A grinding we shall go

It's taken a few months to get them onsite, but finally the floor grinders are here! Actually that's not strictly true - they did show up unannounced a month ago or so, and were unable to get their equipment into the building so gave up, and drove back to Shepparton!

But they're here now, and so with a little assistance with the bobcat we've got their gear inside and they're getting stuck into the floor.

Who took this photo!? Focus!!

A couple of hours and about 4 passes with 60 grit stones later, and there's still very little aggregate showing yet. What is coming through is very fine, as if the mix was a grout using 7mm rock - but I've checked the records, and it was definitely 32MPa mix with 20mm aggregate, so it's in there somewhere!

Rather than spend all day grinding with the finer stones, they've switched to the heavy duty stuff and now we're getting somewhere! These ones are leaving some pretty impressive scratches in the surface, but they're eating away and the aggregate is starting to show itself.

Another couple of passes and one more with the finer stones and I think we're there.

I'm pretty happy with the result - it's taken a while (and the job is only half done) - but I think we'll have a pretty nice concrete floor at the end of the job.

The grinders are coming back on Monday to give it one more pass to get rid of the coarse scratches, then it gets grouted to fill in the little air bubbles and cracks, and a coat of epoxy goes on. Then I can get stuck into the wall lining, and once that's finished they'll come back for a final polish and seal.