The time before the Venetian frame

Sawing boards with muscle power

In the past, trunk saws were used to cut tree trunks lengthwise. A trunk saw is a frame in which a long saw is fixed. The trunk was placed on a sawhorse for sawing. One worker stood on the log and pulled the saw up empty, a second or even a third stood on the ground and did the actual sawing. These were also called “ abizahrer „.

In England, to facilitate the work, saw pits were dug deep enough for one man to stand upright in. The log was placed over the pit so that one had to pull from above and the other from below. The latter, who was in the more unpleasant position, was supposedly called the „underdog“ in the process.

Frame saw with sawhorse – for sawing the log into boards or beams:

One carpenter stands on the log and pulls the saw up empty. The second and third carpenters stand on the ground and do the actual sawing.

Illustrations: left saw 19th c. sawhorse 1991 (Handwerksmuseum Deggendorf), right Trummsäge in the Carriage Museum Großraming.

Water wheel

The water wheel is the oldest engine used by man. It was already known 2000 years ago in the states of classical antiquity. The water wheel did not gain any economic importance for powering tools. It was not until the beginning of the 13th century that technology had advanced to the point where the waterwheel could also be used as a source of power in the production of sawn timber.

First sawing machines

The very first signs of the production of sawn timber with machine tools date back to the first half of the 13th century. The oldest surviving depiction of a sawing machine shows a water-powered reciprocating saw, which was called a sawmill.

The drive mechanism took the flow energy offered by the flowing water and, transforming the rotary motion into rectilinear movements, transferred it to the saw frame and the pushing tool.

From then on, for more than 600 years, until it was replaced by the steam engine, it was to remain the most essential power engine in sawmills. With the exception of areas where wind power was used. In the Pram Valley, however, wind power was used only for the operation of wells.

Cam or knocking gate

To convert the the waterwheel’s shaft rotary motion into the saw frame’s stroke motion, firstly the cam drive was used. The cams were mounted directly on the extended shaft.

Oldest surviving depiction of a sawing machine – created around 1230 by Villard de Honnecourt with the legend: „This is how you make a saw, to saw by itself.“ It is a cam gate.

The saw blade is attached at one end to the scissor-like lever device anchored in the ground and at the other to a flexible spruce rod. It moves up and down. Cams are attached in a cross shape to the horizontally arranged corrugated tree (the number of cams depended on the water supply). They alternately press down the saw via the lever, which in the process makes the cut and at the same time stretches the spruce pole, which can be up to 8 m long. Each time after lifting a cam from the lever, the spruce bar pulls the saw blade up again. The wheel mounted on the corrugated beam between the mill wheel and the cam cross engages the log from below with its teeth and continuously pushes it between guides against the saw blade.

Sawmills in Pramtal since 13th century

For 1312, a sawmill is allegedly documented for Upper Austria, but we could not verify this. What is certain, however, is that the Furthmühle in Pram looks back on a history of around 650 years, and today it is the only one of the former 43 mills along the entire course of the Pram to have survived. In the „Schaunberger Urbar“, a list of the income of the Earls of Schaunberg from 1371, the Furthmühle is mentioned for the first time as follows: „Pram, mul und sag, furtmul zu Pram“.

It is highly probable that until the middle of the 15th century all sawmills had creels with cam drive. These were replaced by the Venetian frame in Central Europe.

Source: Exibition Handwerksmuseum Deggendorf.
Historische Bilder und Texte VEB Fachbuchverlag Leipzig „Vom Steinbeil zum Sägegatter“ Finsterbusch/Thiele