Products

Enclosed Motor-Gearbox units

A range of high-quality, compact and convenient axle-hung motor-gearbox units, running in ballraces and with enclosed two-stage spur gears. These units offer easy fitting and dirt-excluding performance, and are mainly intended for outside-frame applications such as bogies having free space between the wheels. Each unit is run in to ease up any tight spots, and then it’s performance measured for speed and current draw. Comprehensive instructions are included along with a test certificate.

Inclusion of an axle is optional for the Gauge 3 units, but axles are supplied with the smaller Gauge 1 units. Two types are offered for Gauge 3; the LP SLIM and HP. These are superficially similar, and are small enough to fit in pairs (motors adjacent) into bogies down to a 7’ wheelbase. Single units, or pairs with one motor facing outwards, may fit into smaller bogies. Smaller units are the Type S1 and S2. Whilst their principal use will be for Gauge 1 or other 45mm gauge garden railways, they can be used for slower moving and low powered Gauge 3 locomotives or trams, as the compact dimensions permit freedom to use smaller wheels or internal frames if desired.

LP SLIM

The LP SLIM gearbox unit is universally suitable for most bogie applications in Gauge 3. Whilst a single unit will pull two lightweight cars of a multiple unit, several units can be used for higher powered applications or to improve traction. It is often difficult to get the power down without slip when just one axle of a Bo-Bo bogie is powered, and so use in pairs is often a good solution. When fitted to each powered axle of a mainline mixed-traffic diesel such as the Class 25, considerable tractive effort results and a scale speed of over 80mph. Requires 12-15v.

The gear ratio is 10:1, and a 1/4” axle is required for 63.5 mm gauge track. Typical scale speeds achieved will depend upon the driving wheel size, the number of cars/coaches, and the number of motor-gearbox units fitted in the train. A performance based on a given wheel size and voltage is given below, and is based on the author’s tests, but it is stressed that every application will be different. Free running wheel revs at 12v ~ 700 rpm. Under load current draw typically 200 -300mA each. Scale speed with two units in a 2-car train at 12v and 3’ driving wheels ~ 70-75 mph. Drawbar pull with two units in a locomotive of weight 4.9kg at 12v and 3’ driving wheels ~1kg. Drawbar pull with four units in a locomotive of weight 5.8kg at 12v and 3’9” drivers ~ up to 2.4kg. Minimum wheel size 2’ 9” diameter (37mm in Gauge 3). Options are for the key hole to be placed upper or lower with reference to the sketch. The LP SLIM has been designed to be as narrow as possible, given the size of the motor. This gives a little more scope for fitting within internal frames, but ingenuity will still be required as the space will be very tight! My Power Bogies use the LP SLIM gearbox unit and have functional inside frames, with the outer frames being cosmetic dummies. The LP SLIM unit is offered either alone or as part of a kit to assemble a powered bogie for several versions of railcar, DMU or diesel-electric loco.

HP

The HP motor-gearbox is intended for mainline express diesels and electrics that use outside framed bogies, but can also be used in the tenders of steam outline, and other higher-powered applications. A supply voltage of up to 18V can be used, but experience has shown a very good performance when using a 12V sealed lead-acid battery. Scale speeds of over 100mph are possible. It uses all-metal gears of 14.2:1 ratio and a high quality 5-pole motor.

Axles required are for 63.5 mm gauge track, and the unit can be ordered to fit axles of either 6.35mm (1/4”) or 8mm diameter. As for the LP SLIM, the key hole can be placed at top or bottom. Pictured in the Gallery is a “Peak” bogie In Gauge 3 showing that three units can be fitted easily. This loco has very good performance with three driving axles on a 12V supply. The rounded nose of the gearbox is located in a slot in the frame stretchers, allowing sliding of the middle drive axle as required for curves. Typical performance of the HP unit is given below for guidance, but it is stressed that every application will be different. Free running wheel revs at 18V = 1200 rpm. Under load current draw <2A. Scale speed with three units in a locomotive pulling nine Mk1 bogie coaches: using 18V and 3’ 9” driving wheels ~ 100 mph + using 12V and 3’ 9” driving wheels ~ 65 mph

Type S2

Replacing the S1 and externally identical but with internal improvements. The S2 gearbox is a unit of moderate power, designed for the smaller spaces between the wheels and smaller power requirements of industrial narrow gauge (eg G45), or shunters and goods locos in Gauge 1 or Gauge 3. Trams or rail buses are another ideal application for either G3 or G1. If used in Gauge 3 then either inside or outside frames can be used, but for 45 mm track it will mainly be suitable for outside frames unless the special gearbox mounting bracket is used.

There is potential to fit within inside frames in Gauge 1 but some careful design with cutaways in the frame may be required. More dimensional information available on request. It will not fit between the wheels for 32 mm track. Either a 12V, 9V or 5V motor can be specified with the standard gear ratio of 10.8:1. If greater speeds are required then the optional high ratio of 5.4:1 can be specified, but only the 12V motor and use in multiple is recommended. For G1 or G3 track. The unit is not supplied with an axle but the Slaters G1 type suitable for twist-on Slater’s G1 coach or wagon wheels is suitable, and it is recommended that I fit either your own or a supplied axle before delivery. These axles give.40 mm back-to-back, but a modified G3 axle can be supplied as an alternative. Suggested wheel diameters are 28 mm and above; for instance 30 mm represents the common wheel size of 3 feet in Gauge 1. Typical scale speeds and drawbar pull will depend upon the driving wheel size, the weight of the loco and train, the number of motor-gearbox units fitted, the motor rated voltage, and of course the scale in question! Some combinations tested are given below for guidance, but it is stressed that every application will be different. These examples tested all used the gear ratio of 10.8; use of the alternative 5.4 gear ratio will result in lower tractive efforts but higher speeds. Example 1 - 30mm driving wheels, twin 12V units fitted in 2.3 kg loco, towed weight 8kg: Scale speed (G1) approx 45 mph Scale speed (G3, G64 1:22.5) ~ 33 mph. Current draw <130mA each motor. Drawbar pull, max, - approx 1kg with wheels just slipping. Example 2 - 40mm driving wheels, twin 12V units fitted in 2.3 kg loco, towed weight 8kg: Scale speed (G1) approx 60mph, Scale speed (G3, G64 1:22.5) approx 42mph. Current draw ~ 130mA each motor (recommended limit for continuous use). Drawbar pull, max, - approx 0.75kg. Example 3 - 30mm wheels, twin 12V units fitted, pulling a dead loco of 7kg with considerable friction: Creep speed at small throttle opening. Drawbar load, steady, ~ 0.5kg. Current draw to accelerate load ~ 200 - 250mA each motor. Current draw at steady creep speed ~ 100 - 150mA each motor. Current draw when held at buffers with wheels slipping ~ 450 - 500mA each motor (not advised). Free running wheel revs ~ 490 rpm. Whilst the 9V motor can give very similar performance to the above, lighter trains are recommended to prevent continuous current draw exceeding 130mA. The 5v motor should only be used for lightweight applications such as trams.

Bogie Kits

A range of easy assembly kits in G3 for BR prototypes, including powered bogies for diesel locos and DMUs, Mk1 coach bogies, and a USATC wagon bogie. All include wheels, laser cut steel frames and decorative dummy sideframe mouldings or prints. Most have ballraces and sprung suspension to keep the wheels in contact over track irregularities.

Coach Bogie BR1

The original BR1 bogie design of 8’ 6” wheelbase, brought in by British Railways to support the Mark 1 coaches. Many preserved examples of Mk1 coaches still utilise this bogie design. Later experiments by BR developed bogies to support the additional weight of buffet cars, and to provide better ride quality for passengers, and these may be offered later in kit form too. The kit contains all components to build a pair of bogies as shown above.

These bogies will fit the coach kits supplied by Kippo Models. Slater’s disc wheels are supported by ballraces for low-friction running, and springing is included to absorb track undulations. Tiny hex-head bolts are supplied to add realism for the keepers, and the moulded side-frames reproduce the fine detail. The main frames are laser cut and easy to fold into shape. Drills, files, a vice, and normal hand tools will be required for assembly. No soldering is required. Full illustrated build instructions are supplied. Coach bogies of other wheelbases may be possible; always happy to discuss your requirements

DMU Bogie

.The DMU bogie is representative of the 8’ 6” wheelbase bogies used by British Railways for the First Generation Diesel Multiple Units produced in the late 1950’s and early 60’s, such as Classes 108 and 121. The kit can be supplied as one of three options, unpowered as a trailer bogie; single motor-gearbox power unit; or twin motor-gearbox power units. The powered versions use the LP SLIM enclosed motor- gearbox power units, which are designed for 12V-15V supply. The kit contains all components to build one bogie as shown above. In addition, a moulded representation of the secondary springing may be available at a later date. These bogies will fit the Class 108 kits under development by Kippo Models. Slater’s 3’ disc wheels are supported by ballraces for low-friction running, and springing is included to absorb track undulations. Moulded dummy side-frames reproduce the fine detail. The main frames are laser cut and easy to fold into shape. Files, a vice, spring clamps and normal hand tools will be required for assembly. Fully illustrated build instructions are supplied.

Typical uses are for the Class 108, which was in either 2, 3 or 4-car units. It is suggested that the number of LP SLIM power units matches the number of cars, and so typical builds could be as follows: 2-car: twin-powered bogie plus 3 x unpowered trailer bogies 3-car: twin-powered bogie plus single-power bogie plus 4 x unpowered trailer bogies. When powered as above, realistic scale speeds of 65-75 mph should be readily achievable if using a 12V supply. Whilst fewer numbers of power units will certainly work well and accelerate the DMU from rest, lower top speeds may result. This may be perfectly adequate for a compact railway, but as a minimum it is recommended that the number of power units is half of the number of cars. This means that a 2-car train will run with one power unit, but a 3 or 4-car train will need two power units as a minimum.

Class 25 Diesel Bogie

These bogies have been developed for the locomotive in production by ALD Models. To provide a realistic performance in the model, all axles are powered as per the prototype. The wheelbase is 8’ 6”, wheels are 3’9” turned from solid steel and axles are sprung-compensated.

The detailed resin-printed dummy sides are produced by ALD Models as part of their body kit, or can be provided with the bogie kit at extra cost. In common with all my other power bogies, full use of ballraces is made for smoothness and longevity. The bogie pivot arrangement is a robust 12 mm diameter hollow spindle designed to turn in a body-mounted brass bush (supplied) with power wires passing up through the pivot.

Class 20 Diesel Bogie

These have been developed for a potential body kit planned by Kippo Models. The bogies are very similar to the DMU bogie described earlier but use the larger Slater’s wheels of 3’7” and of course the appropriate detailed sideframes for this class which are included.

Dummy leaf spring secondary suspension (not shown) is now included in the kit. With wheels being insulated the possibility of live rail pick up is optional and provision is made in the chassis for optional GRS spring plungers to the wheel rims. The bogie pivot is the same robust hollow-spindle assembly as used on the Class 25. The use of motor-gearboxes is optional so the bogie can be ordered as trailing or powered.

USATC Wagon Bogie

This US Army Transport Corps wagon bogie (or ‘truck’ in US parlance), of the Bettendorf style, represents the myriad of uses in the first half of the C20th, culminating in large scale imports into Europe and the UK during and after the Second World War. In military use it was used for many types of flat bed or closed wagons, and for the tenders of S160 steam locomotives. The kit includes all items to build one bogie as pictured, and is a simple fold-up design in steel, supplied with full build instructions. The disc wheels scale at 3’ diameter.

No springing is used as the wheelbase is very short at 5’ 6” and a small amount of looseness at the pivot bolt (supplied) allows the necessary bogie pitch over track undulations. A laser-cut steel backbone is used to support the axle bushes, and the sideframes are non-structural, printed in PLA. These sideframes will require some finishing operations, to taste. Files, spring clamps and normal hand tools will be required for assembly. No soldering is required. Full illustrated build instructions are supplied.

45mm Accessories

These matched brackets enable the S1 or S2 gearbox to be mounted from the underside of a flat vehicle floor, without the need for any further support of the axle. This may suit lightweight 45mm gauge models, including trams. The axle ends can be removed to allow your own dummy outside frames to be used. The axle bracket and gearbox bracket are available separately, and each have four holes for attachment to the floor.

Each bracket positions the axle centre at 21mm below the floor. Wheels of up to around 35mm tyre diameter are readily suitable, or larger wheels if suitable cutaways are made in the vehicle floor. Fittings are provided with each to allow a standard Slaters 3/16” G1 axle to be supported, or for the S1/S2 gearbox units to be attached. Minimum axle spacing 48mm. Printed in tough PLA+

S2 Gearbox unit

The S2 is identical in most respects to the S1, but importantly allows use of a standard 3/16” dia axle, such as the Slaters G1 types. The price includes for the user’s axle to be fitted before leaving the ATR works. All performance details identical to the S1.