@ BrownPigs
I've been making casting spoons and spinner blades from sheet metal for almost 20 years now , so I don't see any reason , why it should not be possible to make "jitterbug" lips in the same manner as well !
I haven't yet tried it for one major reason which is the line tie intergrated on top of the lip ,....... it would take a special rigid metal alloy to render this line tie sufficiently rigid against bending and also the entire lip twisting within .The lip has to be quite light in weight , so I would furnish it from 0,5mm thick stainless steel sheet or 1,0mm aluminium sheet , .......both of these materials , that are easily accessible to me , would certainly not fulfill my demands in terms of stability of the intergrated line tie .
I have made some jtterbug style lures with commercially available lips of different sizes and weights , these lips were not much thicker than I would make them , but they were a lot more rigid in terms od bending and twisting within than I could make them with my materials .
These lips were not that expensive , so I haven't bothered to try to make my own , .......but it definately is possible !
You need to make a plane marker template at first to mark the outline of the lip on your sheet metal , drive around it with a marker needle or a thin permanent felt pen .
Cut out the rough outline with shears , ordinary ones should do with the above mentioned materials , for more rigid sheets it requires bench shears , .............but the small latch of the intergrated line tie and the indention between the two wings of lip at bottom would give you problems cutting with shears , might as well use a metal bladed jigsaw for those details .
Afterwards you need to grind and file the outline to final shape and accuracy , break all edges thoroughly .
Make yourself a beating template of hardwood , utilize your lip template again for the outline and take a small round chisel and/or "Dremel"with oval router bits and gouge out the lips cupping curve in the hardwood , smoothen that indention as good as possible .
Now utilize a small plastic hammer to beat your lip cut-out flush into the indention of your hardwood template to achieve the initial cupping of the lip .
After you might use a small ball peen hammer to achieve sharper and/or deeper cupping portions .
Now your cupped lip would look rather ugly with plenty of bumps and blemishes on it and you'd want to smoothen it's surface .
You would do that with your small ball peen hammer on a rigid and plain steel plate/anvil or similar , place your lip onto the surface and constantly hit the cuppings inside(exactly where the lip contacts the plate) with the hammer , a change of the angle , that you hold the lip onto the plate does alter the grade and direction of the cupping ,..........takes a bit of practice , but it definately works , ........the more often you'd hit the lip with the hammer , the smoother the surface would become .
After you're finally satisfied with the looks and cupping of your lip , mark line tie and screw holes with a felt pen(you could have done that from the start as well , but mark the holes with a center punch not to loose the location whilst doing the cupping work), mark with a 90° center punch , so that your drill bits find instant grip and drill through , also carefully break the edges of the holes afterwards with a 90° countersunk or a bigger drill bit !
Mark and drill from the inside of the cupping , virtually the front of the lip , .........hold with one hand onto a scrap piece of wood on your drill press ans drill through .
Good luck , diemai