Lincoln SP250. Must turn voltage up too high to weld

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Hello everyone,About a year or so ago I bought a Lincoln SP250 at an estate auction.  I've been learning to weld with it, so sometimes I'm not sure if it is my lack of knowledge or equipment that causes problems.  Lately I feel as though I have to turn the welder up far too high to weld certain things.Just today I was tack welding 22 gauge steel and I had to set the welder for 12 gauge steel just to keep it from popping and throwing slag (The SP250 has a digital readout with digital presets)  I don't recall this being an issue in the past.  Is this a known problem or has anyone heard of this before?In this picture you can see that the tip is recessed very far.  I'm going to ask a question about this in a separate thread, but I believe this can't be the entire problem because it has been recessed this way the entire time I have owned the machine.Thanks,Brandon
Reply:By far not an expert.But with the contact recessed so far, you already too far a stickout. Everything I have read suggests it should be near dead even.
Reply:I think that you are going to have a lot of problems with that much recess on the tip. I like mine about flush or maybe just slightly recessed.
Reply:Looks like someone has the gun consumables all jacked up.It should have a 52FN diffuser,32 insulator,22-62-SS nozzle and 14 series contact tip.I set my nozzle flush with the tip.
Reply:Holy crap. My mig gun looks like that. I didn't even think of the stickout being measured from the tip, Duh, I just thought of stickout as how far out from the nozzle. Thanks for this post and the answers.I'm gonna get me some new contact tipsMy given welding web rank "Solderer" Couldn't be more trueClarke Hotshot-Spoolgun flux/mig 135SG1986 Miller Dialarc 250 AC/DC
Reply:Originally Posted by WhoUtinkHoly crap. My mig gun looks like that. I didn't even think of the stickout being measured from the tip, Duh, I just thought of stickout as how far out from the nozzle. Thanks for this post and the answers.I'm gonna get me some new contact tips
Reply:Or both. lol tips are cheaper though.I think there are some extra tips on the cart that my welder came with, so I might not need to buy anything. But I am still excited this mistake was pointed out.Last edited by WhoUtink; 04-10-2013 at 12:49 AM.My given welding web rank "Solderer" Couldn't be more trueClarke Hotshot-Spoolgun flux/mig 135SG1986 Miller Dialarc 250 AC/DC
Reply:Well this is somewhat good news to me.  I was afraid that the likely answer was something to do with a failure in the circuitry of the welder.  I posted a separate thread dealing with just the question about the tip but since it seems my voltage is likely to be related to the tip I'll post my question here as well.Would the specific tip and nozzle be listed in the manual for this machine (I can find it online in a PDF)?  As of now I don't know if they are recommended to have just one type or if, because they are pieces that change depending on usage, if no specific one would be listed.Thanks,Brandon
Reply:Originally Posted by Vetteman61Well this is somewhat good news to me.  I was afraid that the likely answer was something to do with a failure in the circuitry of the welder.  I posted a separate thread dealing with just the question about the tip but since it seems my voltage is likely to be related to the tip I'll post my question here as well.Would the specific tip and nozzle be listed in the manual for this machine (I can find it online in a PDF)?  As of now I don't know if they are recommended to have just one type or if, because they are pieces that change depending on usage, if no specific one would be listed.Thanks,Brandon
Reply:Here is the manual:http://www.lincolnelectric.com/asset...oln3/im397.pdf
Reply:If the manual shows parts it will show Lincoln part numbers.The gun uses Tweco consumables and that is what I listed above.The gun also came from the factory with a 23 series nozzle that threads on.I quoted the wrong part number above.The diffuser should be a 52 for using a 32 insulator.The 52FN is for the thread on 23 series nozzle....sorry.Or better yet get one of these,http://www.bernardwelds.com/centerfi...series-p151541and change to Bernard Centerfire......miles ahead of the old Tweco stuff.Last edited by vwguy3; 04-10-2013 at 08:49 AM.
Reply:Sorry if these are very overly simple questions.  Until now I was only familiar with the tip and nozzle.  I can't really picture in my head where the insulator fits in.  I'll have to take the gun apart later and check it out.Since I use .23 wire almost all of the time and weld on things between 24 gauge and 1/4", I would assume this means I would want the small?  If my welder is a lincoln sp250, would I go with the magnum 250?If so according to the chart I would need:  Adapter-1380005, Insulator-4323R, Gas diffuser-DS-1.  Then from the charts at the bottom (I'm not sure if I would need a tapered nozzle and tip or straight, so I assumed straight) Tip-T012, and Nozzle-NS-1218C (because I'd like to have 1/8 recess to keep me from burning the tip).Would I need to purchase all of these items?Thanks,Brandon
Reply:I got the same machine.  you are doing short circuit transfer you want the tip sticking out about an 1/8"    recessed is for Spray transfer and heavy material. are you sure you have solid steel wire and the ArCO2 options selected for "Process?Tiger Sales:  AHP Distributor    www.tigersalesco.comAHP200x; AHP 160ST; MM350P,  Spoolmatic 30A; Everlast PowerTig 185; Thermal Dynamics 60i plasma.  For Sale:  Cobra Mig 250 w/ Push-pull gun.  Lincoln Wirematic 250
Reply:Thanks for the reply.I do have the solid wire and ArCo2 selected.  Would it be possible to get the tip to be flush rather than an 1/8th inch out, or is the extended tip necessary?Thanks,Brandon
Reply:i have that welder also and the nozzle is a slip fit.you can slide it back until it's where you want it.miller thunderbolt 250vlincoln square wave tig 175 prolincoln idealarc mig sp250everlast tig 210EXTeverlast power plasma 50chicago electric (hf) 130 tig/90 arcchicago electric 90 amp flux wire3 sets oxy/acet
Reply:Originally Posted by Vetteman61Thanks for the reply.I do have the solid wire and ArCo2 selected.  Would it be possible to get the tip to be flush rather than an 1/8th inch out, or is the extended tip necessary?Thanks,Brandon
Reply:BTW what is the 4 or 5 digit machine code on yours and the Version (PC CHIP) number that shows when u turn it on ?  Make sure your machine is not part of the Capacitor bank recall!Last edited by soutthpaw; 04-10-2013 at 08:32 PM.Tiger Sales:  AHP Distributor    www.tigersalesco.comAHP200x; AHP 160ST; MM350P,  Spoolmatic 30A; Everlast PowerTig 185; Thermal Dynamics 60i plasma.  For Sale:  Cobra Mig 250 w/ Push-pull gun.  Lincoln Wirematic 250
Reply:The code number to look for is 9402. Then with the welder unplugged remove the covers.Check the screws that hold the caps to the buss bars. If hex head, caps have already been replaced. if #10 round head, Then you can take it to any shop that can do Lincoln warranties.It should be changed for free. The shop may try to rebuild your miggun or replace the work clamp to get your welder in top notch shape. your choice to have the extra work done that they will charge for.Any questions, tell them to look up service note 9302.A bad cap bank welds harsh and needs a very short stick out just to keep the arc going.A recessed tip will just pop and not want to start in this case.
Reply:Funny, I had the same problem for a long time. I was using tips and nozzles according to what my LWS recommended. The nozzles I got have a ridge that prevents them from sliding back any farther than what's shown in the op's photo. On a hunch I decided to trim the end off my nozzle with a hacksaw and filed it flat. What a difference!  The automatic settings on the SP250 finally started working for me, maybe a little too hot.