Playing in the garden yesterday

[Tony Bird]

Hi,







Take care Tony.

[ge_rik]

Single oscillating cylinder? Is it geared? It runs at a sensible speed.

Rik

[Tony Bird]

Hi Rik,

Yes, a single acting oscillating engine. Yes, again geared 4:1. No regulator, speed altered by gas pressure and load.

Better explanation at:



Take care Tony.

[ge_rik]

Hi Rik,

Yes, a single acting oscillating engine. Yes, again geared 4:1. No regulator, speed altered by gas pressure and load.

Better explanation at:



Take care Tony.

Thanks. That makes a lot of sense. I like the notion of blowtorch firing. Presumably a precursor to gas firing.

Rik

[Tony Bird]

Hi Rik,

I like the notion of blowtorch firing.

The blowtorch works okay but has really to be lit while it is outside the boiler.

Presumably a precursor to gas firing.

I don't think so. Merlin/Beck were using poker burners in the late 1970's. I think the reason was simplicity. I think the design criteria was along the lines of; the model doesn't have anything it didn't need to work. Hence no regulator or safety valve. Motive power one single acting oscillating cylinder with no reverse. Using gears meant that no side rods were needed. The burner being from a pencil blowlamp.

I haven't made a Cracker since 2010 and I always said i would make a 7/8" scale version. Well I have recently started making one. To try and keep it as simple as possible I am using Meccano wheels and gears, The single cylinder will be double acting from a Mamod locomotive.

Take care Tony.

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