Occasionally, when I'm MIGing I get the 'sizzling bacon' sound for 3 seconds, then a light hissing sound for 3 seconds, then back to the 'sizzling bacon' sound, then the cycle repeats. Any ideas why I'm getting the hissing sound? The weld and penetration seem pretty good. Here's a pic. Specs: Hobart 220v with a 75/25 mix. Gas flow is 28 psi, no wind. .035 wire. 3/16" plate welding to .120 wall tubing. Voltage is 4 (on a scale of 6). Wire feed is 52 (on a scale of 100). All metal is ground clean. I swap tips way too often! All equipment and materials are kept clean.
My guess would be inconsistent wire speed. Open the machine, and watch the feed and wire. Clean your liner, and drive wheels. You can also cut the wire and pull it through the cable to see if it pulls smooth.
A few thoughts..... I know that Hobart is Miller's long distant cousin, but a Miller just behaves itself and other welders don't. Also, you state that the metal is ground clean, yet the picture shows rust pitted steel. Are you keeping a consistent angle and distance of cup to metal?
Your liner is probably dirty or your wire roll is getting some surface rust. Also I would cut the gas down to around 15PSI.
Inconsistent wire speed would be my first guess too. That can be caused by a few different things. All easily fixed My next guess would be power out put of the machine . Complicated Third guess would be power input to the machine surging _ your lights would be surging slightly at the same. Problem is you can't watch the lights and weld too. Electrician or power company
Definitely wire speed, it's trying to ball up on the end of the wire. I run into the same thing sometimes, if the wire speed is too slow, it'll pop and crack and run up to the tip of the gun, then the wire shoots back out and makes connection and it pops and cracks and runs back up to the gun tip, and over and over.
We just had a similar problem with a brand new Miller 350P. It turned out to be a bit of interference on the shaft the wire spool rides on. It would move freely for most of the rotation, then hang up a bit for the rest. As mentioned, check to make sure your wire is feeding consistently. If not, check you feed wheel tension and anything else to do with the wire being fed to the tip. Also, make sure you don't have any tight radii on your mig gun and cable. We had a Miller 250 that wouldn't feed very well if the gun and cable weren't almost perfectly straight.
Cut and pull the wire. (don't let go of the spool end!) Pay attention to how the wire pulls and if it gets smoother or rougher at any point. I take out the tip first. Slide that on a good section of wire, and make sure it moves freely. You can clean the liner with LOW pressure compressed air. If you blow it out to fast or hard you can plug it up completely. ( You can also use computer cleaner in a can) Then re feed the wire, put the tip on and adjust the feed tension. You can also clip the wire again and pull it out to check if cleaning the liner helped. Too adjust the tension, set the wire speed mid range. loosen the adjuster, trigger the wire. tighten if it's not feeding wire. As it feeds, press on it from the side an inch or so from the tip. You should be able to deflect the wire to a 45 degree angle without the feeding slowing down, but the tension on the adjuster should be light enough to let the wire slip if you push the wire more than that.
One possibility also is cheap wire …. Inconsistency’s in the wire could effect the speed / drive slips in sections of the roll. Definitely a speed issue.
Yep! I see it balling up on the end while I'm welding then it runs up to the tip then shoots back out. I guess I'll clean the liner, refeed the wire and adjust the tension too. Many thanks!
Poor ground can cause this on a mig unit. The machine doesn't know or care whether the ground is good or bad, it just keeps feeding wire, and momentary interruptions in the ground interrupt the arc for a split second giving the same results as inconsistent wire speed. Saw a video on this by Jody Collier on his site about welding tips and tricks. I'm gonna get me one of those all copper groud clamps if I can find one for a reasonable onrice.
The first three things I would trouble shoot are the liner, the drive roll tension, and the contact tip. Is your gun lead straight or is the cable crossed, sometimes this builds drag on the liner. Another thing to check is that your wire spool isn't crossed over, meaning that the wire is feeding from the bottom of the spool and not from a layer or two down. Usually its the liner or the contact tip, but your drive rolls may be slipping or worn out so check the tension.
It definitely sounds like a feed problem. Do what all the others have said first. One thing I have seen on some machines is that the upper roller carrier is made of some sort of plastic. If that is the case, release the tension on the drive rolls after every use. I have seen the plastic deform over time if left engaged and drive roll tension change.
UPDATE: Installed a new spool of wire, blew out the liner and generally cleaned up the inside of the welder. Now I have a smooth feed, sizzling bacon and tasty welds! Thanks HAMBers!!
Remember, don't roll up the gun/feed line real tight, it'll end up cracking and you'll have to buy a new one. I only roll mine over the bottle and back down, minimizing a tight coil!
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