Compatibility Slo-mo


Slo-mo adds inertia and momentum to small live steam locomotives for more realistic running. More information and videos on the Slo-mo from SSP: http://smallsteamperformance.com.au

Fitting is a relatively straight forward job following the instructions on the SSP internet site for a Roundhouse Katie and Billy. It's not really necessary to remove the body. However as there are steam pipes underneath a Riverdale boiler two extra steps are needed before fitting the Slo-mo.

First the steam pipe coming down from the boiler and going to the steam-tie of the cylinders has to be bent about 2mm away from the Slo-mo to create ample room for adjustment of the chain later when fitting the Slo-mo (see drawing). To have enough room doing this, set the front wheels maximum outwards, loosen the steam pipe nut from the steam tie and remove the central frame spacer (which needs to be removed for the Slo-mo anyway). Bending steam pipe needs to be done before fitting the Slo-mo and with care preventing too tight curves. Best is to bend the pipe with your fingers as your fingers are nicely soft and round. Start with bending back bend 1, next make bend 2 and finally adapt radius of bend 3 for which I fitted temporarily a Regner M5 nipple to have some length to apply force with my fingers. The steam pipe of the Billy/Elke is more easily bent in place since the boiler sits higher. So loosening the steam pipe nut and applying the Regner M5 nipple is not absolutely necessary.

steam pipe
The trick with re-adjusting the Roundhouse weigh shaft as described on the SSP internet pages for a Katie will just not work for a coal-fired Irene. As a second step it's wise to exchange the weigh shaft with a new one. A new weigh shaft is easily made by yourself by bending a piece of 1/8 inch stainless steel rod in your vice (see drawing below, dimensions in mm). Make sure that both rod ends are nicely aligned and the weigh shaft is minimal 4.8mm deep. I used a 3mm rod as I had nothing else available. Works fine but play is a bit much.
As the Billy/Elke has a straight weigh shaft all this is not necessary when fitting a Slo-mo on a Riverdale Elke.
weigh shaft For Elke you have to find a solution for the whistle because the Slo-mo took its place. A good solution is to fit the whistle inside the right side tank and between displacement lubricator & boiler. See drawing below: 1 = whistle valve; 2 = whistle pipe; 3 = whistle; 4 = M5 union nut. For a 1:1 PDF drawing that can be used as guidance to bend the new whistle pipe open and download this link. Print the drawing at 100%. Shown are front, side and top view of the new whistle pipe. Eventually you need a new clamp nipple for the Regner whistle kit as you have to alter the steam pipe.

elke slomo fluit
For best results you need to exchange the exhaust nozzle. A set of new smaller exhaust nozzles is available optimized for running at realistic speeds to get the most out of the Slo-mo. Under damper control you can run extremely slow without losing the draft (see video).
Because water usage is lower, running time will be upto 25 minutes compared to 20 minutes without Slomo. Running 25 minutes the boiler has to be kept on temperature longer resulting in a higher coal consumption. So make sure you have enough coal in the firebox!

The new smaller nozzles, the Regner M5 nipple and a new Regner clamp nipple are available now.

When fitting a Slomo on Amy spacers need to be removed. To keep the rigidity of the frame it is best to fit them elsewhere, preferably near the bottom edge of the frame. Therefore you need to drill extra holes in the frames. When fitting like the picture below, one of the spacers needs cut-outs for the wheel flanges.

frame spacers
Further a cut-out in the floor plate is necessary for the flying wheel of the Slomo that sticks out above it. And check the steam pipes under the boiler for collision with the flying wheel. In the picture below you see the steam pipes re-bend away from the hole for the flying wheel.

floor plate

However not tested yet, the Slomo for the Darjeeling "B" should fit the coal-fired Darjeeling 'B'.

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