An Experiment

After the first pass of shoveling part of the driveway (a snow blower is going to be necessary long-term) I returned to the house to try out a project.
The windows in this house are not great. Sure, they are double paned, but that means diddly when you can see daylight through the seams in the vinyl. I do not have money for all new windows at this point, and I haven't had the time to make exterior storms. I hate the window plastic sheeting because the double sided tape either leaves an awful sticky residue on the paint, or rips the paint off entirely.
I found these plans at the Island Institute website. I don't have a table saw to rip down 2x4's, so I wandered the molding section and came up with some small rectangular stock that I hoped would work.

Dining room will have to do for a shop.

I made the first one for the dining room window, since it's the easiest to access. Things I needed for this were: measuring tape, drill, handsaw, hair dryer, narrow wood, screws, wood glue, double sided tape, plastic shrink film, and some weatherstripping.
The small stock was good, because it flexed a little to accommodate these not-square windows. But the problem was it flexed over long spans, just under the pressure of the plastic film, bowing it in from the edges.

You can see the bow at the top of this on in the dining room.

I had enough material to make a larger one for the room I'm using as a bedroom.

The center is offset to allow for the screws. Should have just been a through pin.
I measured half a dozen times, and there's still a gap at the top.

So things I learned -
A) These aren't that hard to make, but I need bigger stock (and a better place to work.) There's only one screw in each joint, and that make it so that everything wanted to spin.
B) These can't be made too tight - they need wiggle room to get in. There's where the foam weatherstripping comes in to take up the gap. (Though not as big a gap as I somehow wound up with on the second one.)

I'm pleased that these could be removed and reused, rather than all that plastic sheeting winding up in a landfill.