Big Train James's US Outline Workbench - sw1500 Kitbash

Big Train James

Western Thunderer
Huh. Never noticed that before. I'm guessing that most of my experience has been with tanks similar to the go40 variety in Mick's pictures.

I think mine will stay smooth :cool:.
 

Big Train James

Western Thunderer
Mick, in that last shot above, at the far left edge just below the yellow stripe, is part of the jacking pad. I don't suppose you have any other good close shots of the pads that I could use to work up a 3d model? I've got a handful already but I'm missing info about the top of the pad where it welds to the bolster gusset. I'm working on them for gp38-2's but I think they are the same (or essentially) for the gp40's as well.

Much appreciated if you have photos, no worries if not.
 

mickoo

Western Thunderer
James,

For your work.

GP38
GP38_3449.JPG

GP40
GP40_1951.JPG GP40_2024.JPG GP40_2025.JPG

GP60
GP60_7497.JPG GP60_8936.JPG GP60_8938.JPG

SD40

SD40_0871.JPG SD40_2355.JPG

SD70M

SD70_2203.JPG SD70_2294.JPG SD70_2301.JPG

And if you wish to do a 'real' engine, mind SD70s are pretty hot.

ES44AH
ES44AH_3209.JPG

Some of the lower angles are a bit burnt out as I was after the detail underneath, so if there's one you need reworking, let me know and I'll pull it from the archives and run it through some editing to get the detail you want.

Enjoy.

MD
 
Frame and fuel tank machining - Update 01/31/17

Big Train James

Western Thunderer
Time for a brief update on progress on the frame parts. I only see my machinist friend on Monday nights when we gather to run some HO trains. It's exciting to see progress, but frustrating to know that I have to wait another week to see more.

The fuel tank has been spliced. The only remaining machine work here is to drill new holes for the two fuel fillers and the fuel gauge. All locating dimensions have been identified, so I expect this to be done by next week.

fuel tank-splice.jpg

The fuel filler tubes will match the red capped pipe at the top right in the following photo, except they are much shorter in length. On the sw1500, the pipes enter the tank right at the corner where the top of the tank starts to bend down, instead of reaching further back on the tank. The air reservoirs are clear of the fueling appurtenances on longer tanks, but exceed the full length of the switcher tanks, so they need to be accounted for. I will either use the existing Atlas filler tubes, or switch to a third party detail, depending on quality and accuracy of the parts.

fuel gauge.jpg

The fuel gauge is recessed in the side of the tank, as seen in the lower middle left above. This photo is of an sd40-2 tank. The sw1500 tank recess is similar, but this one appears to be a flat bottomed cylindrical recess while the sw1500 recess appears to be more of a dish. The original plan was to use a 3/16" ball end mill to .050" depth to create an 8" scale dimple in the fuel tank. I would then drop an etched disc representing the gauge into the recess creating the flat bottom. At issue with this method is achieving the circular lip that protrudes just past the surface of the tank side in any sort of effective manner.

The new ideas involve drilling all the way through the tank wall, and then milling the dimple in the end of a piece of round bar stock, and either turning the O.D. to achieve the lip (not sure that's possible without the material failing) or more likely now dimpling the end of an appropriately sized rod which can then telescope inside a corresponding piece of tube. The nice thing about the idea of turning the piece from solid rod is that a collar could be left on the end inside the tank, but that's not any kind of deal breaker. Either way, the protruding lip can be filed to match the curvature of the fuel tank if necessary, although I'm currently unclear whether whether that occurs on the prototype.

Working on the front end of the frame first, the cuts have been made and the resulting pieces have been squared and finished to the proper lengths.

frame splice-001.jpg

The ¼" x ¼" bars for the splices have been cut to length and one end shaped to match the fillet in the front corners of the frame. Next up will be drilling and tapping. The plan is to have two screws on each outside end of the splice, and either two or three screws in between the two cuts, depending on space. The flange we are attaching the splice plate to has an unnecessary notch at the bolster so there may not be enough area to locate the third screw.

frame splice-002.jpg

I would have preferred to use either 1/8" x 1/4" or 3/16" x 1/4" bar for the splice plates, but this will have to do. It's fine, as the splice plate is still hidden behind the frame rail. Screws will be countersunk flat heads similar to those used in the fuel tank splice plate.

I'm looking forward to next week as I expect at least this end of the frame to be finished. One consideration for the future will be how visible the splice lines are on the top side of the walkways, since they have the safety tread cast into them. If necessary, I'll try for an etched tread plate overlay from the thinnest possible material to neaten everything up.

Jim
 
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mickoo

Western Thunderer
James,

I think you're over working the tank gauge recess, lets say depth of gauge from front face is 5mm and hole is 10mm dia.

First drill tank side with 10mm dia drill but only 6mm deep or probably right through tank would be better.

Next obtain some 10mm brass thin wall tube and cut a slice 5mm long off, solder a blank to one end and round off so it matches the tube profile and make a sort of brass cup, insert cup from rear or front of tank which ever your preference until front edge of tube forms the required lip.

Etch gauge, drop of Loctite 480 on the back, drop in and sit back and admire your work.

I don't think you'll see the dished rear face so wouldn't sweat it, but if you must then do as you suggest with the ball ended cutter to make the recess and then simply slide the brass tube in afterward and trim to the correct length.

If you think about the real thing, it's nothing more than a hole with a stock piece of tube welded in and a blanking plate attached to the rear, no idea why it might be dished as dished or domed ends are usually only used in applications where the contents are pressurized.

Here's some close ups of a tank recess on a GP40 that might help.
IMG_1945.JPG


IMG_1947.JPG


MD
 
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Big Train James

Western Thunderer
I don't doubt that you are right about the over working/ over thinking aspect. It may be evident by now that I have to deal with that tendency frequently. Especially working in 3d cad where you can make things as perfect as you like since you can zoom in to view them and the practical constraints of the real world don't apply :oops::(.

That being said, at the end of post #114 on the previous page is a photo of the gauge in an sw1500 tank, and for all I can see it appears dished to me. But then I'm the same person that never noticed the small bend segments in the tanks in the first place, so my perception could resonably be called into question :eek:.

I'll sort it out soon enough.
 

mickoo

Western Thunderer
James,

You carry on my good man, it's all food for thought and discussion :thumbs:

Shame I cannot pop down the road and check these details for y'all, however, having done several detail photo shoots of class 66 (shrink dried SD50) I wondered if anything carried over in the EMD production ideals.

The tank is the same faceted bend construction.
66 717_Detail 20.jpg

And the fuel gauge plus housing bears a close resemblance to US fitted types.
66 717_Detail 21.jpg

MD
 

jonte

Western Thunderer
James,

You carry on my good man, it's all food for thought and discussion :thumbs:

Shame I cannot pop down the road and check these details for y'all, however, having done several detail photo shoots of class 66 (shrink dried SD50) I wondered if anything carried over in the EMD production ideals.

The tank is the same faceted bend construction.
View attachment 63531

And the fuel gauge plus housing bears a close resemblance to US fitted types.
View attachment 63532

MD

Thanks for the photos, and tips, mickoo!

A job I need to do a.s.a.p. on the fuel tank of my GP38-2. I've also opted for the shortened brass tube idea although hadn't considered the blank end bit. Good idea.
 
Frame machining work completed

Big Train James

Western Thunderer
Time for a quick update on this project. I've got my frame back from my fellow modeler/retired machinist. Three major points of emphasis for the work: shorten the frame, modify the fuel tank, and add new and improved air reservoirs.

First up, the frame. I came to realize after the fact that the frame would need to be shortened in three locations. The bolster spacing needed to be reduced by 2'-2", which actually required two cuts and splices. And I needed to remove 10.5" between each bolster and pilot. Two cuts were needed for the bolster to bolster spacing so as to not disturb the motor mount spacing.
Front:sw1500 frame-022.jpg

Rear:sw1500 frame-024.jpg

The bottom side of the frame was cleaned up on the mill to remove all undesirable protrusions like ejector pins, mounting bosses, and the fuel tank diecast "core". 1/4" x 1/4" brass bar stock was clamped together with the frame, and then drilled and tapped for 3-48 flat head screws. There is a nice flat flange all around the frame that is quite ideal for mounting the splice bars.

Front:sw1500 frame-018.jpg

Rear:sw1500 frame-017.jpg

Fuel tank core:sw1500 frame-013.jpg

The model has a diecast finished tank cover that fits over and screws to the frame, covering the bottom of the motor. I was satisfied with the profile of the finish tank casting, so it just needed to be shortened to 5'-6" in length for the sw1500. Both ends were cut off with a piercing saw and then machined. I didn't bother to keep the ends and take the cut out of the middle as I was going to add a representation of the end sheets and didn't trust a laminate to the diecast end for durability. I will make a proper end sheet profile of styrene, and then laminate that to a .060" styrene "key" that fits inside the end of the tank, with epoxy to hold it in place. At the same time, the tank was split down the middle lenthwise to remove a scale 4" from the width. The tank was wider than the frame, where their faces should line up. It's one of those things that is tiny but would easily be perceived by the eye. Everything was clamped and joined with a splice plate and countersunk flat head screws.
sw1500 frame-020.jpg

The tank has two holes at the top rear corners to mount fuel filler pipes, and a hole in the engineer's side for fitting a 3/16" brass tube for the recessed fuel gauge. These can be seen in the shot above with the fuel tank core.

The 15" diameter air reservoirs were turned to the proper profile from 5/16" brass rod. A groove was turned at each end and received a recessed .020" phosphor bronze wire soldered in place to represent the weld bead. The ends were also drilled out to receive the end of the air lines once they are fabricated.
sw1500 frame-015.jpg

The next question was how to mount the fuel tank and air reservoirs. The fuel tank would be simple enough, with a bracket fitted to the splice plate which could mount to the inside of the frame rails. The air reservoirs were another matter. I would have soldered them to the frame if it weren't diecast. There was a thought about drilling and tapping down through the walkway into the tops of the tanks. This would have been ok aesthetically if I went ahead with the idea of a new thin etched walkway sheet to cover the new joints in the frame. But the tanks would have been permanently affixed then. The solution was to drill and tap the backside of the air reservoirs rather than the tops. Screws would then be inserted through the frame and fuel tank bracket from the inside of the frame. The whole assembly can be unscrewed and dropped out for painting or detailing work. I don't have a great picture of this as it's mostly hidden, but parts of the arrangement can be seen in previous photos.

There are a few tweaks to be made with the height of the fuel tank mounting, but otherwise I'm quite happy with the results. Next up will be to finish the ends of the fuel tank and detail the underframe with proper piping, cabling, jack pads, lights, air dryer, and so on. I have made some progress on the shell above, but didn't want to go too far until I had the frame so that I could get the proper fit.
sw1500 frame-003.jpg sw1500 frame-004.jpg sw1500 frame-005.jpg sw1500 frame-010.jpg

So much still to do...everywhere. But it's not a race I suppose. I'm hoping that continuous progress will keep my mojo engaged, as at times I've suffered from the same malaise that Jordan and many others have recounted.

All for now. Leaving for a week in Canada on Thursday morning, after which I hope to make steady progress on all fronts.
 
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mickoo

Western Thunderer
Looking good, the machine work is impressive, neat and workman like and those tanks look the business (I think you would say 'kewl man' in the US ;))

I do hope to drag my MP15 out next week and look at what's required to progress it, certainly the front end and radiator cores need addressing and then look at railroad specifics, I've still not decided on either CSX, NS or UP as yet.

MD
 

Pugsley

Western Thunderer
That's looking superb - I can see that there's some real high quality workmanship gone into that.
 

Big Train James

Western Thunderer
Thanks. In the future, I'll try and find a local machine shop that does short run custom work. I'd like to get the air reservoirs done on a CNC lathe or screw machine as I could use several sets, and the fuel tank cut on a wire edm machine. I'd also strongly consider doing the frame from scratch rather than modifying a diecast version. There was quite a bit of effort in cleaning this one up and resizing it. It seemed like a simple and good idea at the time...:oops:. A proper frame done of brass or nickel silver would work better for assembly and attaching all the bits and bobs to.

The radiator etch is perpetually on my mind, as well as perpetually in the works. I believe I will go ahead and remove everything from the front of the loco and redo it all from etch. If nothing else, the opening in the nose isn't square, when I believe it should be, on account of Atlas needing to clear the threaded insert along the bottom edge of the opening where the shell screws to the frame. An etched version will undoubtedly look better as well.
 
Bogie sideframe test prints

Big Train James

Western Thunderer
Well, it's been a long time since I added anything to this thread. There's been work going on in the background, but as usual progress has been slow due to the usual fluctuations in mojo, a lot of non-model related tasks and activities, and various other distractions.

Lot's of time has been spent on 3d cad for various parts of the loco that I would like to improve upon, namely in the area of the bogie sideframes and cooling system details. I've gotten test prints (from Shapeways in this instance) along the way, and the results have informed decisions on how to proceed.

Some pictures are in order. I'll start with the sideframes first. I'll need to split things up into additional posts as there are more than 15 pictures. Apologies as the prints look a bit rough here as I didn't clean the parts prior to priming, as I didn't want to damage anything. They are quite fragile in places. The result is that the primer hasn't ever cured or adhered to the model properly, so it is still tacky and has collected some cat hair, as well as getting scratched/rubbed off in many places.

I'll start with a couple of shots of the original Atlas Flexicoil sideframes. Most of the improvements should be readily apparent when comparing their version with mine. I'm confident that mine is essentially dead nuts accurate. I had good information to work with which always helps. About the only concessions involved were a result of making the model printable/castable, and for attachment to the Atlas gearbox.
wt-atlas flex-002.jpg wt-atlas flex-001.jpg
wt-flex-001.jpg wt-flex-002.jpg wt-flex-003.jpg wt-flex-004.jpg wt-flex-005.jpg wt-flex-006.jpg wt-flex-007.jpg wt-flex-008.jpg
 

Big Train James

Western Thunderer
Batch #2.....
wt-flex-009.jpg wt-flex-010.jpg wt-flex-011.jpg wt-flex-012.jpg wt-flex-013.jpg wt-flex-014.jpg wt-flex-015.jpg wt-flex-016.jpg

This particular test print has no allowance for springing or equalization. My use will be as non-bearing sideframes attached to the gearbox only, so there's no need or point for suspension. Or course, I have the original model comprised of separate parts, so it would require only a small amount of work to print the frames without journals or springs, and separating the journals for use with small springs. The frame is hollow like the prototype, and has a cup above the journals for spring bearing.

Or course, this version also doesn't include the full bolster, as the gearbox takes its place. However, again, the bolster is already modeled and it wouldn't be a stretch to add the two large springs to allow suspension at both the journals and the bolster. Just like the real thing.

I'm pretty stoked about how the frames have turned out. Aside from the satisfaction of creating something in cad and then seeing it come to life, all the thought and consideration and diligence has yielded a mostly successful product. Mostly though I'm happy because in my opinion it's evident that the work to create an improved version of the sideframes has totally been worth the effort, especially when stacked up against the original Atlas version.

The print is pretty successful as well. Everything has rendered decently, and things will only improve when I have masters printed on a quality machine. I've had to reinforce a couple of weak spots where parts partially detached in the support removal process or in shipping. And I am going to adjust the spacing between the slack adjuster bars on either side of the wheels, as I think I could use some extra clearance there. As it is, I will almost certainly need to insulate the bars with CA and tissue paper, and probably shim the wheelsets to remove some of the side to side play.

One last picture of the sideframes. I spent a lot of time engineering the business side of things, figuring out how the frames would attach to the gearbox, and just as importantly, figuring out how I would pick up power and get it from the bogies to the motor. This next shot is a cad capture as I don't have anything fabricated yet. It will utilize a phosphor bronze wiper, a terminal lug, nylon screws, and a printed plastic insert to mount the wiper to the gearbox and insulate the pickup at the same time.
sw1500 flex-008.JPG sw1500 flex-009.JPG
 
Radiator cores and front hood

Big Train James

Western Thunderer
One of the other areas of the Atlas shell that could use improvement involved the cooling system details, including the fan and grille on the front of the loco as well as the radiator cores and corresponding grille at top front area of the hood. The stock Atlas shell is rendered with closed shutters at the front of the loco, and a boxy representation of the radiator cores that is wrong in shape and completely devoid of any of the detail or character of the prototype. Combined with etched metal grilles that are a touch heavy and generally inaccurate, and the overall effect is fairly underwhelming.

In addition to improving the radiator details, I wanted to represent a Southern Pacific prototype, which is well known for utilizing unusual lighting packages on the nose and above the cab, and for the high mounted numberboard housing above the windshields on the front of the cab. Lastly, I wanted to improve the sand filler hatches, adding depth and detail, and revise some of the sheet metal around the nose area.

The following images are copyrighted as noted, and used here for reference only. The first picture illustrates the original as-delivered light package. The second pic shows the revised arrangement later in life, with two of the lights removed and the class lights blanked out, which is what I will be modeling. The last photo shows the numberboard housing.

showimage.jpg showimage (2).jpg rs_mp15ac-x.jpg

First up are the radiator cores. The goal here was to capture as much of the detail as possible, including the nuts and bolts, headers, core frames, core mesh, and so on. One trick is to first decide which type of radiator core to model. Cores can have different frame styles, different mounting tabs, and different stiffening ribs on the sides. There are also three sizes of cores, in effect 1X, 2X, and 3X lengths. The radiator core compartment is the length of three small cores, plus the headers. Cores can be found in combinations, per side, of 3 short cores, 1 short and 1 medium core combined, or 1 single full length core. Often the two sides will have different core arrangements. It all depends on what the original unit was delivered with, and what components were used during shoppings. This really is a situation where proto photos of a specific unit would be useful, but they frequently aren't available. At some point, one must simply bite the bullet and choose a style. Again, the following photos are for reference only.

3 short cores:
39918540.Scan553.jpg

1 short and 1 medium core:
2536c_sp-sw1500-rob_sarberenyi.jpg

1 full length core:
BNSF 3404 2-7-2009 number.jpg

The best part is that I can find examples of SP locos with all three conditions. I went with the 1X+2X version for this model. Of course, I had to go ahead and do 3d cad for all three combinations, so I can always use a different style on a different model.

One of the other goals with the radiator core model was to have a screen representing the core mesh that would allow for sound to escape the shell. The idea is mount a shelf inside the shell, from nose to just in front of the cab, above the motor. The front part of the shelf would hold a Tang Band speaker facing upward, to fire through the radiator "screen". The back part of the shelf will hold a Loksound decoder. The original inspiration for this speaker arrangement came from a Bob Sobol post on the Appalachian & Ohio crew forum (a very nice O scale layout out in Colorado). Bob was going to use speaker fabric to hide the speaker on an Atlas sw8/9 model. I was concerned that after painting and weathering, the fabric might stiffen up and not be so "accoustically transparent". I plan to instead use an etched metal screen, ideally with an appropriate grid sizing to mimic the core mesh, and either paint it or blacken for color. In the photos to follow the test screen is from a Plano Models HO scale hopper walkway. I will go with the smallest commercially available mesh I can find, or have a piece custom etched.

wt-rad-001.jpg wt-rad-002.jpg

wt-rad-003.jpg wt-rad-004.jpg wt-rad-005.jpg wt-rad-006.jpg wt-rad-007.jpg wt-rad-008.jpg

In the last three photos, you can see the slots in the end to slide a piece of .008" mesh into the radiator frames. The narrow slots below are for tabs on the end closure piece to fit into. The mesh as shown is just a test, but I would definitely like for it to have smaller openings. The goal is to mask the speaker below, and I'm not sure that would happen as it stands. If I can't get something more suitable, I will consider layering a second piece of mesh below this one, ideally with the members offset so they obscure more of what is below.

A picture of the original Atlas part can be found back on page 2, post #38, of this thread. As with the bogie sideframes, there's no comparison between the two versions.
 
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