How to adjust tension roller

[pavetim]

Ok the manual says snug up the tension roller knurl knob but they have numbers on it. So how exactly to you adjust it? I-Mig 140E

[Rambozo]

Ok the manual says snug up the tension roller knurl knob but they have numbers on it. So how exactly to you adjust it? I-Mig 140E

Tight enough that the wire does't slip while welding. For solid wire MIG you can have it pretty tight with no big problems. With flux core, if it's too tight the wire will get messed up and not feed well. But too much tension is hard on the machine, so you want just enough that it doesn't slip.
Look on WeldingTIpsAndTricks.com and check out the section on MIG tips. You will learn a lot. Specifically look for the curl test. That will show you how to adjust your tension setting by holding the gun up to a piece of wood and seeing how the wire curls without slipping in the rollers.