[bosulli]

Just bought a used Miller Bobcat 225 with a high frequency add-on in hopes of learning how to TIG. I watched all the You Tube videos I could find, and understand the generic TIG machine controls. Got the TIG up and going today for first time. Left the HF setting at 60, but had trouble with unit coming on or turning off with certain combinations of the other controls.

Need some help with the panel switches. I don't have a foot pedal, but there is a wheel knob on the torch handle (see photo). When the 'SLECTOR' switch is set to panel. seems I can't get an arc. On 'PANEL' I seem to get an arc. Why?

The one that really has me befuddled is the 'START' switch. I would think the START would be so the HF works to help start the arc. OFF would mean that its bypassing the HF??? 'CONTINUOUS' I have no idea about.

[Artie F. Emm]

Miller offers user manuals for various models, here:
https://www.millerwelds.com/support/manuals-and-parts

You can enter by serial number or model name. A read of the manual will likely get you further down the road.

[Braehill]

bosulli,
First off, welcome to the forum.

Miller uses the terms "Panel" and "Remote" on most of their controls and in this case the HF will be present at the torch when it's switched to "Panel" and operated with either a foot or hand control when switched to "Remote". On a remote ampetrol (hand or foot) there's a switch to start the arc and then the amperage is controlled as you move though it's range.

Set to the start position, the HF should stop while you're welding and only re-initiate when it senses the arc has extinguished and it tries to reestablish itself. If you get close enough to the part the spark will light off when set in "Start". Continuous is for welding on AC while welding Aluminum or a few other metals that require a HF overlay to be welded on AC polarity.

Not sure if the Bobcat can weld both AC or DC, but if it can, all the better. You'll have a pretty versatile machine either way. If it's just a DC machine you can weld almost anything except Aluminum.

Len
P.S. For some reason I can't see the photo that you included.