Some advice about concrete

#21

how would latex self-levelling hold up to this, I wonder?

#22

PLEASE be careful with this. Concrete and high heat sources do not play nice together. Rapid heating of concrete to a high enough heat will cause water droplets in it to turn to steam, resulting in explosive results.

I’m sure a hearth would be OK, but something to consider.

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#23

I was thinking the same! the two part one from topps tiles is the best one i have used
https://www.toppstiles.co.uk/tprod41870/ultra-level-it-2-powder-part-1.html
https://www.toppstiles.co.uk/tprod41871/ultra-level-it-2-liquid-part-2.html

retail £35 i can get it trade for £21.60

#24

Ah that was actually my original idea to put the wood at the bottom and pour the concrete on top. But I wasn’t sure I’d get that smooth finish I wanted. But if you think a trowel would do it?

@peter_hellyer and @lewisss that stuff looks like it would make a really smooth surface using that technique above. Although does it actually look and feel like concrete? Looks a bit too shiny in the google images I’m looking at. I guess I’d need to inspect it in real life.

#25

light trowel and it gives a perfect smooth surface not sure if it will be strong enough though

#26

Mark, any clue as to the specs of the compressor?

Need minimum 5.1 CFM at 90 PSI

#27

Those dates work for me. I have a small bag of cement, will post picture soon. Happy to share it.

Silly question, dont we need some aggregate to mix on? Sharp sand?

Btw pigments are available if you want white or black concrete.

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#28

@Matine just doing some sums and it’s gonna be pretty expensive to get all the stuff needed for the GFRC. Maybe difficult in such a short space of time, so if you have other, cheaper options I’d go with those for now.

Still want to have a crack at doing this, just may take a little longer to get the items together and garner interest and/or pledges etc.

However, happy to have a crack at traditional casting in the meantime. I may be around those dates to lend a hand. It’s all a learning experience I suppose.

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#29

#cementcastingfail too many cracks

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#30

Mr Thesaurus today, ain’t ya?!

#31

I asked around, that’s the word on the street. Watch your back (cover).

#32

imagehttps://giphy.com/gifs/picard-1PIGU0cftC2pG

#33

Yeh I think you’re right. It may be a bit overkill for this particular project, particularly since I haven’t worked with concrete at all before. But I am very interested in the GFRC and would like to help out when you decide to do it. And if all goes well with this I’m sure I’ll be doing more concrete projects anyway.

Think I’ll be going with “A melamine or similarly shiny finished board” (cheers @Nick_Milburn) for the mould and the edges to be the exact height of the thickness I want (around 18mm). The sheet material (around 12mm thick and a 5mm gap around the edges) I’ll put on the base and pour the concrete over (smoothed with a trowel). Just need to work out which type of concrete will work best and maybe do some mini trials.

I’ll still be doing it on those dates if anyone wants to join let me know and I’ll give you a shout.

All this info has been reeeeally useful. Thanks so much all!

#34

i have somewhere at home a concrete vibrator (no comments from you smutty types ) to take all the air bubbles out, i will have a look

#35

orbital with no sandpaper on works well…apparently

#36

Thanks for giving me a laugh. It really is the best medicine

#37

Ohh i was interested in GFRC at one point but it looked like too much faff for one project.

I wanted to make something like this https://www.wayfair.co.uk/Lyon-Beton-Wall-Mounted-Toilet-Paper-Shelf-DB-09120-L6143-K~LYBN1005.html?refid=GX200082349414-LYBN1005&device=m&ptid=324963990163&network=g&targetid=pla-324963990163&device=m&gclid=CjwKCAjw0ujYBRBDEiwAn7BKt79-F1qVpcTAbrdi0z3zONUoKovO6M1xXgX5ccypNTPFrWoQYwNjNxoCeEoQAvD_BwE

#38

I’m definitely gonna have a bash at it. I’ll give you a shout when I’m up and running. We may have some economies of scale going on by then and will also hopefully have worked out how to do it properly.

#39

Hi I’m free evening sun and Tuesday daytime and evening

Want to work together?

#40

I might be able to get my hands on small panels used for cupboards with solid Formica style laminate. These would be good for making small molds

Should I bring them over ???

Need to know ASAP as they are destined for landfill otherwise.

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