On 19 Apr 2004 10:59:08 -0700, snipped-for-privacy@yahoo.com (Don) vaguely proposed a theory ......and in reply I say!: remove ns from my header address to reply via email
A warning with all water levels. You must not have any air bubbles in the line. It can stuff everything up. The same goes for any rises and falls in the line, as these will probably create air bubbles.
Such is my experience. I had wrong readings because of air bubbles.
I _believe that if the air bubble occurs _and the water levels are already exactly equal, and you don't alter anything_ then you are OK. Any change with an air bubble and you will get wrong readings.
IME.
As far as the actual levelling goes, depends what you have. I have done them with shovels and string lines, working in smaller squares to keep the scale down to size. I also use a scrape stick once I am close to get larger areas of flat.
But I would use a compactor very thorougly, then re-level, then recompact, expecially if you are going to cement/brick/pave afterward. Also remember that string lines stretch and sag. They need to be _tight_..did I say _tight_? The better the job, the less cement you need.
My FIL was a commercial grano worker, and used shovels, but had a dumpy level and used to place a perimeter of oregon planks , with spikes in the ground every 2 metres' square or so, and work around those. The spikes were very accurate (woe betide any poor bastard that kicked one! DAMHIKT) and stuck up the expected depth of the cement, say 100mm. When they laid the cement, they would simply work to the top of the grid of spikes.
The box grader is a good idea, but takes some skill to get really nice. I would still be finishing with a shovel.
And compact compact compact. This will increase your workload, but you will not regret it.
My dream is to have a layout that allows a really heavy bar or some such to be dragged across the top of levelled rails either side, simply levelling, then comnpacting and filling any missed bits, then again, and again, maybe working in strips. I have about 4 big pads to do at least, where I am, so it may be worth my while.
**************************************************** I went on a guided tour not long ago.The guide got us lost. He was a non-compass mentor.........sorry ........no I'm not.