Running an MSS Loco on Solid Fuel & Multi Role Config

[jameswmorgan]

Hi Jim,

Welcome to the Mamod sub-Forum (been very quiet here recently) & the main Forums.

You will need to ask Peter Jones (Superbiker_uk) whether he will be releasing more of these tender aprons. He has posted above in this Discussion, just click the PM symbol at the bottom of his posting to send him a Private Message.

You should be able to attach a photo to postings, although myfreeforums does behave strangely some times (if you have a space within your photo's filename it will probably not upload). otherwise you need to host your photo elsewhere on-line and use the IMG code to embed it in your posting, see here for more details - http://gardenrails.myfreeforum.org/about5505.html

Look forward to seeing some photos of your radio control on the MSS loco in due course.

Chris Cairns.

Thanks, Chris.
I'll contact SB tomorrow. I think the image may have been too large, so I'll apply some shrinkage and try again.
Jim

[jameswmorgan]

Success with the picture. The plan is to further the R/C by adding another servo to operate the reverser, but I'm trying to work out a mechanism whereby you don't have to keep the R/C engaged all the time. We now have a Maplins in Huddersfield, so something might turn up. However, it's way down the line.
As it were.

Jim

[The Denying Dutchman]

So having decided to reserve my accumulation of solid fuel for my stationary steam engines I decided to do a timed session with a meths burner for a comparison in the same loco.

I used my best meths burner, an IP Eng 3 wick burner originally fitted to an IP Jane, which has the best type of chassis spacer which actually holds the burner tube in the right place (later versions have a slot cut into a standard Mamod/MSS chassis spacer which is actually supposed to be mounted upside down but I've seen photos of a few bent burner tubes because owners have mounted it the wrong way up).

Kitchen temperature 20°C, water & lubrication as before, and 16mls of clear meths in burner.

1st run - It took 03:25 mins to get the loco running on blocks properly, then completed 08:34 mins running for 54 laps of the standard oval. Burner continued producing steam for another 02:10 mins but loco would only turn wheels on blocks by then. Total burn time 15:00 mins and 1/4 of usable boiler water capacity left.

Interestingly at no time during this run did the safety valve start weeping.

So looks like the meths burner applies the heating more linearly across the boiler thus taking longer to reach running temperature. And this burner burns as designed with the meths safely running out before the water (just as well as the sight glass plastic has started to craze already and that was only on solid fuel - Mamod say these melt between 150 & 170°C).

Chris Cairns.

I do find it a bit odd that the loco refused to run at the end while the burner was still burning. You should expect that the flame of an alcohol burner is fairly constant.

A four wick burner should work great since the SV wasn't blowing off with tree wicks. What does worry me a bit is the steam line. It gets heated before steam production is able to cool it, so if too much heat is applied the soldering might fail.

[Chris Cairns]

Jim,

Thanks for posting your photo. Your driver (a Rob Bennett Busy Bodies?) has wider boots than my Fireman and his feet are closer together. As those neodymium magnets are cheap enough I'm going to order some to try them out.

Your in cab regulator obviously has a coarse enough thread to allow sufficient control using Radio Control - is that a Dream Steam regulator? For your reverser linkage you could use Qwiklinks on the control linkages which are easily removable. As you are using 27MHz it is best to not have metal Qwiklinks on metal control horns to reduce the interference they can generate.

Paul,

Locos have to overcome several friction points when running on track, thus they run a lot freer when placed on top of blocks. This loco is still running in the cylinders but my method of securing the axle bearings into the chassis frames with Araldite Rapid steel has proved very successful so far with very free running wheels which do not wobble.

The meths burner has a tank from which the burner tube exits out the side near the bottom. Thus they are linear burning until the level gets low, then the furthest away wick starts to go out, and so on till no meths remains. The ideal design would be a header tank "chicken feeding" into a burner tube below but you do not see many of that design used on a Mamod SL/MSS loco, although they do exist.

The reason that the safety valve was not lifting was because I did not let the pressure build up more and just got it running when it had sufficient pressure with the burner keeping up with the demanded volume of steam output. These 3 wick burners can provide 40PSI if you wait for it to build, and would probably be topped up again once pressure had been raised (but that is out-with the parameters for my test comparision). I also suspect that this MSS safety valve is set for a slighter higher pressure than the original design of 0.7 Bar but have no way of testing it.

I have re-soldered the boiler bottom fitting with plumbers solder which has a higher melting point that the Mamod/MSS solder paste and works OK on my other meths burner boilers. It is a ceramic gas burner that I would be concerned about with these soft soldered brass boilers which is why I do not fire them using that method.

Chris Cairns.

[The Denying Dutchman]

A chicken feeder burner is interesting, but I think a burner with a main tube and a second tube feeding the front wick directly, will work just as well. Without the possibility to control the flame to a certain degree of course.

[Chris Cairns]

Probably the first meths burner made for the Mamod SL locomotive was this Merlin Works one (from 1981).



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.


Click to download file

[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.

[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

[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.

[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.