Author Topic: Pennsylvania A3 Switcher (Kozo)  (Read 3144 times)

Offline Steve17

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #90 on: November 24, 2018, 10:10:54 PM »
Looks so much better and 15 minutes well spent. As you said you can always change your mind.

Steve.

Offline Dave Otto

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #91 on: November 24, 2018, 10:57:20 PM »
That looks much better Kim.
It wouldn't take too long to skim the OD and re-cut the 10 degree tapers, then the proportions would be correct; but tucked up under the tender it probably won't matter either way.

Dave

Offline kvom

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #92 on: November 24, 2018, 11:18:16 PM »
I would try turning one to the correct angle and just see what it looks like. The only bit that would give the game away would be the thickness of the tyre.

Steve

Yes, this is another strong contender.  If I do this, the whole wheel will be 0.084" smaller than its supposed to be and the tender will sit 0.042" lower than designed.  That's almost 3/64".  Maybe not a big deal, but I'm not sure I will be happy.

Ah... decisions, decisions...
Kim

Just ignore it for now and finish the frame and trucks.  Then you can judge its appearance.

Offline Steamer5

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #93 on: November 25, 2018, 02:30:47 AM »
Hi Kim,
 Just catching up on progress. The wheels look fine, just like they have been in the shop for re- profiling in full size! A friend of mine purchased a loco of another club members estate & found all the wheels a different diameter.....UP Challanger & went down the turn all too the same size & tired the lot.
 If you decide to go down the tire route another option is to use heavy wall tube, say schedule 40 or maybe 80 or even more or get some laser or water cut plate.

Keep up the progress.

Cheers Kerrin
Get excited and make something!

Online Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #94 on: November 25, 2018, 06:17:33 AM »
Thank you everyone, really appreciate your thoughts on this!

Dave, you're right, I was thinking the same thing - it wouldn't take very long to bring the flanges down a tad and then it would look even better.  Besides, I'll have to clean up the flange tapers a bit anyway.   Have to get rid of that little flat spot on the flange that Bill was talking about :)

Thanks for all the encouragement and suggestions!
Kim

Offline 10KPete

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #95 on: November 25, 2018, 06:19:11 AM »
 :ThumbsUp: :ThumbsUp: :popcorn: :popcorn:

 :cheers:

Pete
Craftsman, Tinkerer, Curious Person.
Retired, finally!
SB 10K lathe, Benchmaster mill. And stuff.

Online Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #96 on: December 02, 2018, 03:25:58 PM »
Thanks Pete!


Back to the shop to tackle the wheels.

I’d decided to bring the flanges down a tad to make them more proportional to the slightly smaller wheel.  The basic dimensions that I used for my ‘resized wheels’ was 2 3/16” for the outside of the flanges (vs. the 2 1/4" in the plans) and for the max tread height, I went with 1.90”  (where the plans say 2 1/16”).  If you bother with the math, you can see that this comes out to the 0.042” (radius) that I will be off due to re-cutting the tread at 3o (from the  10o I mistakenly, initially used).


Here is the flange being brought down to its new size, after cutting the tread slow down to 3o:


After this, I re-tapered the flanges, both front and back.  Didn’t show pictures of that, since its identical to what I showed back in post #57 (http://www.modelenginemaker.com/index.php/topic,8552.msg188280.html#msg188280).  After filing the flange top round and polishing them up a bit, here are all 8 wheels in their final form:




It wasn’t all roses today. When was cutting down one of the flanges, I mis read the DRO and just cut WAY past my stop point making the flange noticeably short.  So, I cut one more blank and started from the beginning on another wheel. It probably took me a little over an hour, but I got it back to the same point as the others quickly enough. My only issue here was “Now that I’m making a fresh one, should I leave it as specified in the plans? Or should I ‘make’ it smaller to match all the others?”  In the end, I decided that I’d just make it match the other seven.  If I decide I need that extra 1/16”, I’ll just have to make 8 more wheels. But it was kind-of hard to make it ‘wrong’ intentionally!

And in the spirit of showing off my foibles, here’s a shot of my wheel reject bits:


The one on the right was just today with the over aggressively shortened flange.  The one on the left was several weeks back.  I mis-read the dial caliper.  It showed 0.675” for the size of the center hub, but I read it as 0.775”. You know how you can see the ‘7’ when you’re in the high-range of the 0.600’s? Well, that bit me and this was the result.

With that, I think I’m ready to start a new part!  And next up will be the axels for the tender.  Luckily, only four of those :)

Thanks for all your support!
Kim

Offline crueby

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #97 on: December 02, 2018, 03:31:29 PM »
Bottom line - nice stack of wheels!!

Offline b.lindsey

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #98 on: December 02, 2018, 03:59:44 PM »
Those should work just fine Kim. I like that the flanges are proportional again. Nice recovery  :ThumbsUp:

Bill

Offline Steve17

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #99 on: December 02, 2018, 04:15:43 PM »
Looking good :praise2: when I was an apprentice I was told the difference an amateur and a professional was how well they can get out of a situation. Well executed recovery.

Steve.

Online Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #100 on: December 02, 2018, 05:49:58 PM »
Thanks Chris, Bill, and Steve,

... when I was an apprentice I was told the difference an amateur and a professional was how well they can get out of a situation. Well executed recovery.
Well, then I guess I can emulate a professional as long as I have a large team of helpful coaches giving me tips and suggestions!  :ROFL:
Kim

Offline cnr6400

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #101 on: December 04, 2018, 04:34:33 AM »
Great looking wheels Kim. A very good start to your locomotive's tender!  Also a couple of skill - building 'recoveries' under your belt for drive wheels and wheels of other locomotives.....can't get that out of any book or Yoot Ube video.

Online Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #102 on: December 04, 2018, 05:14:07 AM »
Thanks CNR,
Yeah, the drivers... I'm excited/scared to get to those :)  I'm planning on fabricating them if I can.  Should be doable, but if I run into too much trouble, all it takes is some $$ and I can buy a set from Friends.  But I'm excited to give it a try (eventually - that's probably a couple years out yet, at my rate!)

Kim

Offline b.lindsey

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #103 on: December 04, 2018, 01:59:56 PM »
Now that the tender wheels are sorted out, what are you planning to tackle next Kim?

Bill

Online Kim

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Re: Pennsylvania A3 Switcher (Kozo)
« Reply #104 on: December 05, 2018, 05:09:29 AM »
Next will be the axles, then I'll be moving on to the truck assemblies, starting with the Journal Boxes. :)
Kim