</font><font color="blue" class="small">( How about the wire on the mig welders. Do you have to keep them dry too. )</font>
Generally a good idea - otherwise the wire corrodes (even though it's coated.) If I'm not going to welding for awhile I usually will pull the spool and bring it in the house (welder is in a mostly unheated garage) Having said that, I have heated up the garage in winter when it was very wet out and had condensation form on the wire while the spool was in the machine. Other than having to jack up the pressure on the drive rolls to avoid slippage it wasn't a problem.
</font><font color="blue" class="small">( I was at the end of my spool the other day and tack welded a nut to a plate with my mig and later hammered it off and the metal in the weld puddle was very pourous and appeared soft. )</font>
If it was MIG check to make sure you had your shielding gas turned on. If it was on, was there anything you were doing as far as holding the gun at an odd angle so the shield was being blown off ?