Good Evening, been busy all day TIG welding boiler pieces together. For those of you that are not familiar with TIG welding, let me give a brief explanation. TIG stands for "tungsten inert gas".
Picture #1 shows a typical TIG torch head. The handle and head portion is water cooled. The pink colored item is a ceramic cone or nozzle. There is a tungsten electrode with a sharp point barely sticking out of the nozzle. The work piece is grounded as in any typical welding process. When you activate the foot pedal to start the welding process, argon gas starts to flow and floods the immediate area to be welded. Then the current is applied to the electrode generating a plasma arc. As the current is increased the metal starts to melt and pool very much like when soldering with a tin/lead solder. There is two basic processes in TIG welding. The first is fusion welding. This is when you melt the metal of the pieces you want to join together without any filler material. The second process is a fillet weld. Same process as the first one mentioned but a filler material is added to the pool that has been generated to increase the amount of material at the weld joint. There is no smoke, splatter, scale or fumes generated with TIG welding. It is a very controlled and clean process and you can see what is taking place all during the process.
OK, on with the build; Picture #2 shows the pieces for the fire box entrance way. Beside the pieces is a "slugger cutter". It is the same diameter as the outside radius of the firebox entrance pieces. I will use the slugger cutter to make the penetration into the outer boiler shell and firebox. I will post some pictures of this process later.
Picture #3 shows the pieces mentioned earlier tack welded together. Again, all I had to do was to place the tungsten electrode over the joint and apply the current. Both side melted together.
Picture #4 shows the beginning of what I call the 'root" weld. This is a fusion weld as described earlier. After the work piece cools, I will come back and add filler material to complete the welds.
Continued to next posting.