Step 5: the big pour

Mix up enough rockite. I'll leave this up to you to figure out. Pour it slowly into the mold, until it comes flush with the top edge. you can overfill it a bit and then scrape it flush after about 10 minutes. Invert the base over it to cast in the legs (you can glue these temporarily into the base with a glue gun, or use duct tape or something. You don't want to lose them to the concrete abyss.

Once it all looks good. put it away for at least 12 hours.

<p>Wow...Its amazing!!!!</p>
What an informative post! I have been looking for <a href="http://www.leesurepools.com/pool-remodeling" rel="nofollow">decorative concrete in albuquerque</a> for a pool, but I had no idea you could make a lamp. This is going on my things to do list!
I love this idea! i definitely want to try it! Where did you by the concrete? There is a lot of <a href="http://www.oldworlddecorativeconcrete.com" rel="nofollow">decorative concrete in katy tx</a> so I need to make something to blend in with the rest of the city! Thank you for providing the instructions.
Looks great and very clever! Just to prove I have no life, I'll throw in the following: It's cement when it's in the bag, and also when it's in a liquid (or semi-liquid) state. It's only concrete after it's hardened. "Hardened" because cement does not "dry" by evaporating water. It hardens--into concrete--by a chemical reaction. OK, sorry to be such a stickler, back to the lamp. Lamp's cool!
Umm...not to be a jerk, but, that's not what I have been told. I was told that it's cement when it's dry, concrete when it's mixed with the other ingredients that make it concrete, and... My stepfather was a General Contractor, and I have other family that is in construction also... they've always said that you have to wait for concrete to "dry" and that is why it isn't good to lay concrete in wet or cold conditions. Hmm...
It is true that the concrete &quot;cures&quot; and doesn't just dry out. Also are you sure you heard them correctly? In northern Australia (where I am from), it is often too hot for the concrete to set evenly (causing cracks etc.). To combat this, most &quot;pours&quot; are done late in the afternoon when it is cooler, and then once the concrete has begun to set, its given a good spray with the garden hose. I honestly think (though i'm&nbsp;no expert) that being wet&nbsp;and cold are ideal conditions for curing concrete.<br /> Oh and i'm not sure but I remember seeing a documentary on the&nbsp;construction of a huge dam somewhere&nbsp;(maybe&nbsp;in the U.S. or China? pfft) where they actually had to chill the concrete to prevent it&nbsp;from curing too rapidly.&nbsp;<br /> And I think they actually&nbsp;added ice to the mix when&nbsp;building the Burj Dubai. But that was to stop the mix from seizing under the pressure&nbsp;when being pumped up so high...
well, if the concrete dried to quickly, wouldn't it crack? like mud?
It can but is more likey to spall.<br>Thats when concrete freezes, or cures too hot, and after curing the top smooth surfaces slake off in chunks, exposing the rough rocky interior, making surface look like broken concrete.<br>Canoeman<br>
interesting.... might be a design element to take use of. that is if the concrete wouldnt just fall apart or something.
Its the hooover dam.
If it's really cold it can be important to keep the pour warm while it cures, because clearly there would be trouble if the water in the mix was to freeze.<br><br>Large pours have to be watered, often for several days after being laid, because the curing reaction is exothermic. Setting concrete actually produces some heat, so a large amount of concrete setting can cause enough heat to be problematic.<br><br>I've never bothered with the semantics of concrete vs cement, and I figure nobody will be confused by using set, cure, and dry interchangeably.
I am a division of the state architects structural inspector, and was a general/electrical contractor for 30 years. Cement is a dry powdery ingredient, in concrete When it is mixed with sand, and aggregate (rock) it becomes concrete mix. When you add water, it becomes concrete Cement is made by heating limestone (calcium carbonate) with small quantities of other materials (such as clay) to 1450&nbsp;&deg;C in a kiln, in a process known as calcination, whereby a molecule of carbon dioxide is liberated from the calcium carbonate to form calcium oxide, or quicklime, which is then blended with the other materials that have been included in the mix. The resulting hard substance, called 'clinker', is then ground with a small amount of gypsum into a powder to make 'Ordinary Portland Cement', the most commonly used type of cement (often referred to as OPC). Portland cement is a basic ingredient of concrete, mortar and most non-speciality grout. The most common use for Portland cement is in the production of concrete. Concrete is a composite material consisting of aggregate (gravel and sand), cement, and water. As a construction material, concrete can be cast in almost any shape desired, and once hardened, can become a structural (load bearing) element. Portland cement may be grey or white. After pouring concrete, it is important to keep the concrete hydrated and above freezing temps. Hot weather will cause the outside of the concrete to begin curing faster then the inside, causing shrinkage cracks, As concrete cures, it produces heat as a chemical reaction. When looking for a smooth outer surface, use a vibrator to remove bubbles and consolidate the concrete. Keep it cool, and if possible cover it with plastic after the surface has cured long enough, so it will not leave plastic fold marks on the concrete. If you are making a lot of concrete objects, a fairly inexpensive cordless drill mounted vibrator that has a phallic shape can be dipped into the concrete to consolidate and remove exterior bubbles or what is referred to as rock pockets. Once you remove the forms, keep it covered for as long as you can to prevent cracking. Vibrators can be rented cheaply at tool supply centers Humidity is concretes friend, when curing. To add a nice touch, quartz, turquoise, minerals and fossils can be imbedded into the mold when pouring, then polished with a hand grinder when finished. The colors really stand out, after grinding, and coating it with a clear concrete sealer, to give that wet river rock look. Hope this info helped. Canoeman
I live in England and when I worked for a leisure company installing patios and conservatories I regularly used to have to lay concrete in the wet or cold conditions; It does set, but it just takes longer, it sets through a reaction withthe lime in its mix.<br><br>and to help with the Concrete/ cememnt argument , the English Oxford dcitionary defines the following:<br><br>&quot; Cement/ noun/ : a powdery substance made by calcining lime and clay, mixed with water to form mortar or mixed with sand, gravel, and water to make concrete. &quot;
but the weird thing is concrete will set under water and is alot stronger because it cures more evenly
I'm not sure if you said this or not (I couldn't understand what you said exactly), but cement is an ingredient for concrete. Concrete is made up of sand, rocks, cement, etc.
Waaaay cool. I'd like to know what the weight difference is between that RockStuff and standard cement. Guess I'll find out soon enuff. Great work!!
This could also be done with concrete backer board, and then troweled with grout, to eliminate mixing concrete. Then sanding grinding the outside smooth, to expose the glass.<br>I have built a few pony walls like that.<br><br>(pony wall = A short partition wall about 3 to 4 feet high.)<br><br>Canoeman
how much does it weigh?
I wonder if you could add the same materials to the concrete/cement mix that is used in making the lightweight "concrete" planters and such? Or, would make it not as heat/fire-proof, I wonder? Although, if the light source was a lower wattage, would that matter?
broken glass added to the mix maybe. if you left glass in a cement mixer with just the sand and let it run for a while it would take the sharp edges of the glass and give sand blasted effect to the glass. i dont know if adding water would help.<br>This is kind of a new technique used on concrete floors and some wall covering <br>where nails, screws, glass, and bits of well anything really is added, then ground flat to remove sharp bits using Carborundum Stones. mosaic of bits of crap<br>http://www.youtube.com/watch?v=ogVYwPcsnqY
I once made some concrete sheres with chunks and strips of aluminum and pewter in the mix. and ground the surface, exposing the aluminum, then polishing the outside, then polishing it again with bees wax, they were beautiful.<br><br>Canoeman
Maybe to prevent alot of the light from being absorbed by the grey concrete you could paint the inside white. This would reflect alot of the light and allow more to come out the top, bottum and sides.
Conrete dye is available from any builders supply, in just about any color you can imagine.<br>It can either be mixed in, or rubbed on soft curing concrete.<br>It comes in a powder form.<br>
&nbsp;an interesting idea would be to embed&nbsp;fiber optic&nbsp;cables in the concrete, to make it slightly translucent.
Fiber optic transmission of light through concrete is a good idea that has already been done.<br><br>Without the expense of communications grade fiber optics, acrylic rods and fishing line have been used to transport light through concrete in years past.
Ok so I did all the steps but I'm still having trouble getting the light to shine though the concrete.... any suggestions? Btw if it dont let light though it makes a great hat.
lol. 15 lbs hat.....
One of the best lamps on here. Period.
Great work! I'm in the decorative concrete field; counter tops, floor overlays, furniture, vertical stamped and hand carved concrete, and on occasion a dinosaur statue :) This is a design I haven't seen. I will definitely be making one of these. Thanks Concrete Phil
concrete phil i know a concrete pete u 2 should meet up
I'm thinking of using two pieces of glass and putting a mould on the front to take speaker drivers so the front has the two edges as glass with speakers down the center that would be cool .... the sides could all so have a design in them "its a shame to have all the sides in glass under concrete and not use it" if i get round to doing this ill let u know should work though...let me know what u think... did you use any mould oil on the wood/foam.... or do you think if i used plastic over the inside of the moulds that would work cause i like the very smooth finish it produces...
am I seeing correctly that your wall is also covered in / made of concrete?
Very beautiful!
Very stylish, very modern and sophisticated. I love it.
this project reminded me of something i would have done for a class back in architecture school. then i saw the image with the graphic standards in the background and couldn't help but laugh! Thanks for the post.
Maybe not for everyone to build but yes: Slick.
That is freakn' slick! One thing I learned by casting metal, porcelain, wax and plaster: use a release agent. I find petroleum jelly works best. It's messy, but it will fill any little voids that the material will get into and cause your mold to stick. I think I'll try this one with a twist. I want to put colored glass on top of the large panes in a pattern. Sort of like a stained glass effect. Or maybe a T.A.R.D.I.S. !
To answer a few questions: It's 16" tall, 4" square. Probably weighs about 15 pounds. Walls of the shade are 1/2" thick. Yes, your formwork needs to be able to release. I used packing tape which works well on flat surfaces and leaves a smooth finish. Petroleum jelly works well but can leave marks. The glass is smooth enough so no concrete will stick to it. The design is intentionally restrained. There's a lot you could do with this technique. Please, modify and experiment. I'd be curious to see how it goes. Thanks for all the nice comments.
This is a GREAT design! I love the "Industrial" qualities, but also that it looks Modern, Sleek, and totally Fresh! I really, really do love it! I might try this, but, I might think about adding that material(s) that they add when making Planters, in order to make it more lightweight and less costly. I don't know. I've been thinking, though, of adding lamps, one of a kind and others, to my list of "products" to sell once I get my website up and running. Even if I altered this design a little, I think I'd feel that I would have to credit it's original design to YOU. How could I go about doing that? Would you have a problem with that?
Stick tinfoil on the outside of the glass (between the glass and concrete) so that a bit less light is absorbed by the inside concrete walls. This might make the overall light output a tiny bit brighter and reduce heat buildup a little.
Or, what about using Copper-Foil Tape, as is used in Stained Glass Constructions? Just a thought. It might be a little less work and a little neater. If anybody else already suggested this, sorry, I haven't read the whole thread yet, and I am new here.
That's pure genius. I love it 5.0! I'm soooo gonna do this!
Thats awesome. This would cost ALOT in a store. Remember: BE PEACEFUL BE ZEN BE SIMPLE Great job!
How heavy is the final product?
Excellent Work.
Wonderful Work! Congratulations!
Great work, good instructions and pictures. Rock on.
haha rock on lol great lamp!
A simple trick to avoid bubbles in the concrete is to hold a sanding machine against the mold. This will vibrate te mold and force all the bubles in the concrete to go up.
well done from Rick in the UK<br/><br/><h2><sup><span class="underline"><strong><sup><strong></strong></sup></strong></span></sup></h2>

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