For those of you who remember, last spring I was contemplating the purchase of a rotadairon. (see link) Here is an update and a product review. http://lawnsite.com/showthread.php?threadid=46686 Last fall I bought the rotodairon. It was a big decision because they are expensive compared to other 3ph attachments. ($15000 can.) Shop around a bit because the price can vary by over $5000 depending on the dealer. I used it all fall and am very pleased. My work turned out just like the pictures on their website. Flat, smooth lawns in one pass. Little dimples to stop the seed from washing away. No rocks or debris to haul away. http://www.mge-dairon.com/presentation_rota.php?langue=en The rotadairon is several tools in one. It is a tiller and can be used to loosen compacted soil, incorporate compost or topsoil, to dethatch or to bury debris. The rotor (tiller) can also be used to level the surface with skim passes. The selector screen separates the good soil from the rocks, clods, clumps and other trash. The unwanted debris is buried underneath a layer of good soil. A NIV grader blade levels and lightly grades, dragging soil from high spots to low ones. The rear roller packs everything down and leaves dimples for the seed to sit in. I am using the RD 100. 40" working width. Tractor is a New Holland TC33D. Powers it pretty well and covers one wheel track. Digs 5.5" deep. Pros It is a solid piece of gear and should last a lifetime. Fairly easy maintenance, grease fittings and changing fluids. With a rotadairon you will never have to remove debris, old sod, stones or leaves from a site. It chews it up and buries it. Old lawns are pulverized, shredded and then buried. Best to leave the organic matter on the site. Another plus is that some of the stolens and rhizomes that get left near the surface actually will grow again. This thickens the lawn up even more. It seems that most broadleaf weeds were effectively buried and did not reappear. Of course I may have unearthed millions of more seeds by rototilling but anytime you work the soil new seeds get exposed. Bumpy lawns: Aerating, dethatching, leveling and rolling all in one pass. One day while playing around with the depth settings I discovered that by setting the depth to between 0.25" and 1" below the surface I could effectively dethatch a lawn. The rotadairon did not bury the thatch but kept kicking it along the surface until I could windrow it. The teeth also chewed off the high spots (bumps) and filled in low spots. The rear roller then packed everything back down. Very effective for heavy duty dethatching without renovating the whole lawn. Worked well when I aerated before dethatching so that the rotor could chew up the plugs and fill in low spots. Extremely rocky areas: One day while doing an extremely rocky lawn I discovered that the 5" of "topsoil" that the house contractor had installed was actually pit run. (Sand and Stones) There was nothing I could do with it as the large stones were clogging the machine and the millions of smaller stones had no where to be buried. The homeowners had spent days picking stones to no avail. They kept coming up. Since there was no more money to bring in real topsoil and I was not too keen to break the rotadairon hitting rock after rock so I found a compromise. By setting the depth to about 2" I could loosen the soil but instead of burying the rocks, I kicked them along the surface and collected them. (Think Harley power box rake) This gave them a rock free seed bed that could be planted so the kids would not have to play in the mud all summer. Another bonus, it is a different piece of equipment with fantastic results in one pass so it draws a lot of attention. People actually stop by to watch, ask questions, which leads to more jobs. Cons There is a bit of setup involved. Setting the tiller depth, adjusting the "grader blade" and shifting the roller left or right. Different soil types require different settings. It does not take long with a bit of experience. It does not grade as well as I had hoped. I still use my bucket or back blade for any major grading. It will fill in minor flaws with its NIV grader blade. (Still not sure what NIV means) I also should have opted for the cast iron packer roller ($2000 more) The mesh roller is too light and the soil does not get packed enough to walk on (for seeding, sodding or fertilizing) I will be fabricating my own cast iron packer roller this spring instead of the standard mesh roller. Sometimes, when I was done tilling, I would lengthen the toplink which would raise the tiller out of the ground and put more pressure on the roller. This worked well for packing the soil down a bit more. I could have bought the seeder kit ($5000 extra) but did not anticipate the lack of packing. I use a broadcast spreader if I'm not sodding or hydroseeding. It would be nice to be able to seed at the same time in one pass especially having the rear roller to bury the seed but I'm still choking on the price of a metal box. Might make my own if I feel creative. Large rocks(4-6") DO NOT go thru the rotadairon and the sound produced is terrible. It is handy to have someone around to remove these ones for you after you have unearthed them and pulled away. Of course, about one month after I purchased it, I was at a farm show and found a cheaper, knockoff for about $9000. It was not as well built so I'm glad I went with the original. Rocks smaller than 0.25" -0.5" MIGHT pass through the selector screen but by putting some garden hose on the rake screen, you can filter down right to the smallest of stones but you have to go slower. 0.25"-0.5" is a pretty small stone anyway. I'm still curious about other options like the rockhound and the Harley landscape rake of course, but neither incorporates compost or soil like mine does, although they might grade better. Different tools for different jobs. Mine works better after the grader/bulldozer has been in and I'm just installing the lawn. The soil is perfect after one pass. I plan on renting a Harley to see if there is a difference in the grading performance. Other machines that might do something similar but about which I could not find much info include: kora topmaker, Incorporator, Rockhound, Blecavator, Superake, power harrow and the laser leveller. If you could get work for a house construction contractor that would be ideal. Putting the final finish on the property. In conclusion, the rotadairon has really improved the quality of my work and allows me to do it a lot faster. It can do many different tasks quickly and with good results. It fits in well with my other equipment and really reduces the amount of hand labour required to do a job. I'd buy another one. Summary cultivate to a depth of 5.5 inches bury stones, clods, grass and debris create a fine soil surface for accurate seed depth and ideal turf renovation clean seed bed free of weeds and trash level and finish the surface seeding roll firm from 800 to 2000 lbs depending on the equipment Quotes from dealers that sell the rotadairon. These 2 pictures are close-ups of the soil just ahead of sodding. Note the small amount of organic matter remaining on the surface. Being able to "turn under" the old grass has several advantages. The organic matter of the old grass helps improve the soil structure. Not having to remove the old grass saves a substantial amount of money. Removing the old grass on an athletic field costs more than buying new sod and having it installed! Using the Rotadairon process, existing soils can be amended with a variety of materials in order to build up the soil and create a uniform consistency. The process creates a soft seedbed that is easily penetrated by new seed while at the same time burying rocks and sticks. This process has been used in Europe for many years. This process has the potential for significant cost savings over trucking in new topsoil.