Concrete Counter Experimenting

gutteruu

I've nothing to add, just wanted to say nice job. That came out really well. That red sand sample would get me thinking. I had ideas for an outdoor-ish counter.

Andrea B.

Sorry for being so late back;

-Watch this vid for the templating and border process only.
https://www.youtube.com/watch?v=TG0F7Qe4MzM

-As the strips purchased could be costly, I used a plunge skillsaw with rail to cut my own strips from 3x2 timber.

-I would not get hung up on the silicone.
A clean application, rubbed smooth with finger.
-If you want curved corners, see my solution below with superglued hotel key cards.
-To prevent concrete from blocking screw heads and to allow them to be reused, I put a dab of silicone on heads.

- For steel, I suspended the bars using wire as shown in image. Note that this was a breakfast bar with overhang.
The bars should be clean and dry and away from surfaces or userfacing sides, in case of seepage.
For a small vanity unit, they may not be needed.

-If you are leaving a recess for a sink which is straight edged, use the melamine borders. For an irregular shape, a portion of 40mm deep Kingspan would likely do.

-For the red sample I showed previously, I have images of the B&Q materials I used.
Cement:Sand:Pebbles / 1:3:1
A nice porridgy mix poured in to centre and allowed to flow out to sides.

-Vibration around edge with a hammer drill, 12 inches apart for approx 30 seconds to release air. Do not vibrate from underneath, as apparently it can leave shatter marks in concrete.

-After 4 days remove moulds,
-After another day, flip concrete and wet polish through the grades.

-Last image is the breakfast bar after been dropped in. It is still wet and has a few amethyst stones which I had superglued to melamine.

- It took about 4 days to dry fully before sealing with Tung Oil. I am on my thrid coat, which is probably overkill.
-IMPORTANT. Do not place any items on concrete before sealed. It will soak in and blemish from wood, cardboard, hands...whatever.










Best of luck and please keep posted and come back with any questions!!

oojohoo1

Hi, Just wondering what method did you use to keep holes free for the water faucets?

Andrea B.

oojohoo1 wrote: »

Hi, Just wondering what method did you use to keep holes free for the water faucets?

Hi. I didn't. The faucet is mounted on the sink.

fully floating

Thanks for all the tips, think I'm ready to give it a try just have to get all the bits together think I have managed to source everything so far except the polisher, I have a metabo polisher that will spin at max 4500rpm do you think this may be to fast it would probably be the top speed on your polisher.

Andrea B.

fully floating wrote: »

Thanks for all the tips, think I'm ready to give it a try just have to get all the bits together think I have managed to source everything so far except the polisher, I have a metabo polisher that will spin at max 4500rpm do you think this may be to fast it would probably be the top speed on your polisher.

Sorry, I cannot say for sure.
I assume it is wet?
So easy to do trial samples using rigid plastic packaging as moulds.

slavedave

Nice job on the worktop! Good to see someone other than our USA friends making concrete worktops.

Building an island worktop this week. I sourced white cement, limestone sand, silica sand and white marble 10mm aggregate from Goodwins (also some ladder wire from them for reinforcement). Everything else I sourced from Cemcraft in the UK (an online supplier) - fibres, microsilica, white pigment, Super platiciser and sealer. Broken glass was sourced from a tv stand.
Did a test piece from just cement, sand, glass and aggregate a month ago and it looked fine so decided to go " the full monty" for the worktop.

Cast the concrete yesterday and used large buckets and a mortar mixer from Lidl to make three batches of concrete. First batch was the "face coat" containing the glass, some gravel aggegate and a little bit of broken mirror. Next two batches were backing coats where i substituted marble stones and gravel for the glass component, plus I added the fibre glass to thesebatches. Absolute nightmare to work with in large batches (up to 40kgs) even using the superplasticiser and microsilica (which are meant to make the mixes more flowing). I had planned to make a worktop 1.5 inches deep - not necessary when using glass fibres as reinforcement but I was going down the "bib and braces" line with it. After slaving through the batches I made, I couldn't face mixing a full fourth batch so ended up stopping at just over an inch thickness.

The first "face" coat was very "dry" using the calculate proportions but I cast it in any case, but I ended up adding more water than initially calculated to successive batches just to give me a workable mix. I suspect this will weaken the concrete as a result. My key learning is that I would hire a cement mixer next time because the Lidl handheld mixer, though promising, developed a fault and kept not responding at the most critical points of blending. I would also dose in more plasticiser next time as well.

Will have to wait to see what it turns out like, but I would encourage everyone to at least have a go. I would also think that having two people working together would make things a lot easier.

There are loads of good resources online but it can become a bit daunting because there is so much science involved at times. Well worth spending a few evenings watching beautiful concrete tops being made to get the juices flowing!

stickman1019

I know it’s a long shot but anyone have any interest in resurrecting this thread??

stickman1019

stickman1019 wrote: »

I know it’s a long shot but anyone have any interest in resurrecting this thread??

I did a bit recently
https://www.boards.ie/vbulletin/showthread.php?p=114229685