Posted By David Leech on 17 Apr 2010 10:47 AM
Posted By main131 on 17 Apr 2010 04:03 AM
Thanks Chris for information.
As you know Accucraft list both on their web site although the prices are the same.
I am not unhappy about the gas firing.
A sprit fired version as well as gas would I suspect make the manufacturing a bit too expensive. (plus the cost of a fire extingwisher that is mandatory with spirit fired engines....just a joke!
However, they did it for the Royal Hudson!
I'm sure that to make the boiler both ways would not be any different in cost.
The cost of a gas tank or an alcohol tank must be similar.
A wick burner is probably less expensive than gas burner.
It would be interesting to know if there is any real difference in total.
As they are not building thousands at a time, I'm sure that there is probably no savings in volume either.
All the best,
David Leech, Delta, Canada
David:
I think an alcohol boiler would easily take more work to make and cost more than a gas boiler. F4/F5 boiler; a gas boiler would be just a copper pipe with two flue tubes and a few bushings. The alcohol boiler would have several smaller fire tubes (how many, 4, 5, 6?), a fire box with cross pipes (stays?). The alcohol boiler has a sealed smokebox, blower piping and the backhead has more parts with the blower and all. A gas boiler has a simpler open smokebox. The alky fire tubes alone from the posts/threads of those who have made their own boilers definitley showed it takes more to make a alcohol or coal boiler than a gas boiler.
It mostly comes down to labor costs, the most expensive part of making most anything. Even making only fifty or a hundred boilers, the simplicity of the construction will complound labor savings as testing and quality control will be easier.
A gas boiler with two flue tube will have 6 solder joints (2 boiler cap and each flue to cap (4)). An alcohol boiler with 5 tubes and boiler caps has 12 identical solder joint points, plus others as well. More fire tubesm, more solder joints and quality control points. Similarly for the differences between the fuel tnaks. The materials may be closer in costs than this shows for the labor, etc.
Maybe someone can comment of the Accucraft. Dick Abbot's Hundson alcohol versus gas fired construction and costs.