I'm assuming that this is a link then, and I cannot ask a question,......but just in case....See http://www.chaski.org/homemachinist/viewtopic.php?t=38727 for some help with your problem...
Ken_m » posted...
"The problem you are encountering is very common. The cause of this is when welding relatively "dirty" carbons steels (compared to alloys ) you need need cleaning agents in the weld. Hot rolled sheet is the worst
Because with TIG , the process itself does not really provide any cleaning, you must rely on the filler material to clean the weld
The most common cause for this is people using AWS R45 and AWS R60 carbon steel filler. This stuff is actually for oxy acetylene gas welding. You can't tell the diffrence at first glance when looking at it
The proper filler choice for unalloyed carbon steel ( mild steel ) is AWS ER70-S2 . The "S-2" filler is also refereed to as "triple deoxidized" because it has Ti, Al ,Zr . It also has Si and Mg which are common deoxidizers is MIG wires
A distant second choice is ER70-S-6 ( very common in MIG wire form ). This filler uses Si and Mg as primary deoxidizers
Quality filler will always be stamped / coined on both ends showing AWS Class
Lastly, if you are trying to do a pure fusion weld without filler on carbon steel, the only way to minimize the pinholes is to minimize the depth of penetration, which means go easy on the current. Don't be surprised if you can't get rid if the pinholes when doing pure fusion welds (without filler ) on carbon steels
You can get away with using the cheap oxy filler if you get lucky and the base material chemistry is relatively low in trace contaminants. Having said that, since you don't use much filler TIG welding there is no reason to be saving money by buying the less expensive filler
If you use only ER70S-2 you won't have any problems
Hope this helps"
If I try to clean the pinhole area what do I clean it with? And,..will adding filler rod ( or mig wire....I got buttloads of that) fix this?