Sunday, November 18, 2007
Excavation of floors with mini-digger.
This week we have mostly been digging out the mud floors.
Hiring the digger was something I've been putting off because the whole operation seemed a bit daunting and I've never driven a mini-digger before. I was also a bit concerned about digging down too much and undermining the foundations. After clearing the two areas of the building of stored materials and rubbish, each around 35 square meters, and shopping for various bits of pipework etc, to go under the floor on Monday and Tuesday, the digger arrived on Wednesday. The day of reckoning. Along with the digger we also ordered two conveyor belts to remove the spoil.
The preparatory work involved marking a line around the walls one meter above the finished floor height so we could dig down a further 40cm. Thats for the tiles (1cm), concrete floor + iron grill (10cm), insulation (4cm), waterproof membrane + sand (5 cm) and hardcore (approx 20cm) in that order. 100mm soil pipes are buried within the hardcore at the correct fall.
The delivery guy arrived in the morning with the digger and gave me about 30 seconds instruction on how to use it, half of which was pointing out the key, where to fill up with diesel and a reminder that we only had eight engine hours per day on the counter. He was gone and I was on my own with more levers to push and pull that I knew what to do with. It took about an hour and a half to get even moderately proficient at the controls. It reminded me of learning to fly my model helicopter as a kid. Coordinating all the levers simulanteously in three dimensions was not easy.
We had only planned on hiring the equipment for one day, but with the learning curve and problems with the conveyor belts only the first section was anywhere complete. We had not even started the second room. The conveyor belts seemed like a really good idea but I'm not sure they were worth the trouble (and cost). Firstly they were very very heavy and difficult to move, so generally we made do. Secondly the mechanism around the rollers kept jamming with small stones and mud, halting progress infuriatingly often. Thirdly the spoil at the far end had to be constantly raked clear to avoid the heap building up around the end of the belt and fouling the belt. If we could have positioned the far end of the conveyor 10m up in the air it would have been great, but, see reason one. With hindsight it would have been just as good to have two or three willing volunteers with wheelbarrows.
Anyway, perseverance and a late night on Thursday got 80% of the job done and the hire shop was due to collect Friday. We had only used 14 of our 16 engine hours but crawling around on your hands and knees dismantling the jammed conveyor belt by torch light was enough for the day.
With luck the hire shop didn't turn up until after lunch on Friday so I got to use the 2 remaining engine hours and clear most of the mud from the second room and tidy up the site.
Something that was a little strange, and slowed down progress, was that one room was just compacted mud for the full 40cm, but the other room was piles and piles of stone. It looked like sometime in the past one, or possibly two, chimneys had been dismantled and all the stone buried in the floor. Digging out tonnes and tonnes of blackened stone proved really tough going and really needed a bigger mini-digger.
I haven't got the bill yet, but it's going to be about 900 euros for two days hire, so if a professional digger driver offers to do the same job for around the same money I'd take it every time. Even better if they take all the waste off-site. I've no idea what I'm going to do with 25 cubic meters (25 tonnes?) of rock and mud.
Here are a couple of movies or the mini-digger in action and the conveyor belts.
| 6:57:56 PM
brittany
renovation
Excavation of floors with mini-digger.
