British 0-4-0 Toy Locomotive: he said

[zeeprogrammer]

Guests went to bed early....

Newbie question alert! Newbie question alert!

So I made an adaptor to fit a valve stem to the boiler.
Just for fun, I attached it to the boiler, plugged things up, attached the pump, and pumped away.

I had no expectations this would work. And it didn't. Initially it wouldn't hold hardly anything. After tightening (by hand) the various joints, I could pump it to 50 psi but it would quickly leak out.

I understand I need to do this with water. And the leaks (I'm hoping) are just poor joints that should be fixable with a bit of pipe tape (teflon).

But I'm not quite sure I understand why water rather than air to test the boiler.

Certainly air is more compressible...but are there other considerations?

Having asked that...this is the mountain bike pump that was suggested earlier in the thread. If the boiler is sealed properly...what should I expect? Pump it to some pressure (e.g. 50 psi) and the gauge should sit at that? Or will the pump itself leak and the gauge is worthless for this purpose?

Thanks.

 

[larry1]

Zeep, No answers to your questions ,but a really big welcome back from travels, hope all went well for you. larry

 

[cfellows]

The reason for not using air is this. When you pump any kind of enclosed tank up to 100 psi of air, you have a very large amount of potential energy stored in the compressed air. If the tank fails catastrophically all that potential energy is released at once and you get an explosion that can do a lot of damage.

When you pump the tank full of water, it doesn't compress so there is very little or no potential energy stored. Once the tank is full, you add very little additional water to bring the pressure up to 100psi. If the tank fails, just that small amount of "extra" water is released and it doesn't explode.

Chuck

 

[rcmadness]

If I understand what you are doing correctly. It is safer to pressure test with with water because it does not compress, you want very little air space when you pump it up. If it leaks the pressure dissipates rapidly and it typically a limited release. Imagine a water rocket, the red and white ones that you pumped up with a hand pump, pulled the red keeper back and it took off with great force. Now if you ever fired one of those you know that if you filled it nearly to the top with water if wouldn't do anything. It might have enough power to jump off the holder and fall to the ground. 1/2 full of water would having you trying to find it in the air before it came back down and hit you in the head.

Same principal here.

If you were to test it with air only you would need to submerge it in a water tank (weighted down and body parts way back) and apply the pressure. If it were to fail the water around the tank would keep the metal fragments from getting plumb out of hand.

 

[zeeprogrammer]

Thanks for the 'welcome back' Larry1.

Thanks Chuck and rcmadness. Very helpful explanations.

......................

Uh oh...I see 'bidness' wasn't taken care of in OK. Well...they did say they didn't have a car and it might take a while. ;D

 

[steamboatmodel]

If I understand what you are doing correctly. It is safer to pressure test with with water because it does not compress, you want very little air space when you pump it up. If it leaks the pressure dissipates rapidly and it typically a limited release. Imagine a water rocket, the red and white ones that you pumped up with a hand pump, pulled the red keeper back and it took off with great force. Now if you ever fired one of those you know that if you filled it nearly to the top with water if wouldn't do anything. It might have enough power to jump off the holder and fall to the ground. 1/2 full of water would having you trying to find it in the air before it came back down and hit you in the head.

Same principal here.

If you were to test it with air only you would need to submerge it in a water tank (weighted down and body parts way back) and apply the pressure. If it were to fail the water around the tank would keep the metal fragments from getting plumb out of hand.

The Largest "metal fragment" is apt to be the boiler itself. Back to your water rocket analogy you can launch them from underwater and it does not slow them down much. The only safe way to do a Hydrostatic Boiler test is to do it with the water in the boiler.
Regards,
Gerald.

 

[zeeprogrammer]

Well...I might have a boiler.

Thanks to Pete's suggestion (as well as everyone else's help on the valve etc.)...I got the mountain bike shock pump set up with the adaptor I made last night.

Pumped to about 57 psi or thereabouts. Boiler will (should) operate at about 15 psi.

It's been nearly 10 minutes now and so far no leak. I thought there was up by the gauge (which is not a problem for the boiler) but that might be just drips.

Just saw your post Gerald...thanks.

..............

As a side note...I went out yesterday looking for liquid sterno. But the sporting goods store has gone out of business. Went by KMart and saw some Coleman liquid fuel. Will that work for the fuel tank?

Marv has suggested some 'varnish remover?' but I need the name of the brand. This is very different from what I'm used to and I don't want to get the wrong stuff and 'experiment'.

..............

As another side note...I saw Bogs' reference to the 'Tutu brigade'. I've never heard of a 'brigade of one' so I must not be alone. Better 'out than in' they say...so fess up.

And remember the old saw...'Methinks thou doth protest to much'.
Eh Rick? Jim? Dean? How about you Marv? :big:

 

[mklotz]

Marv has suggested some 'varnish remover?' but I need the name of the brand. This is very different from what I'm used to and I don't want to get the wrong stuff and 'experiment'.

I think what I said was that (methylated?) alcohol is sold as shellac thinner in some of the big box stores. At OSH, you can't find cans of "alcohol" among the cans on the shelf but you can find shellac thinner. I use it in all my alcohol lamps and it works just fine.

If you can find a clerk in the store who looks to be over 50 years old and has no tatoons or piercings, ask him.

Occasionally I've used Coleman fuel in an alcohol lamp and it seemed to work well.

Liquid Sterno may be available from commercial restaurant supply houses, such as Smart & Final. That's where I find the large cans of Sterno - the napalm style.

 

[Dan Rowe]

Congratulations on a successful boiler hydro. ;D :bow: :bow:

There is usually a time limit on a hydro but most often it is the length of the inspectors attention span. For a boiler that small 10 minutes is plenty of time.

That is a nice feather for your cap.

Dan

 

[Deanofid]

Zee, I'm going to push against Marv a little bit here, (and no offense, Marv!). Don't use Coleman fuel in your burner. It's almost pure naphtha, very much a gasoline type substance. If you use it as a fuel, the body of liquid fuel needs to be fully contained, as in a camp stove, or Zippo lighter. If you spill a little naphtha while you're running your engine, it will flash, and "woof!" just like if you were to throw a match into a puddle of gasoline. Too volatile for a wick burner with tank not sealed from the atmosphere.

Just get some alcohol! A paint store will sell the purest kind as shellac thinner, called denatured alcohol. You can also use rubbing alcohol, if that's all you can find. Check the drug store for it, and try to get 91% rather than 70%. The higher percentage point, the cleaner and hotter it will burn. Any of the ones I mentioned will work in an alcohol burner/lamp.

Dean

 

[zeeprogrammer]

Thanks Marv.
Thanks Dan!
Thanks Dean. Rubbing alcohol will work? The kind sold in the pharmacy of grocery stores? I got that.

Boiler was tested for 35 minutes...mainly cause T came home with groceries in the middle of the test and I had to clean out the fridge and help put away...and munch a little of the goodies she brought home. ;D

PSI went down from ~57 to 50 but no evidence of leakage. This is the first time I used the pump so I'm wondering if there was some spring back or something.

So I'm a happy guy. And everyone likes me when I'm happy. ;D

 

[shred]

It's always nice to have a boiler test out. For grins, when you're done, instead of bleeding pressure off or whatever, remove a plug-- you'll then see what happens if there's a leak and why we use water instead of air..

 

[Kermit]

Isopropyl -aka rubbing alcohol will work, but you would be better off with the shellac thinning kind. Iso doesn't burn as well and leaves a god awful smell that seems to penetrate everything it touches.

Home depot sells the stuff in quart cans for about 5 dollars or so.

on another track places like Hobby Lobby/Micheals and walMart sell some stuff called lamp oil. The real name of it is liquid paraffin sometimes its called Kerosene. It is the same stuff as J&J BabyOil only not so highly refined and without the baby powder scent and other things in it. :big: Look for an "oderless" type, they are much nicer on the nose. The draw back with paraffin is insufficent air for the burner can cause black soot deposits.

I would recommend that instead of alcohol. Alcohol fires are almost invisible and alcohol vapors can gather in closed areas with still air and create safety issues. Either one you choose has its drawbacks and good points.

Congrats on the good test results,
Kermit

 

[zeeprogrammer]

Thanks shred. I did pay attention when I released the pump. Anticlimactic. ;D Thankfully.

Thanks Kermit. The smell is certainly something to consider. Lamp oil is a good idea too.

Now if I can just get these guests out of here. Wait...burning iso stinks you say? Hm.

 

[zeeprogrammer]

Question...

The pump was filled with water. I see some water got into the gauge.

Should I throw a bit of oil down the cylinder and pump it out?
Is there anything I can/should do about the gauge?

Thanks.

 

[Dan Rowe]

Zee, the gauge will be fine it most likely has a brass Bourdon tube and I can see a brass connection. If you plan to use the rig for boiler hydro work oil would be a bad thing because the boiler could be contaminated with oil and that is not a good idea.

Dan

 

[Maryak]

Zee,

Congratulations on your successful hydro. :bow: :bow:

Best Regards
Bob

 

[zeeprogrammer]

Thanks Dan.
Thanks Bob.
.......................................
If I recall correctly, this thing is supposed to run for 20 minutes or so.

It's not permanently mounted to the loco. It attaches to the cab with a nut and the steam dome is mounted with a bolt.

I'm thinking I can build a base of some kind and use this boiler to drive some of my other models. However, it's supposed to generate only 15 psi and I know the quality of some of models require more (even much more)....hm...maybe the rocker...I can run it on lung power. But then...there's no throttle.

I'm thinking I've got more to learn yet.

 

[Foozer]

I'm thinking I've got more to learn yet.

Sounds a lot like what the Bride says to me daily

Doing good Zee, enjoying riding along on your Loco adventure

Robert

 

[Deanofid]

Hiya Robert! Haven't seen you around for a couple of weeks. (Glad you're here!)

Dean