Poured Concrete Picture Frame

Some ideas are so stupid you just have to try them out, right?

We recently acquired a whimsical yet edgy drawing from acclaimed New York artist Glenn Palmer-Smith.  The theme is Russian, and although I have made many picture frames over the years, I felt this piece called for something special.  When I thought about Russia, the stark concrete architecture from the Soviet era came to mind, so a frame with the same look seemed just right.

Illustration (1) is a cross section of the form I had to build.  I decided on a frame width of 2 1/2" and a depth of 1 1/2".  I also bought a pre-cut piece of glass which closely matched the size of the drawing -- 16" X 24".  I bought a pre-cut piece of 1/2 " birch plywood to use as a backing for the form.  I had a few odds and ends of 2 x 4s around from which all of the other form materials were made from (table saw needed).

On Illustration (2) you see strips ripped to 1" x 1" and nailed in place on the back-board.  The dimension of the outer edge of these strips is the inside dimension of the picture frame.  Since the glass and artwork were 18" x 24" the outer dimensions of these pieces is 17" x 23" to allow for a 1/2" inset all around for mounting the glass and artwork from the back.  I went to the trouble of mitering the corners so the form would be smooth all the way into the inside corners.

Illustration (3) shows the outer sides of the form installed.  The distance between the outer and inner form walls is 2 1/2".  Also shown is the first of four strips which were screwed in place -- these pieces  provide the form inset for the 1/2" x 1/2" rear groove where the glass and artwork will go.

Of course, I was thinking about how I would hang this expectedly heavy frame, so I decided to imbed two keystone shaped strips in the concrete which would provide a place to install the screw-eyes and wire hanger.  These strips are shown in Illustration (4), along with their "bridge" pieces -- and of course these all have to be installed with screws too.

As with some old concrete buildings, I felt a little hint of rebar in the final product might enhance its character, so I bent and dropped four pieces of rebar into the form prior to pouring.  See Illustration (5).  I also coated the wood form with wax to hopefully help the frame come out of the form later.  It probably would have been a good idea to build it entirely with screws rather than nails like I did.

I really didn't want to have any stones getting in the way so I selected extra strength construction grout for the mix.  This stuff is used for heavy duty machinery pads and the like, so I felt it would have plenty of strength -- with the rebar installed of course.  See Illustration (6).

While pouring, I used some extra care to try and make sure the grout was filling the space under the edge of the inset strips.  After most of the form was filled, I installed the dovetailed hanging strips, as per Illustration (7).

I used a good soupy mix, and when the form was full of grout, I went all around hitting the form with a hammer, and finally resorted to holding an oscillating sander hard against the edges to "shake" the whole box and help make the grout fill all the spaces.  I did see quite a few bubbles of air coming out during this process.  I left it to cure looking like Illustration (8).

After a week, I proceeded to see if I could get the frame out of the form.  First the hanging strip bridges were removed (Illustration (9)) and then I pried out the inset frame.  Those strips were a little wider than the inner frame so I could use a claw hammer to pull them up -- Illustration (10).

I turned the whole works upside down and worked my way around the frame tapping upwards on the form with a hammer (Illustration (11)), and sure enough, the form came loose (Illustration (12)).

I washed the frame with muriatic acid to neutralize the alkalinity, and there were a few places where I could see a hint on the rebar just under the surface.  Since I wanted a bit of this to show, I chipped away lightly at these areas and used a high pressure air hose, which also blew away some minor imperfections. 

You can see these imperfections in Illustration (13), which also shows the use of paste wax to seal the cement and provide a slightly richer color.

It was obvious from the start that the usual nails or glazing points you might use to install the picture in a wooden frame wouldn't work here, so after finding a slightly warped piece of 1/4" plywood, I installed the glass, drawing, extra piece of art paper, and the plywood, clamping everything in place and sealing it all together with building cement (Illustration 14)).  After the clamps were removed, I also sealed the gaps.  Here in Florida tiny insects somehow find their way inside picture frames but I think they will have a difficult time with this framing job. 

Can anyone guess the title of the drawing?