12" working railroad

Discuss park gauge trains and large scale miniature railways having track gauges from 8" to 24" gauge and designed at scales of 2" to the foot or greater - whether modeled for personal use, or purpose built for amusement park operation or private railroading.

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Topics may include: antique park gauge train restoration, preservation, and history; building new grand scale equipment from scratch; large scale miniature railway construction, maintenance, and safe operation; fallen flags; track, gauge, and equipment standards; grand scale vendor offerings; and, compiling an on-line motive power roster.
rkcarguy
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Joined: Tue Aug 22, 2017 10:33 am
Location: Wa State

Re: 12" working railroad

Post by rkcarguy »

My phone actually takes very good pictures, like 16mp. One of it's few positives. But that's the problem the files are far too large then. My old droid had an option to change the size/quality and I could also hook it up to my computer and DL pics to it. This one doesn't, cell phone company must want to make us pay more for data by having 4.5 meg pictures that I have to send....scam artists :x I can open them in "paint" at work and resize so they fit. If I'm working through my dumb phone on the weekend though, I can post them to FB and recopy them here. Easy enough.
Not a whole lot gained this weekend, I purchased a 12 volt air compressor, the 150 PSI one from harbor freight, and some brass pipe fittings so I have it all on hand when I start laying out my chassis.
rkcarguy
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Joined: Tue Aug 22, 2017 10:33 am
Location: Wa State

Re: 12" working railroad

Post by rkcarguy »

https://imageshack.us/user/rkcarguy

Imageshack is working again. I have ALOT of pictures in there if you'd like to have a look. This is a paid account, so no pop up ads or anything.
rkcarguy
Posts: 1730
Joined: Tue Aug 22, 2017 10:33 am
Location: Wa State

Re: 12" working railroad

Post by rkcarguy »

truck sides.jpg
Freight truck drawing in CAD. These accept the UCF-205-16 4-bolt pillow blocks for 1" axles. Wish they looked more realistic, but it's function over form for me. Link to bearings below.

https://www.amazon.com/dp/B01MA6M8V7?m= ... etail_page

My thought is, the horse-shoe shaped plates would be welded onto 1x2 steel, sandwiching each side of the truck sides with some .006" shim stock clamped between. I'd install a grease fitting and grind some grease grooves so that this sliding area was well lubricated.
The hole where the springs and 1x2 would pass through, is .030" over width, which combined with the radius corners on either a rectangle tube or hot roll bar, will allow the truck to pivot some front to back.
Not shown, I'm assuming I'll need some kind of grooved spring perch that will support the bottom of the springs. Easy enough.

These would be 3/8" plate I'm looking to have laser cut. Thoughts? Critics?
Kimball McGinley
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Joined: Wed May 31, 2006 2:13 pm
Location: Laguna Niguel CA

Re: 12" working railroad

Post by Kimball McGinley »

I'll share my first experience with laser-cut 1/2" steel parts. The parts were nice and very reasonable, but they started the cut on the part outline, which blew a big divot out on each piece. I'll probably fill them with "Bondo" or such.

If I had known that, I would have paid more to have them start the cut off the part about a 1/4" or so, then sweep it into the part profile. The sweep could have then been cut away (I think) at the very end of the part cut.

I am not sure how to model that, but I would think it might be a programming option.

Just to be careful, I had them cut lefts and rights, although they told me the kerf would not be tapered more than a few thousandths.

Kimball
rkcarguy
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Joined: Tue Aug 22, 2017 10:33 am
Location: Wa State

Re: 12" working railroad

Post by rkcarguy »

bettendorf.jpg
Yes that is a programming thing that they should be doing, it's a pretty simple thing to pierce the steel away from the part, then sweep into the edge of the part profile. I draw these for some vendors, others have a program that adds it to the "path" automatically.
I've been playing with the shape a lot, getting some better looking results now.
As for right and left sides, no reason to do that with laser as long as your parts are symmetrical, as camber is next to nothing.
rkcarguy
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Joined: Tue Aug 22, 2017 10:33 am
Location: Wa State

Re: 12" working railroad

Post by rkcarguy »

turnout.jpg
I drew up a turnout last night. This has a 40' radius in the curved portion, then I straightened it out as soon as I could so the pivot point is further from the frog than is usual. The reason for this, is that when you have a curve one way, you need to have a straight portion following it at least as long as your longest locomotive/rolling stock before it curves the other way, otherwise the cars can "crab" and bind up at the couplers. (Learned the hard way in HO scale).
I'll have the "arrowhead" portion of the frog laser cut from plate, the rest will be groovy track style flat bars, and flat bars welded to plate for the sliding point rails.
I've decided I'm going to have a plate jig laser cut such that I can screw it down to an assembly of ties and router around it to give me all the grooves for my rails. Using plate will allow me to flip it over for RH or LH turnouts and router cutting all the rail grooves at once will allow me to rapidly produce turnouts.
The turnout ends very shortly after the frog, I did this to keep the overall length at 10' for material and handling purposes. I will make a special piece of track to attach to the diverging route that has the proper length straight portion then a curve to bring the line back parallel with the main line.
rkcarguy
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Joined: Tue Aug 22, 2017 10:33 am
Location: Wa State

Re: 12" working railroad

Post by rkcarguy »

I made a good score during lunch today, I dropped into the local metal vendor near work, and they had a chunk of this very fine expanded metal mesh in aluminum that was all bent up from shipping. I want to say it's .035" thick and has 5/16" long expanded metal "diamonds" in it, it's the smallest expanded metal made and it's perfect for the grille on the S12. They sheared a usable chunk from it and sold it to me for $10:)
I also calculated the "spread" on my hood lump, and then 1/8" at a time, broke a nice radius on either end the piece that will make the headlight "lump" on the hood of the S12. I've got a little trimming to do, and then I can finally put that together this weekend and have the hardest part of the body behind me.
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NP317
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Location: Northern Oregon, USA

Re: 12" working railroad

Post by NP317 »

Looking forward to seeing photos of your progress.
Thanks for sharing.
~RN
rkcarguy
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Joined: Tue Aug 22, 2017 10:33 am
Location: Wa State

Re: 12" working railroad

Post by rkcarguy »

loco.jpg
lump.jpg
lump2.jpg
mesh.jpg
rkcarguy
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Joined: Tue Aug 22, 2017 10:33 am
Location: Wa State

Re: 12" working railroad

Post by rkcarguy »

Next I've got to cut, notch, and taper the back of the headlight assembly to fit....
rkcarguy
Posts: 1730
Joined: Tue Aug 22, 2017 10:33 am
Location: Wa State

Re: 12" working railroad

Post by rkcarguy »

I was looking at the S12 pictures SMS sent me. The pieces of the locomotive body over the engine are actually a formed L-shape plate that starts at the top of the access doors, and wrap around on to the top of the hood, attached over the other plate work. This is a bonus, because these contain 95% of the louvers. If I can figure out a way to cut/form so many louvers these could then be formed and riveted over the current body.
rkcarguy
Posts: 1730
Joined: Tue Aug 22, 2017 10:33 am
Location: Wa State

Re: 12" working railroad

Post by rkcarguy »

AAR.jpg
Did an AAR truck drawing last night for my locomotive.
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