SEAMS Projects

Tangye Gas Engine Revival at Cobbs Mill Hurstpierpoint West Sussex

In over ten years of involvement in the restoration of stationary engines and related equipment, SEAMS members have amassed a significant amount of experience. We were therefore well pleased when asked to take on a project to return the large Tangye producer gas engine to working order. The owner has dedicated himself to restoring the mill which had fallen in to decay having been standing idle and largely untouched since the 1960’s. This task is now largely complete but the restoration of the engine and gas plant, still in its original location, was a task that he felt was best attempted by a group like SEAMS.


The Mill

First recorded mention of a mill on the site was in the Hickstead Estate records for 1605 referring to the division of land ‘abutting a brook running from Cobb’s Mill to Herrings Bridge on the north east of the lands of Thomas Avery’. Land tax records indicate that John Lindfield owned Cobb’s Mill in 1780. The leasehold passed to Nathaniel Avery (by 1785) and then Thomas Avery (1786) before reverting to William Lindfield by 1808. A Henry Pickett is named as the leaseholder in 1809. By the end of the Napoleonic wars, Cobbs Mill was owned by Anthony Ede of Shermanbury but passed to his son Thomas Ede by the time the leasehold was again offered for sale in 1834 and taken up by Henry Pickett. The property was then let to Charles Packham when the previous tenant James Mitchell had departed for Duncton postmill at Clayton. In 1865, the property was being offered for sale by the trustees of the Late Mr Edward Pickett, Henry Pickett’s son. The sale notice records the mill to have been a brick and timber built structure driving four pairs of stones and stood upon a stream with a fine supply of water. The tenant was Charles Packham, likely the son of the ‘Charles Packham’ who had been active in 1834. An article in Sussex Country Life published in 1947 claims the brothers Charles and Benjamin Packham were working in 1850 and that Benjamin and his nephew Charles Packham worked from 1875 until 1881 when Benjamin left for Leigh Mill in Cuckfield. Charles Packham then ran Cobbs Mill alone from 1881 until his death in 1912 being succeeded first by his widow and then Charles Packham Ltd.

The mill machinery survives largely intact and is mostly Victorian. This must have been a substitution for the original machinery. The Mill is now a mixture of dates and styles ranging from a small part of the east wall of the tile hung cottage believed to have late mediaeval original to the 17th century tile hung wood framing of the millers cottage , the 19th century elevations of the mill itself and the imposing brickwork of the mansion added to the north in 1877.

The Engine

The engine is a Tangye producer gas engine number 12330 believed to have been installed circa 1910. The engine and producer gas plant, number 5549 and built by the National Gas Engine Co at Ashton Under Lyne, are thought to have been second hand when supplied by W Holloway and Sons, Engineers of Shoreham Sussex. It is quite possible that previous duties involved electricity generation because of the two heavy duty flywheels for steady running. There were also many ‘used’ spare parts surviving, possibly from sister engine/s. Anecdotal evidence of a mishap still lives in memory. It is reported that one day, whilst the normal engineer was absent, an attempt was made to start the engine using the mill overshot water wheel to drive it over. This resulted in the engine firing at the wrong point in the cycle and irreparable damage to one of the flywheels. To this day one flywheel is clearly a replacement being smaller (66″) than the other (72″) and carrying the serial number of a much earlier Tangye engine number 5112 and marked “Tangye and Bailey Patents Process”. The engine bore is 13″ and believed to be the K size from the X type range of Tangye range produced up to and including 22″ bores.


It was back in late 2004 that a group of SEAMS members started work cleaning and repairing with a view to getting the engine running. The National Producer gas plant (installed second hand with the engine but not considered safe to ever run again) was cleaned and painted. A major job was removing the 14″ diameter piston and connecting rod to free off rings stuck after many years of hibernation. Main bearing caps were removed to check, scrape the bearings and clean the oil ways. Many parts were stripped out, cleaned and any significant wear rectified before replacement and the three main valves were removed and ground in. Other tasks included rigging a water cooling system as the original pumped system was deemed unsuitable and could not be protected by antifreeze. The alignment of the crank was checked since subsidence of the outrigger bearing outboard of the main drive pulley was likely. Only a small adjustment was required to this bearing.