1/2" OD Square Tube Coupler/connector/corner for cold frame
I've picked up a fair amount of 1/2" square tube that's used in closet systems - supporting the wire shelves.
I'm looking for some connectors so i can make some frames. the link below is a coupler for round tube, but i've got square tube pictured in the link above.
I' making some cold frames and will attach single pane glass panels, or some opaque corrugated plastic (just like cardboard, but its semi-transparent plastic). I don't have a welder so i can't weld the frames together. I'd like to get some 3-way connectors so i can connect a vertical piece and two lateral pieces to make something like this:
or even something like this:
i also would like to have something like this swivel connector to use for the opening top window portion:
I can't seem to find any square tube couplers/connectors anywhere on the web (except for some that are in the UK) that are less than $5-$10 each.
Has anyone else had a similar need, or know of a solution?
if i made the drawings in ketchup, could someone reading this post 3-D print them for me to test/prototype???