Gothic Trefoil

"OK", you say, what can I do with this?.

 

 

The name trefoil means three leaves. It was a common motif throughout Gothic art and architecture.  There a a number of variations,  It was squeezed into a triangular shape, and sometimes it was just inscribed into an Isosceles Triangle, or an Isosceles Triangle that had the two long sides bent out into a sort of pointed Gothic Arch.
They might have cut this in stained glass and put it into a round frame.  Clear glass with just the lead lines would be wonderful.  You could mount it to the inside of a round window  If it was hard to cut that center three lobed piece from a single pane of glass, they might continue the lines of the inner three circles to form overlapping petals, sort of like a curvy version of the Mercedes Benz star in the center.  The one piece then becomes only six pieces,plus the framing area, and much easier to cut out of glass.

I would also take a piece of mahogany plank(Mahogany is a very forgiving wood when you work on it and it lasts a long time in the weather.) or some other wood that could be soaked in preservative for a couple of days before using it on the house.
Thicken the lines a bit so that carving will be less delicate.
Transfer the pattern to your thicker than average board.
Drill a good sized hole in each void in the pattern.
Using a Jigsaw or a Scroll saw, and starting in the drilled holes, cut out the pattern.
Use a router to "mould" all the edges.  This means starting with just a bit of the blade digging into the wood and gradually extending the blade out more and more till your moulding is complete.
Soak the entire piece in preservative for a couple of days if using a normal wood.
Sand and paint to match your house trim.
Drill three holes into the outer frame of the carving at places that look appropriate to your pattern, and screw it to the face of your round window frame.
It could also be mounted inside the window to provide pattern for the inside.

If you are a good woodworker, make all of the wooden dividing bars much wider, say at least an inch and a half.  Then when the front mouldings have been completed, but not more than half the thickness of the wood, turn the piece over and rabbet out the back of each opening with a router, completing the areas that will not be reached by the router blade with a chisel(this is a very gentle operation with the wood on a flat stable base, and an extremely sharp chisel, so that the work does not put a ton of pressure on the wood.)  Rabbet the back in several passes of the router, taking out tiny amounts of wood in each pass till the required depth is reached.  Cut the rabbets to nearly reach the moulding on the front, then cut glass to fit each opening. Use Linseed oil, or some other recommended oil to moisturize the wood where the putty will adhere.  Allow to dry.   Run a tiny bit of glass putty in the rabbet in the groove of the rabbet, press the glass into it firmly, push in Glass Points to hold it, then fill the rabbet at a 45 degree angle with more putty.  Paint it all.

You could also draw a large triangle or curved Isosceles triangle on a piece of wood, the base of the triangle the same width as the top trim of your rectangular window frame. (See illustration, forgiving the sketchy look of it!)  Glue and tack a nice moulding like an Ogee onto the edge of the triangle, mitering at the corners.  You should be able to bend the moulding to the curve (if you have one) as it is not usually a drastic curve.  You may have to glue up several boards to get the width you want, but the glues these days are tremendous.  I was once told that if I do work with the modern glues, the wood would eventually rot away, and the glue would still be there on the house standing on its own!

Make a triangular piece of wood, no thicker than 3/4 inch or the projected thickness of your siding, to fit about half an inch inside the frame you have built.  Route the outside of the triangle with a nice moulded edge.

Increase the size of your trefoil pattern to fit within an inch or two inside the triangular board you have cut. 
Transfer and cut out the pattern voids like in the previous project.   Again, make all the slim pattern bars thicker, or just transfer the central three circle motif itself onto the triangle.  Cut it out, and mould it with the router in a simple pattern, even just a half round.
Glue and screw the cut out on to the surface of the triangular frame.  Use one of the great exterior wood glues now available.
Paint with several applications of preservative and paint when dry, or just paint if using cedar, Teak or Mahogany.

Mount this directly over the windows of the house, with flashing for the window under it, and flashing on top of the motif, (at least on the front of the house.) and apply siding around it.  Keep it well painted for permanence.  Lead is very flexible and easy to install on complex shapes.  Handle with gloves to avoid the lead on your skin.  You especially want to avoid it if it has a powdery coating or is very dull and whitish.

Use this or other related patterns to cut frames to attach to the front of rectangular casement window frames.  Screw them in place with Bronze or Stainless Steel screws, so that they can be easily removed for maintenance of the frame and the window.

It may seem like an awful expense to buy Mahogany or other exotic woods, but this will really MAKE the exterior design of your house, and will keep you from having to redo the work over and over.