Which transformer project?

Yes appears to have a magnetic shunt, That may be OK for a ordinary Arc Welder, If a spot welder is intended, then you could look for a junked micro wave TFMR , these also have a shunt but can work OK just by punching the shunt out, and winding a LV secondary.
What type are you intending to build?

rjenkinsgb said:

That looks suspiciously like a "Constant voltage" (ferro resonant) transformer, a very specialised type of transformer, that's probably not suitable for any other use?

It may not be, but that construction style is quite unusual and distinctive?

eg.

Welcome to Shape, LLC - Ferro-resonant/(Constant Voltage)

Global provider of specialty ferroresonant transformers, including Constant Voltage Normal (CVN) and Constant Voltage Sinusoidal (CVS) transformers.

www.shapellc.com

Ferroresonant Transformers - Magnetic Specialties, Inc

Ferroresonant Transformers are also known as Constant-Voltage Transformers (CVT). A CVT regulates its secondary voltage typically within a few percent.

magspecinc.com

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You're right on the money actually, thank you very much for clearing that up for me...

MaxHeadRoom78 said:

Yes appears to have a magnetic shunt, That may be OK for a ordinary Arc Welder, If a spot welder is intended, then you could look for a junked micro wave TFMR , these also have a shunt but can work OK just by punching the shunt out, and winding a LV secondary.
What type are you intending to build?

Click to expand...

I am still doing more research on it to see all of the possibilities that may be available to me. Being able to continue projects I regularly would have to stop because of the weld issue is my main reason for choosing that. Although I think I have seen somewhere about a smelter/ furnace to melt metals so I'll see what its more suitable for. Thanks ! If I do decide on something I'll be sure to share the end result.