Calling all Mamod parts! Mamod Garratt?

[Winna Pic & Yucca River R.R.]

This winter I'm gonna try building my first live steam engine! I was thinking a Mamod garratt would be  easy. But I need some parts.

Two working matching Mamod chassis (chassis only; no boiler, cab, tins)

A Mamod boiler (I would love to have an older one because I like the big steam dome)

Gas tank and burner that would fit the Mamod boiler

Any other parts that would be necessary or unique to have on a garratt

One question; would the stock Mamod boiler be big enough to run two chassis even with a 40psi safety valve?

 

[cabbage]

This is actually an idea that crops up quite regularly... I have seen Meyer Mamods,  double  Fairlie Mamods,  Mallet Mamods, and a couple of Garratt Mamods -so the principle facts of building an articulated from Mamods chassis are well known.

The standard Mamod boiler will not produce enough steam for twin Mamod chassis. What you need is the boiler from the G1MRA PROJECT. These are quite common. The flexible steam joints to the chassis can be made from silicone hose, provided you do not exceed 40PSI and no super heat, but you will have to WIRE the hose to soldered on nipples at the ends of the steam feeds to the chassis. 

PPS steam are the people to go to for Mamod parts etc. 

http://www.pps-steam-models.co.uk/

The PROJECT boiler can be seen here

http://www.maccsteam.com/Loco_boilers/Loco_boilers.html

Have fun and welcome to the wonderful world known as "Mamodifications"

regards

ralph

 

[Winna Pic & Yucca River R.R.]

Thank you so much Ralph for the info. I have seen many mamod builds and I think I'm ready to do one. The boiler you told me to look at are a little pricey for what I'm looking for. Any other ideas? Is it hard to make a boiler?

-Patrick   

[cabbage]

It is not that hard -provided you have equipment (air / propane or air / MAPP) that can reach the 600plus Centrigrade that is required to melt "silver solder". I have built a "Porcupine" boiler and these are very good steam raisers. I have collated some articles by myself and others -here:

http://www.cabbagepatchrailway.co.uk/steam+e+d.html

Have a look under the section STEAM.

For 2BAR or 45PSI you are looking at 1.6mm thick copper with three 3mm thick end longitudinal stay bar with 3mm thick end walls to your boiler. Have a look through the articles and decide what you like.

I would recommend a water tube boiler of the "Smithies" type as this is quite easy to make -but you do have to be careful bending the tubes. These should be no thinner than 0.5mm wall and no thicker than 6mm diameter. The easiest way to ensure that they do not collapse is to fill them with salt  or sand after you have annealed them in the flame prior to bending. Make a plywood former to check the curves on the 3 pipes are the same. Oh, and make sure that all your copper is to the same spec -otherwise you will have cracking as it expands under heat!!!

The outer "wrapper" can be lagged with fibreglass sheet and the wrapper made from brass sheet or aluminium. The hot gasses should be able to reach all the surface of the inner boiler before exiting to the air.

When it comes to the "fittings" I would recommend silver soldering brass plugs into place and then tapping them -rather than trying to tap copper -which is dire!!! I should know I have done it....

So, putting together a boiler is actually fairly easy provided you are careful - I would insist that you get it pressure tested before use. It is better to leak cold water than live steam....

regards

ralph

[Winna Pic & Yucca River R.R.]

Thanks again Ralph for more info. I'll have a look at your site but I'm still gonna look around for a premade before I end up with a pile of trashed copper. :O