Trailed post driver that makes do with a ‘small or elderly tractor’

The latest innovation in fencing equipment from Scottish company Bryce Suma is a post driver that can be operated by a tractor of “modest size and weight”.

Jock Bryce of the Kelso-based manufacturer points out that, normally, Suma heavy-duty post drivers carried on the rear three-point hitch need a “substantial tractor to maintain stability on-site and during road travel”.

Trailed design

“But not everyone has need of a 120-150hp tractor, so our new Suma TR400 is a trailed design that can be operated by a small tractor, whether new or quite elderly,” he explained.

“As long as the tractor can summon up a 25-30L/min oil supply to operate the 400kg hammer at a sensible speed, then that’s all you need.”

The Suma TR400 has the added benefit of storage space for up to 20 strainer posts, 100 round or square fencing stakes or eight to 10 rolls of 100m net, plus barbed or plain wire.

The chassis houses a container for a chainsaw and other hand tools. There are tool trays for fencing gear on the drawbar and adjacent to the hydraulic controls. There are vertical slots for storing wooden support blocks (to place beneath the two stabilising hydraulic jacks).

These extend from the frame by the off-side wheel and from the bottom of the mast, as part of a package of hydraulic features that also provide mast side-shift and two-way vertical alignment.

Back-shift and side-shift enable the operator to “precisely” position the mast (for driving fence posts) or the patented integral hydraulic swing-around rock spike.


In addition, the drawbar design allows the chassis to be ‘jack-knifed’ at up to 90º to the tractor to get into tight or awkward corners.

As on all Bryce Suma post drivers, the mast on the new TR400 is a two-stage telescopic design that provides 3.6m of hammer drop (to strike the steel cap that holds and protects the post).

“The unique and patented ‘auto tele mast’ provides the operator with a choice of any length of hammer stroke, without having to make any adjustments to the mast itself,” explained Bryce.

It also reduces overall height to avoid overhead cables or branches when working amongst trees. For transport, the mast is set at an angle to further reduce overall height and bring the weight inwards.

Other patented features include a greasing arrangement that allows both sides of the telescopic mast to be lubricated without the operator having to clamber onto the machine’s frame.

Bryce Suma has tested the new machine on a modern 47hp utility tractor, a regular 60hp farm tractor and on elderly 2WD and 4WD tractors, which can be fitted with an auxiliary tank and PTO-driven hydraulic pump if their built-in hydraulic system is inadequate.