# Forum Home Renovation Kitchens  Concrete Countertops

## HigherPlane

Hey All 
This is in response to a question in another thread unrelated to concrete countertops. I'm currently building my first kitchen. Being the first DIY project I've taken on, it's taking forever, because being me I tried to do everything myself, from designing and building the carcasses to making concrete countertops. 
I ended up going down this road after finding the cheapest quote for granite, corion, engineered stone etc I could get was $4600 (not including GST of course, god I hate it the way trades are still aloud to do that - rant over). Anyway I ordered a few books on how to make the countertops and went from there. 
I'm not going to go through the whole process of how to make these as there is plenty of info available online about that. However, if anybody has any questions about them I'd be more than happy to answer. It'll be nice to be able to give something back to the forum. 
I will say it's a pretty involved process making these things and I'm still in that process. I've taken lots of photos along the way. I've attach three to show some of the process. The first is the nearly finished mold of the sink run. The next is the how it looked straight out of the mold and with the stainless steel trivets laid in to make sure they actually fitted. The next is how it looked after it's initial grinding (to 500 grit). I'm going to polish them tomorrow (to 2000 grit) then seal with a penetrating sealer. There are six of these in total for the whole kitchen including the waterfall ends to a couple of the countertops.     
 The run I've uploaded the pictures of is the most complex of all of them with the sink and the holes for trivets and the wash in to the sink.  
 If you believe one of the recent home and garden mags (or one of those type of mags  I forget) it costs about $1750 per square meter to have these things made, before you start paying extra for sink wash ins etc (and I'm beginning to understand why). I've got about 5sqm in my kitchen so not a bad saving I think. I'd estimate conservatively it's cost me about $2500 to build these, however I've got some great tools out of that as well such as a big cement mixer.  
 I answer to your question Gaza the mix I'm using is as follows:  
 17% cement
 28% aggregate
 55% sand
 and based off the weight of the cement
 1.5 ml of plasticiser per kg of cement (use whatever the package on your stuff says though)
 2.5% (each) of the cement weight of black and blue pigments
 also add as much fibers glass fibers as the package will allow (apparently this helps to stop cracks forming (thus far it has worked).  
 These things are not light, all up I have made about 700kg of countertops. Anyway I'll post more pictures as I progress.

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## Cecile

I really, really love this look, although I'd have a much deeper sink.  Terrific-looking job  :2thumbsup:

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## jago

Congrats on what looks like a fantastic counter top...I'm feeling inspired.   what would you say was/is the biggest cost ?what do you estimate your square metre cost is ?are you very experienced DIY'er? 
Cheers Jago

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## jiggy

Very impressed ,now i just have to delete your pics before my wife sees them! Any idea what sort of weight and do you need any extra support ?

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## golfcore

I'd be very interested in pics of the finished product in situ.

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## multiblade

Hi,
There is a really expensive product that would be perfect for doing this except it is so expensive it voids the point. Its called cemlite and cemlite he.
Its about 60% the weight of concrete and at 28 days achieves cemlite 35mpa and the HE version is 42mpa. Great white product so it tints to unsullied colours, just too bloody dear.
cheers.
Not that it really matters re the colour as yours look great.
Cheers
mike

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## arms

> I really, really love this look, although I'd have a much deeper sink. Terrific-looking job

  i do believe that the poster will glue an undermount sink bowl  to the bottom of the cast

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## HigherPlane

Thanks for the compliments guys.  
 Cecile  Tom is correct this is just the top, it's sitting in the temporary grinding station in that picture. When I put it on top of the cabinets in the kitchen there will be an under-mount sink on the bottom of it.  
 Jago  The actual cost per square meter of these are very low. Most of the cost is in the setup. For some serious DIYers it might not be too much, as they would already have a lot of the equipment. For the setup the big ticket items are a cement mixer, a vibrator (stinger clamped to the table) (don't even think about using a sander to vibrate the mix as some suggest, it wouldn't even get close to good enough), a wet grinder and diamond pads. I went cheap and nasty for all these off ebay. All up they would have cost me about $1200. Other than the water feed jamming on the grinder (I just use the garden house and a shower attachment now) they seem to be going alright. There are quite a few little things that start to add up as well I guess such as bolt cutters to trim the rebar and mesh. Also for making the molds it helps to have a good array of power tools. You could get away with less being creative but I have used a table saw, slide compound miter saw, circular saw, jigsaw, router and drill to make the molds.    
 Also you need to make up temporary tables to put these on while you pour and grind them. I did this with a sheet of chipboard  with a few cheap non structural pine beams running length ways screwed in. Then flipped of and put on a few saw horses (each table cost about $100). Somebody might have a better idea for that. They need to be able to take the weight of a mold though and handle the vibration of the stinger.  
 Once you have all this stuff really it's only the cost of the melamine for the mold (use $30 sheets from Bunnings), a few things like screws, masking tape and silicon caulk. The re-enforcement (rebar and mesh) cost $200 including delivery and I have a lot of mesh left over. For the fiddly bits like sink voids I spent $30 at Clark Rubber for some foam. The actual mix is cheap:
 Gray 20kg bagged concrete
 Sand and aggregate $50 all up for 250kg of agg and 500kg of sand from a landscaping place
 Plasticiser ~ $20 for a lifetimes supply
 Fibers, roughly $60 all up for the 6 tops I'm making  
 Pigment  I used blue and black. Black is cheap but blue is fairly expensive (I probably used about $150 of blue in mine all up and $50 of black.  
 In answer to if I'm an experienced DIYer...no. This kitchen is the first thing I've done other than the odd washer change in a tap and a bit of painting. I've got a lot of spare time on my hands and a lot of persistence. I've designed and build all the kitchen cabinets myself, (I just got a melamine company to cut the sheets up for me and edge the bits that needed it). I've got a $15,000 budget for the kitchen (that's for everything ie plumbing wiring appliances). A large proportion of this has gone into tools, which means I'm really nicely kitted up now.    
 Jiggy  I only added a bit of extra support for the 'island' part of the kitchen where the cabinets can't also be bolted to the wall. Through use of great engineering talent I figured I would be quite happy to stand on the cabinets myself (even jump up and down a bit) and they would be fine. My weight being roughly equivalent to the weight of concrete on a cabinet. I'll post some pictures of the carcasses at some stage.  
 Multiblade  Yeah, I've seen some interesting cement type products available. If you were going to go into business doing this they'd be well worth looking into, as some of them you could tout as being 'green'.

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## tortfeaser

Looks awesome. Keep posting pics. I'm totally into this look, knowing you've pulled it off with the experience you have has definitely got me inspired.

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## tortfeaser

A question - is the finished side the bottom of the mould, or the side the concrete is poured? If the bottom of the mould is the finished side (that's how it looks in the pics), how do you deal with the blocks that are holding the reinforcement up?

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## HigherPlane

Here's a bit of progress. Sorry about the quality of the pics, they don't really do justice to the gloss of the countertops. I'll try and take some pics with a real camera at some stage and not my iphone. 
Tortfeaser - You're correct mate the bottom of the mold is the top of the countertop. As you can see in one of the pictures you just hang the reo with some wire and once you've screed the top you cut the wires. The foam is just there to help get the level right while you attach the wires.

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## shammo

looks amazing!! never seen what you have done with the sink there.
cant say i would use the plastic legs with that much weight though. 
what type of drawer runners are you using there, look like a fancy soft closing type?? 
keep the pics coming, doing an awesome job

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## HigherPlane

Yeah I've gone for the soft close draws. They are tandembox draw runners, the brand is Lobek. I'm not really sure how it all works but these I think are at the lower end of the range. I think Blum stuff is pretty much the same mechanics but they use really nice stainless steel finishes etc. I might be wong about all that though, maybe somebody more in the know could explain it. 
Each leg is rate to over 100kg so no issues with a few taking the weight. I made all the cabinets myself and being a bit unsure about how many screws to use I went for the overkill, so the structure is really strong.

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## tortfeaser

Thanks for the update. I see a bevel on the very end of the stove bench, in pic 2. Are you planning another concrete slab on the end of the cabinet to the floor? How hard was it to get the concrete in to the _\ angle of the bevel?

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## HigherPlane

Hey Tortfeaser 
Yeah it is a 45 degree bevel so that it will be a nice miter join for the 'waterfall end' piece. This is the only part where I have really gone out on a limb. I couldn't find any info online about doing this, so I'm really hoping there isn't a really good reason the pros don't do this! 
In principle though it is the same as the granite/fake stone guys doing the same thing. However instead of cutting the 45 bevel in I made it part of the mold. It's not a particularly tricky thing to do with a table saw and probably dead easy if you are not as incompetent as me with a table saw. You are basically just putting another piece of melamine into the mould with 45 degree cuts on both lengths. It's fiddly work getting the caulk into that 45 degree corner though. I'm anticipating having to a bit of sanding with the diamond hand pads once I joing the pieces up to get a nice finish. I'm really hoping this isn't going to be an epic fail. 
I could have gone down the road of making the mold too long and then cutting it with a concrete cutter. The only cheap option I could find was some ryboi wet cutter at bunnings, but it couldn't cut the depth required to go through 60mm of concrete on a 45 degree angle. If anybody has any suggestions on this I'd like to hear them. As it would probably be and easier method and potentially more accurate. 
I'm a bit of a perfectionist and I really don't like the look of butt joints with any sort of stone. Anyway I should be outside cutting up the side pieces for the next lot molds.

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## tortfeaser

It'll look great. The corner you have looks good. I hadn't thought about the caulk problem, but did think getting all the voids out might be a challenge. 
Thanks for sharing.

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## Tim M

HI Higherplane, just wondering if you could tell me a bit more about your plasticiser. I am in South Australia, and am having a lot of issues in finding some without buying 200lts of it. If you could let me know: 
Which brand you used?
How it worked?
Where u got it?
Approx price etc? 
Thanking you in advance. 
Cheers, 
Tim

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## dykapal

:Brava: you are definitely a maniac))))  :Yikes2:

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## HigherPlane

Hey Tim 
Just got it at Bunnings mate. It's in the section with the concrete sealers etc. It's brick layers plasticiser. It wasn't much, I think about $30 for a life times supply. You use bugger all of the stuff, compared to the amount of concrete. I'm actually dubious as to if it's doing anything. You're talking a few mls of the stuff compared to 90kg of concrete. However, I wouldn't risk not using it, just incase.... 
If anybody is planning on doing this get Chengs book on it or Buddy Rhodes. There are so many little things that you just wouldn't think of. There's definatley some gaps in the books and I'm happy to give my limited advice on what's missing and how I got around problems. 
Your problem of sourcing stuff Tim has been one of my biggest problems in this project (the whole kitchen not just the countertop). Stuff like finding a steel fabricator that was interested in polishing six poxy little square bars up for my trivets to finding where to get the epxoy to glue them in with. 
If you have any issues sourcing stuff or think what you're paying is too much for something I'm happy to share where I got things. I've really tried to do this on the cheap. Generally I buy good quality tools but I wasn't sure how this whole project would go so I didn't want to go out and buy expensive wet grinders and stingers etc

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## Tim M

Thanks HigherPlane, much appreciated.  I have Chengs book and find it reasonable comprehensive.  Should have asked you last time, what ratio did you use the nylon fibres in relation to concrete mix? 
Cheers, 
Tim

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## murray44

That is a mega impressive piece of work.  :2thumbsup:

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## HigherPlane

Thanks Guys 
Tim - I use 0.0006% of the weight of the cement for the fibers ie. 100kg of countertop needs 60 grams of fibers. I think I halved the maximum amount suggested by the packaging as my test piece looked like an albino gorilla. You find though that polishing removes any evidence of the fibers and if you can't remove them on the bits you are hand polishing, just take a lighter to them and they singe away like your arm hair would.  
Cheers  
Matt

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## seriph1

Brilliant job mate .... awesome!  
Cheng's DVD is great too

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## Tim M

Thanks again Matt, Will let you know how I go. 
Cheers, 
Tim

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## andie99

Looking good, I would want to have such countertop, we are just renting our house and still planning to buy one. They use tiles and I kinda brush them so often  :Frown:

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## seriph1

Thanks for nudging this thread ... I just watched Cheng's How To video again last week and enjoyed it again ... I am thinking seriously of doing this for our kitchen and have been wondering if ultra fine aggregate would be OK to use as I would rather it than the coarser stuff. I am also wondering if high gloss laminate (over MDF) would help create a highly shiny finish, requiring far less polishing .... might have to test it out as a small project to work it out.

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## WillyInBris

Why oh why did I open this thread  :No: . 
I will say that is just fantastic my wife saw something like this some time ago at a show I think but they wanted mega bucks so she never told me the price. 
With a new kitchen coming this year in the next house I may have to give this a go as I wasn't impressed with the laminate benchtops in the last house we renovated they were ok but costed as much as it looks like your tooling did for this project.   :2thumbsup:  :2thumbsup:  :2thumbsup:  
Can anyone send me links Chengshow to video. 
Thanks Willy

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## jago

Higherplane how goes the kitchen Reno any updated pictures?

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## HigherPlane

Hey Guys 
Sorry this took me so long, I completely forgot about putting up the photos. Here's the finished product. 
Cheers

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## stevoh741

thats awesome mate. Are they stainless bars in the dish drainer? Would you do it that way again or leave it as groves running right to the sink opening?
cheers

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## djsherly

Thanks so much for the update. Can I ask where you sourced the fibres from? Fantastic work by the way!

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## Godzilla73

G'day' 
Looks great, how thick are they about 70mm? Could you go less? What did you use to bond the mitre on the slab ends?

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## HigherPlane

Hey Stevoh, Thanks mate. Yeah that's 317 (marine grade so no rusting) stainless steel square bar. I would do the stainless steel again as I really like the look. You made me think though, it might look good to run the stainless steel bars all the way to the sink. You could definately do the groves if you wanted and shape them however you wanted as well. I like the square bar though because I've found we don't need a dish drainer. We put most of the washing in the dishwasher (it's fully integrated that's why you can't see it in the pictures) so there's only a few things we wash by hand and I just balance them on the stainless steel bars to drain.

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## HigherPlane

Thanks Guys 
djsherly - I just got them from Bunnings mate, it's in the section with all the concrete additives. 
Godzilla73 - They are 60mm thick. I don't think you would want to go much thinner than that otherwise strength could become an issue. You could make them as thick as you wanted, however they would get heavier (the biggest of mine weighed about 180kg). Part of the attraction though is it's sense of mass and unlike grainte there's no join line where they have put two 20 mm pieces together to get a 40 mm edge. For the joins I used marine epoxy and colour matched it with the same pigment as I used in the concrete.

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## HigherPlane

Hey Steve
Bit of a late reply sorry. I did use what you are talking about to make these (high gloss MDF). I don't think it would make much of a difference with the parts you polish with a wet grinder (it would only take a few seconds for 50 grit to smooth off the normal bumps you get on standard chipboard melamine). Where i think it did make a difference was the sides where I hand polished the edges. Don't even think about getting a terrazo finish on the sides, as you have to hand polish them - the wet grinder, as well as making an almighty mess, would chew the edge up.

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## Pitto

Mate, hats off to you, your kitchen looks fantastic. Being in the commercial joinery trade for the last 8 years and mainly being exposed to PF and stone tops, Your Concrete tops look great. definately a material that is understated thats for sure. 
I was just looking into Chengs website yesterday. I have an outdoor kitchen/BBQ/Bar for home to do and i was thinking of using stainless legs on HD castors, Ecopanel for the carcases and maybe a Concrete benchtop.

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## HigherPlane

Cheers Pitto, it's nice to hear that from a tradie. Cheng was probably the most informative of the books I got my hands on. I'd recommend buying a book as there's quite a few hints they have that the videos don't go into. You should be able to pick them up pretty cheap second hand on Amazon or something. We are thinking of doing a similar thing outside with a pizza oven etc. Putting it all on castors sounds like a good idea if you want to move it around (or even move house). 
Cheers
Matt

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## twistedfuse

New to this forum but couldn't resist registering and saying WOW!! The countertops look great. Personally just starting to get into decorative concrete and they are very inspiring.  
Been doing alot of reading online but realise that i will probably want to buy the books and dvds available so if anyone has out read/watched their copies of Buddy Rhodes or Cheng Books/DVD's i'd be interested if they are at the right price.  
Daniel

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## dan76n

Higher plane that looks great.
Can I ask how flat the surfaces have turned out compared to engineered stone?
Looking at the photo from the kitchen over the breakfast bar it seems slightly bumpy or is that just the photo?

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## arms

as with all cast products the surface finish will only be as good as the preperation you have put into it ,finishing is another subject and it all comes down to what tools you have for the job .commercially they would have a gantry finishing grinder then change to polishing stones for the finished product .joe blow will finish off with hand tools and the finish will reflect this but on the other hand a slightly irregular or uneven finish can also enhance the look as its more personal.
eye of the beholder !!!!!! 
Higher Plane .as a side note i am impressed with those bar seats .

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## BaysideNana

WOW....Higher Plane (Matt) that is really nice!!   Imho, you've done a great job on the benches, they look great!!  DIY is so very satisfying isn't it?  all the warm fuzzies and all.  Some years ago my husband and I built our own two storey house, neither of us had any previous experience and the knockers came from everywhere BUT we learned sooooo much along the way it was amazing and, while I know my limitations, I will have a go at most things having thought through the whole process beforehand, so I know how you feel at the end of your kitchen makeover.   
What's the next project?  ....psst, you should go into concrete kitchen benches!!!   LOL     :2thumbsup:

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## HigherPlane

Hey Guys  
Thanks for all the compliments. 
twistedfuse - I'm going to keep hold of my books for sentimatal value. However, if you try amazon and places like that you should be able to get some second hand ones pretty cheap.  
dan76n - it's just the photos the tops are perfectly smooth and flat. You'd find some tiny flaws if you looked for them, however it'll only be the sort of thing you (always your worst critic) will notice. 
arms - you'd be amazed what a $110 wet grinder off ebay can achieve (the pads cost a fair bit ontop of that though). Everybody comments on those stools. I'd love to say I made them, but I think some poor indonesian bloke getting paid a couple of dollars and hour slaved over those beauties. 
Cheers
Matt

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## Pitto

pretty sure next weeks episode of Better Homes & Gardens show a kitchen makeover and i was almost 100% certain that it features concrete benchtops. 
Something to check out next friday night. 
G

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## arms

> pretty sure next weeks episode of Better Homes & Gardens show a kitchen makeover and i was almost 100% certain that it features concrete benchtops. 
> Something to check out next friday night. 
> G

  and no doubt they will give the impression that its easy to do and cheaper than alternative surfaces .the phones/email will be hot on monday with dreamers that believe the tripe that is televised

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## terminal_stance

Hi Matt, great kitchen Reno!! Your bench tops look fantastic.  
Do you know if you could integrate carbon fibers or weave to increase strength and decrease thickness (and therefore weight). Obviously the cost difference is significant though.  
Also would you consider putting glass shards in the wet mix to play with the aggregate look? 
Clearly better homes and gardens will simply tell us to hunt around our old sheds and recycled building suppliers and pick up a preformed slab for extra cheap! 
Good job, 
Tim

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## HigherPlane

I'll have to watch that.  
Cheers Tim. I used fibergalss in mine to increase strength and it's also supposed to help reduce cracking. I've never heard of putting carbon fibre into concrete, it sounds like an interesting idea. I've seen videos of guys putting sheets styrafoam into the block, but I'd be pretty dubious about its strength. To be safe I'd want the reo in there; the problem then being that you can't have it too close to the surface or it "ghosts" onto the surface. Let me know if you find out more about the carbon fibre idea though. 
Matt
'

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## Sargeant Shultz

Hi Matt, 
Your kitchen looks great.  I've been following your thread for a while now and am preparing to pour the 2nd of three concrete sections for a U-shaped kitchen countertop.  Your tips and advice together with Cheng's book have been invaluable - thanks alot for that. 
A few questions I do have are:
1) What specific type of epoxy did you use to secure the stainless steel trivets to your countertop?  Is this the same epoxy you would also use to join abutting countertop sections?
2) After removing your countertops from their form did you use a slurry (cement, water/reducer and oxides to colour match) to fill in air holes or did you use a colour matched epoxy (as Cheng's book suggests)? I used slurry but it did not seem to fill the smaller holes all that well on my first piece.
3) Did you go for a penetrating sealer/wax or a topical sealer?  I used penetrating sealer with canuba wax and if you happend to use the same I was wondering how your surfaces are holding up with hot saucepans etc.  
For those on the forum contemplating making concrete countertops, go for it - you won't be disappointed.  It is cost effective, very rewarding and once you get the hang of it the possibilities are endless. 
Regards,
Peter

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## HigherPlane

Hey Peter 
Glad my threads been a help to you. 
1. I went to a marine store and got some epoxy from there. It was pretty standard marine stuff. I think I remember doing a lot of research into this at the time and in the end result for our purposes was epoxy is epoxy. From memory I think I spent about $80 for somewhere in the region of 500ml all up ie resin and the other part ... forget what it's called. It's a lot cheaper than buying heaps of little tubes from Bunnings. Whatevers left is handy stuff to have around, it's a bit fiddly to use but is the best glue I've ever come across. I used this with a little of the oxides to colour match. Mix the epoxy well then put your oxides out like you see people cutting cocaine in the movies and add tiny (and I mean tiny) amounts to the epoxy mix until the colour match looks about right (take it over to the counter top to compare). 
2. I remember the slurry being a bit of a pain in the @@@@ and usually having to do the process twice to get a good finish. As Cheng says toothpaste consistency and use a mist sprayer if it gets a bit dry as you put it on. Then push it in with a plastering trowel. I used the same slurry mix that you mentioned. Don't worry if you leave a fair bit on the slab it will come off in seconds when you polish again (start at the reasonably high grit you don't want to go cutting far into the slab again). 
3. I just used a penetrating floor sealer from Bunnings. I tried the wax once and found it gave a crap finish - all streaky. I've been relying on the sealer alone and it still looks like new. I don't as a habit put hot saucepans on the countertop, that's what i did the trivets for. However, the couple of times I have, there's been no problem. I left an olive oil bottle on the top for a couple of days once and when I took it off the outline of the base of the bottle had soaked into the top (from oil dribbling down the side of the bottle) leaving an obvious mark. As you can imagine I was pretty pissed at myself, however about a week later the countertop had absorbed it all and you couldn't see a thing anymore. I'm a pretty messy cook and often leave the clean-up for the morning and the tops seem to put up with this abuse. I'm pretty careful (but not that careful) with acidic stuff like lemons and tomatoes but haven't had any issues so far. All up I think these things are very durable. I have had a couple of chips on the edges of the bench tops as I think I made the edges a little bit too sharp. Its probably worth putting a thicker bead of caulk in the mould and have a slightly rounder edge. 
Good luck with the remainder or you project. Put some picks up when youre done, Id love to keep this thread alive with pics of others that have done this.

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## stevoh741

:Jacked:

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## watson

Not on my watch......all GST stuff is now in a thread of General Odds & Sods called GST stuff. 
Keep on topic please.

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## Codebluestar

Thanks for this Aussie friendly thread - I've found it really helpful.  The finish you achieved on your bench top looks fabulous and the before and after shots are motivational! 
Higherplane a couple more questions if you don't mind!  What size aggregate did you use? Where did you source it from?  thanks for posting your mix recipe - but how on earth do you measure it up?  I'm imagining myself in the backyard with my concrete mixer, the bathroom scales and the kitchen set too!  I assume getting this accurate is important for consistency between pours. 
Do you have any idea on how far you might cantilever the concrete slabs before you can see that they bend?  I'm guessing that this is a function of how much reinforcement they have. 
I've checked eBay for stingers and wet grinders as they seem to be what I'm missing from your list. Could you post some more information about how long you vibrated the concrete for? Did you move the stinger around? Did you Jerry rig a holder for the hand held version or buy one that came with a clamp? 
Thanks for your generosity in sharing your knowledge. 
Codebluestar

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## HigherPlane

Hey Codebluestar 
I the aggregate I used was about 10mm bluestone (although some of it came up green). I remember reading somewhere the important thing is to have a variation in size (from a strength perspective). It's just road base so you can get it really cheaply from one of those landscape yards. I think I spent about $50 all up for the white sand and bluestone at one of those places (might have even been less than that). I did what you suggested you were thinking of doing with kitchen and bathroom scales - don't make that mistake it was a nightmare! Add to that, half way through my sand and aggregate got rained on therefore waterlogged and heavier! I would base everything off volume rather than weight if I did it again ie 4 buckets of aggregate and 1 bucket of sand and .5 bucket of cement etc makes X amount of concrete. If I did it again I'd try and keep it as standard as possible ie have a recipe based on volume similar to what I just suggested and stick to it, even if it means throwing away 30% of the mix for a slightly smaller bench top (the ingredients are pretty cheap). I hope what Im saying makes sense - it does in my head at least. For a couple of the bigger pieces I needed to do more than one batch of concrete in the mixer (I couldn't find a cement mixer that could handle 180kg). There is one piece I made were I must have something up because it's a slightly lighter shade than the rest. Saying that though I'm the only person that has noticed it and I don't notice it anymore anyway. 
My cantilevers are just over 300mm. I you wanted to go much more than this it might be worth trying to find and engineer or maybe a website that has a formula for calculating the maximum. I would imagine they could handle a fair bit more than 300mm (assuming you have lots of reo in there) but I couldn't be sure. My worry would be somebody sitting on the end of the cantilever and putting a huge crack somewhere near the pivot point. 
I made a bracket out of wood and clamped it onto the bench ie the whole bench vibrated. I don't know if this is normal for stingers but I had to give mine a tap on something hard to get it vibrating. This meant I had to clamp it to the table a while it was vibrating - not a task I have fond memories of. If you've got tools for metal work or you can buy something readymade do this as my wood bracket barely made it. Those sliding F-clamps won't work if the stinger is already vibrating as the just get shaken of their ratch thing before you can tighten them - c-clamps worked for me. Don't bother trying to but the stinger into the mix unless you enjoy the prospect of having the surrounding 5 meter area covered in your nice concrete mix. From memory I vibrated for a few minutes or a least until bubble stopped coming to the surface. You don't want to go too long or apparently too much of the aggregate sinks to the bottom. 
Good luck mate

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## David.Elliott

Hi All, new member here...
We're going to do the concrete thing too!
Wifey's doing all the research and pointing(!) I am supplying the brains and brawn.
Couple of question if I may, cannot seem to find an answer to the fibres question, glass or nylon, and where from...?
We did however find the following product available ex USA which we're going to order in and try. Concrete Countertop Forms, Kits, Supplies | DIY Concrete Countertops
They have various edge profiles for "Cast in Place" Countertops to give a fancy edges. Looks really easy in the video? 
David

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## bowseruni

do you have any better pics of how you cast in the slope bit and stainless bars?
looks tops

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