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Posted: Sun Nov 03, 2013 4:51 pm
by Chris Cairns
Probably the first meths burner made for the Mamod SL locomotive was this Merlin Works one (from 1981).

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It has separate tubes to the 2 wicks. However the wick tubes are not very tall so that restricted how much meths you could put in the tank. I am extending the wick tubes with some brass tubing which will make this burner more efficient and allow more meths in the tank. Disadvantage of fitting this burner is you have to remove the chassis spacer plus the screws & nuts that hold the bottom of the cab floor to the chassis frames.

And here is a plan for making a "chicken feed" meths burner which I found some time ago on the internet (URL no longer valid). Note however that the needle valve (Dusennadel) is not actually shown in the diagram!

Chris Cairns.

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Click to download file

Posted: Sun Nov 03, 2013 10:41 pm
by The Denying Dutchman
The chicken feeder in the Pdf file is a nice design and with my Salem coal bunker I can hide the fuel tank there. Quite some work, but I like alcohol better than gas. Alcohol is cheaper and it's silent. (besides the Saito vaporising burners) I so dislike the noise some gas burners make! A steam engine shouldn't sound like a jet engine, especially if you paid thousands of Pounds for it. :?

Posted: Mon Nov 04, 2013 5:36 pm
by jameswmorgan
Hi, Chris
The regulator is indeed Dreamsteam, but I put the locking nut on first, then the horn over the nut and the control nut (for want of a better word) locks that in place, so it's basically friction driven.
The linkage is spring steel, giving some pressure when in the 'off' position and I've set it for a short travel. This gives (usually) the right amount of steam to the pistons so it doesn't bomb off down the garden. Once bitten twice shy on that front. I might try for more travel should I get the reverser sorted out. That way there will be dual control over acceleration.
The magnet is from a strip I got from a bloke on ebay selling corridor kits for 00 coaches. There's lots of it under 'self adhesive magnetic strip' but be aware of 'toupee tape'. Different application entirely.
Jim

Steam Oil Lubrication

Posted: Thu Nov 07, 2013 11:41 pm
by Chris Cairns
These basic oscillating cylinders rely on wet steam for their lubrication which combined with the wobbly wheels with their loose crank pins & loose bearings leads to early failure of the pistons & cylinder end cap.

MSS introduced an improved cylinder end cap which being thicker around the piston meant less steam leaks from that area. However recent MSS cylinders produced no longer have these improved end caps fitted, either by choice or a lack of available parts.

Whilst I'm aware of the method of injecting steam oil into the main steam pipe by removing the steam dome, a recent discussion elsewhere in this sub Forum has proved that the boiler insert for the steam dome nut had changed over the years of Mamod SL production allowing the fitting of an "O" ring as the seal. I've tried fitting an 'O' ring to early Mamod SL's but they have either never sealed properly or lasted very long so resorted to a suitable punched washer instead. Thus I have always injected steam oil via the holes in the cylinder back plates.

This MSS has an 'O' ring fitted steam dome so as I have a blunted needle & syringe which came with my first Cheddar Models steam engine I decided to try injecting steam oil via the main steam pipe after removing the steam dome. The blunted needle fits into the bore of the 1/8" steam pipe so it is easy to push the steam oil well down the pipe and then by placing the reverser fully forward and rotating the wheels forward the oil is drawn forward into the reverser & cylinders thus avoiding any being sucked back into the boiler.

As I do not intend running this MSS in continuous steam filling up the boiler & meths burner as required, but rather stopping to fill up manually after each run I'm hoping this method of lubrication will help reduce the wear on the pistons, and I'll see how the 'O' ring holds up on the steam dome to repeated removal/replacement.

Chris Cairns.

Check your Coupling Rings!

Posted: Sat Nov 09, 2013 8:18 pm
by Chris Cairns
Found out a useful experience the hard way.

Visited the HGLW this afternoon and watched an MSS & IP Jane running round OK before it was my turn to run my MSS & tender combination.

Apart from some loose gravel causing the odd problem I was mythed as to why my MSS & tender kept derailing. The answer lay in my use of the old style Mamod key ring type coupling ring. Whilst this works when running round a standard Mamod loop with linear curves, the changing radius of the HGLW curves was enough to cause the buffers to lock up leading to the derailments. After removing the tender the loco finally managed a complete circuit of the layout without derailing.

So back on go the MSS oval couplings.

Chris Cairns.