Stone Lifter - Wooden Axles - A Study In Craftsmanship

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For centuries, axles were made from wood.  Eventually, mass produced steel axles eliminated the need for wooden axles. What was also eliminated was the craftsmanship of the carriage maker. These artisans were experts at shaping the hub ends of axles to receive a wheel. They were celebrated for the tools they made to do this.

Stone Lifter - Wooden Axles and Lynch Pin Assemblies

The axles of the stone lifter are a testament to fine craftsmanship. The ends of the axle, or hubs, had to be perfectly formed to accept the wheels. It was essential that the wheels turned properly on the hubs.

Since the inside of the wheels were tapered, the hubs had to be tapered as well. This made the hubs weaker at the end. A key slotted through a key-way in the end of the hubs was used to lock the mounted wheels in place. The key-way weakened the end of the hubs further. The solution was to fit a steel lynch pin assemblies to the hubs.

To avoid interfering with the turning of the wheel, the lynch pin assemblies had to be recessed into the hubs. The lynch pin assemblies extended beyond the hubs into the axles proper. Bolted in place, with a bolt that ran completely through the axles, the lynch pin assemblies were well secured. Steel collars, around the base of the hubs, served to hold the assemblies in place. With the steel lynch pin assemblies there was less stress on the ends of the hubs.

The lynch pin assemblies made removing a wheel very easy. Remove the key from the key-way and slide the wheel off. And those wheels had to be taken off regularly in order to grease the hubs and insides of the wheels. The squeaky wheel really did get the grease.

  

Stone Lifter – The Front Axle

Stone Lifter - Front Axle

From the above illustration, you can see that the front wheels of the stone lifter were set close together. This was advantageous for making sharp turns, such as those required to get the stone lifter in position over a stone fence. The stone lifter was designed to just that.

The above rendering also illustrates how the front axle pivoted around the frame of the stone lifter by means of a simple steel post. A simple but effective technology.

Images prepared from a digital 3D model of an actual stone lifter. Modelling was in Amapi. Bryce rendered the images. Post production was in Adobe Photoshop. The interactive graphic was prepared in Adobe Flash.

Stone Lifter - An Appropriate Technology

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Stone fences, paralleling country roads, record the passage of the stone lifter. Pattern books guided local craftsmen in their construction. This was especially true in frontier areas where the need was greatest. Industrial advances gave rise to modern factories, which also turned out stone lifters. One manufacturer promoted their design as being capable of lifting a 5 ton boulder.

Stone Lifter – Employing Mechanical Advantage

Stone Lifter - Lifting Mechanism

The above illustration isolates the stone lifting mechanism. A steel axle traversed the wooden frame from side to side. Hooks suspended from attached chains secured the stones. The wooden wheel attached at one end of the axle provided the lift. In this example, the hardwood wheel had wooden teeth bolted to either side of the wheel forming a V-shaped groove. A length of rope nestled in the groove was wound around the wheel. When pulled it turned the wheel and raised the stone. This was a practical application of the principle of mechanical advantage. Larger wheels produced greater mechanical advantage.

For smaller stones, of a few hundred pounds, manpower was sufficient to get the job done. For larger boulders, draft animals were used to pull the rope. The larger boulders only had to be lifted enough to clear the ground. They were used to form the foundation of the stone fence. The smaller stones would be lifted higher to clear existing levels of construction.

Stone Lifter – Locking Mechanism

Stone Lifter - Locking Mechanism

With the stone suspended above the ground, the problem became how to keep it there. The locking mechanism, illustrated above, provide the solution. A sliding wooden beam was moved across the frame to engage the wooden teeth on the lifting wheel. This was accomplished by shifting a lever, that pivoted on a few metal parts fabricated by a local blacksmith. This arrangement eliminated the need for a metal ratcheting system.

With the suspended stone locked in place, the stone lifter could be manoeuvred over a fence to a desired location. After opening the locking mechanism, the stone was lowered into place.

Why This Technology Was Appropriate

Wood was plentiful and available locally. Metal had to be transported often a great distance and at great cost. Using hardwoods minimized the need for metal. The owner of the stone lifter could make many repairs to the wooden components, such as the teeth on the wheel. This technology was also appropriate to working with horses. They applied steady pressure, with no surges in power. Their strength was also appropriate to a machine made largely of wood.

Images prepared from a digital 3D model of an actual stone lifter. Modelling was in Amapi. Bryce rendered the images. Post production was in Adobe Photoshop. The interactive graphic was prepared in Adobe Flash.

 

Using 3D Graphics to Record and Interpret Artifacts

Stone Lifter - Creating a 3D Model From an Artifact

Stone Lifter

The stone lifter, shown above, was modelled from a real artifact. However, it was in a poor state of repair. Some remediation had been attempted. But rot had gotten into the wooden axles where the wheels were mounted. The artifact was not only in poor condition, but some parts had been removed and left nearby. So creating a 3D model of the stone lifter involved an element of conservation as well as documentation. Interpretation was also involved.

The stone lifter was photographed and line drawings prepared from the photographs. Then measurements were made of the actual artifact and entered on the drawings. These measured drawings were used to create a digital 3D model of the stone lifter in Amapi. The 3D model was imported into Bryce and rendered. The rendering was cleaned up in Adobe Photoshop.

The ability to remove obstructing parts to get a clear view of things is a real advantage to using 3D graphics software. Animating a digital artifact provides insight into how it operated or was used.

Of course the process described above was not so linear. It was far more iterative, with many return visits to the artifact. Not only did this fill in valuable details, but it provided insight into how the stone lifter was constructed.

Segwun - Creating a Digital 3D Model From Plans

Steamship Segwun - Final Version - From 1948 to the Present

In the case of the steamship Segwun, you have an artifact as well as a complete set of plans. These drawings were completed by a naval architect during the late 1970s in the restoration of the Segwun. These drawings represent the final version of the Segwun from 1948 to the present. However, in the last 125 years, the Segwun has gone through many changes. The above rendering of the profile of the port side of the Segwun represents an accurate representation. But what if you wanted to create a profile of the Segwun in 1887 when she was first launched into Lake Muskoka as the Nipissing II?

Nipissing II  - Using Historic Photographs in Interpretation

Nipissing II - Launched 1887 at Gravenhurst - Conceptual Rendering

There are photographs of the Nipissing II. However, some are not very clear, while others show obvious distortion. The iron hull, at least up to the main deck, and the decks themselves are a constant. However, in almost all other respects, the two ships were very different.

A photograph of the Nipissing II, circa 1888, was used to create overlays that were place over the Segwun graphic. Adobe Photoshop and Illustrator were used to do this. The rendering shown above can not be considered 100% accurate. It is a conceptual rendering based on the best evidence available. The gold standard would be a rendering made from a digital 3D model, created from the actual plans from that period. Unfortunately, you have to work with what you have.