Author Topic: Pennsylvania A3 Switcher (Kozo)  (Read 29821 times)

Offline cnr6400

  • Full Member
  • ****
  • Posts: 394
Re: Pennsylvania A3 Switcher (Kozo)
« Reply #120 on: December 24, 2018, 04:49:07 PM »
Chris, you may need to consider a better lock on the spirit locker for next Christmas.......

Ish power;luf schtuf tha elf eg no^&g..... :insane:

Offline Kim

  • Global Moderator
  • Full Member
  • *****
  • Posts: 3755
  • Portland, Oregon, USA
Re: Pennsylvania A3 Switcher (Kozo)
« Reply #121 on: December 24, 2018, 06:07:41 PM »
Thanks CNR, that's a very clever idea!  That would get them lined up and solve the vertical alignment and rotational issues.
Is there a standard way to get the letters spaced evenly?  Or do you just eyeball it?

Thank you!
Kim

Offline Ye-Ole Steam Dude

  • Full Member
  • ****
  • Posts: 1535
  • Deep East Texas on Sam Rayburn Lake
Re: Pennsylvania A3 Switcher (Kozo)
« Reply #122 on: December 24, 2018, 06:52:57 PM »
Hello Kim,

Your new "layout" by chapter is really neat and should be extremely helpful to all those who build a like unit.

Happy Holidays,
Thomas

Offline cnr6400

  • Full Member
  • ****
  • Posts: 394
Re: Pennsylvania A3 Switcher (Kozo)
« Reply #123 on: December 24, 2018, 07:52:36 PM »
Thanks CNR, that's a very clever idea!  That would get them lined up and solve the vertical alignment and rotational issues.
Is there a standard way to get the letters spaced evenly?  Or do you just eyeball it?

Thank you!
Kim

Hi Kim, I can't take any credit for the idea - saw it done many years ago by the old-timer master mould and diemakers I worked with. Just passing it along. As to spacing, you can't get the letters closer together than the punch centre to centre distance (without altering the punches), but you can of course add spacers between punches. When using punches in a frame, one set of letters/numbers could be punched after the frame is located to a datum, say a mill vise stop, by a spacer made from scrap, or a gauge block stack. Then if you want a second set of letters / numbers punched a known distance away, do another spacer or gauge block stack the desired distance away from the datum, less the frame thicknesses. Five piece frames with 3 crossmembers can be made to punch two rows of letters/numbers, more crossmembers could in theory be added to the frame for more rows. Again though the more punches in the frame the more chances for one to jump out of position while using the hammer. Good luck and have fun letter punching!

I'm off to my workshop now to see how bad my own shop elves / tool hiders have broken up the joint - they picked up some bad egg nog habits from Crueby's elves I think..... :DrinkPint:

Offline Kim

  • Global Moderator
  • Full Member
  • *****
  • Posts: 3755
  • Portland, Oregon, USA
Re: Pennsylvania A3 Switcher (Kozo)
« Reply #124 on: December 24, 2018, 08:39:13 PM »
Thanks Thomas!

And thanks for the reply, crn.  I'll have to think on the horizontal spacing a bit.  But getting things aligned vertically would be a big improvement for me! :)

Kim

Offline Steve17

  • Full Member
  • ****
  • Posts: 48
Re: Pennsylvania A3 Switcher (Kozo)
« Reply #125 on: December 26, 2018, 05:27:15 PM »
Hi Kim,
I think I will follow your lead and work in chapters also painting as you go. After three years on and off I just have a collection of bits and pieces for my 5" gauge Kozo climax's.
Steve.

Offline Kim

  • Global Moderator
  • Full Member
  • *****
  • Posts: 3755
  • Portland, Oregon, USA
Re: Pennsylvania A3 Switcher (Kozo)
« Reply #126 on: December 27, 2018, 07:37:08 AM »
Sounds great Steve, can't wait to see where you are on you build!
Now I'll have to get the Climax book.  That and the New Shay are the two I'm missing from the set.

So, are you scaling Kozo's plans? I thought all Kozo's locomotives were 3.5" scale.

Kim

Offline Steve17

  • Full Member
  • ****
  • Posts: 48
Re: Pennsylvania A3 Switcher (Kozo)
« Reply #127 on: December 27, 2018, 10:35:00 AM »
Hi Kim,
It's a strange world I'm happy playing with CNC but I have a phone that's a lot smarter than me and I generally run a mile from computers. I'll have to work out how to load pictures and start another thread.
The only Kozo book I haven't got is the old Shay, but the one I would like is the K27 when it happens. That would make a good size loco in 5".

Offline Steve17

  • Full Member
  • ****
  • Posts: 48
Re: Pennsylvania A3 Switcher (Kozo)
« Reply #128 on: December 27, 2018, 10:39:58 AM »
Forgot to mention, yes I am scaling up to 5". Some of the components need a bit if refinement I think and you have to keep an eye on fixings and tube sizes but other than that it should work out.

Steve.

Offline Kim

  • Global Moderator
  • Full Member
  • *****
  • Posts: 3755
  • Portland, Oregon, USA
Re: Pennsylvania A3 Switcher (Kozo)
« Reply #129 on: December 27, 2018, 06:56:19 PM »
Thanks Steve,
Well, I'd love to see what you're doing. If you wanna try, there are a bunch of us here willing to help you figure out how to post pictures to the forum.  It's not that difficult, I've figured it out after all  :Lol:
Kim

Offline Kim

  • Global Moderator
  • Full Member
  • *****
  • Posts: 3755
  • Portland, Oregon, USA
Re: Pennsylvania A3 Switcher (Kozo)
« Reply #130 on: December 28, 2018, 06:06:14 AM »
As I mentioned in another thread, Santa was generous this year and stuffed a nice new vise down the chimney for me!  Here’s a picture of the bench all prepped, with mounting holes drilled:


And here’s the finished product.  I’m pleased with the new vise.  Much more substantial than my old, rather rickety vise.


OK, continuing on with the Journal Boxes.  This work was done in several segments out in the shop, but I’m combining it all into one update to get me up to real time.

This is going to be a multi-step operation. So, I marked each of the Journal Box blanks on one end so that every time I swapped that piece into the mill vise, it would be oriented the same way.  With that, I setup the stop and positioned the mill to spot and drill a 3/8” hole for the journal bearing.


Then I setup the boring head to produce a 0.393” hole, and bored all the holes to that size.


Here’s the shot to this point (that was one shop session).


After getting the vise anchored to the bench today, I did some experiments to work out how to cut a 5/16” slot JUST right.  I used two passes of a 1/4" end mill.  Apparently, the 5/16” end mill doesn’t quite make a 5/16” slot.  And doing it in two passes of the 1/4" felt safer.  Anyway, after I got that worked out, it was just a matter of doing it 16 time; once on the top and once on the bottom of each Journal Box.


Here’s all the Journal Boxes at the end of play time today.  I started with nine so that I had one spare.  Well, I burnt that spare today on the 5/16” slotting operation.  I missed one of them and dialed in the incorrect number. (The one I boogered up is on the far right).


I'd considered leaving the mill setup for one pass and cycling through all 16 positions, resulting in 32 part moves. But instead, I chose to only have 16 part insertions/removals and position the mill using the DRO each time.  I thought that would be less errorprone.  Guess I was wrong. Ah well. At least I had a spare, right?

Still several more steps on the Journal Boxes, so I'll be tackling those tomorrow.

Thanks for stopping by!
Kim

Offline Roger B

  • Global Moderator
  • Full Member
  • *****
  • Posts: 4087
  • Switzerland
Re: Pennsylvania A3 Switcher (Kozo)
« Reply #131 on: December 28, 2018, 08:15:24 AM »
Still following along and enjoying :ThumbsUp:  :ThumbsUp:  :wine1: A good start on chapter 3  :praise2:
Best regards

Roger

Offline Steve17

  • Full Member
  • ****
  • Posts: 48
Re: Pennsylvania A3 Switcher (Kozo)
« Reply #132 on: December 28, 2018, 10:20:17 AM »
You are making really good progress with your axel boxes. It doesn't matter how many spares I make I'll always trash them.  :popcorn:

Steve.

Offline Kim

  • Global Moderator
  • Full Member
  • *****
  • Posts: 3755
  • Portland, Oregon, USA
Re: Pennsylvania A3 Switcher (Kozo)
« Reply #133 on: December 28, 2018, 06:12:48 PM »
Thanks Roger and Steve,
Appreciate the commiseration :)
Kim

Offline Kim

  • Global Moderator
  • Full Member
  • *****
  • Posts: 3755
  • Portland, Oregon, USA
Re: Pennsylvania A3 Switcher (Kozo)
« Reply #134 on: December 29, 2018, 07:16:07 PM »
Continuing on with the Journal Boxes:

Next step was to spot, drill and tap 32 holes.  The holes are the same on the top and bottom of the box.  Rather than move the mill head each side, I decided to do twice as many part insertions.  So, my order of operations was:
  • Spot one hole, flip the part and spot again. – do this 8 times (16 insertions for 16 spots)
  • Reposition the mill head to the other position and do the whole operation again (16 more part insertions for 16 more spots).
Here’s part way through the first step.


Next, was to drill 32 holes, 3/16” deep.  I did basically the same thing here – 32 drilling operations, one per insertion (1 each side of 16 sides (8 boxes), reposition mill and do it again).

This was the first time I've used the depth stop on the Z-axis.  It actually worked WAY better than I'd thought it would.  I'd had not expected to rely on the stop, but to just have it keep me from making really gross errors. But I was able to set it to the thousandth, and it stayed there, VERY consistent. That made this drilling operation, repetitive as it was, much less onerous!

Finally, was the tapping.  Same process.  I hand tapped, but used the mill to keep the tap straight.


All totaled, there were 96 part insertions to complete this step! And each one registered quite well.  I was quite pleased with that.

With all holes drilled and tapped, the final step was to put the fancy bevel cuts on the boxes.  That’s where those fancy angle jigs I made come in :)

I first did the 45o section.  This was 3/16” on each side, so I calculated that I needed to go down 0.132” from the tip. It came out just right! :) Did 8 of these.


And finally, the 3/10 angled section.  I calculated the depth to be 0.1796” for this.  And it also worked out just right.


Here’s the 8 Journal Boxes now complete:

They need a bit of clean-up to help get rid of the mill marks, but they look pretty good!
Kim