British 0-4-0 Toy Locomotive: he said

[ksouers]

Zee,
I just re-read my post and realized I gave an incomplete answer. Sorry, I'm blaming it on being late and tired.

I guess some definitions are in order.

Wet steam: Steam with significant amount of condensation in it. Usually ignored because it's not a factor except in very low pressure/temperature applications.

Saturated steam: Steam at or slightly above boiling temperature for a given pressure.

Superheated steam: Steam at significantly higher temperature for a given pressure. Usually reserved for higher pressure applications. Only occurs outside the boiler.

Inside the boiler steam is always at the saturated condition.


The rest of the answer:
Superheated steam is hotter (has more energy) than it should be for a given pressure. Or to put that another way, is at a lower pressure than it should be for a given temperature.

By having that small orifice in the line to let steam in it will have a lower pressure in the steam lines, thus somewhat superheated steam. With your low pressure boiler there isn't much distinction between the two, but it becomes significant on high pressure equipment.

 

[Deanofid]

Not to worry Dean. It gives me more confidence in the drawings and instructions when people are telling me the same thing.

Oh my. If I'm thinking the same way as the guys who wrote those instructions... Well, I've
lost the rest of my mind.

I'll just have to live with without it.

Happy Monday, Zee.

Dean

 

[mklotz]

What's astounding is the fact that he thinks it's a good thing to have confidence in the instructions.

 

[zeeprogrammer]

What's astounding is the fact that he thinks it's a good thing to have confidence in the instructions.

Rats. Not what I intended. What I meant was..."it gives me more confidence in my thinking about the instructions".
How about that? Do you buy that? Is cheap.

------------------------------------------

I will be visiting the hobby shop this week. ;D

Soldering the tube to the steam dome resulted in a melted blob of brass steam dome.

I think it's my eyesight. It didn't look like the silver solder was melting so I kept at it.

It's a keeper though. I gotta tack that one to the wall. :big:

On a side note...having annealed the tube the other day made it somewhat touchy putting the silver solder rings on without bending the thing up. It is very very soft.

The bright side...another day without an "I-told-you-so". :big:

 

[bearcar1]

"I told you so"





Does that count? ;D


BC1
Jim

 

[mklotz]

This just in ... Zee hard at work ...

 

[zeeprogrammer]

Jim...uh...what to say...oh yeah...what I said before...gotta watch you.

Marv... :big: Good one. Now you need a pic of Chaplin from Modern Times and you get an idea of me tightening down anything with a bolt.

Kevin...thanks for the explanation on steam.

--------------------------------------------------

Well...since I had a nicely annealed bit of tubing...I thought I'd go ahead and form it...

I was very pleased!

You can also see how the pickling went...that was just after an hour or so.

And...you can see how the brass collapsed.

 

[Deanofid]

Well, it's obvious that your torch has enough heat for this job, Zee!
You WILL have this brazing/hard soldering thing down pat, soon. You're a pretty quick study,
really. Mostly 'cause you're a Tom Edison in the persistence dept.

When you head to town for some brass, have a look in the Ace Hdwe store to see if they have
some refrigeration tubing in the size you're using, just to have a few feet on hand in case you
need it. It will come in a coil. (You don't have to buy the whole coil. They'll cut it to length.)

You know how it looks now, this brazing. When you put the torch to it, first, the flux boils for a few
seconds,then settles down and just sits there. A while later the flux starts to get liquid again, kind of
looking like syrup. Not long now, and the solder gets slightly shinier than it was. It's almost ready to
go then. When you see that, try hitting it directly with the torch flame for a few seconds. Sometimes
it takes a little nudge to get it to go liquid and flow.
That might help. I don't know for sure, since I don't know exactly what you're seeing.
I have a video where I think you can see it. Will upload it and send you a PM.

Dean

EDIT: Just saw your post on the bending. Looks great!

 

[mklotz]

Hey, the bends look GREAT. Just to be fair, I'll take back one of my I-told-you-sos. (The one that said you needed a groove in the bending form.)

In fact it looks so good that I would be tempted to hack off the melted dome and make a new, two-piece one that could be soldered to the tubing.

 

[zeeprogrammer]

Thanks Dean.
Thanks Marv.

Interesting idea about hacking off the tubing...if I can't find the tubing at the hobby shop I may just try that. I hope to avoid it though...the jig needed to keep everything in place seems difficult.

 

[Kermit]

Zee, next time you are at the hobby center store. Look for and purchase some modeling clay. Nothing fancy, just simple clay like we used to make ashtrays and flower pots out of in school years back.

It works very well as little props that form into shape and hold pipe and such in place quite well and also resist the heat very well for the short time it is applied.

Poor mans universal jig - sort of.

Kermit

 

[zeeprogrammer]

Very neat idea Kermit. Thanks for that.

I only go to the hobby shop during lunch hour. Gives me just enough time to get exactly what I'm looking for. No time to hunt around. I'd spend more money.

It helps that the (backup) wine store is two stores down. That cuts down on shopping time too. I'll spend money but I won't get in trouble for it.

 

[zeeprogrammer]

Life is a roller coaster.

Went to the hobby shop.
They got 3/32 tubing!!
Got 3 feet out the door when I remembered it was copper tubing I wanted..not brass.
Went back in.
They don't have 3/32 copper tubing!!

I have 3 brass tubes...so I can experiment. Any thoughts on that?
I can also hack the copper tubes I have and try that.

I also got the clay...anybody feel a need to recommend green, red, yellow, or blue? ;D
I'm thinking red or yellow...might be easier to see things. :big:

 

[fcheslop]

Hi Zee.Nice to see its coming along if you reused the copper tubing would it be possible to reuse you're jig to straighten it up after soldering just a thought.
best wishes Frazer

 

[bearcar1]

Yes but how many boxes of wine did you procure on this outing? :big: You must have a decently supplied hobby center, everytime I go in to the place close by they are out of what I need or they have one and I need three of an item, etc. There is one store in NW Chicago that has been there for years on end and have everything known to man on the shelves. I know what you mean about spending the $$$$ in those places, I have the same problem in the metal supply places.

BC1
Jim

 

[Deanofid]

I also got the clay...anybody feel a need to recommend green, red, yellow, or blue? ;D

Whatever.. Long as it matches the M&Ms!

 

[zeeprogrammer]

Thanks Frazer. I'm (re)making two steam domes tonight. (That's right...two. Just in case.) I'll try one with the brass tubing I got (for the experimentation.) If that doesn't work (experiment fails) then I'll try re-using the copper tubes.

Darn it Jim. I talked about the wine store but clean forgot! I was so hoping for the tubing. I was also distracted by the adjoining grocery store and went to pick up a bread pan to hold oil. I want to blacken my machinist clamp and I don't think I want to use the ceramic pot I had. I was surprised how warm/hot it got when I blackened those half joints I did some months ago.

Whatever.. Long as it matches the M&Ms!

That constitutes a recommendation. ;D Thanks!

 

[T70MkIII]

Yes but how many boxes of wine did you procure on this outing? :big: You must have a decently supplied hobby center, everytime I go in to the place close by they are out of what I need or they have one and I need three of an item, etc.

The trick, clearly, is to procure wine prior to visiting a hardware store. Share with proprietor. You should soon find a noticable improvement in inventory

Forgetting the wine in favour of engineering supplies, Zee? Perhaps evidence of a shift in priorities. Moi? I'd still be getting the wine first, but I haven't started building an engine yet...

 

[zeeprogrammer]

Forgetting the wine in favour of engineering supplies, Zee? Perhaps evidence of a shift in priorities.

Very dangerous. The priority is her. If I run out of wine...there will be no machining. Luckily I had stocked up a few days ago.

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Turned down the flamethrower ;D and soldered the brass tube to the steam dome. Then heated up the tubing and dunked it in water.
Then put it in the mill, eye-balled the 1/4" end mill and milled out the tube.
Then bent it in the jig.

It seems to have worked. As you would suspect, it was harder to bend than the copper...but it did. I don't know how well the solder joint is but it looks like the solder made it from the inside to the outside.

No pics right now...upon successful trimming and setup for the final soldering...I'll get one in.

Ah...being called up to dinner...she wants me to bring up the wine...
What happened to the wine?
Where the heck is the wine?
I'm dead.

 

[mklotz]

French horns are visible proof that brass tubing can be bent. I'm glad to hear that it went well. You deserve to have something go well.

A nice Cabernet on Bastille Day sounds appealing. I must look into that since tonight is our night to eat out. A votre sante.