Cifarelli Harvester - team Denton modifications
Main points are:
- The original unit is too heavy & cumbersome for convenient & continued use as a backpack, so I have put it on wheels. (And removed the shoulder straps and padding.)
Construction is light but strong to keep weight down. Wheels are big enough (width & diameter) to roll easily over uneven ground. The draw handle has a stop position to prevent it dropping down to the ground if the operator releases his grip. It is held up at a convenient height to grasp again without bending down.
Putting the unit on wheels has the additional advantage of placing the operator a little further from the motor, reducing exposure to exhaust fumes and noise. (However, it is still best to use earmuffs.) - I have incorporated a plywood tray underneath which can hold a crate. Release of the nut chamber allows nuts to fall directly into the crate.
- The leaf discharge tube has been replaced with one which blows leaves to the left rather than down to the ground. This allows the operator to work the block from the outside in a clockwise direction, always blowing discharged leaves to the outside of the block ie onto the already harvested area. This is a convenient direction of travel. A right-handed operator will automatically pull the cart with his left hand and hold the suction tube with his right hand.
- The flexible suction tube, although of suitable length for the backpack, is too short for the wheeled model, so I replaced it with a longer hose. It allows me to work a reasonable width swathe. In replacing the hose I took the opportunity to slightly increase the diameter because the size provided was difficult to slide onto the plastic suction tube and onto the main unit.
- I reposition the stop/start switch and throttle control so that it was on the same side of the unit as the starter cord and choke control. Much more convenient for starting.
- The petrol tank has an angled filler spout which is most inconvenient for filling. So I remounted the tank onto an angled mounting which means that the spout is now pointing straight up. Also, the filler cap tended to leak (perhaps a bad thread design?). This is an annoying and dangerous feature of the unit when used as a backpack. Remounting the tank has removed the leakage problem too.
- Sometimes small twiggy branches are sucked up, and these have a habit of lodging at the point where the suction tube enters the chamber. If they lodge there, leaves build up against them, eventually stopping the air flow. They are particularly hard to dislodge. I found they could be dislodged by removing the rigid plastic suction tube from the flexible tube and poking in a long plastic alkathene pipe – another annoyance to the operator. So I have incorporated a stainless steel easy-release coupling at the point of entry into the chamber. This has 2 simple over-locking clips to hold it on, and I have added a clamp to give the stainless steel attachment extra support onto the frame of the wheeled unit.
Evaluation
I have gathered my hazel nuts with the modified unit last autumn and am absolutely delighted with the result. The basic unit is of excellent functional design – it is easy to start, and works well in separating out the leaves. However, it did need practical experience of use in field conditions to show what modifications were required to make it convenient to use, and I find it not too tiring to use all day.
Notes courtesy of Maurice Denton, from a hazelnut field day at Wairata Forest Farm, March 2008