Live Steam  
Bitsa Twin 2 Cylinder Steeple Model Steam Engine 
Fully Machined Kit in Brass, Bronze & Steel 

"Bitsa" - bits of this, bits of that. We have a few parts which are surplus or not quite useable but are too good to just throw away, hence the Bitsa Twin Engine kit.

The Steeple or Entablature engine is basically two upside down Marine Single Engines with 4 Columns and Flywheel from our Beam Engine, mounted on top of a base platform.

The engine kit will of course work as supplied but is one of our more challenging. So customers can improve by, adjusting fits (e.g. filing), filling redundant holes, etc., as per preferences.

The kit can also be customised, for example supplied with a flywheel from one of our other engines, pulley wheel(s), inlet manifold, hex/slot screws, etc. - let us know your ideas.

The Bitsa engine is a simple design, yet retains the basic mechanics of engines which powered boats, farm equipment, and workshops in the nineteenth century.

NOTE: The holes on the Column bases are not used as they are out of position (hence not usable on the Beam Engine) and the Beam Flywheels may have a very slight wobble.

NOTE: Pictures are of the assembled model (not painted or polished) - this listing is for the kit of machined parts.

The Bitsa engine layout has two double acting cylinders, eccentric driven slide valves and the large steel flywheel offers smooth running and is capable of powering a range of accessories, in a variety of roles. The engine also includes 2 sets of double split bronze pedestal bearings for the crank shaft, tube sliders and a substantial steel plate base.

On the twin crank shaft, 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. Our Reversing/Throttle Valve (optional extra) will control the direction and speed of the engine in either direction.

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 rod, column screws and valve from stainless steel so are not susceptible to the corrosion. The piston shaft passes through an adjustable gland and the steam inlet can be on the front or back of the chests.

Detail Specification:
- Type: Tube Slider
- Bore: 14mm
- Stroke: 18mm
- Flywheel Diameter: 120mm
- Valve type: Piston
- Height: 234mm
- Length: 160mm
- Width: 118 mm
- Weight: 3.4Kg
- Chest 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 holes on the Column bases are not used as they are out of position (hence not usable on the Beam Engine),  and the Beam Flywheels may have a very slight wobble.

NOTE: The kit is supplied with socket or hex head set screws (as per the pictures), although some screws for ease of installation, have to be socket head screws. Some screws as provided may need to the cut or filed to length to complete the model, contact us if this will cause a problem.

Other options also available including a Manifold set which combines the two inlet ports together into a single port.

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.

NOTE: The model steam engines and boilers are NOT children’s toys and should not be assembled or operated by children unless under close supervision of an adult.

Bitsa Twin Cylinder Engine Kit

  • Product Code: BVTA
  • Availability: 1
  • £415.00

Available Options

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