Hi Guys
This is what I have planned
To mark the port light cut outs Ill use the outer rings and clamp them to a straight edge at the correct spacing and just turn the straight edge with the outer rings in place to mark both cabin sides.
I will use a spacer full length along the cabin sides internally as a spacer and set the protrusion so the retaining fly wire dimples as near flush with the out side of cabin sides so the inner ring will protrude slightly( the outer ring slides over the inner ring)
Thats the easy part.
Next is reducing the width of the outer rings which I do with a slitter blade on a 5 inch grinder . I can slide the outer rings on to the fitted port light while there being mounted to center them in the cut out before I cut the depth off outer rings and get a accurate depth measurement.
Using a timber space is out even with teak Ill have a problem I think.
So I am going to make stainless steel nuts out of flat bar that will fit flush inside the outer rings.
Then make a jig so I can screw the nuts onto the jig and make a accurate height measurement on all nuts before welding place the jig with the nuts onto the outer ring and weld them on.
The jig would be made so it centers the outer rings as well as locating the nuts to be welded.
The dry assemble every port light if they work out seal them in place probably some thing like urethane
any input taken on board
Or I just make my own outer rings out of flat stainless steel and tap blind threads