Boiler water

[GreeboTheCat]

Do I have to buy distilled water for the boiler or will ordinary filtered tap-water do. We live in an area of high calcium content so we always filter our water for use in the kettle and it seems to keep the kettle pretty clean. Will this filtered water be ok for my boiler.

Greebo

[steamboatmodel]

Hi Greebo,
It is better if you use distilled water. Having said that I must admit that most of the time I use tap water. You can just plain water, but you may have to descale yearly.
Regards,
Gerald

[derekwarner_decoy]

Hi PD's...Greebo...in an old OFFLINE posting, Sandy mentioned...that he preferred copper over brass for tube work & "filtered or distilled water is fine but what ever you do.....NEVER use de-ionized water"...at elevated temperatures this attempts to re-balance it's ion level & literally eats brass away..appears that the same didn't apply to copper...so this was more to do with brass tube work than copper boilers

In OZ we have a product called CLR..... clears & removes [calcium, lime, rust] from eg., your kitchen kettle - amazing product

[bogstandard]

Greebo,
As Gerald, Derek and Sandy says, preferably distilled, but gets rather expensive.
I would use your filtered water, and keep a lookout for scaling. It is fairly easily removed.
I also used to use a stainless steel thermos flask, and take hot water with me to the lake, saves a lot of warm up time and fuel. Enough for about 3 x 40 minute runs.
I have been using tap water in my boiler for well over fifteen years, and only now just considering a flush out (somehow I have got some steam oil in there). But I do live in a fairly soft water area.

John

[derekwarner_decoy]

Goodness PD's...bogstandard should watch what he gives his boiler to drink....steam oil  & the following is not directed at John....as I know I am not capable of teaching an old experienced DOG new tricks 

Sandy also covered this subject a few years back & suggested a tea spoon of kitchen liquid washing detergent to a 7/8 full boiler & bring to the boil & then tip out & repeat a few times.......& each time flushing with clean near boiling water

Steam oil on the boiler internals and externals of the water tubes would change the surface tension of the boiler water to the metal and marginally lower the heat transfer back to the boiler water...but I guess the resultant change would be 0.000000001 of a % reduction varaince

Sandy did note .....that on no occasion should any petrochemical clearner be used with model boiler internals...where is that emiticon of the rocket Eddy??

regards

[bogstandard]

Hi Derek,

All I can think of is that when the boiler cooled down, somehow some oil got sucked back from the lubricator. Maybe the cooling of the steam caused a drop below ambient pressure.
All I can say is that it makes a terrible mess, can't see thru the sight glass.
No matter what Sandy says, it is going to get a dose of some sort of degreasant, maybe Gunk, before I start the descaling  and refurb process.

Should be good for a few more years as a test boiler for the workshop.

John

[derekwarner_decoy]

?? Hi PD's......cannot understand John 

a) if the pressure in the boiler = say 1 Bar, the pressure acting upon the oil in the lubricator = 1 Bar

b) if the diameter of the boiler internal is 100 mm & the diameter of the lubricator is 10 mm, we have a volume area ratio of or for [fixed] expansion at equal pressure = ZERO...so we must change the balance of volume by a change in pressure

c) to get oil from the lubricator under [pressure+turbulence] back to the boiler internals.....the boiler pressure needs to be vented to partial atmosphere....    ...whilst the lubricator is isolated on the discharge side.......

PD's is so quiet at the moment & live steam still the  best folder....so if you could comment here would be appreciated by all members

regards

[GreeboTheCat]

It IS VERY quiet on PDs at the moment, I was thinking the very same. Anyway, as the word "lubricator" was mentioned... oo er missus as I'm about to test out my system for the first time, how much oil  (steam oil of course) do I put in the lubricator. Also, as I'm a complete newbie at starting up a steam plant, is there a recognised sequence to the process?

Thanks Greebo

[derekwarner_decoy]

>>>>>> Hi PD's &.......Greebo...providing you have purchased a QUALITY lubricator component....all of the engineering has been pre calculated

The lubricator function [amount of displaced oil] is relative to the steam pressure & volume passing through it....so that volume of steam is also subjected to the orifice in the lubricator & hence forms droplet/s of water [heavier than oil] so displaces the same volume of steam oil into the steam path toward the engine

So just fill the lubricator to the top [good quality steam oil] prior to your first bench steam test & then monitor the spent steam discharge without getting burnt 

The spent steam [prior to your de-oiler] [oily steam to water seperator] should be oily to the thumb & fore finger

Naturally the first few bench tests are critical in confirming the amount of steam oil consumed per boiler fill

There is literally no adjustment possible so functionality will depend on the quality of the manufacturer - you could do Goggle search on displacement lubricators for model steam & spend two days of interesting reading

[GreeboTheCat]

Thanks for the info Derek. My Lubricator (and in fact most of my steam plant) was sourced from that well known Scotish purveyer of quality steam equipment, otherwise known as Sandy from ACS so I think the quality aspect goes without saying 

Greebo

[derekwarner_decoy]

Hi PD's......Greebo also asks " I'm a complete newbie at starting up a steam plant, is there a recognised sequence to the process?"

I am hoping that a more experienced member will respond here..but ask a few more questions firstly about your propsed tests

a) are you going to bench test with the steam drive out of the vessel or bench test the set up in vessel in the bath or pool?
ultimately the latter is the only method of determining actuals with the engine loaded & nominate say 20% engine load/speed for test 1 for one boiler fill, then say 50% engine load/speed for test 2 for one boiler fill etc etc
b) it's more a set of parameters you need to establish once you have a set of recommended sequences,,, like
c) consume one full tank of gas = what % of boiler water consumed? or visa versa?
d) how many full boilers consumed = the steam oil consumed?
e) remember it is best to complete the initial tests without your oil seperator -  unscrewing the lubricator cap will only confirm oil at the same full up mark as you installed - it is the remaining oil ......& the % of water below that you need to benchmark as a function of the number of boiler fills

Seems like more than ...so I will be interested to see a set of generic procedures prior to steaming....regards 

[GreeboTheCat]

GOSH    er...
I must admit that my testing was going to be a bit more basic than that but then I am a newbie 
My plan was to run it all up on the bench to mainly verify that I had steam-tight connections and that the engine DID turn under steam power etc. etc. then the plan was to take it to the pond and let 'er rip. Only kidding, I am if anything a bit over cautious when it comes to first flights or first sailings but I hadn't really put much thought to how long a boiler full of water would last. Also, once I've sorted out all the bugs and got a few afternoon's sailing under my belt, I start thinking about the next project which you'll be pleased to know is going to be a Paddler  . How about this though... my missus is so impressed with the look of the steam launch she actually said I could keep it in the house on show!

Greebo

[malcolmbeak]

Hi Greebo
I've been following this thread with interest. Just a few observations
Testing: Certainly run the plant before finally mounting it in the boat. If possible have a small test tank with a shaft and prop fitted, and run the lot under load. Definitely see how long the fuel and/or water last. At least with an open launch you should be able to see how the water level in doing.
Water: I've been running my launch for over 20 years now, most of that time with automatic water level control, and have always pumped straight from the pond. The boiler has never been de-scaled. The water at St.Albans is pretty foul considering the number of ducks and geese around. It still steams well, so I don't think I have any problem with scaling up.
Lubrication: Let me say straight away that I don't like lubricators where the steam passes straight through, I always mount mine to tee into the steam pipe. On one of my early plants, I was using quite a lot of super heat, and the straight through lubricator got so hot that no steam condensed after the first few seconds. I also like to have a needle valve in the lubricator so I can control how much oil is fed in. All a bit of trial and error, but with a bit of experience it is easy to use.
The picture shows the plant in my launch, and hopefully you can see the lubricator (the chipped black thing) and needle valve.
Malcolm

[bogstandard]

Derek,
Sorry to keep you waiting so long. The only way I could see oil being sucked back is by having the throttle closed, so that the boiler and all lines were below ambient when it cooled down, and when I moved the throttle it sucked air and any contents in the lines straight back to the boiler. That is the only explanation I can give, as I was scrupulous in what went into the boiler filler hole.


Everyone else.

This is what I knocked out a couple of weeks ago for some lads that have 'toy' engines as they call them. The first two pics show offset (the type Malcolm prefers) and inline lubers.  For horizontal or vertical steam lines. No adjustment on these, but the lads love 'em, they can steam their little engines for about an hour before they need to be topped up. The tall one was a special for 3/16" pipework, for a chap in Canada.








These pics show the matching oil catcher for the lubers. These are a necessity if sailing, as the local councils don't like oil being dumped in their already polluted and duck crap ridden lakes. This one was made from large bore plumbing pipe and a few bits of brass and copper.






John

[derekwarner_decoy]

Hi PD's ...&  ...is it an optical illusion Bogstandard....that in your "oil catcher"....

a) The inlet with the dog-leg is 1/8" OD & the straight discharge is 5/32" OD copper tubing?

b) You may need to explain how this works? as I could only visualise the oily discharge steam entering the deoiler & spraying onto the inner walls or a baffle & the oil component being released from suspension & the clean steam carrying on

c) In the ACS website....an American modeler has an ACS deoiler which can be isolated & as such is a pressure vessel - Sandy confirmed dished ends & a such was of a higher rating....however I see your CREWE Eng variant has a removable brass lid/cap......I hope this is a solid brass cap [100gms?]

BTW...the polished copper & brass in one component certainly looks the part