Cast Concrete With Fabric Texture

Make a panel of industrial concrete with a sensual surface taken from an existing or created textured material.

Step 1: Supplies + Equipment

Supplies:

Treated fabric or textured surface and plastic wrap to protect if so desired

Piece of .25" plexi as base at least 2" larger than your mold

Particle mask + gloves

Concrete mixture (I used Quickrete Anchoring Cement)

Scale or other measuring device

Plastic mixing container + strong utensil

Adjustable casting box mold + clamps

.25" grid hardware cloth 1"-1.5" smaller than final piece

Tin snips for cutting hardware cloth

Four .75" 10-24 screws + 8 nuts to match

Piece of .125" or .25" masonite for backing 1"-1.5" smaller than final piece (not shown)

Tiny amount of oil or acrylic paint (not shown)

Drill (hand or power) + drill bit larger than screws (not shown)

Braided picture hanging wire (not shown)

Step 2: Preparing the Base

Start with a fabric or texture of your choice (not thicker than .125” or the concrete will seep underneath). I created a furrowed surface by hand-manipulating satin as I fused it to a flat piece of muslin.

Set the fabric on top of the sheet of plexiglas. If you don’t want to get concrete on your fabric, protect it with a piece of saran wrap. Note: the saran wrap will result in a shiny surface. You can rough it up later on if desired.

Step 3: Preparing the Mold

In the supplies, I gave a link to the Adjustable Casting Box Mold. You can see in the pics that mine is a little simpler and works just as well. [I cut several 2" strips of .75" plywood from an old cabinet door and cut them to 16" lengths for the mold and 1" or 2" pieces for the clamp holds, which I simply nailed in.] Set up the mold to the size you want. Mine makes a 10” square. I use a triangle to make sure the corners are at right angles. I also put lines on my mold showing the depth I want to pour the concrete to. In this case I’m casting .5”.

Step 4: Preparing the Reinforcement

Cut a piece of .25” grid wire mesh, about 1”-1.5” smaller than your mold. This gives the concrete something to attach to and acts as a reinforcement.

To provide a means for hanging, I attach machine screws, holding them in place with nuts, into four spots on the mesh. I place them about 2” in from the corners.

Try to bend out any curves in the mesh so it is as flat as possible.

Step 5: Mixing the Concrete

Wear a particle mask and gloves. I always have my glasses on, but if you aren’t lucky enough to wear them, consider also wearing eye goggles (for the powder).

Measure the concrete. This requires some trials and note taking. The mixing ratio for the concrete I used (Quikrete Anchoring Cement) is 5 : 1, concrete to water. I used 4.16 lbs. of concrete with 13 oz. of water for .5” depth in a 10” square.

I use a food scale I found at the thrift store for measuring (and of course never use it for anything edible!). Place the measured concrete powder in a mixing container. With a stirring utensil at the ready (mine is a plastic rice paddle from the thrift store) dump in the water and stir vigorously until you get all powder mixed in and the lumps out. While it’s tempting to add more water, the thicker the mixture is, the stronger the concrete.

Step 6: Pouring the Concrete

Pour the concrete into your mold about half way, making sure it gets everywhere. Then insert the mesh piece with the screws posts facing up; continue to pour in the concrete to cover the mesh. It's best to work quickly as some concrete mixtures, like the one I used, can set within minutes. When the concrete is all in, adjust the screws in case they are not perpendicular. Ideally they should be at right angles to the concrete surface and all have the same amount exposed.

Let the concrete cure. To avoid cracking, you can cover the mold with a sheet of plastic. It can be handled in an hour or so, but it may take 2 or 3 days to fully set, during which time the color will change too.

Step 7: Attaching the Backing

Once the concrete has cured, release the mold. Label the top of the concrete (or orient it in some way). Put a little dab of oil or acrylic paint on the end of each screw. Take the piece of masonite for the backing and center it on the back of the concrete, resting on the screws so that the paint leaves a mark. Label the top of it also so you can reorient the parts later.

With pen or pencil make circles around the paint marks on the masonite and then wipe off the paint. Drill holes that will allow the screws to fit through. I used a .25” drill bit.

Reorient the masonite with the back of the concrete allowing the screws to come through the holes and hold it on with another set of nuts.

Step 8: Finishing

Cut a piece of braided picture hanging wire about 3" longer than the distance between the top two screws. Unscrew each slightly and slide the wire between the nut and the masonite, screwing the nut back down to hold the wire in place. Twist the loose ends of the wire into the remainder. Voilá, you may now hang your work of art.

You might consider coating the surface with an acrylic sealer. There are ones made specifically for concrete that absorb nicely. If anything looks too shiny, use a fine wire brush to scuff it up a bit.

Comments

[burton.kent]

"(not thicker than .125” or the concrete will seep underneath)" do you mean the concrete will seep under the edges of the mold? Because thinner cloth might have concrete seep through.

[kyle.kearson]

Really great! How do you "fuse" the satin to the muslin?

[jeanniel1]

Nice job! Might consider doing this for my clay work with slip, too!

[IngenuityAtWork]

Thanks for the info and the reply :-)

[TeresaM7]

This is wonderful! I'm wondering about doing something like this on a larger scale. Say, make this to fit my kitchen countertop (which reeks of 70's "everything must be YELLOW!" Yuck!), then coat the top with a clear silicone or something that would make it level and non-porous, keeping the beautiful texture but also a safe surface for cooking. Ooooooh! I like the idea!

[IngenuityAtWork]

Hi TerssaM7, There are probably two commonly available clear top coats available, epoxy/resin and polyester resin. I would recommend using the polyester resin, as it is prepared by adding a very small amount of hardener to the volume of polyester resin. Furthermore, the cure time can be greatly altered by changing the amount of hardener you use by as little as a couple of drops, which gives a nice measure of control and can help avoid problems like cracking. And since the consistency of the freshly mixed material is just slightly more viscous than water, it makes for much fewer problems with air bubbles. For an application like this you could apply several thin layers in the space of perhaps an hour. It cures up hard, crystal clear, and somewhat flexible, like plexiglass; pretty much a clear plastic. It can also be easily tooled or sanded if need be. I use it extensively to fill voids in wood in the furniture I build. I've found it to be much more user-friendly and to produce better results than epoxies. If you try it I'd love it if you posted a finished pic as a reply to this thread so I can see how it turned out; I'm planning to do this once I have a few of my pending custom builds out of the way, to make a (hopefully) really fascinating and nice coffee table top.

[TeresaM7]

Thank you, Ingenuity, that is wonderful information. It would be quite some time before I can get to this - too many NEED TO's to do before I can do something like this, but it's definitely a really beautiful idea. I'll definitely post a pic if I do it. Thanks again!

[IngenuityAtWork]

By the way, the polyester resin is commonly sold as "clear casting resin" at places like Hobby Lobby for about $20-30/quart, making it similarly priced or cheaper than epoxies. It's also a lot easier to mix and less messy in my opinion, and I think it makes less nasty fumes, although it's still woes not to breathe them.

[ooohlaa]

Really good job. I made some mosaic step stones with quickrete and I found that the gravel in the mixture was way too lumpy for fine work. I changed to portland cement/sand but just wondered if the one you used had big gravel components you had to pick out or was it smooth?

[vicmay]

The anchoring cement I used was perfectly smooth. I know what you mean about the gravel, though sometimes that can add an interesting touch.

[IngenuityAtWork]

Very cool project! Could you please add some details about your fabric selection, how you think various materials/textures/thicknesses, etc. would produce various results? Thank you!

[IngenuityAtWork]

And also some details on how you fuse the fabrics to each other and to the plexiglass mold base? Thanks again!

[vicmay]

Thanks! I happened to be some heavy satin around (scrounged) that I was playing with for something else, but actually I think its thickness was advantageous to create bulk to stand up to the concrete. A thinner fabric may not transmit the details as well, though one could always try. I do think coarser details translate better into the concrete.

To fuse the fabric, I used Wonder Web between the satin and a flat piece of muslin. I just put in small pieces of the fusible at a time so I didn't fuse everything at once in a configuration I didn't want!

I didn't fuse it to the plexi since I need to re-use that. I just laid it down w/the plastic wrap over it.

[rsfluffy]

Very nice! I wonder what it would take to make the panels? tile able. Hum, I'll get back to you. Again, nice work.

[vicmay]

Thanks! And yes, making them tile-able is something I'd like to explore too. It would be neat to have a few mold variations to create an interesting larger surface. Hopefully a future project.

[bittnerm]

very nice done

[studleylee]

Looks beautiful !!!

[PitStoP]

Looks great, nice texture. Maybe adding some acid stain or color stain to the mix to enhance the look even more. Thanks

[PitStoP]

I like how the texture looks.. It looks really good. You can stain it with acid to give it some color or just add color to the cement mix while mixing.

[TeresaM7]

This is wonderful! I'm wondering about doing something like this on a larger scale. Say, make this to fit my kitchen countertop (which reeks of 70's "everything must be YELLOW!" Yuck!), then coat the top with a clear silicone or something that would make it level and non-porous, keeping the beautiful texture but also a safe surface for cooking. Ooooooh! I like the idea!