Garden Railway Forum

Im thinking about building a Garrat from a Mamod SL1.

A few questions.

Do you think a Mamod SL1 boiler will power 2 Mamod chassis??

Where can I get flexible steam pipe from??

How do you link up the 2 power bogies to the main boiler section??

Does it all need balancing so the boiler section doesnt drop down??

Will the steam condense into water because of the long pipe run to the power bogies??

Any pics of Mamod Garrats or similar would be useful aswell

In answer to the first question I think the answer is No, sorry !

I have concluded that the boiler has a fairly hard job powering one chassis due to its smallish size. I base this observation on my past experiences with my 2 Mamods both fitted with Mike Chaney replacement cylinders and a higher pressure boiler (40 psi), and my Salem loco which is powered by the same cylinders, but weighs much more and has a larger boiler (also at 40 psi), it also has an identical meths burner. The Salem loco pulls much more and does not get "breathless" when the regulator is opened up in order to climb an incline, the larger boiler giving a greater steam capacity. I have found with the Mamods that I need to drive them very carefully, keeping the regulator closed as much as possible and keeping up a slow pace and not wasting any steam unnecessarily when approaching an incline, otherwise they rapidly run out of steam when they get to the incline. I do not need to be so careful with the Salem loco.

HMMMMMMMMMM in that case i may only make the front chassis work

Make the back chassis a fake one. Would that work?

Ive found this pic of a Mamod Garrat

I see no reson why an sl1 boiler shoudnt work provided you can get the steam generation out of it because it has twice as many cylinders to supply. My dads afrikarn just has a single flue and when running at speed or with a heavy train iy runs short of breath very quickly.

I may eperiment in that case

steamyjim wrote:Im thinking about building a Garrat from a Mamod SL1.

A few questions.

Do you think a Mamod SL1 boiler will power 2 Mamod chassis??

Where can I get flexible steam pipe from??

How do you link up the 2 power bogies to the main boiler section??

Does it all need balancing so the boiler section doesnt drop down??

Will the steam condense into water because of the long pipe run to the power bogies??

Any pics of Mamod Garrats or similar would be useful aswell

Sounds like a great plan Jim, but please be aware that a Mamod boiler will not produce anywhere enough steam to run 2 Mamod chassis! You'll be needing somthing like a Roundhouse boiler for that - or if you have that sort of money to spend, get Tim at Chedder Valley Steam to make you one with a ceramic burner, 28mm flue & cross tubes laid out in the 'vortex' pattern.

Flexible steam pipe is available from Alan at PPS. The stuff he sells has a braided wall & will be fine for the job.

As you probably know, a Garratt comes in 3 sections - 2 power units & the boiler/cab which is mounted on a frame.
The frame has a pivot at each end which is normally located over the last driving axle of each power unit. Once you've got it all together, nothing will 'drop down'!

On any Garratt, you'll get more condensate than on a 'straight' loco, but once it's cleared & got warm, it'll make little difference.

As i think i've mentioned, my friend Eddie Bull has built a Garratt using 2 Mamod chassis (which will be at the Pontefract show on Ttarrag Shed this coming weekend), i'll post some photos of it shortly showing various views including the underneath.


Chris.

I think i shall try it with one chassis powered and the other a dummy?

Ill have a word with Tim, good freind of mine See what he can do

Thats good i was worried about it all collapsing But thinking about it it shouldnt.

Aye if you could please get those pics that would be most useful

A mamod boiler should do the job as long as it can get enough heat in it and produce enough steam eg a 5 wick meths burner under an sl1 boiler but then garret 100 is the real expert in these matters.

ptlrcecil wrote:A mamod boiler should do the job as long as it can get enough heat in it and produce enough steam eg a 5 wick meths burner under an sl1 boiler but then garret 100 is the real expert in these matters.

Still laughing here... a real expert.... Loved that one...

Do you know how you find out about boilers...? Failures, that's how!
Having a boiler that you're sure will be fine for the job & then finding that it'l hardly get warm...

Seriously though - a mamod boiler is designed as a toy to be made & sold within the rules & regulations that the likes of Mamod have to abide by. The downside is that although used in the application it's designed for, it's great (the mamod loco must hold the world speed record, possibly eclipsing Mallard...), but it won't do a lot else.
Being a 'pot' type boiler, you just won't get the output from it that you need to do much more than power a couple of Mamod cylinders.
Although the Salem Garratt (not the Locobox version) is also a pot boiler, it's a lot larger & has a lot more powerfull burner.

You have to start thinking big! Or at least bigger...

Chris (Garratt100) (That's Garratt, spelt garratt...)

Ill have to have a fiddle with bits and peices i have at home

I have a nackered 3.5" gauge Titch boiler

garratt100 wrote:Chris (Garratt100) (That's Garratt, spelt garratt...)

Don't worry Jim, the FfR spelt it wrong on their K1 mugs .

Did they

Got a pic of them?

Obviously I didn't buy one, because it's not my style, and they aren't very nice, but it's on the FfR shop site!
http://www.s114502314.oneandoneshop.co. ... 91x206.jpg