The Steamboating Forum

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I have had near perfect service from a hot well float for boiler level control. It is so good that it is perhaps dangerous since the level doesn't change from hour to hour and I get complacent about keeping an eye on the gauge.

The only change in level is from using the whistle a lot ( I'm really bad about this) and popping the safety (not so good at planning ahead). With wood firing there is the obvious lag between stopping the wood chucking and less heat. I have a tight fire door and draft but even then I get careless and waste water making noise and scaring dogs.

thank you very much. I am re-installing th stuart 6a and it has a mechanical pump. Based on the opinions of others here on the forum, I have decided to reduce the volume per stroke of the pump and thus reduce the possibility of noisy cavitation. As an aside, whoever did the machine work on my 6A made the bore .782 and the piston is only 0.732. (WOW) I did not machine these! I found the whole engine on EBAY at a great price and I have FIXED all of the machining shortcomings so far. On this problem , cavitation, people say reduce the frequency with gearing by 2/3. Fine, but I will simply sleeve the bore and piston so that instead of having a 3/4 piston, I will have 1/3 X 3/4>> .250 piston. If it cant keep up, I will increase it later. This to me will be a much better solution than any complex gearing might make.
This plan reminds me of what the great George Burns responded about the sexual risk of having a 25 year old partner. "if she dies, she dies!!"

Unless your feed water to the pump is really hot, I suspect you are not having cavitation problems. More often it is valve noise from too much check valve travel. Limiting that is a better idea than reducing your pump volume. Any travel much more than 1/4 of the valve diameter is wasted movement.

There will be times when you want the extra pump capacity for catching up on the boiler level. In most small power plants like ours, the pump capacity is at least 25% above normal needs.

@ DetroiTug and Wsmcycle

Hypro pumps are indeed good pumps and many people have them (I do off a toothed belt and is less noisy than a chain). Be sure to fit a good strainer and no oil in the supply line as the small check valves will stick, but this usually means you have other problems. When they dont work, it is usually always the check valves or an air lock.

I have found that a good "special tool" for removing the check valves is a simple paint can opener. Two are better, slide them into the plastic grooves on either side of the valve and pop them up. They are also small enough to fit under the valve when it is facing the other way.

DetroiTug wrote:Most of these injectors 1/2" etc are really too big for our types of service. Injecting water too quickly that would kill a boiler in short order under way.

Do it in batches. I'm practising firing at home. I was practising operating bounded between 175 and 200PSI with my 1/2" injectors. Just make the batches shorter and more often I was injecting a minute or two every 10 minutes or so. I will grant you my boiler is on the larger side for a launch.

DetroiTug wrote: A better candidate would be a 3/8" or less, even the 1/4" scale locomotive types would probably be ample. Also, feedwater needs to go through an economizer for overall better output. I learned early on injecting cold water in, even a little bit is very hard to overcome with the fire.

I'm very confused by what you are saying. Feedwater with a steam injector is never delivered cold. It's delivered hot.

-CB

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"If it isn't making steam, it's getting rid of it"

That's an important adage to bear in mind.

The inventor of the first wheel was an idiot but the guy who invented the second wheel to use with the first was a genius!

The guy who built my hull had a previous career with wheel design. His first attempt was square. The complains of, "Too many bumps" sent him back to the drawing board. The new design was triangular. "Fewer bumps!"

Now THAT is human evolutionary intervention at it finest!

Hung like Einstein, Smart as horse