Print PDF
Favorite
Email
Step 11Dimmer Control and Welding Thin Wall Tubing
The welder was too hot for thin-walled tubing frames, I kept melting holes even with the 1/16" 6013 rods. So I plugged the welder into a variac dimmer and turned the power down about 30%.
That gave me very fine control over power. Marc Lander and I did some very nice welds as seen here. After a few we got good enough to do the same welds with 3/32" 6013 rods and no dimmer and not burn holes.
More tricks - I used my left hand to feed a piece of mig welding wire into the weld to add more metal in and soak up the heat. Here's Marc doing that. Any wire is fine for this, coathangers are traditional for muffler work. Sand off the paint first if you don't like fumes.
Stopping to eat lunch helped a lot also. Your welds won't be good when you're shaky and tired.
I got my variac for free, don't buy one for this, they cost as much as a welder.
A solid-state dimmer that's rated for inductive loads does the same thing and costs a lot less.
If you're feeling particularly fancy, you can add in your own scr-based switching circuitry to vary the power, like this guy did.
That gave me very fine control over power. Marc Lander and I did some very nice welds as seen here. After a few we got good enough to do the same welds with 3/32" 6013 rods and no dimmer and not burn holes.
More tricks - I used my left hand to feed a piece of mig welding wire into the weld to add more metal in and soak up the heat. Here's Marc doing that. Any wire is fine for this, coathangers are traditional for muffler work. Sand off the paint first if you don't like fumes.
Stopping to eat lunch helped a lot also. Your welds won't be good when you're shaky and tired.
I got my variac for free, don't buy one for this, they cost as much as a welder.
A solid-state dimmer that's rated for inductive loads does the same thing and costs a lot less.
If you're feeling particularly fancy, you can add in your own scr-based switching circuitry to vary the power, like this guy did.
| « Previous Step | Download PDFView All Steps | Next Step » |
Pagano's hardware here on Alameda has lots of dimmers, but the ones that do inductive loads are $40 or so. The packages there say whether they are intended for inductive loads or not.
The box only goes to 15 amps and you will be blowing a lot of them at first. Probably run a 20 amp fuse with no problems. I ran a 30 @ 75% and it started to work properly, then the transistor in the box blew up. Upgrading this or decipating the heat from it will need to be done to go above 15 amp fuse safely. Also, one of the transformer secondaries smoldered, so I need to replace the wire or re-insulate it to have this welder work again. This was probably due to lack of proper heat decipation.
but nice work on the microwave oven conversion tho