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Transparent concrete!

OK, maybe not properly transparent, but an inclusion of fibre-optics makes it light transmitting. It's a German product, and, from their website: LUCCON translucent concrete is manufactured in large volume top layer concrete blocks with embedded webbed fiber optic cables, making the stone appear comparably massive as well as transparent. By cutting the blocks elements of variable size and thickness are obtained. Upon request LUCCON is available in special colors, dimensions or surface treatments, just ask us! . I'd love to see what our members could make with this stuff, or see them replicate the idea with their own techniques. Concrete lampshades?  Concrete windows?  Transparent concrete canoes? Video from YouTube will not embed. Luccon website via NOTCOT

Topic by Kiteman    |  last reply


"concrete smell"

Some 20 years ago, I built an addition onto my house. It is built on a concrete slab with 42 inch block foundation. I have a completely finished room in which I have installed ceramic tile flooring. Under the ceramic tile I used Ardex to level the concrete before tiling.  For the last 20 years I have never noticed what now appears to be a "wet mortar joint" smell. I have become increasing alarmed about the slab leaching moisture into the room. There is no visible sign of moisture. The tile is not exceptionally cold; it's just that smell.  Can anyone put my mind at rest, or suggest to me what this might be and how to remedy it. I definitely can not destroy the floor. Please advise. Thank you.

Topic by moea    |  last reply


Recipe for lightweight concrete? Answered

I am looking for a recipe for concrete that is light weight and fine enough to be cast into detail, i.e. no bubble or big gaps.

Question by hardlec    |  last reply


Concrete and styrofoam object

Just had this idea and would like to hear from someone with experience with concrete. Can I make an object - a concrete shape ( box) which which has inside full of styrofoam? I am thinking about the posibility to make staircase from concrete with styrofoam inside - the role of styrofoam is to make the the box lightweight.

Topic by sasham    |  last reply


Will concrete stick to PVC?

I'm thinking about making a concrete tube, and I was wondering if I used two different diameter pvc pipes as the mold if I could remove the concrete without damaging it too badly.

Question by PathogenLabs    |  last reply


Concrete stepping stones

I have made some concrete stepping stones (for decorative use in flower beds mainly) and have painted them to give them a detailed look. I used exterior paint,  Now I'm wondering what I should use to seal them to protect the paint from chipping and fading?

Topic by Gdlucas    |  last reply


fiber reinforced concrete $$$

Online i can see that a 60 lb bag from quickcrete is about $5. ok. easy.   Shipping----$20 to----$50----- ouch. so .   where to find it?      gotta be someplace that has 1000s of lbs of it on the shelf, and sells it at 5 or 10 bucks.

Topic by Toga_Dan    |  last reply


Raise Sunken Concrete?

Hello. I have a 5x5 concrete porch that has sunk 6-8 inches. The porch consists of a top surface with an 18 inch skirt, and a step. I believe it was a single pour.  The porch itself is in good condition, so I am seeking methods of raising it. I have looked into slabjacking, and pressure-fill lifting, but was actually looking for a pneumatic solution. any thoughts, comments, anecdotes, would be greatly appreciated. Thanks

Question by sgunkler    |  last reply


Concrete Flash Drives

These flash drives by Shu-Chun Hsiao are serious. The drives are encased in concrete and are embossed with the weight of each one, a number that correlates with the flash drive's capacity. I love the idea, but 256g sticking out the front of my desktop is just going to destroy itself. P.S. This would make a great entry for the upcoming USB Contest Concrete Memory, Get Totally Cemented via TechEBlog

Topic by fungus amungus    |  last reply


Invisible concrete cube

This concrete cube made by Daniel Franke and Markus Kison has the amazing ability to turn invisible. Thanks to eye-tracking and a video projector for each face of the cube, the cube has the view behind it projected onto its faces. The result is like looking through a glowing window instead of a cube. You can see the effect in the video. It's not entirely smooth yet, but a very cool idea. Augmented Reality Renders Concrete Block Invisible Related: Death Becomes Her Halloween Costume photo: Durchsehen, Exp. 01 (augmented perspective) by Markus Kison, on Flickr

Topic by fungus amungus    |  last reply


Concreting a shed base

I’m planning to concrete a slab for a shed with approximate dimensions of 12m x7m. Just wondering if 150mm thick base would be suitable for driving vehicles on and possibly heavier equipmen on such as a tractor. Also with a slab that size will I need to cut expansion joints in and if so how far apart. Thankyou in advance

Question by Aglife4930  


alternatives to concrete? for project similar to DIY Light transmitting concrete

Hi I recently came across this instructable   Search for " DIY light transmitting concrete" and I was wondering how I could make something similar but in the shape of a ball, or a light bulb, So I can have a LED inside it and have it shine and spin freely.  Perhaps filling a tennis ball and drilling holes for light?  Im ind of stumped on this one. any ideas???

Topic by scotteyre    |  last reply


Best way to cast concrete? Answered

I need to know how many ways there are to cast concrete. I heard of silicone used in concrete casting but I would like to know if there are other ways. Thank you very much for your help.

Question by blkhawk    |  last reply


Tool for vibrating concrete? (DIY?)

So I've been thinking of making some homemade concrete stuff with different molds I plan on making. Since I'm not a big expert on concrete and such I've been reading all over the Internet for how-to guides and what not. And something that seems to be a really good idea is to use a tool to vibrate out the bubbles and air pockets from the molds before they set... and so far I've not found any instructable here on how to make such a tool ( because it's a bit expensive to buy one, and hey.. why not make it myself) So my question is simply if any one know of a good idea of such a tool, how to make one or whatever.. (maybe modifying something, making one from an electric motor?) I need ideas!  

Topic by Mr_And3rsson    |  last reply


How to clean a concrete hearth?

We're moving into a place with a non-functional fireplace and a stained hearth. I haven't touched it yet and have no idea what the stains are.  A guess for the circular ones is wine or some other dark drink.  Any ideas for a relatively non-toxic clean up? It turns out a lot of it is wax.

Question by mole1    |  last reply


Will concrete conduct heat well? Answered

See the picture for  more detail, but I basically need to know if this design of rock-steel-concrete-pipe will transfer heat to the oil in the pipe well. Thanks in advance, I don't need big fancy explanations, I just need to know if this will be a substantial heat source.

Question by jj.inc    |  last reply


Help! My concrete is cracking!

I constructed 4" triangular molds out of cardboard (I am making coasters).I poured quikrete mortar mix into a cup, mixed with some water and poured into the molds until the depth was roughly .5".About 1 hour into drying I realized that huge cracks were forming!How do I eliminate or reduce cracking?

Question by TaylorC86    |  last reply


Concrete/Tile over laminate?

I have a plain black laminate countertop in my bathroom that shows just about every drop of water with a nice white ring.  I was hoping to do a concrete or tile top but I'd like to keep it cheap by just doing it on top of the existing laminate.  Anyone know if this is possible? Thanks!

Topic by vgavrich    |  last reply


For All the Concrete Enthusiasts at Instructables

Dr Purnell is actively seeking other researchers, engineers, scientists, designers or even sculptors and artists who also have ideas for new uses for cement.I'm not sure if anyone is interested or if someone in the community previously posted this, but I thought I might throw this out to the ingenious and innovative Instructables community. I thought some of you all might be interested.Main Page / Network Link:http://www.engineering.leeds.ac.uk/resilience/research/NACNetCementingtheFuture.shtmlLeeds engineers developing bullet proof vests from cementhttp://www.leeds.ac.uk/media/press_releases/current09/bullet.htmMight be a good way for interested Instructables folk to continue contributing on a global scale and to showcase the open-source power of the Instructables community. Plus, it might help you out if you're younger and/or looking for undergrad or graduate level resume boosting aspects for design and/or engineering programs.

Topic by MolecularMaestro    |  last reply



Concrete cooling spot for dogs

A few years back I found a website that discussed using a concrete lined depression in the ground as a cooling spot for dogs. For the life of me, I cannot find it again. What would be the best method of doing this myself? Thank you

Question by JenniferM495    |  last reply


What can I do with broken concrete, concrete in small slabs?

I have a lot of concrete from an old driveway that I got rid of with a sledgehammer. I dont have a truck to dispose of the concrete somewhere. So need to do something with it around my house.

Question by DELETED_nuwave    |  last reply


3d Printed Concrete Forms for Architectural Post Tensioned Concrete Sculptures

I am looking at the feasibility of 3D printing concrete forms to make a staircase that goes up a 4' retaining wall. The forms would be cylindrical, split in half, and during the pour would be supported using a wood support system. Ideally I would have one main highly curved support "column" (think more of a snake or spaghetti noodle) with then stairs that slide in via a mortise and tenon type connection. The stairs would be poured individually in a separate production process than the main support. I plan on using a combination of a wire mesh, rebar and tension cables for the concrete reinforcement. The tension cables would run the length of the main support beam and would be hydraulically tensioned just before the formwork was removed. I have ample concrete experience as a civil engineer and a construction manager but this idea seems like I need some outside input.Does anyone have any experience 3d printing concrete forms. What is the best material that will hold up to the moisture and high alkalinity of concrete?At this point I have no real conceptual drawings but I'm looking to see if any similar projects have been attempted and hopefully learn and improve on them!

Topic by cjh83  


will concrete cure when in a sealed container? Answered

If the container is completely full of concrete, or possibly has a small air space?

Question by theRIAA    |  last reply


type of cement for building concrete benches?

I recently bought a bench mold so I could build a cement garden bench   The mold has some delicate designs in it.   I tried using quikrite 5000 and other cements with basic aggregates already premixed, but it did not come out crisp. The designs were pitted by aggregates I think.   I am wondering if a simple Portland cement with only sand would work? I also incorporate rebar as well?

Question by JamesP250    |  last reply


Can I sharpen a machete with concrete? Answered

Hi, so I bought a machete in Costa Rica, but it's not very sharp at all. I want to be able to cut open a coconut with it, so I need it to be relatively sharp. I found a video of a guy sharpening his blade on a regular, large, flat stone using only water. I can't find a large flat stone to sharpen it with, but I happen to have a large, flat, concrete surface, conveniently located in my basement (it's the floor). Using water, can I sharpen my machete on the concrete surface, much like the guy in the video did on the rock? He pretty much just moved it in a circular pattern, at an angle to the rock. I don't want to invest any money on this, so please let me know if this is possible.

Question by Hadokendude    |  last reply


Help with fire concrete/ forge making Answered

Firstly "Hello all", I am a long time lurker, first time poster. With that out of the way, I am gathering materials to make a small gas forge to cast some bespoke jewelry for my lady wife. I know there are lots of instructables regarding the process, but all seem to contradict each other in some way. I am going to use Fire Concrete as the lining as I got 2 tubs super cheap, and the pot says to increase temperature slowly over 4 hours and fix cracks that appear which is simple enough. Guides that use fire concrete just say "when its ready" then fire up the forge, but I dont know how to get it to the ready stage, do I need to fire it slowly over 4 hours or just cure it over night? And those that use quikrete say to bake the forge for several hours, but as I am using fire concrete do I need to do that or not? From what I have been reading around I cant do too much to mess it up, but I do need help with understanding how to cure the fire concrete Thanks

Question by Pondis    |  last reply


Remote controlled concrete trowel machine

Hello I do not know how to build this type of machine. I was hoping someone in this forum would be able to build one and share it with this community. I do not know if the machine is under a patent or not. If it is under a ptent perhaps certain aspects of it are not.The company that was building these was called Tibroc in USA. But they are no longer around. Anyway if someone can help me out and build one and share it so that I can build one that would be great.

Topic by dimatek  


Right ratio for making bowls with concrete? Answered

I recently got someone to buy me concrete mix - I asked for ready mix as I've seen people suggesting Quikrete, but I ended up with 2 bags - one with the cement and one with the gravel and sand. Now, I want to make smallish bowls for outdoor use over the weekend (bird baths, small plantholders, etc.), but I'm not sure what my ratio must be for the sand / cement or sand / cement and gravel mix (and I'm not planning on buying another product). I've read that people can mix only the sand and cement for a smooth finish, but will this be strong enough? The gravel I have is quite large, and it might make the finish too chunky when the concrete is dry. I'm also planning on not using bowls or containers as molds - I want to smooth it out on the outside or inside of a bowl by hand with a trowel or something similar. Will I be able to make this work? I want to make small bowls, so I don't need to mix large amounts at once. I have never worked with concrete before, so I want to start out with small items anyway just to get the hang of things.

Question by Nocturmia    |  last reply


Concrete propane grill - Heat issues?

I'll be making a concrete counter top for my outdoor kitchen. I'll shape a "box" in the concrete (just like a concrete sink), and build the propane burners into that. Will I run into any heat issues with the concrete? Should I line it with something to shield it from heat?

Topic by DenMike99    |  last reply


2 part resins incompatible with concrete???

While researching patch kits for pebble and resin coating for concrete stairs, one supplier claimed that ONLY their resin would not eat concrete.   Is it true that some resins will eat the concrete? Will fiberglass resin work for this? The pebbles are about 1/8"

Topic by Toga_Dan    |  last reply


how to make liquid antifreeze concrete?

I need that how make liquid antifreeze concrete & a new formulation for product,thanks my friends

Question by anoosh khan    |  last reply


Building small objects out of concrete

Hi all, I was wondering if i could get any pointers on mixing concrete, I have gone through the concrete mixing instructables already and have not found anything suitable and hence I am asking her. I want to formulate an open recipe to make concrete objects like the ones in the following links, http://fancycrave.com/concrete-desk-accessories/ http://www.ledindon.com/en/objets-design/9029-stylo-plume-beton-arme.php http://www.designboom.com/design/concrete-rollerball-pen-by-22-design-studio-at-designboom-shop/ They are mostly small objects where the wall thicknesses are quite small (maybe a few mm). I think it will be interesting to see a DIY approach to making a concrete composition that is strong in small thicknesses, i think a lot of cool objects can be made from it . I have tried the normal concrete mix with cement and sand but i am not able to get it strong enough at those small thicknesses. Can anyone please some suggestions or advice on how to go about this ?  Thanks in advance, please see attached files for some images taken from around the web, i do not own any of them.

Topic by varun2021    |  last reply


August Build Night with Cheng Concrete

Since the moment that truck pulled up with the pallet of Cheng Concrete on it, we've been having a ball with our Shapecrete! We know the August Build session has ended, and Eureka Factory members managed some fun build projects before the month was over, but we've still got Shapecrete and we're still creating with it!  It's really interesting stuff, obviously a natural for Halloween decos (saw someone else had made some cool headstones!) and yard art.  Love how adaptable it is and the ability to easily create small concrete objects with it.  We've got a few more projects underway and will continue adding them to our Shapecrete Collection as long as there's Shapecrete in our buckets!  Thanks, Instructables, for a really awesome build opportunity, and thanks Cheng Concrete, for a truly wonderful medium!  If anyone is in Orlando September 12 & 13, be sure to stop by the Eureka Factory  booth at Maker Faire Orlando, on the 2nd floor lobby of the Orlando Science Center, where the event is held,  to see Gnombie and some  of our Instructables projects!

Topic by EurekaFactory  


Murphy Bed Challenge - concrete wall?

I am moving into a former jeweler's office loft. Awesome! Not so awesome:  everything was built for MAX security. This means these jewelers installed concrete on walls around their safes.  This includes my new "bedroom" which is on the other side of a 10 foot safe. I am attaching a pic with some notes on it to show you the challenge I am having. Since I wanted to  use a murphy bed, I found this tutorial here: https://www.instructables.com/id/A-Murphy-Bed-Installed-Sideways/ However, I do not have a murphy bed frame with which to do this. My bed weighs about 100-ish lbs and is a queen sized memory foam bed. For the masonry/concrete issue, I am considering mounting the murphy bed to the floor, as shown in the aforementioned tutorial. Here are my concerns:  1) How do I drill into concrete and masonry? What tools are best for this job? 2) Since I don't have a murphy bed frame, how do I properly build one? 3) Can I get shocks or springs going on this thing to make it easier to fold into the wall? 4) How can I get the folding-action just right? This room is SMALL, it only really is going to fit my bed.

Topic by gigijiji    |  last reply


Heated concrete garden seats question?

Next year I want to use the garden a lot more, so this winder I'm building a gas bottle wood burner like btop & maybe a BBQ like Babe-BQ from abitdifferent (have access to a few bottles of various sizes) and some concrete (maybe papercrete, if i can gather enough old paper for the whole job) bucket style seats, as I have lots of left over cement from a previous project where the inlaws over estimate (by a large amount!) So i can use it longer through the year, I'd like to have them heated with some pipes going through them being heated off the burner. I'd have a copper coil at the burner end, but ideally to keep costs down, i'd like to use PEX in the seats.  Will this transfer enough (if any) heat outside the pipe? and also will the concrete absorb the heat?  I was thinking of placing the pipe 10/15mm deep and having it coil back and forth from front of the seat  by the knees to the back by the shoulders and back again, 2 or 3 times per seat. It will be a modular design, for smaller molds and adjustability, with each seat connected to the last. I've added a quick drawing i made. Hope it makes sense. Was also thinking that I could also set up a solar heater as a pre heater to heat them in the to just take the chill off, but thats a different project for another time Any suggestions or advice greatly appreciated. Tuns 

Question by tuns    |  last reply



Can decomposed granite be mixed with cement for use as structural concrete?

We have a mountainous property with no sand and very little rock other than granite. Can I use decomposed granite (as fine as sand and small pebbles) as aggregate, instead of river gravel and or sand?

Question by MikeT107    |  last reply


IDEAS TO UPDATE A CONCRETE FLOOR IN AN ARIZONA ROOM.

Ideas for personalizing an indoor concrete floor

Topic by cinderellato    |  last reply


How do I level a concrete floor?

I removed a wall down the middle of my basement.  It had a concrete footing which came out with the curb when it was removed, but the concrete floor on one side of this area is one inch higher than one the other side.  How do I level this so I can install a floating laminate flooring?

Question by Shirley Harrison    |  last reply



Has anyone tried to stain concrete with shoe polish, hair dye, or other household substances? Answered

I am casting small concrete panels for Xmas presents. I like the look of stain more than integral color, and am wondering if there are options to stain the pieces outside of commercial acid stains. The pieces will be decorative only, and not need to stand up to wear and tear like floors, countertops, or even coasters would. Would like to hear about unsuccessful attempts as well. Thanks!

Question by Owlman76    |  last reply



How do I pour a concrete slab between other slabs and add an anchor to the new slab?

I have a space out the front of my house that I want to turn into a chain anchoring spot for my husband's scooter. I've included a photo of the spot for reference's sake (I really need to clean it out and excavate >.<) Most of the area is already concreted in but there's a space about six feet by three feet under the kitchen window that I want to fill in. I watched a few videos on how to do it and the information given was great but it showed how to pour new slabs in areas that aren't already concreted so now I turn to you guys. I also, as part of the slab, want to install a heavy duty anchoring point for the scooter that can't easily be pulled from the ground and will take a heavy duty steel chain through it. Any advice?

Question by PaigeGrel    |  last reply


WILL CONCRETE STICK TO CAST IRON OR ENAMEL as in bathtub

Hi everyone.  This is my very first Instructables experience - I've just found you guys.  I'm wanting to know if I could resurface my old cast iron enamel bath with concrete??  Would it stick???

Topic by CraftyCarolyn    |  last reply


how do i make a column with concrete?

Molds, iron/wire gauge, how deep I must sink them in the dirt (semi-soft soil) and how it is supposed to be the foundation. Also the "specifications" for the concrete like which and how much sand and gravel to use with the cement note: they must have out side the ground 3 to 3,5 meters in height, that is about 10 to 12 feet in height

Question by lidiarichiniti    |  last reply


how much concrete do i need? Answered

Ok folks im building a bushfire bunker and i need to know how much concrete i need to make 4 walls 10cm thick 2m high and 4m long what kind of concrete i need and what kind of mix it should be how i should mix it etc i have had almost no prior experiance concreting so any tips would be appreciated

Question by milamber    |  last reply


Raised Garden Beds out of Concrete Blocks?

I want to build raised garden beds with the walls being made out of concrete cinder blocks. Want the beds to be about 2 1/2' above ground and about 3' to 4' wide. I also want to make basically concrete counter tops to put on top (or benches). My question is .. how many inches can the top go beyond the concrete cinder block frame without having to add braces for the bench? Ex: if I use 6" wide cinder blocks .. and fill the holes with rebar and concrete .. what is the overhang I can have on the bench top?

Question by RayVyn    |  last reply


Building a fence

I am going to construct a fence between my garage and my house. 20 ft or so long, To keep my too small dogs contained. Here in lies the rub, I have already built one fence. it's still up and working fine, however in the construction I discovered how dense the crete is, ramset doesn't work, drilling? I would never get deep enough. So I have decided to use cement piers and 4x4 posts and sit the fence right on the concrete, with enough weight I am praying the fence will not move much, I only need to contain two 5# dogs its mostly ornamental. If anyone has attempted anything along these lines, please contact me with your triumphs and failures, or any advice you may have thanks!

Topic by colurblinde    |  last reply


August 2015 Build Night with Cheng Concrete

#BUILDNIGHT **You must be located in the United States to enter this event** 30 SPACES AVAILABLE Deadline to sign up: Friday, June 19th. Accepted spaces will be notified by Monday, June 22nd. Read our FAQ to learn more about the Build Night program rules and how to make the most out of this event for your space. AUGUST BUILD NIGHT We are partnering with Cheng Concrete for our August 2015 build night. Sign up to participate in the build night and we will ship you a package that includes the following: (10) 20lb Buckets of Shapecrete HOW TO PARTICIPATE: Host a Build Night: pick a time in August to host a project build night using the Cheng Concrete Shapecrete. You can host multiple build nights during August to work on your projects. Post 2 Instructables: post 2 Instructables using the Shapecrete. Not posting these Instructables will affect your chances to participate in future build nights. Brownie Points (not required): after the build night post a forum topic on Instructables about your event. Include pictures, stories, etc... Here are two examples from past build nights: Noisebridge and Makers Local 256. We may even feature your photos on the homepage. REWARDS: If your submitted Instructable for this event gets featured by one of our editors we will send you an Instructables Prize Pack which includes: Instructables t-shirt, stickers, and patches. This forum post has guidelines for posting feature worthy projects. Be sure to let people at your event know so they can win a prize pack! Limit 3 per makerspace. RESOURCES: Cheng How-To Center Shapecrete Instructables App (for documentation during the build night): iOS and Android REACH OUT TO US ON SOCIAL MEDIA #BUILDNIGHT #INSTRUCTABLES #Shapecrete Twitter: @Instructables, @CHENGConcrete Instagram: @Instructables www.facebook.com/chengconcrete https://www.facebook.com/instructables SIGN UP: Fill out this form **You must be located in the United States to enter this event**

Topic by Carleyy    |  last reply