TIG Welding Repair

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I bought an Eastwood TIG 200 AC/DC around the middle of December.  I've been renting argon, buying gas lenses, tungsten and filler metal and practicing.  My welds are not pretty but I feel the need to really melt in the metal for strength.  TIG seems like painting with steel.  It is so much more refined than MIG or stick.  DC TIG makes almost no sound at all.  AC welding on aluminum just makes a bit of a crackle.  With either there are no flying sparks at all.  If there are, I back off the pedal.  I learned to set the amps a little higher than needed then floor the pedal to get the puddle started, then back off as welding progresses so it won't get too hot.Project #1  Fixed this drill bit.  This is the first thing I ever TIG welded. Before welding I ground the two pieces to a point and filled the rootI learned a little about metal expansion.  This bit was bent after welding one side.  When I welded the other side the bit was straight and with very little runout.  I guess I was just lucky.  I decided to leave the bump for more strength.  If I need to grind it later, I will.  I drilled several holes through a 2X4 and pronounced it fixed. Project #2  Welded two bolt heads together to make an arbor for a builders level.I used no filler metal, just melted them together.  Looks pretty ugly now.  It seems very strong.  If I was to do it again I would add some filler.  I did learn I could bend it straight while it was red hot and had to be careful it didn't fall over while red hot.Here is the builders level on my tripod.  I got this on sale at a price too good to pass up because everyone is going to rotating laser levels, but this should work well for me for future construction projects.  I did not want to buy a surveyor's tripod (it would cost more than the level)so thought I could weld two bolts together to mount to a photo tripod I already had.Here is the arbor screwed into the builders level.  As an afterthought I realized I could have just used a 5/8” bolt 3” long with washer instead.  But then I wouldn't have been able to TIG weld it and the smaller bolt provides a finer thread for better tightening.  I still have to weld a few small bumps on the nut for finger tightening.  I think I will use bent finish nails.
Reply:Project # 3  Here is a gear from a pellet stove auger motor.  The output shaft had snapped so I welded it.  I used  the Eastwood TIG 200 AC/DC at 100A with 3/32 tungsten and large gas lens.  I found a gas lens works much better.  Before welding,I ground the output shaft almost to a point so I could get acceptable root penetration.  Every time I welded on this gear, oil came out of the gear; lots of oil.  I had to tack it and break it 3 times to get an acceptable alignment; oil came out each time.  It turned to carbon powder around the weld.  After welding, a file would not cut the weld.  I had to grind out the fillet to get clearance in the gearcase.The gear is from here.  The output shaft was grooved for a snap ring creating a weak spot where it broke.Here is the gear after a bit of grinding.  I had to grind much more than this to get the gear to fit in the case.  I had to remove the original 2 washers from this side and had to use a file with the gear in a drill press to remove the remainder of the fillet.  Picture showing shaft alignment.  I chucked the original shaft end in a drill press and ran it.  The two sides were parallel but the welded shaft was about 1mm off center.  I welded a bump onto the side of the shaft that needed it, then ground down the opposite side.  This re-centered the shaft in the bronze bushing. This is a one RPM motor so the gear shows almost no wear after 20 winters.  The shaft to bushing can have lots of freeplay with no problem and the motor floats so the slight shaft misalignment will not be a problem as well.  After reassembly, the pellet stove has operated for 24 hours with no shaft breakage.Now I am looking for something else to fix.  Any comments would be appreciated.
Reply:When welding DC you shouldn't have any sound and when welding AC it should sound like a quite yet pissed off bumble bee. I wouldn't put those welds under any kind of stress, but they should hold up. You seem to be very cold, so bump your machine up about 40 amps and learn to just lay that filler right in there.Sent from under a Miller welding helmet
Reply:Welding is fun isn't it!  Now get a lathe and really open up the things you can make/fix/do! Once a guy gets a welder and lathe/mill there is nearly nothing a guy can't make/fix.
Reply:Originally Posted by itslukedavisWhen welding DC you shouldn't have any sound and when welding AC it should sound like a quite yet pissed off bumble bee. I wouldn't put those welds under any kind of stress, but they should hold up. You seem to be very cold, so bump your machine up about 40 amps and learn to just lay that filler right in there.Sent from under a Miller welding helmet
Reply:Originally Posted by VPTWelding is fun isn't it!  Now get a lathe and really open up the things you can make/fix/do! Once a guy gets a welder and lathe/mill there is nearly nothing a guy can't make/fix.
Reply:The shaft diameter is about 3/8".  If I calculate the weld strength it should look like this:3/8" / 2 to get the radius. =.1875 inchThen    pi * r^2   =   0.1104 inch^2Filler rod is rated at 70K psi so lets say 50K psi for crappy welds.50K lbs/inch^2 * .1104 inch^2 =  5522 lbs.
Reply:Originally Posted by itslukedavis You seem to be very cold, so bump your machine up about 40 amps and learn to just lay that filler right in there.
Reply:Nice repairs. Your pellet stove repair reminded me of a fix I did for a friend late one COLD night a few weeks ago. His auger gearbox ate a gear. It would be a few days before the replacement arrive. So we whipped out a suitable replacement from a piece of scrap. I wasn't sure it would hold up but it ran fine. I only found the one photo on my phone of cutting the gear on the indexer.Not to hijack your thread. But, while I was looking for the gear photo I found another stove repair, for another friend, from the day before, that I had forgotten about. This was a fan hub repair. Once again, it was his only source of heat... so I fixed it rather than wait. The original hub was plastic and aluminum. It melted. The new one won't melt. Being able to fix stuff is a great life skill. Get your lathe out and have fun.
Reply:Originally Posted by forhireNice repairs. Your pellet stove repair reminded me of a fix I did for a friend late one COLD night a few weeks ago. His auger gearbox ate a gear. It would be a few days before the replacement arrive. So we whipped out a suitable replacement from a piece of scrap. I wasn't sure it would hold up but it ran fine. I only found the one photo on my phone of cutting the gear on the indexer.Not to hijack your thread. But, while I was looking for the gear photo I found another stove repair, for another friend, from the day before, that I had forgotten about. This was a fan hub repair. Once again, it was his only source of heat... so I fixed it rather than wait. The original hub was plastic and aluminum. It melted. The new one won't melt. Being able to fix stuff is a great life skill. Get your lathe out and have fun.