Concrete Cathedral Night Light

Intro: Concrete Cathedral Night Light

I have always admired the Gothic Cathedral and architecture in the renaissance age. a lot of the buildings were constructed with bricks and stones and they are still dominating the city skyline of some of the famous European cities. When my wife and I traveled to Italy last winter to visit the famous landmarks, we were both amazed by the craftsmanship and the durability of those ancient structures. I made this miniature night lamp, that can be placed on the floor or in a bookshelf. the ambient light brings a warm and mysterious light into the study or sitting area. concrete is a very durable material, it is relatively easy to work with. and the aesthetic of the rough concrete finishes somewhat resemble the ruins of the ancient building. the build is a weekend-long fun project that is easy to make and uses only a few kilos of concrete. Let's begin! and let me explain the process.

STEP 1: Design Phase

at first, I was thinking about creating a 3d model first to help me visualize the object. Then I was thinking none of the cathedrals built in the medieval age was using 3d modeling technique and they were marvelous. I simplified the design to have just a long stain glass window finish as the light source with a rectangular box shape, small enough to fit in my IKEA bookcase. The design drawing is done entirely in AutoCAD. with a few simple line offset. the arch is an equilateral arch of the shape that is commonly used in gothic architecture.

the White lights are concrete contour, the yellow one is the center light source that will be made of acrylic sheet and paper

Overall Dimension 275mm x 90mm x 75mm(Depth)

I printed a few copies on card stock and ready for cutting the EVA foam sheet

STEP 2: Making the EVA Negative Shape

Once I cut all the layers of the contour line into individual pieces I can then trace the shape onto EVA foam and cut them to the exact same size, there are 10 pieces in total each with a 2mm offset. the center cavity is around 40mm wide.

The first Layer I sandwiched 3 layers of the EVA foam together to give it an 8mm+/- depth then the rest is only one sheet thick about 3mm. To make the cavity for the LED light strip, I stuck a piece of styrofoam about 30mm thick. wrapped with masking tape so it will be easier to take out after pouring the concrete.

I used rubber cement to glue the EVA foam. DO NOT use rubber cement to glue polystyrene foam , it will melt it and give off nasty fumes. use double side tape

STEP 3: Making Formwork and Pour Concrete!

Once the EVA foam is all glued together I glued a piece of PVA sheet, scrap from old file sleeve. cut exactly to the size of the box so the concrete will be much easier to release from the bottom.

Stick a piece of tube for the wire to pass.

I found a few pieces of scrap in the garage and used hot glue to glue them together. Once the concrete is poured moisture will be drawn into the wood and when concrete is set it will be very easy to remove the glue and the wood board. the wood can be cleaned and dried and use again.

Quickly made a mixing palette. Mixed the concrete as instruction and poured in the mold. I covered roughly 15mm on top of the foam form.

shake it thoroughly to get rid of the air bubble and smooth the top, and wait until it is cured.

STEP 4: Curing Concrete

After a few hours. the Top will be hard to touch I removed the 4 sides and the tube, at this stage the concrete is still workable with a palette knife if there is any big hole or unevenness now is the time to fix.

The next day I bake the concrete in the sun for a few more hours. the color is evenly tightened.

now is the time to remove the foam!

STEP 5: Remove Foam

peel the PVC Sheet to take out the EVA foam. it was very easy to remove. no mess or break. take out the polystyrene foam was quite easy as well. the masking take helped release the foam and kept it as a whole without breaking.

bake the inside under the sun for a few hours. till the color of the concrete is light, remove any sharp edge with sandpaper.

STEP 6: Make Light Panel

I print out the template on a piece of cardstock then using a spray adhesive glued 4 pieces of cardstock together to make it thick.

Cut out the panel frame and glue them together. I spray painted the whole thing with hammer finish paint to give it an antique finish.

I used an orange hue transparent acrylic sheet for the light panel. the LED light I am using is 5600k color temperature the orange will make the light a warm glow. cut it using a bandsaw, to make it more of a frosted finish. I stick a piece of translucent tracing paper on top. the paper diffuses the light more, make it softer, and comfortable to look at.

STEP 7: Install the LED Strip and Light Panel Fixture

Make sure the acrylic sheet fits tightly into the recess of the concrete form. stick the LED strip onto a piece of paper and glue it on to the concrete. to reflect more of the light. I lined the inside with aluminum foil as a light reflector. stick a piece of soft material on the bottom of the concrete for surface protection.

At last, Press the light panel into the recess of the concrete. it should be fit in place without using any adhesive.

STEP 8: Complete!

Turn on the LED and it is done! good for any indoor space. on a bookshelf as a book stopper or in a hallway corner as a night light. great for a desktop accent light as well.

Enjoy!

Comments

[annrrr]

I was fully expecting this to involve 3d printing. Excited to see it’s just some skilled cutting work to make the mold. (3d printed mold would also be cool but great to see this limited-tool project!) Inspires so many ideas!

[50crows]

How heavy does this end up being? It's really beautiful but I'm wondering if it would be too heavy for some surfaces I'd want to put it on...

[yueshi]

I think at most 2 kg. The inside cavity is hollow, the concrete is poured in minimal amount

[50crows]

Got it. Thank you! I look forward to trying to make this!

[Reidar_Vik]

Beautiful project. I liked how you got this soft light. If you have access to a 3d-printer the window frame could be made by one?? Anyone who har tried that?

[ShamWerks]

That is a brilliant idea, it's gorgeous. Thank you for sharing!

[rnjenny]

Absolutely beautiful

[yueshi]

Thank you ☺️

[FloweringPlants]

This is amazing! Right now printing the template to make my own little lamp! And I was thinking that it would be really cool to use either color resin or Glass paint to paint some illustrations on the window, in a stained glass way. Thank you so much for sharing this!

[yueshi]

Yeh, great idea. a colored panel will be stunning.

[dubreg]

Great concept and excellent instructions. I'd love to make an outdoor version with solar powered light.

[yueshi]

Great idea! Let me know if you make one.

[Ham-made]

Beautiful design and execution!
Cheers!
Mr. Ham

[yueshi]

Thank you Mr. Ham

[mercynurse]

This is beautiful. Thank you for sharing. I loved all of the pictures. I almost feel like I could follow along and make one myself.

[yueshi]

Yeh try make one, it is a quite easy material to work with.

[joechump]

This looks great! It should probably be noted though that to create high strength concrete, you actually want it to dry out as slowly as possible as the chemical reaction that hardens it needs water and time. Often this can achieved by covering with cling film or plastic sheeting. I’ve made the mistake of trying to dry it quickly with the sun and it can result in weak and crumbling concrete. Also mixing the right amount of water is key (I’ve made stuff with way too much water before but liquid concrete mix is also weak.) Looks like this turned out great though. Nice job!

[yueshi]

Thank you for your comment very helpful. I didn't go into much research about the concrete material I was using. I think there was definitely room for improvement. I still have a bag of the concrete leftover will make something with your advice in mind :)

[lgmmoretto]

This is so pretty to look at. Congrats for the build. Loved it!

[yueshi]

Thank you