Guys wire feed welders feed wire, and it's important they do so smoothly & reliably. One of the great shortcomings of the inexpensive Chinese wire feeders is that the motor and drive rollers aren't nearly up to par with the high quality wire feeders, but they work quite well and last longer if the wire feed is adjusted properly. This is a simple and quick setup that becomes intuitive after a couple of tries. Before taking the factory wrap off the new spool and I suggest starting with one pound spools and yes there is a reason for this, explain later. Make sure the machine is both off and unplugged before starting. Check to see that the wire drive roller setup is the same size as the wire you're installing. There are two grooves in the wire drive roller the wider of the two is for .035 or metric equivalent & the size should be stamped on both sides of the roller...you can see the difference. Here's a hinky detail, one groove may be cross hatched rather than smooth inside the groove, this is the flux core groove for all wire sizes. The problem is it usually only works well with one or two sizes of wire...go figure. The drive roller just pulls off it's axle after the retaining nut is removed and then reinstalled with the best option groove lined up with the liner and wire clamp mech. This clamp mech is spring loaded and releases when you gently pull up the adjustment knob and gently swivel the knob towards yourself. This takes the drive pressure off the roller and allows you to pull any wire left in the machine to be pulled out of the liner, always remove wire from the tip end with pliers and machine off. Now open the fresh wire packaging being very careful to not birds nest the spool as you mount the wire to the machine, it's a two hand operation YOU'LL DISCOVER AFTER YOU MESS UP AND HAVE TO REWIND many feet of wire. Wire feeds off the top of the installed spool and lines up best this way, not like toilet tissue, it really matters how the spool is installed. The wire end should be a really clean cut and the first foot or so of wire should be straightened since it wants to curl back to the shape of the roll it's been stored on. A kinked wire can catch on the liner and if it does you'll have to hand wind the wire back out and do it right. The gun liner should be straight and not curled along it's length as well and for the same reason. After you get a couple of feet of wire in the liner secure the line clamp on the wire and make sure the spool nut has just enough pressure to keep the spool on the machine and spool freely, no resistance. Wire tension is now controlled only by the amount of tension placed on the wire tension roller to drive mech. With a fresh tip of proper size installed for flux core, which can be the exact size of the wire used, but often flux core runs better with next size up tip. .030 may run better with .035 tip installed, Wire brand, tips and machines vary. It's trial and error; learn what works and stay with it. Plug the machine in & turn on. now using the gun trigger feed the wire at low speed through the liner till the wire it clears the tip, if the wire hangs up at the tip turn the machine off and remove the tip, turn back on and use the machine to feed the wire clear of the liner just enough to, after turning off the machine, install the wire through the tip and screw the tip back onto the gun diffuser assembly. At this point you should be able to pull the wire with just a few ponds of pressure through the tip using pliers. If it's too easy or too hard to pull the wire then your drive clamp pressure needs adjusting, less pressure on the roller and the machine slips on the wire and performance will be crappy or it won't feed at all. Too much pressure will eventually burn out the drive motor. Adjustment is made with the knob on the drive clamp. Several ways to test drive pressure the way I described has served me well over several decades of use, but the others work as well or better?
Setup is critical to good welding. Use good wire and tips. If you weld often or have a big job buy good wire on the 5 lb. spool; it works great on these small machines and saves a lot of money per pound, but if you only have use for a welder on rare occasions go one pound, because old wire mig or flux goes bad with time and should be replaced...high humidity areas are especially bad as are shops where heat is used when occupied, but turned off when you leave. If you cover your machine use a cover that can breathe. Also tips that look good after running a good amount of wire may not be. Out of the blue, erratic welding is quite often due to a bad tip, or a poor work clamp connection or both combined. Address these first before trying to rebuild or adjust everything. Make sure the machine is setup correctly has the correct, fresh consumables in place then the welder only has himself to look at when welds are of less than decent quality, use good technique pull wire with flux in all positions, on all joints and work clean on joints that have appropriate fit ups and spacing. The easiest position to weld in is comfortable and most commonly flat and with great lighting. It's quite uncomfortable to weld upside down and in the dark, though it's well done by some pros, but even the best do better under great conditions so set up both machine and yourself for success every time you prepare to strike an arc.
This would be a full 40 hrs. of training in the shop for newbies under drill instructor supervision and the pressure of your first pay check being also ones final pay check, so be patient with this.
Rick C.