Cast Iron Repair

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OK smart ones, I just weld for fun and I have been doing some reading on here and wondered if TIG brazing might be an appropriate repair process for filling in the groves on my Powermatic belt sander. If it is a good process for this can I use my Maxstar 140 for this? DC only? It seems 45 years in a school wood shop is too much to take. Here are the pictures of the arm needing repair, the one groove is pretty deep Attached Images“Life is not a journey to the grave with intentions of arriving safely in a pretty well-preserved body, but rather to skid in broadside, thoroughly used up, totally worn out and loudly proclaiming ... WOW! What a ride!”
Reply:TIG brazing would do just fine, and all that is required is low amperage DC current.
Reply:Well I did it, I ran up to the welding shop and bought some silicon bronze rod and plugged in the tig welder, it turned out pretty good but it didn't flow like it does with oxy-acetylene, it kind of balled up but seemed to stick pretty good. This was my first ever attempt at it and it seemed to get easier as I went. Tell me what I did wrong or did right, thanks Attached Images“Life is not a journey to the grave with intentions of arriving safely in a pretty well-preserved body, but rather to skid in broadside, thoroughly used up, totally worn out and loudly proclaiming ... WOW! What a ride!”
Reply:Regardless of all the low amperage info I found I guess I needed more amps, I was using 40-50 amp but I think I needed more.“Life is not a journey to the grave with intentions of arriving safely in a pretty well-preserved body, but rather to skid in broadside, thoroughly used up, totally worn out and loudly proclaiming ... WOW! What a ride!”
Reply:If it's balling up, you're not hot enough for it to wet out properly.  It also looks like you have a lot of surface contamination.  Consider baking it with the torch prior to tig brazing to burn out any oil or dirt in the area to be brazed.
Reply:When tig brazing you have to strike your arc and just heat up the metal a bit then get the rod under there and melt a ball off under your arc. Keep your arc on the bronze till it wets out, it go from ball to puddle pretty quick. Then keep your arc only on the bronze and travel while adding filler as you would normally weld. You use the heated bronze to heat the surrounding metal instead of the normal torch which heats the surrounding metal which makes rod melt. You do have to watch so you don't use to much heat with arc that you start melting everything together and get a diluted weld bead instead of brazed area.Millermatic 252Lincoln 175 plusTA 185tswTA 161stlhypertherm pmax 45Victor torchHenrob torchAn S10 for each day of the week
Reply:Dear Sir look like the repair turned out fine,you lucked out,did it crack?If t were me i woul have pre heated it to around 400-500 degrees&got after it,then put it back on the fire/heater &let it do out/cool down gradually to room temp.jus rember when welding cast got to phe heat ,weldTHEN slowle cool down lgad to see all went well for you