need a machinist or metal worker

Looking to permanently connect antique brass door knobs to brass back plate so they can be used as "dummy" door pulls.
Needs to be done without welding so I'm thinking a machinist could tool or connect them. Anyone have a recommendation or referral ?

i know some fellow artists who might be up for the task. but why no welding?

Subject: Metal worker referral

Ya, I thought welding shpuld work too, but I've spoken with metal-workers and they point out the heat from welding will damage and discolor the brass finish.
Do you know anyone who can figure out how to tread or machine someway of fastening the knob to the back plate?
I have two knobs and face plates I'd like to use as pulls for the interior front doors of a brownstone. Thanks!

There's a product called 'JB Weld' which is a two-part resin that bonds metal to metal and should do the job. Any decent hardware/ auto parts store should stock it - it's under $10.