Priestman excavator conservation – April-May 2019

The Priestman Ditcher Model No. 1 is one of the first things that visitors see outside Streetlife Museum. If you have come to the museum since April 2019, you may have noticed that it was recently conserved, which was made possible thanks to visitor’s donations.

The Ditcher Model No. 1 was made in 1921. It was a prototype, a forerunner of modern excavators and the first of its kind.

The Ditcher before conservation

After World War One, food shortages made field drainage a priority. Proper irrigation and drainage were urgently needed in order to make millions of acres of water-logged land suitable to grow crops. Previous drainage methods relied mainly on manual labour, an expensive and time-consuming process. The government asked Hull company Priestman Brothers, founded by William D. Priestman, to produce a machine for this work and in 1921 they developed the Field Ditcher, a land excavator.

The main components of the Priestman Ditcher No.1

It was towed by a tractor, which also powered the winch. Previous excavators had had to travel along railway lines, which meant that their movement was restricted.

Publicity picture of the Priestman Ditcher Model No 1 powered by a Clayton 35hp tractor, c. 1921. Source Priestman Archive, Bill Bromwich.

The prototype machine was built within 12 weeks. In 1921, at drainage trials in Lincolnshire, government officials, farmers and other interested parties had a chance to observe the machine in action. It was received positively and a special award was given to the company by the Ministry of Agriculture and Fisheries for the Field Ditcher’s innovative new design.

This isn’t the only time that conservation work has been done on the Ditcher. In 1961-62 the machine was found in poor condition in a field in Lincolnshire. Priestman Brothers purchased it for scrap value and brought it back to Hull for restoration, carried out by the company’s Apprentice Training School.

 

From left to right: Kevin Spoose; David Borman (Chief Apprentice); an unknown apprentice; Jeff Foster; Ian Davison; Ian Ingles; Les Sharpluss (Training Officer); Tony Lawrence; Joe Rae; Ken Parker. This photgraph was taken in 1962/3 at the back of the training school on Priestman land (Hedon Road)

Despite the poor condition of the machine, a considerable number of missing parts and lack of detailed drawings, the Ditcher was restored over a period of 18 months and the involvement of 30 apprentices. The restoration included cleaning and painting of historic parts, drawing and manufacturing of replacement parts, especially missing gears and shafts. Eventually, shafts new and old were refitted, keys made and bedded, gears, brake straps, ropes, chains, drums and jib were fitted and tested. The paintwork featured new parts painted in black and historic parts in red. The machine was fitted with a cranking handle to operate the drive shaft for demonstration purposes.

Although a considerable amount of restoration work with the use of new material was carried out during this time, the original design was preserved with minimal additions or improvements.

Furthermore, the functionality of the machine was retained making it possible to demonstrate its function for educational or training purposes.

The Ditcher being delivered to Streetlife Museum, November 1990. Photo taken by Bill Bromwich.

After 1963 the machine was preserved at the Priestman Offices in Hedon road before it was purchased by the Museum in 1990.

In April 2019, conservation work began on this important piece of industrial history.

Among many other aspects, the corroded areas were treated, dirt was removed, and the whole structure was sanded and repainted. 

The Ditcher during conservation, being jet washed.

Before and after the removal of corrosion and repainting of slew gear.

Removing corrosion products from the chequer plate.

Applying the top coat of paint.

Retouching the Priestman sign.

The Priestman Ditcher Model No.1 is now nearly 100 years old. The conservation work done has protected the Ditcher for many years to come so that it can continue to illustrate the ingenuity and innovation of a local family firm that developed a world renowned line of industrial equipment.

The Ditcher after conservation, May 2019.