Concrete advice.

[cumbriasteve]

Yes nothing to do with steel and welding but this forum has proved time and again it has a wide range of expertise amongst it's members...so here we go:

Relative has had a drive laid 2 days ago, being a bit strapped they have used a cowboy firm and the results show that.

it is covered all over with deep float marks, some as high as 25mm.

I can remember my garage floor had some and I rubbed a brick over them, it worked well and flattened them back but I think I also read somewhere you can pressure wash a newly laid drive to 'polish' it and remove float marks.

Will it work? or is there any other non costly method apart from that and the brick method.

 

[garethp]

Sounds like you've nothing to lose by trying it, the longer you leave it the harder it'll get. You can also hire diamond floor grinders or get just the wheels for handheld grinders

 

[julianf]

id be pretty scared of pressure washing new concrete, esp if the mix may not have been even

 

[brightspark]

if its still green rub the top off mix a cement slurry up add some sbr bonding agent and float it over, just get a mush on before it fully cures

 

[Rig Pig]

I have used a brick - the type used for brick weaving as an abrasive block to sand down concrete to remove lumps and bumps, it works surprising well.

 

[normspanners]

it is covered all over with deep float marks, some as high as 25mm.

float marks !! sounds more like shovel marks, 2 days you will be struggling, you could try a large concrete block with two people, I did some with a concrete block with two people and rotated it, back and too, with water,but not loads just so the holes will be filled with the fat you make, like grinding valves in, thats ok if the trowel marks are just the concrete 'fat' as it is called, big problem if there is aggregate in the lumps and you pull the stones up. i dont think a pressure wash will work.

 

[Pete.]

Whatever you do get a move on. At 2 days old you're looking at mechainical work though I think. Hire a floor plane, a little push-along machine with a flail of tungsten-tipped rings underneath. Should be easy work for it if the concrete's less than a week old.

 

[cumbriasteve]

Cheers Folks
Looks like that's my day planned tomorrow, so much for having an easy day

 

[500e]

How Cowboy

or

If latter try to get them back 25mm is beyond bad

 

[cumbriasteve]

,

How Cowboy

or

If latter try to get them back 25mm is beyond bad

Wish it had been the latter.

Got them back today and with the threat do something or we will be looking at court action, got a lot of money back off them so that's not too bad I suppose.

I think with a bit of work I can get it looking half decent.

Tried a brick on an area and it rubbed it down easily enough, 3 of us and a days work should sort it to some effect.

 

[BrokenBiker]

I laid a drive and customers neighbour had similar issue with theirs but not as bad, I went over it with a stone grinding disc in a 230mm grinder. Wasn't perfect but they were plenty happy with it

after 2 days its going to be fairly hard now

 

[ford34/2]

Local hire company, hire a concrete flat grinder, comes with a diamond disc, wont take you long and can probably grind it wet and save all the dust. Professional tool, professional result. Last one I had was a glorified angle grinder. I used it to remove some concrete off the floor when the doors opened.
I made four individual doors to fit into a very old existing frame, The fram looked to have been made with an Adze, still all the cutting marks. Visually they look 4 identical doors--Nowt as lucky, Radius etc was not identical at all. Sadly despite the best care in the world, two of them caught the floor when opened, and the special hinges didnt work to self close them- hence the concrete grinder.
Stan

 

[cumbriasteve]

Yes I may look at something from a hire company if needed, will see how tomorrow goes, shame they did not save a bit more money up and get the job done right first time, always a headache trying to make good a bad job.

 

[Old Dog]

How hard repairing the job will be, depends on what was in the mix and how good the mix was, if it was a weak wet mixture it will be soft for a longer period of time. I had the same problem a few years ago, but it was my own fault, forgot to fence the wet concrete off and the 61kgs dog chased the cat through it!!!!!!! that took some sorting out.

 

[eSCHEn]

Wanted to say thanks for the tip about rubbing down with a brick. I laid my shed base on Sunday and it took longer than expected so ended up tamping in the dark. The few float marks I missed took no time to get flat tonight

 

[Rig Pig]

Glad it worked for you.