a couple of mig questions

[Highpower]

It kind of depends on what kind of 'tapered' nozzle you are talking about Vinn. If you have two nozzles like this, then you could use either one if you wanted to. Note that the "tapered" nozzle here has a smaller ID than the straight nozzle. The larger straight nozzles are for providing more gas coverage on higher amperage welders with a hotter arc. The smaller tapered nozzles are more common on smaller welders. One thing to look for is to make sure that when the nozzle is on the gun, that the end of the nozzle is even with the end of the contact tip that the wire comes out of. If the end of the contact tip sticks out slightly from the nozzle that is OK. You just don't want it recessed inside the end of the nozzle.

Now if you are talking about a plastic or bakelite "tapered" nozzle like this, that is for flux-core ONLY. That type of nozzle only keeps spatter off of your contact tip and gas adapter. It isn't made to have shielding gas flowing through it.

You don't adjust the pressure on a MIG machine, only the flow rate. Shielding gas normally runs at a non-adjustable static pressure through the regulator portion, and the FLOW rate is what is being adjusted on the gage dial. The actual pressure stays the same. I've never tried using a plain CO2 regulator for a Mig gun, and can't say if it would work or not. There are no normal pressure settings - only flow rates. 20cfh (cubic feet per hour) would be a good starting point for that.

.090 wire is WAY too big for that welder. .030 - .035 would do you just fine.