Hacked Off

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So here's a question. I was getting tired today of not being able to get the tip close enough for the weld to sound right (or look right) and couldn't see the puddle past the nozzle. So I hacked the end of the copper nozzle off flush with the tip, about 3/8", and it fixed the weld. I cold get the tip the right distance from the workpiece for the power and the wire speed and it came out pretty good... for me. Is there something wrong with that? Will I adversely affect my gas coverage? It doesn't seem to have had a negative impact. Quite the opposite but I have no idea if my "fix-it" will hurt the welder.
Reply:You may be alright if it has not affected gas coverage. If you lose that, porosity is sure to follow.City of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:Hello jlames, the distance that the tip is set-back/flush/or extended past the nozzle is sometimes determined by the selection of a specific nozzle type and associated purpose. Think in these simple terms: with the tip recessed deeply into the nozzle and needing to have a fairly long "stick-out" distance for a particular welding challenge there is a chance for the wire to whip or come out with a circular motion(cast) making it hard to direct the weld bead, this condition can also adversely effect the arc performance in some instances or enhance it in others. A lot of variables are associated with visible stick-out, electrical stick-out, and stick-out in general as it relates to wire type, diameter, process, and other variables. Bottom line in this instance is exactly as others have said, if you lose gas coverage then you you will either need to consider adjustments to flow, distance from the nozzle outer lip to work, or possibly the distance of extension, flushness, or recession of the contact tip in relation to the outer lip of the nozzle. Personally, I would say that if your welds are coming out satisfactorily visually and mechanically that you are a OK. You will not do any harm to the welding machine or it's associated peripheral pieces. Good luck and best regards, Allanaevald
Reply:Thanks gents. I didn't know if my "If it doesn't work, get a bigger hammer" attitude would work or not. The problem was I was welding an inside joint where the two, 2-inch legs were less than 90-degrees preventing the nozzle from getting to the joint. The stock set-up works fine on flat and outside welds but I just couldn't get the tip close enough to the work with the restrictive angle. So, it had no porosity and I just walked out to the shop and beat the tar out of it and the pieces folded but the weld didn't break so if it won't hurt the machine, I guess I have a "special-circumstance" tip now!!! Thanks. Necessity will always be the mother of invention.
Reply:I am not sure what type of gun you have but Tweco makes different length contact tips for their guns.  At least the 400 amp gun any way.  Maybe you can mix and match different nozzles and contact tips to get the result you want.Dan D.
Reply:You fixed it Jonathan. That nozzle concentrates the gas to the puddle. That's it. Although if there is an earthquake or fire near you I will tell everyone it's your fault due to the nozzle episode.......Just trying to helpArcon Workhorse 300MSPowcon 400SMTPowcon SM400 x 2Powcon SM3001968 SA200 Redface1978 SA250 DieselMiller Super 32P FeederPre 1927 American 14" High Duty LatheK&T Milwaukee 2H Horizontal MillBryan
Reply:Thank alot Bryan!!! I was countin' on sayin' "I was no where NEAR the ignition point, Ossifer. I was up in Whitewater with Bryan!".As for the Tweko, that's an idea. Thanks!
Reply:I've run them flush forever.Keep a little longer(1/4" inset) one laying around for doing flat welds on thin crap like quarter panels or those evul mower decks everyone keeps talking about.You can keep the nozzle in contact with the sheet and pull a straight fast line leaving a weld bead about 3/16-1/4  wide(.025 wire).Bubble gumTooth pixDuct tapeBlack glueGBMF hammerScrew gun --bad battery (see above)
Reply:This is out of some PDF I downloaded at some point. Can't say from where or I'd give ya a link. I've seen others stating the same things in different ways. Note that this doc calls it a contact "tube" instead of "tip" Same thing tho. "CONTACT TUBE-GAS NOZZLE RELATIONSHIPOn a standard type-welding gun, it is important how far the contact tube sticks out of the gas nozzle.This contact tube-gas nozzle relationship is important for proper electrode extension (stickout), gas shielding,and heat buildup in the contact tube and gun.For short circuit transfer, electrode extensions (stickouts) are shorter than for spray transfer. Therefore, it helpsto have the contact tube nearly flush with the end of the gas nozzle for short-circuiting transfer. In some cases,the contact tube may even extend slightly beyond the end of the gas nozzle. This can be accomplished byusing either a shorter gas nozzle or a longer contact tube. Gun manufacturers will vary on the method used.The contact tube should not be recessed up inside the nozzle for short circuit transfer. This can cause a longelectrode extension (stickout), causing a high, ropey, spattery weld.For spray or globular transfer, more heat and longer electrode extensions are used. This can provide higherdeposition because of higher parameters and the wire having a longer "preheat" time before it enters the arc.Thus it takes less amperage from the welding machine to melt to wire. This allows faster wire feed speed at agiven amperage. The higher wire feed speed deposits more metal in a given amount of time.A contact tube too close to the weld puddle could easily overheat, expand and seize the wire. Overheating,expanding, and seizing the electrode wire can cause burnback or poor wire feeding characteristics. To helpeliminate this it helps to have the contact tube recessed about an 1/8". This is to allow for more electrodeextension, and the contact tube is further from the weld puddle. It also allows the gas nozzle to be closer to thework, thus providing better shielding. This is done with either a longer gas nozzle or a shorter contact tube."My PM215 with the 250 amp gun came with the tip out past the nozzle about 1/16 or so. My MM175 came with the tip flush with the nozzle. I ground that nozzle off so the tip sticks out about 1/8th for the smaller wires, low amps. Keep an un-altered nozzle for the times when gas coverage is a problem.Last edited by Sandy; 02-21-2014 at 01:28 AM."The things that will destroy America are prosperity at any price, peace at any price, safety first instead of duty first, the love of soft living and the get rich quick theory of life." -Theodore Roosevelt
Reply:The 1/8" inset I can understand but mine was about 3/8 inside the nozzle. I bought this machine used a week or so ago to replace the one that was stolen in December so the previous owner may have put an aftermarket nozzle on and that was the problem. I'm not exactly flush with the tip after I cut it off; it's still a bit back which may be why I'm still getting gas coverage.
Reply:if you have doubts as to the quality of your welds after shortening the nozzle (not the tip) make a short weld sample and break/hacksaw and see for yourself what's inside?i.u.o.e. # 15queens, ny and sunny fla
Reply:Jonathan:Ive actually belt sanded the nozzle so far back the contact tip was sticking out.Granted it was for a special hard to reach area but it worked just fine.Quite a few miller migs are sent from the factory with way too much nozzle length and no shorter nozzle available.Miller Dynasty 200DXMiller Spectrum 250DMiller Millermatic 200Bunch of old blue dinosaurs....