Author Topic: Pennsylvania A3 Switcher (Kozo)  (Read 356964 times)

Online Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #2580 on: March 19, 2023, 03:56:50 AM »
Thank you Dave, Jeff, and Steve,

I'm guessing that you will be able to patch these little areas up and move forward?

Dave
Most definitely.  It's just the minor irritation of having to do another round of soldering before I can move on to the next step.  But I'll get there! :)

Yes, Steve, I'm gainin'  :Lol:

Kim

Offline bobh

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #2581 on: March 19, 2023, 12:03:03 PM »
Does the pickle bath get it clean enough that you can just ad flux, solder and go at it again or do you have to get in there and mechanical clean the joint first? Bob

Offline fumopuc

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #2582 on: March 19, 2023, 12:22:30 PM »
Hi Kim,
nice progress over all.
Kind Regards
Achim

Offline Admiral_dk

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #2583 on: March 19, 2023, 12:55:48 PM »
It is progress - no matter the speed + the flowed areas look very good  :ThumbsUp:

Per     :cheers:

Online Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #2584 on: March 19, 2023, 03:49:06 PM »
Thank you Achim and Per!  :cheers:

Kim

Online Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #2585 on: March 19, 2023, 04:11:58 PM »
Does the pickle bath get it clean enough that you can just ad flux, solder and go at it again or do you have to get in there and mechanical clean the joint first? Bob
Hi Bob,
Yes, it comes out of the pickle very clean!  However, since I usually don't get around to doing the next round of soldering for a day or two I usually buff up the area just a little with a scotch brite or wire wheel in my Dremmel just to be sure to clear away any oxidation that has occurred.  Not sure that it's necessary, but I do it regardless.  It takes very little time and gives me more confidence.

I'm using a citric acid bath for my pickle.  It works quite well but it takes several hours to clean all the flux and soot off the copper.  I don't know if that's always the case for citric acid, or if I'm using too low of a concentration (though I did try and saturate the solution as much as I could) or if my pickle bath is just too dirty (it is rather dirty - lots of soot and muck in it).  But it's working for me.  And I generally haven't found it too much of an inconvenience to leave the items in the pickle bath that long.

If I'm willing to do more mechanical cleaning work, I sometimes only leave them in the pickle for 30 min or so to neutralize the flux then wash them off and use a lot more scotch-brite/wire wheel to clean all necessary areas.  It just takes more work and the rest of the part still looks less bright. Which I guess doesn't really matter since I'm going to be heating it up and getting it all ugly again.

I have used Sparex in the past and I feel that it worked faster than the citric acid.  But citric acid seems less caustic to me than even sparex, which is much less evil than a standard sulfuric acid pickle.  But the main reason I went with the citric acid is that it was much cheaper for me to make a BIG vat of it - big enough for my boiler.  The Sparex would have been much more expensive to make that large of a pickle bath.  Also, seems harder to dispose of.

Kim

Offline Michael S.

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #2586 on: March 19, 2023, 05:48:06 PM »
It looks like the lord of the boilers is slowly coming to the finish line.
Very good progress.

Michael 🍻

Offline internal_fire

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #2587 on: March 19, 2023, 06:36:52 PM »
Citric acid pickle is quite temperature sensitive. If there is any way to warm the solution even 10 degrees the action will be faster. (Or you can just wait, unless someone is paying by the hour.  :))

I find those corners in the mud ring (foundation ring) to always be troublesome. There is nothing pushing the edges together, and it is not easy to manage a really close clearance without some help from screws or other clamping features. I suspect that the heating required for soldering causes some movement as well.

Time for the swarf, wire, shim stock, etc. to fill the gaps. Strength is not the issue, just leaks.

Gene

Online uuu

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #2588 on: March 19, 2023, 07:38:45 PM »
When you're re-doing parts of a joint, it's not really possible to mechanically clean inside the joint - the mating faces are fixed by the first fry-up.  Cleaning around the joint makes you feel good, but all the places you can get to contribute very little to the strength of the joint - although they might support a leak-stopping effect.  So you have to rely on the pickle, and then the flux,  to clean things up in the inaccessible places.

Fortunately I've found that you can get excellent results on the second, third (and more) heat-ups - so the pickle and flux must work!

Wilf

Online Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #2589 on: March 19, 2023, 08:31:54 PM »
True enough, Wilf!  I'm certain you are correct there.  It doesn't hurt to buff it up, so I do it.  But you're right - the inside of the joint that really needs to be clean will only be affected by the pickle and the flux.

And to further comment on what Gene said about the citric acid pickle Ė that makes sense about the citric acid bath being more susceptible to temperature.  Itís been quite cold here. Even now weíre only in the mid 40ís Fahrenheit.  Maybe it will work better in summer weather when the temp is higher :)

Kim

Online Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #2590 on: March 19, 2023, 08:34:54 PM »
Short shop session today.

I did exactly as Gene described and filled those gaps with some copper shavings then soldered it again.

It seemed to go well. I soldered it in the same position as yesterday but was unable to inspect the underside that way, so I carefully turned the boiler over so I could see the bottom.


The corner joint (right corner in the picture) came out OK.  Time will tell.  But there was still a bit of a gap along the top of the joint.  So I added a little fluxed solder there and flashed that.  This op took longer to get things up to temp.  I think thatís because Iíd pulled the boiler out some and there was such a large gap between the insulating bricks and the area being soldered Ė it left a much larger heat sink open to the cool air, so it just took more ergs to get that area up to temp.

Regardless, I got it done and that gap is now filled and itís sitting in the (cold) citric acid bath now.

Kim

Online crueby

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #2591 on: March 19, 2023, 09:53:02 PM »
Great that the crework isgoing well. Be careful  pulling the boiler out to check, don't  drop it!!

Online Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #2592 on: March 20, 2023, 01:25:30 AM »
Be careful  pulling the boiler out to check, don't  drop it!!
No joke! I am worrying about that!  :o

Kim

Online Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #2593 on: March 20, 2023, 01:27:10 AM »
Out of the pickle bath now, and rinsed off, it looks pretty good!  Like it should have last night. The problem area is the lower right corner.


And just for fun, I fit the firebox and backhead in place to see how itís going to look:


Not as good as Iíd like, but itíll do.  I didnít put any screws in the back head, itís just kinda snapped in place. So the gaps will be a little smaller, but not as small as Iíd like them to be.  Ah well.  Copper caulking does wonders for my inability to make a close fit.  And it ought to work quite well.

So thatís my next project Ė soldering in the firebox.  Thatís going to be a doozie I thinkÖ

But a doozie for another day.

Kim

Offline steamer

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #2594 on: March 20, 2023, 01:40:55 AM »
It's certainly getting there Kim!   Almost there, and then get the hydro and you'll be good to go!

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

 

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