Month: February 2009

laser welding: micro fabrication: plasma nozzle

The largest outside diameter is 3/16” (just under 5mm). The weld is about 0.02” wide (½ mm). You can see my grubby finger under the assembly for a sense of scale. The material is 17-4 PH stainless steel, welded to nickel plated 304 stainless steel tubing.

laser welding: micro fabrication: miniature gear assembly

The gear is 0.25″ diameter (6.25mm).
The material is 17-4 PH stainless steel.

laser welding: mold repair: worn core pins

The cores have worn in the corners and are flashing during molding. The repair must not gouge the corners of the existing part, and must be built up enough for refinishing. The material is P20 mold steel.

laser welding: mold repair: machining mistake

The corner was gouged with a cutter during rough machining. The repair must completely fill this large defect, but the heat of welding cannot be allowed to distort the part and shouldn’t disrupt the copper plug that seals a waterline in this part.

The material is 420M stainless at 52 RC.

This is about as big a weld volume as can be conveniently handled by laser micro welding. Bigger weld areas are better handled with TIG, but at the risk that the part will distort.

It is possible to do the rough welding using TIG and manage areas of distortion afterward, with the laser welder.

1. TOP VIEW: Note the huge number of individual welds required to fill this defect. (Each hemispherical mark you see, is formed by a discrete weld deposit using a 0.015” diameter 420 M stainless welding wire under argon gas coverage).

2. SIDE VIEW: The weld is about 4 layers deep at its thickest.

3. AFTER MACHINING: some defects are still visible and will be corrected by spot weld placement.


5. FINAL FINISHING: At approximately 40X magnification, the defect is barely discernable, and is completely invisible to the naked eye.

laser welding: mold repair: changing engraving

The engraving was changed per customer request.

The surface geometry to enable re-machining the insert was not available, therefore the welding needed to be delicate, allowing it to be re-finished using only polishing stones. On the left side, a logo has already been welded and hand stoned to 600 stone finish.

1. The lettering is approximately 1/8” (3.2mm) tall. The welds stand proud of the surface less than 0.003” (0.1mm). The material is P20 mold steel.

2. A DETAIL SHOT: (From another insert with slightly larger letters)


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