As it was.. a oxy acty barrel head tracer I made about 10-15 years ago.
New pattern arm, made from paintline track
Showing circle cutter being tested.
Eccentric used to rotate arms in circle, adjustable with threaded rod, slider, 1" sq tube.
Hydraulic rod from hyd cylinder, cut, center drilled, drilled and tapped for gear rack.
Plasma cutter, cut 1" tube, turned 1/2" rod, cut at angle, tig welded to split tube, hose clamped to tube.
RE NOTE, level everything with long level, the table, the mast the arm swivels, they should all be parallel to each other and the axis on the cutter center in vertical alignment of the tracer rod above, tracing rod should have a tip the width of the swarf cut out on the plasma cutter. Note the leveling feet on the mast head, the 8" circle leveled and welded to top of mast head, the pattern arm welded to circle.
I posted more pictures over on metalmeet.com in the free tools section, will add dimensions over there. Using, Lotos cut50d plasma cutter, cheap consumables.
Re: this project.. need to make a adapter for mustang transmission to chevy bellhousing.. cheaply.
This project is made from "crap".. get up off your butt and make something in the machine shop. Building handles so you don't need wrenches to move parts. Putting a 41 chevy window crank on the circle cutter..
Kinda tired tonight.. more tomorrow after Doc's wedding.. (biker wedding)