A sheeps foot roller only earns its rate when the soil is near the right moisture, because feet knead a lift rather than press it, and clay too dry to knead will not compact at any number of passes. Yards supply those feet in three shapes: a walk behind trench roller, a ride on padfoot machine, and a bolt on shell that wraps a smooth drum. The width of your fill picks between them.
Moisture decides whether the passes do anything
Cohesive soil compacts in a narrow band either side of its optimum moisture content. Too dry and the clumps stay clumps whatever the machine does. Too wet and the fill pumps under the feet and never gains density. If the job has a specification behind it, someone tests for that number rather than judging it by eye.
The shell kit that turns a smooth drum into feet
Many yards stock a bolt on padfoot shell that wraps the smooth drum of a roller they already hire out. It is cheaper than a second machine, it converts a single hire when the soil turns out to be clay rather than sand, and it comes off again for the finishing passes. Ask whether the yard holds one for the machine you booked.
Towed feet behind something you already have
A towed padfoot drum has no engine and no cab: it hangs off a dozer, a tractor or a loader and is ballasted by filling it with water. On a large fill where a machine is already working, that is the cheapest density on the site. On a narrow trench it is useless, because nothing can tow through the gap.
The three shapes, and what each one bills
A remote controlled walk behind trench roller commonly runs about $200 to $350 a day. A shell kit adds a modest daily line to whatever roller it fits. A ride on padfoot is the expensive one and generally comes with a longer minimum hire and a lowboy delivery, since none of that class travels behind a pickup.
Questions people ask about sheeps foot roller
How many passes does a sheeps foot roller need?
Commonly four to eight over each lift, with the last pass showing the feet walking out of the surface rather than sinking in. That walking out is the field sign that the lift has taken density. If the feet still sink after eight passes, the lift is too thick or the moisture is wrong.
Can I use one on gravel or sand?
Not usefully. Granular material has no cohesion to knead, so the feet simply displace it and leave the surface loose. Sand and gravel want a smooth vibratory drum or a plate compactor. Mixed fill is a judgement call, and yards will often hire the shell kit so you can switch on site.
Does the machine need an operator on it?
The walk behind trench class is remote controlled from a belt box, which keeps the operator out of the trench, and that is much of its value. Ride on padfoot machines are seated and want someone competent, especially on a slope where an articulated frame behaves differently from a rigid one.