Help with Lincoln SP-100 Welder

[Blazer]

Hi Everyone,

I am glad to have found this site, it has been an awesome resource for planning my son's kart. I am a relatively new welder, and have started to make an electric go kart for my son.

This is my first big project with the welder, and I am having some issues that I can't resolve. I am using a Lincoln SP-100 wire feed welder with the optional gas tank line. I am running a .023" wire with C02/Argon mix.

My problem is that the wire seems to get stuck/bind shortly after striking an arc. This often leads to a poor popping type of weld if not stopping completely. If I stop, and move the cable back and forth, the wire unsticks and begins to feed again. If I try to recreate the situation by bending the cable and pressing the trigger (while not welding) it will not bind or stick. This leads me to believe that the wire is sticking to the nozzle when it heats up. Sometimes I will notice a 1/2" section of the wire will be a silver color leading up into the nozzle after a weld. Consequently, the starting/stopping causes my welds to look terrible. Occasionally, I get lucky and get a nice smooth pass. What should I check for to get this running smoothly? The chart on my welder doesn't even account for .023" wire, so I am wondering if that is part of my problem. Thanks for your advice, it is greatly appreciated!

 

[Blazkowiez]

This may seem like a say response on a DIY forum, but do research in your town to find a good reliable welder repair store.

We use a hydraulic parts/welder repair store for any serious problem in the Century that sits in the garage at home. The last problem would've taken us hours and hours to track down in the wiring and if your shop is trustworthy they'll give you an affordable bill versus charging you for 5 parts that never needed to be repaired.

I hate the problem of finding a new shop, you almost need to take something into them the first time to see if they treat you honestly before returning to them time after time. It seems thats the way life goes but meh.

**My only suggestion would be replacing the tip with one of a higher quality. Cheap tips can lead to poor welds that sound similar to what you.**

*I highlighted the part that wasn't a stupid rant.*

 

[devino246]

What wire size did the welder call for? Id be willing to bet thats at least part of your problem. How much space are you leaving between the tip of the nozzle and the arc? You should have about 3/8".

 

[Blazer]

I just found a pdf manual for my welder, and .023" solid wire appears to be within spec for this welder. I did read that there are different sized nozzles for the various wire sizes. I will be sure to check that when I get back to the house. I have been running the wire speed at about 8.5 out of a maximum of 10. My wire stickout is usually right around 3/8" from the tip. My tip/gun assembly does look like it has seen better days. I will see if I can find a new assembly. What gas flow rate do most of you use? Thanks for your suggestions, I'll have to run this past my local welding shop this weekend.

 

[Doc Sprocket]

8 1/2 out of 10 wire speed? I'm quite sure that's far too fast...

 

[devino246]

That sounds wayy to fast. Mabe something around 6

 

[Blazer]

I had originally used a wire speed of a 6, and cranked it up further which seemed to smooth things out some. I have inspected my nozzle and found that the mig gun is from a much older style which doesn't use the conventional replacement diffusers/nozzles/tips. I disassembled the gun to clean it, and the plastic housing broke in half. The tip that is currently installed is way to large for the wire size. I decided to bite the bullet and install a new mig gun, and see if my results improve.