Blower Line

[hoppercar]

I always planned on running my blower line outside the boiler, under the running board, as per my prototype i am modeling.....but after completing the boiler, and mounting it to the chassis..i sometimes have second thoughts about that?....I see locomotives with the whistle mounted up near the smokebox, with a long steam line, so i cant see where running a line under the running boards, and thru the smokebox would be a whole lot different and let the steam cool to much...its a 5/16ths diameter line......was just wanting other thoughts on it.....thanks

[Builder01]

Many miniature locomotives use a hollow stay to get steam from the back head to the fire box and then to the blower ring. This keeps the blower steam line hot as it is contained inside the boiler. I understand your boiler is finished, so it is a bit late for that approach. Many things are changed for practical reasons when building a miniature. A well designed prototype does not always make for a well designed miniature.

A long pipe to the whistle is to be avoided if possible. You will always get much water out of the whistle when initially blowing it.

Hopefully others will have a solution for getting an external steam line to the blower.

David

[NP317]

Both my locomotives have the blower line passing from the back-head to the smokebox through a hollow stay.
This keeps them hot and minimizes condensation.
In the attached pic of my Ten Wheeler, you can see the black-wrapped blower line going into the hollow stay in the back-head, just to the lower left of the angled throttle lever.

An alternative for external mounting is against the boiler shell and under the jacketing. I've seen that on prototype locomotives.
~RN

[RET]

Hi hoppercar,

Using a hollow stay is the conventional way to feed a blower, but since you don't have that option, there are a few other possibilities.

You could use thin wall stainless tube (lower thermal conductivity) to do what you have in mind, but where possible run the external line under the boiler cladding to minimize heat loss. With that method, you should also have a small hole in the tubing at a low point to drain any condensation that may accumulate. The hole could be inside the smokebox and it would also make sense to have a small coil in the smokebox to pick up some heat before the line connects to the blower.

Another possibility is to run the blower line down the outside of the backhead into the firebox and through one of the lower tubes into the smokebox. A little messy looking, but quite practical.

I assume that this is 7 1/4 or 7 1/2" gauge. Since you have full boiler pressure available, 1/4" thin wall stainless tubing should be enough for a blower line and a high flow rate would reduce condensation. The other advantage in this application over a whistle is that a blower needs steam ALL the time.

Just a couple of ideas which I'm sure have been used before by others.

Richard Trounce.

[10 Wheeler Rob]

A 3/16" OD copper tube will supply all the stem needed for the blower, 5/16" is way bigger than necessary. 3/16 is much easier to route.

[cbrew]

I run my 3/16 blower line under the running board as prototype and do not have any issues with cooling, but just remember its there when reaching under the running board

[Marty_Knox]

Run it outside. Put a tee and then a valve for an air connection. Just like a real locomotive.

[uncle jerd]

What Marty said