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Dear STICK Friends,

STICK will attempt to send out entertaining and informative items on various subjects of interest to our network. We will also be using social media such as Twitter to keep in touch.

Today, we we look at two stationary steam engine projects currently underway and free online events at the Devil’s Porridge Museum.

Garlogie Beam Engine, Dunecht, Aberdeenshire

Image: Elevation drawing of Garlogie Beam Engine,1980. Copyright: Historic Environment Scotland

At the end of September 2019, the Garlogie Beam Engine Trust, a registered charity in Scotland (SC049632), was set up. This is the critical first step towards opening the site and restoring the beam engine and power turbine. For more information, see the Trust website here. There are also regular Facebook updates here.

The planned September 2020 Doors Open Day event could not be held due to the Covid epidemic but a short YouTube video has been recorded of the site for those wish to see the beam engine and turbine.

Garlogie Beam Engine to the rear of Garlogie Village Hall is on the B9119, 10 miles west of Aberdeen. Believed to have been built between 1830 and 1840 - possibly by Mitchell and Neilson of Glasgow - it is the only rotative beam engine remaining in situ in Scotland. It drove Hadden’s wool spinning mill until 1904. The mill itself was demolished in 1934 but the engine house and its engine survived remarkably complete - it avoided the McNaught compounding process visited upon such single cylinder engines of this period. An adjoining hydro-electric power plant was built in 1923 for the Dunecht Estate (Swiss-made horizontal shaft Francis Turbine with English Electric Company generator, earlier vertical shaft turbine pit, surge shaft in a mound, a dam and company housing).

The beam engine was refurbished and reopened in 1992 and later managed by Aberdeenshire Council Museums Service.

Balloch Patent Slipway Carriage technical news

Image: copyright JS Mitchell, 2020

The new slipway carriage at the The Maid of the Loch’s Balloch Slipway will form part of the steam-powered winch house and underwater railway infrastructure. The patent slipway is on three rails with a double centre rail enclosing a rack for locking the carriage on a 1:18 gradient. The outer rail centres are 5.79m and the new carriage replaces two previous timber iterations, the first being in 1901. It is believed that this is the only remaining working steam slipway in the world.

The new 50 tonne carriage is in steel but with structural timber elements on the outrigger chassis amounting to 5 tonnes of (sustainably certified) opepe, a West African hardwood. The original 80 cast iron bogies, running on 240 cast iron wheels, have been reincorporated, along with the riveted outrigger arms, silt ploughs and tow bracket. The all-up weight of the carriage and ship, the “Maid of the Loch” will be c.600 tonnes and the pull required from the steam winch will be 100 tonnes at 1 metre per minute; the speed being limited by the boiler capacity.

The carriage design had to stay within the 50 tonne weight limit requirements, be able to bear the weight of the 550-tonne ship and the tension load of 100 tonnes. It also had to comply with requirements of appearance and working principles, which have been achieved by using solid timber outboard lower chassis and the original running gear. Lightness is achieved by using longitudinal universal columns (H beams) to form the correct visual ‘mass’ but being internally hollow. The 51m carriage is made up of five coupled articulating units which can follow height variations on the track while keeping all the bogies in contact.

Inter-chassis stiffening is vital, so light weight diagonal stiffeners, held by single steel pins to allow flexing are repeated the full length of the structure and 90 degree cross brace are included to prevent the structure ‘lozenging.’ All of this has followed the principle of strength with controlled flexibility, weight suppression and of course, appearance.

JS Mitchell ACR FIESiS, Conservation Engineer on PS "Maid of the Loch" and Balloch Steam Slipway

December 2020

Devil’s Porridge Museum, Eastriggs near Annan - Free Online Talks

Devil’s Porridge Museum’s lively and varied programme of talks and events have moved online. Tickets can be booked here.