Live Steam 
Quad Cylinder "Mill" Model Steam Engine 
Fully Machined Kit in Brass, Bronze and Steel 


The horizontal four or quad cylinder "mill" engine is two twin cylinder mill engines connected via a large fly wheel on a steel plate and inlet manifolds, tee and elbow connectors.

As such it is still relatively simple and retains the basic mechanics of engines which powered mills and workshops and which needed the extra power provided by a quad cylinder engine.

NOTE: Pictures are of the assembled kit, this listing is for the kit of parts, not painted or polished, see picture.

The classic mill engine layout has four double acting cylinders, eccentric driven slide valves and the large brass flywheel offers smooth running and is capable of powering a range of accessories, in a variety of roles. The engine also includes 2 x triple split bronze pedestal bearings for the crank shafts, tube sliders and very substantial cast bases.

On the twin crank shafts, the cranks for each cylinder are offset by 90° which means the engine will self-start in any position.

The engine will run in reverse by applying the steam (or air) input to the outlet ports.

The kit consists of precision produced parts each carefully made and checked to ensure ease of assembly and reliability in service.

The cylinder assembly and piston are manufactured from brass and the piston shaft, connecting rods, column screws and valves from stainless steel so are not susceptible to the corrosion. The piston shafts passes through an adjustable glands and the steam inlet can be on the top or bottom of the chests, left or right hand sides.

Detail Specification:
- Type: Tube Slider
- Bore: 14mm
- Stroke: 18mm
- Flywheel Diameter: 70mm
- Valve type: Piston
- Height (excluding manifold): 75mm
- Length: 150mm
- Width: 196 mm
- Weight: 3.3Kg
- Connections: 1/4" x 40 tpi ME

The kit consists of a set of fully machined parts that can easily be assembled using simple tools such as a screw driver, allen keys, pliers and metal file. The parts are mainly unfinished metal and will also require painting, polishing, filing, etc. to achieve the appearance shown in the pictures.

NOTE: The kit is supplied with slot head screws but socket head screws (as per the pictures) and hex head screws are available as options. Some screws as provided may need to the cut or filed to length to complete the model.

When assembled the engine is fully working and can be run using steam or simply using compressed air e.g. from hand or foot pumps.

To power the engine with live steam, connect it to one of our Model Steam Boilers.

Horizontal Mill Quad Cylinder Engine Kit

  • Product Code: HQA
  • Availability: 3
  • £515.00


Available Options


Related Products

Pulley Wheel

Pulley Wheel

The pulley wheel is designed as a simple add-on to all our engines and can be used to drive all kind..

£6.00

4mm Socket Spanner/Spinner for M2

4mm Socket Spanner/Spinner for M2

4mm Socket Spanner for use with M2 hex head screws/nuts.Very useful for assembling our model steam e..

£4.00

5.5mm Socket Spanner/Spinner for M3

5.5mm Socket Spanner/Spinner for M3

5.5mm Socket Spanner for use with M3 hex head screws/nuts.Very useful for assembling our model steam..

£4.00

4mm 5.5mm Spanner for M2 and M3

4mm 5.5mm Spanner for M2 and M3

NOTE: Now included with all our engine kits.Small stamped steel spanner for use with M2 and M3 hex h..

£1.00

Steam Reversing Throttle Valve

Steam Reversing Throttle Valve

The valve will allow our engines  to be run in forward and reverse and their speed controlled b..

£39.00

Tags: Live Steam, Model Steam Engine, Fully Machined Kit, Twin Cylinder Mill Engine