Author Topic: Pennsylvania A3 Switcher (Kozo)  (Read 29709 times)

Offline Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #450 on: September 16, 2019, 09:40:45 PM »
Really good thought Mike!
I've wondered about that too, figured I'd just line it up as best as I could on the center line after each annealing. But I like your idea way better!

Luckily (?) I've not started this yet, so can still do it the right way.  I've got a daughter getting married in a few weeks and had family in town for the bridal shower this week.  This is a wonderful thing but the side effect is that there won't be a lot of progress on the model engineering front for a while. :)

Kim

Offline b.lindsey

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #451 on: September 17, 2019, 01:00:30 PM »
Congratulations on the upcoming wedding Kim. Enjoy the time with family and your daughter!!

Bill

Offline Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #452 on: September 18, 2019, 06:43:38 AM »
Thanks Bill!  ;D
Kim

Offline Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #453 on: September 28, 2019, 11:33:00 PM »
Got a little time in the shop today.  It's been a while!

After my last update, I was just about to form the sides of the tender.  The left and right sides are formed together as a single unit.  I’d just made the forms and my next step was to start hammering away. But Mike made the suggestion to put some registration pins along the cut line so that it would be easier to get the part back in the form in the correct place after each annealing.  Great idea! thought, I. :)

So I did.  Here you can see the three little brads I used for registration pins:


With that done, I assembled the sandwich former and started pounding away.  Here’s the first round of forming.  Pretty cool!


After an anneal, here’s the second round.


Third round:


And skipping a few, this is after the final round of annealing.  I think I did 6 rounds of annealing.  The last several were only working on the four tight corners.


You can see on this one corner I apparently got things a little too hot while annealing the copper.  It won’t be a problem; I’ll just file it down. But I do need to be careful there!


And here it is after being removed from the form.


And finally, cut in half.


Pretty exciting, eh? :)

Thanks for following along.
Kim

Offline crueby

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #454 on: September 29, 2019, 12:41:45 AM »
That came out great!  How did you cut the two halves apart without distorting the sheet? Looks like the alignment pins probably made a good center reference on the metal for cutting too.   :ThumbsUp:

Offline Ye-Ole Steam Dude

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #455 on: September 29, 2019, 01:05:20 AM »
Hello Kim,

That is some beautiful work.

Have a great day,
Thomas

Offline b.lindsey

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #456 on: September 29, 2019, 01:21:55 AM »
Well done Kim!! Those came out great  :ThumbsUp:

Bill

Offline Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #457 on: September 29, 2019, 05:55:31 AM »
Thanks Chris, Thomas, and Bill!

Chris, I cut the halves apart using my 4x6 HF band saw in the vertical position.  It worked pretty well.  Since it was narrow on one end, I could get it almost 90% through the saw that way. Then I flipped it around the other way for the last couple of inches.

I had planned on using the scroll saw, like I used to cut the sheet out in the first place.  But the band saw is WAY faster.  And since it fit, why not use it, right? :)

Thanks,
Kim

Offline Admiral_dk

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #458 on: September 29, 2019, 07:58:36 PM »
Nice progress Kim  :ThumbsUp:

Quote
Here you can see the three little brads I used for registration pins:

Oh man they are small  :o  How did you make them stay - are they soldered in place ?

Offline Dave Otto

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #459 on: September 29, 2019, 09:37:03 PM »
Nice progress Kim.
The tender sides are looking great!

Dave

Offline Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #460 on: September 30, 2019, 05:23:27 AM »
Nice progress Kim  :ThumbsUp:

Quote
Here you can see the three little brads I used for registration pins:

Oh man they are small  :o  How did you make them stay - are they soldered in place ?

I used a interference fit into the bottom wood form.  For these brads a #55 drill makes a tight clearance fit, so I used a #53 in the maple form, cut the head off the brad and just pushed them into the hole.  It made a nice tight fit and they didn't come out during use.  I drilled #55 through the copper, and #57 in the top piece of plywood.

This way I could take the copper plate off, but the brads stayed in place in the form.

Probably should have show a picture of all three pieces of the sandwich to give you a better idea, but I wasn't that smart :)

Kim

A #55 drill is a tight clearance fit, and that's what I used through the copper.  The brads

Offline Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #461 on: September 30, 2019, 05:24:40 AM »
Thanks Dave!
Kim

Offline fumopuc

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #462 on: September 30, 2019, 05:17:57 PM »
Hi Kim, even if I am quiet, I am following along.
Kind Regards
Achim

Offline Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #463 on: October 13, 2019, 03:31:37 PM »
Thank you, Achim!  I appreciate all the support :)


This is the first Saturday in some time that I’ve really gotten to play in my shop!  And I made some pretty good progress! Today I finished up the sides to the tender.  This involved cutting some edge support pieces for the sides and soldering them into place.  Kozo calls these “Side Corner Members.”

Before I get started on the update, I wanted to post one more shot of the formers I used for the sides.  I’d added some ‘registration post’ (i.e. little nails) to help align things between annealing. There were some questions about that so I took one more picture to show just the wood formers, without the copper side plate in the middle.  The brads are friction fit into one side of the former, and the other side just has clearance holes, as did the side plate that I was forming.  Hope this helps.



In my last update, I’d just finished shaping the sides and cutting the one-piece the middle to make the left and right sides.  So, my next step was to clean up the cut and make sure the sides were of equal size.  I did that mainly on the 4x36 belt sander.  (This is a staged shot.  I generally don’t steady my hand on the belt while it's moving.  That would hurt!)


Then I spent some time cleaning up the sides to get rid of the soot and heating discoloration.



Chapter 5.3 – Side Corner Members

Next up was to make the Side Corner Members.  These are 5/16” square brass bars that will fit along the base of each side. They provide rigidity and a way to attach the sides to the base.

After cutting the two pieces, I clamped both of them in the mill and squared up the ends, getting them to the correct length.  I realize that isn’t ideal, to have the bars sticking out from the vise, but I wanted to be able to use the DRO to measure the length.  So I just took light cuts, very gently and it seemed to work out OK.


Next, I rounded the ends to fit the inside contour of the sides. This is just a standard 1/4" round-over wood router bit. It worked fine on the brass.


Then drilled the mounting holes in the corner pieces.  I did them both at the same time, for simplicity.


And then tapped them 3-48.


Rotated the corner pieces 90 degrees and drilled holes for some 1-72 screws. These will be used to hold the pieces to the side for soldering.


I fit each corner piece to the corresponding side. Using clamps to hold the pieces together in the right place, I drilled through the 1-72 holes into the copper sides.


Then I opened all those holes up to be a clearance fit for #1 screws.


And finally, I tapped the holes in the side corner members.


Now, I was ready to solder the sides pieces up.
I cleaned up the solder joint area and prepped it for soldering with flux and lengths of solder.  It parts held together with five 1-72 brass screws.  Now, this is soft solder.  The point of these joints is to make the tank sides watertight (and to hold the parts together of course :)).


After soldering:


And here are the two sides, soldered and cleaned up.  I couldn’t fit these large pieces into my pickling container :(.  I sloshed the pickling juice around on the parts, then washed them up with soap, and I guess I’m OK.  But there was no ‘soak’ like I usually do.  I’m going to have to find a larger container to use I guess…


And finally, here’s a family shot with the sides mounted:




Thanks for looking in!
Kim

Offline Dave Otto

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #464 on: October 13, 2019, 04:40:40 PM »
Nice work Kim!
It's starting to take shape now.

Dave