Fixing an inverter welder

Today while working on the rack closet the welder died on me for no apparent reason. But, after power off it made a couple of noises and the fan ran for a moment.

For being a Chinese machine it actually looks quite good and neat on the inside. The boards have conformal coating and just a tad of flux residue on some pads. The only thing out of place was a blob of solder on a header instead of a jumper.

I made a couple of measurements, the high voltage section was fine but the control supply was totally dead, except for a brief moment when turning off the main switch. Traced back from that board until finding a small block with a forward converter (kinda odd, I expected a flyback). The only component with bad readings was the recovery diode. I swapped in an UF4007 and at the next flick it was alive again.

Of all the things that could go wrong with a welder on novice hands this was not expected.

Door frame

The next step in the making of the rack closet is the front door frame. It’ll be screwed to the base and the top support. For that I’ll use some square tubing with a cap and nut welded to each end.

The lines scribed on those pieces look a lot like the iconic map of La Plata.

Each one was beveled and welded in the tubes. I ground the sides flat mostly for looks.

As I still had a while more with sunlight I used the support built earlier to keep them in place and tack everything together. Enough work for a Summer Friday.

Tacking door frame in place

Rack closet

So, after tearing down part of that wall we needed a safe way to store the equipment. It also has to be a bit above floor level, as we plan on making a small stage.

For the base I used some C channel iron. Parts of it were a bit mangled, so I made a makeshift tool with an hydraulic jack to spread its sides and have a good fit.

The top is simpler, it just needs to hold the vertical struts in place and the light fixture.

Then I centered it on the base and proceeded to punch and drill the holes to locate the rest of the structure:

Rack Closet: making the base


After making a lot of room on the shed I still had this feeling that the space was under utilized and I started to think of a small raised platform of sorts.

As luck would have it I had some leftovers of C channel from another project and they are perfect to make a frame and put some osb boards.

They are a bit cumbersome to handle by myself so I built a couple of hoists with some sheaves and scraps.

This proved to be extremely useful not only to lift but also to keep everything in place when drilling the wall.

It took a couple of days but I finally managed to make it with a bit of help from my dad.