16mm Projects

Tony Wright's Hudswell Clarke Projects

In an earlier article called 'A tale of two chassis' I described the building of two very different Hudswell Clarke diesels locos and my solutions for the chassis. Well, the project has moved on and the two locos are now complete.

Firstly, let's look at the smaller of the two, Greymouth, which is based on a batch of Hudswell Clarke rail tractors supplied to New Zealand. This build used an Alan Doherty Worsley Works scratch-aid body etch.

Due to the small size of the loco I decided to have the drive in the chassis all below footboard level leaving the bonnet for the batteries. The loco was to be manual and simple. The drive utilised two small focus puller gearhead motors driving two Slaters crossed helical gearboxes. However, I had major problems getting the motors to drive correctly without fighting each other. Disheartened the project was mothballed. Then a couple of things happen. I discovered how good Delrin chain drives were after I'd dismissed them as impractica and secondly in SMT there was an article on using LED light controllers as basic radio control. Reinvigorated, a Googled website found a supplier of Delrin chain and sprocket and a furtle in the bits box turned up a COMO Drills gearhead motor. We were back on.

A mounting was soldered to the gearbox torque arms and drilled to mount the Como motor. The sprockets I ordered came bored to fit the motor and gearboxes, so no machining. These are a tight push fit onto the shafts. A length of chain was made up and a quick test proved all okay. Next an inverted U-shaped bracket was made and bolted to the chassis sides and onto this were mounted the batteries and LED controller using self-adhesive Velcro. All this easily fitted into the body. Off/on switch and a forward/reverse switches were mounted on the chassis sides. This design meant all the gubbins was on the chassis and the body can quickly be removed with two bolts.

The photo shows the batteries, LED controller and fuse on the U-shaped bracket with the COMO motor below. Tests revealed the reception was indifferent so an aerial extension was added and looped into the cab. Range is now well over 12 metres. This lead is the red one in the photo.

This photo of the underside shows the two Slater's gearboxes and the Delrin chains drive.

A photo of the prototype was found on the internet, this showed the one of the locos as rebuilt, plinthed in New Zealand. The body was built as designed, however a cock-up meant I had to mount the open door on the opposite side to the one in the photo. Brass sections were soldered in to stiffen the body and the footboard valances. The prominent external radiator was a feature not well executed in the Worsley works etch and was therefore ditched. The two headers were filed from solid brass, the tubes were made by wrapping fine mesh round brass tube and soldering at the rear. The whole was soldered up using flat sheet and rivets to form the header flanges. As the cab is open it has a detailed interior. I didn't have a photo of the interior so it is based on similar loco shown in Ron Redman’s book, " The Railway Foundry - The Diesel Era. "

The livery is simple as befits a humble shunter. After cleaning by scrubbing with "Barkeepers Friend" and keyed with sandpaper the body was etch primed and finished with house livery; Halford's "Brooklands green." Hudswell maker's plates from MDC were added. Still awaiting delivery is the distinctive Hudswell radiator plate from Narrow Planet.

The two photos show the completed loco. Besides the radiator, added details (not in the Worsley Works etch ) include the typical Hudswell exhaust chimney, the hand starting gear on the front running board, the dummy axle boxes and chain adjuster and coupling to suit my needs.

ETHYL, the second chassis worked well as designed, although the final crossed helical gears drive is one to one ratio, with hindsight I wish I'd put in a reduction. Despite the size difference over Greymouth they both share similarities; all the drive is below footboard level and the open cabs precluded its use for batteries etc. The body is easily removed with four bolts and unplugging the two motor wires. The body is in four main sub-assemblies, footboard, cab, bonnet and transmission bonnet/radiator.

The photo shows the principal assemblies; the footboard with batteries, chassis, cab, bonnet, radiator/transmission bonnet and cab details.

The body assemblies are straight forward solder up jobs using 018 thou nickel silver sheet and Albion Metals' milled angle iron (this is sharp cornered and square unlike some suppliers). Two temperatures of solder were used during assembly to prevent unintentional dis-assembly, if you see what I mean. Getting the prominent radiator right was key to the look of the loco and was tackled first using a cardboard mock up to get proportions right. I should say I had no drawings and the loco was built using a single three-quarter view works photo as reference. On completion of the model two better side elevations came to light, that showed the model was slightly too long, but the proportions were okay. Anyway, the radiator headers were fabricated from nickel silver sheet and the tubes made as per Greymouth from mesh pulled round brass tube.

Again, I had no cab details but the open cab made detailing mandatory. Ron Redman's book again provided similar cab pictures which gave inspiration. The cab details were made from brass sheet, sections and copper tubing. The control levers all move and the duplicated ones move together.

A battery pack is mounted on the footboard inside a plasticard box and secured by 8ba studding. The charge plug and on/off switch are mounted under the small transmission bonnet. As Ethyl was always going to be radio controlled a Timpdon receiver and speed controller were obtained. The controller sits happily on top of the battery pack but to get clear signal the receiver was placed in the fuel tank against the cab backsheet and the aerial runs up inside the fuel tank breather pipe with the tip of the aerial sitting just below the cab roof. This also meant the receiver is as far away as possible from the motor in case of interference. Lights are yet to be made and fitted but the Timpdon unit has switching light facility.

As the loco doesn't fit into the ethos of my railway I had to devise a raison d'etre. Fortunately, Hudswell and Hunslet often tested locos on local lines. This is why I have two locos built for sugar plantations in Queensland and Natal running on my sleepy Yorkshire Dales based railway! This decided the livery. Therefore Ethyl is painted in lined works grey as it appeared in its works photographs. The loco also awaits it radiator nameplate as well as its makers' plates from Narrow Planet.

The photos show the finished locos enjoying early spring sunshine.

Tony Wright February 2018






Contact Us | ©2007 Yorkshire Group