the manual to change the polarity. It is not really possible to make an error because one removes a cover plate with pointer that fits only one way over a small bus-bar assembly. To change polarity, one rotates the bus-bar assembly 90 degrees and replaces the cover plate - that now points 90 degrees to previously. The cover plate comes from the factory pointing to the upper right - "ELECTRODE NEGATIVE FLUX-CORE WIRE". After I rotated the bus-bar assembly through 90 degrees, the installed cover plate pointed to the upper left - "ELECTRODE POSITIVE MIG WIRE".ZTFab- When you switched from flux to gas, did you switch the nozzle on the end of the gun to allow the gas to flow?The nozzle is the same for both.On/off gas flow is controlled right at the gun trigger (O-ring gas valve); there is no electrical gas solenoid located inside the welder. (This might be useful if you wanted to use a foot switch to turn off AC input into the welder while you kept the gun trigger on to provide run-on gas flow.)- What about the contact tip. Did you switch it from .030" to an .023"?No, I didn't do that yet... I may have a little gas passing between the wire and the hole. However, the gas does not feed down the same tube as the wire and exits through about 8 holes located back of the contact tip.- Wire SpeedI didn't know - see measurements and results below.- BTW, your gas flow should be around 12-15cfh. I had no idea what the gas flow was - see measurements and results below.Weldtec- Check wire feed speed with a tape measure and stop watch.- gas flow 15-25 cfhchicksdigwagons- It sounds to me like a lack of gas flow. If I ever forget to turn on the gas I usually get weld exactly like you describe. OK, I had no idea what my wire feed speed was or what my gas flow was.Following Weldtec suggestion, I performed calibrations of my welder settings for wire feed speed. I then performed a calibration of my gas regulator for flow rates using CO2.Wire Feed Speed CalibrationThis was easy; using a stopwatch I measured how much wire came out in 6 seconds (as Weldtec suggested) at each successive setting of the wire speed adjustment knob. I rewound the wire after each run. Repeatability was good. Wire speed was unaffected by amperage settings.Wire Feed – Speed CalibrationSetting-------inches/sec-------inches/hour0----------------1.6-------------100.5----------------1.9------------1131-----------------2.4------------1451.5---------------2.8------------1702-----------------3.2------------1902.5---------------3.7------------2203-----------------3.9------------2353.5---------------4.5------------2704-----------------5.0------------3004.5---------------5.7------------3405-----------------5.9------------3555.5---------------6.4------------3856-----------------6.9------------4156.5---------------7.6------------4557-----------------8.2------------4907.5---------------8.3------------5008-----------------9.2------------5508.5---------------9.5------------5709----------------10.0------------6009.5--------------10.2------------61010---------------10.2------------610CO2 Gas Flow – Regulator CalibrationThis was a challenge. I got a 4 litre clear plastic jug that used to contain windshield washer fluid. Using a marker (waterproof), I drew a line around the midpoint of the jug – the 2-litre line. I filled the jug with water, covered the spout and upended it in a sink partially full of water – so I had an upside down jug full of water sitting in a sink containing about 4 inches of water.At first, I simply ran a plastic tube from the regulator into the spout of the upended jug. At various setting of the regulator, I turned on the gas valve and timed (stopwatch) how long it took for the gas, bubbling into the jug, to displace water – lowering the level until the 2-litre line. Thus, I had the time in seconds to flow 2 litres of gas. The flow rates looked pretty high and I was suspicious; by using a plastic tube straight from the regulator I had bypassed the welder completely and maybe the resistance to gas flow in welder was higher? After all, the welder gas tubing is smaller and longer plus there are restrictive orifice holes in the nozzle.I repeated the calibration attaching a short length of plastic tubing directly to the nozzle of the welder. Walla! The new flow rates were much lower – about 1 / 2 of the previous values! Repeatability was good – as long as I turned the screw in from the same direction. E.g. Turning in the screw from ‘0’ to ‘3’ was repeatable but did not give the same flow rate as turning the screw out from ‘4’ to ‘3’. Here are the values I measured with gas flowing though the welder; the ‘settings’ are in turns of the regulator screw from when I first felt contact resistance while turning the screw into the regulator body.CO2 Gas Flow – Regulator CalibrationSetting------litres/min------cubic feet/hour0---------------0---------------0.5--------------0---------------01---------------0---------------01.25-----------3.4--------------7.31.5------------4.5--------------9.61.75-----------5.7-------------12.12--------------7.0-------------152.5------------8.9-------------18.83--------------9.8-------------20.73.5-----------13.0-------------274-------------17.1-------------36.34.25----------17.1-------------36.3When I made the ‘no stick’ welds, I had used approximate settings as follows:- T weld on 22 gauge plates:Wire Speed = ‘1’ (2.4 inches/sec or 145 inches/minute)Regulator = ‘1.5 to 2.5’ (4.5 to 9 litres/minute or 9.6 to 18.8 cubic feet per hour)- Nut to Screw:Wire Speed = ‘0.5’ (1.9 inches/sec or 113 inches/minute)Regulator = ‘2’ (7 litres/minute or 15 cubic feet per hour)Do these wire feed and gas flow rates reveal any clues to the problem?Rick VLast edited by Rick V; 08-11-2006 at 11:28 AM.
Reply:Ok, sorry I can't add anything that hasn't already been mentioned, but I gotta make a comment. PLEASE, nobody ask him to do any "in depth" tests of this equipment!!! Wow, are you some kind of lab tech or maybe a calibration tech? That is the most elaborate testing on a mig welder I've heard...
Reply:You say you are using co2 from paint ball canisters? Is that pure?
Reply:Update observations on welding
.Ok so I tried welding a simple lap joint between two 1/16 inch thick mild-steel plates. These plates were ideal because they had been previously welded professionally; I could see a beautiful low profile weld bead about 3/32 inch wide rising just above the 1/16 inch thickness of the lap joint. So I had a perfect example of what I wanted to achieve!I learned a few things but
my welds still dont stick!Preparation: I removed the surface rust by grinding both plates bright and shiny in the areas I would be welding. I laid one plate down on a wooden table (no metal plate underneath) and I laid the second plate over the first. I camped both plates horizontally flat to the wooden table. I attached the ground clamp digging into both plates on their shiny area,CO2 Gas Flow: I welded an inch length without gas lots of sparks and metal globules flying. Hey, that weld looked like some of my previous welds = porosity (like volcanic pumice) and not much stick - particularly to the lower plate.Things improved markedly when I turned the gas on much less metal globules flying (maybe less than flux-core) and a more stable arc. The welds seemed similar at gas flows from a low of 10 to a high of 21 cubic feet per hour so at least I now have good gas coverage! (I guess that answers riley mcmillan question - the paintball CO2 is pure enough. Actually the paint ball suppliers use the same tanks most welders do.)I tried several short welds, varying the amperage from about 30 to 70 amps and wire feed speed from a low of 145 inches/minute to a high of 355 inches per minute. However, no matter what combination of amperage and wire feed, I obtained good fusion only to the 1/16 inch thick vertical edge of the upper plate and almost no fusion to the lower plate. I tried angling the gun to put more heat into the lower plate but that achieved little.I checked contact tip polarity with a voltmeter. The electrode was positive and ground was negative. By this time I was pretty frustrated, so I reversed polarity and tried again with electrode negative and ground positive. That was definitely worse snarling popping arc rather unstable and uneven weld bead (yes, the gas was on.) So, I put things back the way they were supposed to be: electrode positive and ground negative.I then tried once more with a wire speed of 170 inches/minute and 70 amps. This time I moved very slowly along the lap joint for about 1 inch. Finished, I lifted my helmet I could see a red after glow and smell hot metal for the first time. I did obtain some fusion (say 3/8 inch long) into the lower plate not a lot but something!So, where does this leave me? I am definitely not getting enough heat into the weld area.Compared to the professional weld that has a slightly concave ( profile, my welds have a much higher convex ) profile. The professional weld looks like the weld metal almost flowed into the joint the weld profile is even with the top plate and spreads out about 3/32 inch onto the bottom plate. In comparison, my welds look fast freeze looping 3/32 to 1/8 inch above the edge of the top plate, then rolling over spherically and plunging to meet the bottom plate at an angle near 90 degrees and 1/8 inch out from the edge of the top plate.I can only think of two other things that may be limiting my ability to melt into the base plate:1 Contact tip: I have yet to replace my 0.030 inch contact tip with the proper 0.023 inch tip to match the 0.023 wire I am using. Any idea if this is likely to have a big effect?2 Weld wire: I am using a wire made by ENI (Italy) sold by Princess Auto. It is designated as ER49 S-6 certified by the Canadian Welding Bureau to CSA Standard W48.01. The wire also bears the AWS certification as E70 S-6. Any idea if a wire change is likely to give an improvement?By the way, I dont lack for AC input power. The welder is plugged into a separate 117-volt circuit that runs 10-gauge wire with 40 amp breaker.Any possibilities?Rick V
Reply:Rick,Here's something to try... to develop more heat at the weld area try moving the wire from side to side over the joint at the slowest wire feed rate. Don't worry about getting a wider bead than what you want to end up with. This is just a test to see if you are developing enough heat for adequate penetration. Once you have developed enough heat by slowing down your advance speed, then you can play with bead size and welding speed. Good luck. Let us know.
Reply:You are going to get a lot of problems running an oversize contact tube. Purchase the proper sized tip. Also flux core traditionally is to be run back hand and hard wire is run forehand. You should be pointing the gun slightly in the direction you are travelling. When just feeding into the parent metal look at the wire and the puddle. If the wire is trying to dip into the puddle you need more voltage or less wire feed speed. To clarify: When you increase wire speed you are increasing the heat or amperage. When you adjust the "range" of "heat" on these small machines you are really increasing or decreasing the voltage. Try the maximum range then turn your wire speed up too high. The wire should stub out on your metal when you pull the trigger. Keep the wire running as you turn your speed down until you have a stable arc.
Reply:1 Contact tip: I have yet to replace my 0.030 inch contact tip with the proper 0.023 inch tip to match the 0.023 wire I am using. Any idea if this is likely to have a big effect?
Reply:Oops ! One more thing. What kind of drive rolls have you got on there. If you are trying to drive .023 with rolls designed for .030 or larger? You might have a problem with irregular feeding. This would only show up when welding with an arc and there is sticking/drag at the contact tip.
Reply:Many years ago I bought an 80 amp flux core machine from sam's club. When everything was set right it would weld up to about 1/8 thick. If anything is off just a little bit, look out. What I am saying is that I would not consider any wire feed or mig with less than 100 amp capacity. I gave the thing away.
Reply:I've never used straight CO2, I have used pure Argon on a mig in a pinch and it welds like crap. Can anyone else elaborate on the use of CO2.DewayneDixieland WeldingMM350PLincoln 100Some torchesOther misc. tools
Reply:Yeh, you should get that tip changed soon because if it was reamed out from a lot of wire run through it it could be completely sloppy. But that should cause some erratic problems not one long standing issue. Heck some guys run a .035 tip with .030 wire so do the math. A just right tip is nice. A tip too tight is bad. A tip too loose is bad. Gas is about the same. There's some room to roam in between too little and too much. If the all settings are correct except the gas, with too little you'll get some porosity and small volcanos coming out of the solidifying metal. Too much and you may get similar due to turbulance or possibly a quick chilling effect on the bead. Keep in mind there is a different between post flow for cooling and high flows that chill. I'll bet that's not an issue here. Here's my guess, do like lotech says and crank that puppy up. Get right to the upper limits and work your way back down. Without some manufacuteres charts per wire size and type you are kind of on your own. Don't hold back. I can't imagine a 70 amp wire feed being too devastating to experiment with. Oh, and as mentioned, do a side to side weave. With a small machine you're not going to get any heat into the other half unless you put the arc right into it. You've done some wire speed testing and there are some generic numbers out there stating some crude amps per inch that can be squeezed out of any particular size of wire. Gets you in the ball park of amps, close anyway. BTW, I'm sure you meant to list the wire speed in inches per minute not inches per hour. 610 inches per hour won't get you much
Reply:Here some generic hints out of a Millers manual. Each .001 inch of material thickness requires 1 (one) amp. So 16 gauge is going to need about 60 amps. Upper limits of your machine. At mid range on voltage .023 wire will need about 3.5 inches to provide 1 amp. So for 60 amps you should be around 210 ipm, high end on the voltage depending on how settings you have and how it acts. That .023 wire should run pretty sweet on a small machine.
Reply:Originally Posted by littlefuzzI've never used straight CO2, I have used pure Argon on a mig in a pinch and it welds like crap. Can anyone else elaborate on the use of CO2.
Reply:MIG Update 2Hey all thanks for the many great responses and good suggestions.Drive RollsLotechman: I am using the correct size drive rollers for 0.023 wire serrated ones that really grip the wire."Inches Per Hour"Sandy: Good point, as you stated, I'm sure you meant to list the wire speed in inches per minute not inches per hour. So true I am SLOW but not quite crawling.Contact TipLast night, I changed the contact tip from 0.030 to 0.023 to match my 0.023 wire. There was no change in performance welds still didnt stick. (Now I am stuck with 10 rather useless tips!)Contact Tip-to-Work Distance (Wire Extension/Stick Out)According to ESABs Fables, the heat input into the weld is affected by wire stick out. (The more stick out, the less heat input the weld.) I tried varying the wire extension from hardly being able to see the wire for the nozzle to about 1/2 inch sticking out past the nozzle end (almost 3/4 inch from the contact tip). The longer the stick out the narrower the weld width became but none of the variations resulted in improved fusion to the lower plate.Wire Feed SpeedAccording to ESABs Fables, the heat input into the weld is proportional to the product of amperage times wire feed speed. (The higher the wire speed, the higher the heat into the weld.)At maximum amperage setting (70A), I laid down 5 welds with wire speed ranging from 100 inches/minute to 355 inches/minute (bumping my hand up & down) something around 180 seemed best. However, none of the variations in wire speed resulted in the desired fusion to the lower plate.ButteringI thought, what if I butter the lower plate first, then a light grind and try my lap weld? At this point, I wondered if I could even weld to a flat plate! OK, this butter weld went well good fusion. [See Sandy, the Miller manual is just about right on.] I then ground down the butter weld, overlaid the plates and welded the lap joint. Nothing Doing - the weld stuck only to the edge of the upper plate with no fusion to the lower base plate. (Same as before.)Return to Flux Core!By now I was wondering if something was wrong with my welder. Could I weld these plates with flux core wire? So I changed the polarity back to electrode negative and went back to 0.030 flux core. First weld at max amp setting (70A) and wire speed of about 190 inches/minute looked too hot! some burn through on the edge of the upper plate. I turned down to the minimum amperage (setting 1 of 4) and 150 inches/minute and welded again. These were all successful welds! Full fusion on all counts!Wow there sure is a massive difference in heat input between 0.023 solid steel wire/CO2 and 0.030 flux core wire. On my machine at maximum amp setting (70A) MIG (CO2) cannot generate enough heat to lap weld two 1/16 inch thick plates while flux-core wire handles the same job easily at minimum amperage setting.The only question left is would I have more MIG success if I changed to larger solid wire diameter such as 0.030 or 0.035? Would I obtain enough heat input into the weld to obtain fusion to the lower base plate? Probably marginal eh? - still for $8 worth of wire, I want to know the answer!On the other hand, maybe the problem is just fundamental - as Riley Mcmillan said, What I am saying is that I would not consider any wire feed or mig with less than 100 amp capacity.Rick VMIG Welds dont stick I am making a transition from flux-core wire feed to gas (CO2) wire feed and am having problems getting my welds to stick. Any advice or suggestions would be appreciated.My welder is a Canadian Tire MasterCraft (Campbell Hausfeld) 115 volt input with 4 output settings: two for 15A input and two higher ones for 20A input. Maximum output is 70 Amps DC.I was previously using ENI flux-core wire of 0.030 inch diameter. This worked well for steel of thickness of 18 gauge or greater nice on 1/8 inch stock. However, even at the lowest amperage setting I had to be very careful not to burn through on 20 to 22 gauge sheet usually I had to make a series of brief spot welds (stitching) then return to fill in the gaps.I am making the transition to gas. Because I dont weld a great deal, I want super portability, no rental fees and the fact that my son works in a paint-ball store, I opted to use carbon dioxide gas. I bought two 20 ounce CO2 capacity aluminum paint-ball tanks (10 cubic feet of CO2 in each) for ~$40. So, I am restricted to using CO2.As per the welder instructions, I reversed the DC polarity of the output (flux-core to MIG). I also changed to ENI 0.023 diameter inch solid MIG wire. Now my problem is the opposite of that I had with flux-core wire I seem to have difficulty getting fusion (burn-through is no longer the problem.).Clues?1 - I tried a Tee weld between two small plates of 22 gauge steel. I used my angle grinder to clean up all the pieces before hand. The horizontal plate was clamped to a metal table, the vertical plate was held in place by a magnet. During welding, I noticed a great deal more flying metal gobuls, sparks and splatter than I was used to with flux-core wire. Looking at the result, the weld appeared to stick on the vertical plate but not on the horizontal plate (maybe the heat was being sucked away by contact with the metal table?) No matter what the amperage setting I tried, the weld profile looked high and lumpy (round spheres or beads) and the weld was easily knocked apart with a chipping hammer. There were only a few spot of decent fusion along the length of the weld.2 I tried welding a mild-steel nut to the head of an 8-32 mild steel screw. No matter what output settings I used, the weld bead tended to be high in profile. It was easy to twist or chip the weld apart. Again, it looked like I had insuffient heat input and was only getting marginal fusion in a few spots. I appeared to be welding fine to the previous weld metal - making nice spherical lumps but the weld-metal lumps were not well fused to the base metal of either the nut or the screw.3 - I am keeping the welder nozzle close in to the weld so as not to lose my gas shield. However, I am feeling my way as to the amount of gas flow to use and the speed of wire-feed so those may be contributing factors. Perhaps someone can read these clues and say Ah ha, your problem is
.Any suggestions?Rick V
Reply:When you switched from flux to gas, did you switch the nozzle on the end of the gun to allow the gas to flow?What about the contact tip. Did you switch it from .030" to an .023"?If all of that is good, it sounds as if your wire speed is a bit fast. Does it pop and sputter while you're trying to weld? If it does, try turning the wire speed down. You also may have to adjust your "hand speed". Since the flux-core burns hotter, you can move your hand a lot faster...try slowing down and see if it helps.BTW, your gas flow should be around 12-15cfh.http://all-a-cart.comWelding Cart Kits and accessories
Reply:If your machine has voltage settings like hi med lo set to hi.Check wire feed speed with a tape measure and stop watch.Feed wire for 6 seconds and measure. Example 15 inches long = 150 ipm.or 3810 mm/minPolarity DC electrode positive DCEP or reverse Stick out should be 1/4 to 3/8 " or 6.4 to 8.6 mmgas flow 15-25 cfhIf the wire hits the plate w/o melting decrease wfs until the wire is melting off and you can't feel it touch the plate. Try supprting the project on something thinner to avoid the heat sink.Weldtek
Reply:It sounds to me like a lack of gas flow. If I ever forget to turn on the gas I usually get weld exactly like you describe.
Reply:are you getting any porosity in your welds when you grind them. What is your weld settings at including your gas flow?
Reply:the machine is "running in reverse"there was another thread about this awhile ago..seems when you switch from flux to gas the machine has to go "backwards" of what its set up for now..flux is neg..gas is pos. ground..or vice-versawichever whatever thats the problem......zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:On my MillerMatic 175 you have to change the polarity of the welder when you change between flux and solid wire. Basically swap the hot and neutral around.
Reply:Originally Posted by Rick VAs per the welder instructions, I reversed the DC polarity of the output (flux-core to MIG).
Reply:Unless he had it wrong to begin with... I seem to recall testing something and Flux Cored seemed to work okay both ways but Gas Sheilded was very picky...Its been a while since I played with that however.
Reply:Originally Posted by chicksdigwagonsUnless he had it wrong to begin with... I seem to recall testing something and Flux Cored seemed to work okay both ways but Gas Sheilded was very picky...Its been a while since I played with that however.
Reply:I've recently completed making a large metal security door, and had a couple of really bad days when attempting to weld with my 110v mig. Results were much like yours, even though I have previously been very satisfied with my welds. Now, the welder is again producing excellent beads and penetration. Wasn't using an extension cord in either case, which can result in situations like yours. The only thing that comes to mind, now that the machine is working again, is that, during the days that the weather was around 100 degrees, we had several fans running in the house that might have caused a voltage drop, which affected my mig. Or, people were running lots of air conditioners, which had the same effect. Sure glad my mig has got its buzz back.Have you pros ever heard of high electricity usage causing welding machines to lose their zip (or zap)?
Reply:Hi fellows - thanks for all the suggestions.Let me answer some of your questions:In respect to polarity, I followed the instructions in the manual to change the polarity. It is not really possible to make an error because one removes a cover plate with pointer that fits only one way over a small bus-bar assembly. To change polarity, one rotates the bus-bar assembly 90 degrees and replaces the cover plate - that now points 90 degrees to previously. The cover plate comes from the factory pointing to the upper right - "ELECTRODE NEGATIVE FLUX-CORE WIRE". After I rotated the bus-bar assembly through 90 degrees, the installed cover plate pointed to the upper left - "ELECTRODE POSITIVE MIG WIRE".ZTFab- When you switched from flux to gas, did you switch the nozzle on the end of the gun to allow the gas to flow?The nozzle is the same for both.On/off gas flow is controlled right at the gun trigger (O-ring gas valve); there is no electrical gas solenoid located inside the welder. (This might be useful if you wanted to use a foot switch to turn off AC input into the welder while you kept the gun trigger on to provide run-on gas flow.)- What about the contact tip. Did you switch it from .030" to an .023"?No, I didn't do that yet... I may have a little gas passing between the wire and the hole. However, the gas does not feed down the same tube as the wire and exits through about 8 holes located back of the contact tip.- Wire SpeedI didn't know - see measurements and results below.- BTW, your gas flow should be around 12-15cfh. I had no idea what the gas flow was - see measurements and results below.Weldtec- Check wire feed speed with a tape measure and stop watch.- gas flow 15-25 cfhchicksdigwagons- It sounds to me like a lack of gas flow. If I ever forget to turn on the gas I usually get weld exactly like you describe. OK, I had no idea what my wire feed speed was or what my gas flow was.Following Weldtec suggestion, I performed calibrations of my welder settings for wire feed speed. I then performed a calibration of my gas regulator for flow rates using CO2.Wire Feed Speed CalibrationThis was easy; using a stopwatch I measured how much wire came out in 6 seconds (as Weldtec suggested) at each successive setting of the wire speed adjustment knob. I rewound the wire after each run. Repeatability was good. Wire speed was unaffected by amperage settings.Wire Feed – Speed CalibrationSetting-------inches/sec-------inches/hour0----------------1.6-------------100.5----------------1.9------------1131-----------------2.4------------1451.5---------------2.8------------1702-----------------3.2------------1902.5---------------3.7------------2203-----------------3.9------------2353.5---------------4.5------------2704-----------------5.0------------3004.5---------------5.7------------3405-----------------5.9------------3555.5---------------6.4------------3856-----------------6.9------------4156.5---------------7.6------------4557-----------------8.2------------4907.5---------------8.3------------5008-----------------9.2------------5508.5---------------9.5------------5709----------------10.0------------6009.5--------------10.2------------61010---------------10.2------------610CO2 Gas Flow – Regulator CalibrationThis was a challenge. I got a 4 litre clear plastic jug that used to contain windshield washer fluid. Using a marker (waterproof), I drew a line around the midpoint of the jug – the 2-litre line. I filled the jug with water, covered the spout and upended it in a sink partially full of water – so I had an upside down jug full of water sitting in a sink containing about 4 inches of water.At first, I simply ran a plastic tube from the regulator into the spout of the upended jug. At various setting of the regulator, I turned on the gas valve and timed (stopwatch) how long it took for the gas, bubbling into the jug, to displace water – lowering the level until the 2-litre line. Thus, I had the time in seconds to flow 2 litres of gas. The flow rates looked pretty high and I was suspicious; by using a plastic tube straight from the regulator I had bypassed the welder completely and maybe the resistance to gas flow in welder was higher? After all, the welder gas tubing is smaller and longer plus there are restrictive orifice holes in the nozzle.I repeated the calibration attaching a short length of plastic tubing directly to the nozzle of the welder. Walla! The new flow rates were much lower – about 1 / 2 of the previous values! Repeatability was good – as long as I turned the screw in from the same direction. E.g. Turning in the screw from ‘0’ to ‘3’ was repeatable but did not give the same flow rate as turning the screw out from ‘4’ to ‘3’. Here are the values I measured with gas flowing though the welder; the ‘settings’ are in turns of the regulator screw from when I first felt contact resistance while turning the screw into the regulator body.CO2 Gas Flow – Regulator CalibrationSetting------litres/min------cubic feet/hour0---------------0---------------0.5--------------0---------------01---------------0---------------01.25-----------3.4--------------7.31.5------------4.5--------------9.61.75-----------5.7-------------12.12--------------7.0-------------152.5------------8.9-------------18.83--------------9.8-------------20.73.5-----------13.0-------------274-------------17.1-------------36.34.25----------17.1-------------36.3When I made the ‘no stick’ welds, I had used approximate settings as follows:- T weld on 22 gauge plates:Wire Speed = ‘1’ (2.4 inches/sec or 145 inches/minute)Regulator = ‘1.5 to 2.5’ (4.5 to 9 litres/minute or 9.6 to 18.8 cubic feet per hour)- Nut to Screw:Wire Speed = ‘0.5’ (1.9 inches/sec or 113 inches/minute)Regulator = ‘2’ (7 litres/minute or 15 cubic feet per hour)Do these wire feed and gas flow rates reveal any clues to the problem?Rick VLast edited by Rick V; 08-11-2006 at 11:28 AM.
Reply:Ok, sorry I can't add anything that hasn't already been mentioned, but I gotta make a comment. PLEASE, nobody ask him to do any "in depth" tests of this equipment!!! Wow, are you some kind of lab tech or maybe a calibration tech? That is the most elaborate testing on a mig welder I've heard...
Reply:You say you are using co2 from paint ball canisters? Is that pure?
Reply:Update observations on welding
.Ok so I tried welding a simple lap joint between two 1/16 inch thick mild-steel plates. These plates were ideal because they had been previously welded professionally; I could see a beautiful low profile weld bead about 3/32 inch wide rising just above the 1/16 inch thickness of the lap joint. So I had a perfect example of what I wanted to achieve!I learned a few things but
my welds still dont stick!Preparation: I removed the surface rust by grinding both plates bright and shiny in the areas I would be welding. I laid one plate down on a wooden table (no metal plate underneath) and I laid the second plate over the first. I camped both plates horizontally flat to the wooden table. I attached the ground clamp digging into both plates on their shiny area,CO2 Gas Flow: I welded an inch length without gas lots of sparks and metal globules flying. Hey, that weld looked like some of my previous welds = porosity (like volcanic pumice) and not much stick - particularly to the lower plate.Things improved markedly when I turned the gas on much less metal globules flying (maybe less than flux-core) and a more stable arc. The welds seemed similar at gas flows from a low of 10 to a high of 21 cubic feet per hour so at least I now have good gas coverage! (I guess that answers riley mcmillan question - the paintball CO2 is pure enough. Actually the paint ball suppliers use the same tanks most welders do.)I tried several short welds, varying the amperage from about 30 to 70 amps and wire feed speed from a low of 145 inches/minute to a high of 355 inches per minute. However, no matter what combination of amperage and wire feed, I obtained good fusion only to the 1/16 inch thick vertical edge of the upper plate and almost no fusion to the lower plate. I tried angling the gun to put more heat into the lower plate but that achieved little.I checked contact tip polarity with a voltmeter. The electrode was positive and ground was negative. By this time I was pretty frustrated, so I reversed polarity and tried again with electrode negative and ground positive. That was definitely worse snarling popping arc rather unstable and uneven weld bead (yes, the gas was on.) So, I put things back the way they were supposed to be: electrode positive and ground negative.I then tried once more with a wire speed of 170 inches/minute and 70 amps. This time I moved very slowly along the lap joint for about 1 inch. Finished, I lifted my helmet I could see a red after glow and smell hot metal for the first time. I did obtain some fusion (say 3/8 inch long) into the lower plate not a lot but something!So, where does this leave me? I am definitely not getting enough heat into the weld area.Compared to the professional weld that has a slightly concave ( profile, my welds have a much higher convex ) profile. The professional weld looks like the weld metal almost flowed into the joint the weld profile is even with the top plate and spreads out about 3/32 inch onto the bottom plate. In comparison, my welds look fast freeze looping 3/32 to 1/8 inch above the edge of the top plate, then rolling over spherically and plunging to meet the bottom plate at an angle near 90 degrees and 1/8 inch out from the edge of the top plate.I can only think of two other things that may be limiting my ability to melt into the base plate:1 Contact tip: I have yet to replace my 0.030 inch contact tip with the proper 0.023 inch tip to match the 0.023 wire I am using. Any idea if this is likely to have a big effect?2 Weld wire: I am using a wire made by ENI (Italy) sold by Princess Auto. It is designated as ER49 S-6 certified by the Canadian Welding Bureau to CSA Standard W48.01. The wire also bears the AWS certification as E70 S-6. Any idea if a wire change is likely to give an improvement?By the way, I dont lack for AC input power. The welder is plugged into a separate 117-volt circuit that runs 10-gauge wire with 40 amp breaker.Any possibilities?Rick V
Reply:Rick,Here's something to try... to develop more heat at the weld area try moving the wire from side to side over the joint at the slowest wire feed rate. Don't worry about getting a wider bead than what you want to end up with. This is just a test to see if you are developing enough heat for adequate penetration. Once you have developed enough heat by slowing down your advance speed, then you can play with bead size and welding speed. Good luck. Let us know.
Reply:You are going to get a lot of problems running an oversize contact tube. Purchase the proper sized tip. Also flux core traditionally is to be run back hand and hard wire is run forehand. You should be pointing the gun slightly in the direction you are travelling. When just feeding into the parent metal look at the wire and the puddle. If the wire is trying to dip into the puddle you need more voltage or less wire feed speed. To clarify: When you increase wire speed you are increasing the heat or amperage. When you adjust the "range" of "heat" on these small machines you are really increasing or decreasing the voltage. Try the maximum range then turn your wire speed up too high. The wire should stub out on your metal when you pull the trigger. Keep the wire running as you turn your speed down until you have a stable arc.
Reply:1 Contact tip: I have yet to replace my 0.030 inch contact tip with the proper 0.023 inch tip to match the 0.023 wire I am using. Any idea if this is likely to have a big effect?
Reply:Oops ! One more thing. What kind of drive rolls have you got on there. If you are trying to drive .023 with rolls designed for .030 or larger? You might have a problem with irregular feeding. This would only show up when welding with an arc and there is sticking/drag at the contact tip.
Reply:Many years ago I bought an 80 amp flux core machine from sam's club. When everything was set right it would weld up to about 1/8 thick. If anything is off just a little bit, look out. What I am saying is that I would not consider any wire feed or mig with less than 100 amp capacity. I gave the thing away.
Reply:I've never used straight CO2, I have used pure Argon on a mig in a pinch and it welds like crap. Can anyone else elaborate on the use of CO2.DewayneDixieland WeldingMM350PLincoln 100Some torchesOther misc. tools
Reply:Yeh, you should get that tip changed soon because if it was reamed out from a lot of wire run through it it could be completely sloppy. But that should cause some erratic problems not one long standing issue. Heck some guys run a .035 tip with .030 wire so do the math. A just right tip is nice. A tip too tight is bad. A tip too loose is bad. Gas is about the same. There's some room to roam in between too little and too much. If the all settings are correct except the gas, with too little you'll get some porosity and small volcanos coming out of the solidifying metal. Too much and you may get similar due to turbulance or possibly a quick chilling effect on the bead. Keep in mind there is a different between post flow for cooling and high flows that chill. I'll bet that's not an issue here. Here's my guess, do like lotech says and crank that puppy up. Get right to the upper limits and work your way back down. Without some manufacuteres charts per wire size and type you are kind of on your own. Don't hold back. I can't imagine a 70 amp wire feed being too devastating to experiment with. Oh, and as mentioned, do a side to side weave. With a small machine you're not going to get any heat into the other half unless you put the arc right into it. You've done some wire speed testing and there are some generic numbers out there stating some crude amps per inch that can be squeezed out of any particular size of wire. Gets you in the ball park of amps, close anyway. BTW, I'm sure you meant to list the wire speed in inches per minute not inches per hour. 610 inches per hour won't get you much
Reply:Here some generic hints out of a Millers manual. Each .001 inch of material thickness requires 1 (one) amp. So 16 gauge is going to need about 60 amps. Upper limits of your machine. At mid range on voltage .023 wire will need about 3.5 inches to provide 1 amp. So for 60 amps you should be around 210 ipm, high end on the voltage depending on how settings you have and how it acts. That .023 wire should run pretty sweet on a small machine.
Reply:Originally Posted by littlefuzzI've never used straight CO2, I have used pure Argon on a mig in a pinch and it welds like crap. Can anyone else elaborate on the use of CO2.
Reply:MIG Update 2Hey all thanks for the many great responses and good suggestions.Drive RollsLotechman: I am using the correct size drive rollers for 0.023 wire serrated ones that really grip the wire."Inches Per Hour"Sandy: Good point, as you stated, I'm sure you meant to list the wire speed in inches per minute not inches per hour. So true I am SLOW but not quite crawling.Contact TipLast night, I changed the contact tip from 0.030 to 0.023 to match my 0.023 wire. There was no change in performance welds still didnt stick. (Now I am stuck with 10 rather useless tips!)Contact Tip-to-Work Distance (Wire Extension/Stick Out)According to ESABs Fables, the heat input into the weld is affected by wire stick out. (The more stick out, the less heat input the weld.) I tried varying the wire extension from hardly being able to see the wire for the nozzle to about 1/2 inch sticking out past the nozzle end (almost 3/4 inch from the contact tip). The longer the stick out the narrower the weld width became but none of the variations resulted in improved fusion to the lower plate.Wire Feed SpeedAccording to ESABs Fables, the heat input into the weld is proportional to the product of amperage times wire feed speed. (The higher the wire speed, the higher the heat into the weld.)At maximum amperage setting (70A), I laid down 5 welds with wire speed ranging from 100 inches/minute to 355 inches/minute (bumping my hand up & down) something around 180 seemed best. However, none of the variations in wire speed resulted in the desired fusion to the lower plate.ButteringI thought, what if I butter the lower plate first, then a light grind and try my lap weld? At this point, I wondered if I could even weld to a flat plate! OK, this butter weld went well good fusion. [See Sandy, the Miller manual is just about right on.] I then ground down the butter weld, overlaid the plates and welded the lap joint. Nothing Doing - the weld stuck only to the edge of the upper plate with no fusion to the lower base plate. (Same as before.)Return to Flux Core!By now I was wondering if something was wrong with my welder. Could I weld these plates with flux core wire? So I changed the polarity back to electrode negative and went back to 0.030 flux core. First weld at max amp setting (70A) and wire speed of about 190 inches/minute looked too hot! some burn through on the edge of the upper plate. I turned down to the minimum amperage (setting 1 of 4) and 150 inches/minute and welded again. These were all successful welds! Full fusion on all counts!Wow there sure is a massive difference in heat input between 0.023 solid steel wire/CO2 and 0.030 flux core wire. On my machine at maximum amp setting (70A) MIG (CO2) cannot generate enough heat to lap weld two 1/16 inch thick plates while flux-core wire handles the same job easily at minimum amperage setting.The only question left is would I have more MIG success if I changed to larger solid wire diameter such as 0.030 or 0.035? Would I obtain enough heat input into the weld to obtain fusion to the lower base plate? Probably marginal eh? - still for $8 worth of wire, I want to know the answer!On the other hand, maybe the problem is just fundamental - as Riley Mcmillan said, What I am saying is that I would not consider any wire feed or mig with less than 100 amp capacity.Rick V |
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发表于 2021-9-1 00:59:31