RS-3 narrow gauge conversion

[Ray Dunakin]

In addition to installing a Revo receiver and Phoenix sound board, I'm also converting my Aristocraft 1/29th scale RS-3 into a freelanced 1/24th scale narrow gauge loco. For now I'm holding off on the electronics until I get the other modifications finished.

 

I started by widening the deck. To do this, I glued 1/4" square styrene strips to the edge of the frame, then topped them with 1/4" x .010" strips. I still need to cover the expanded deck with new non-skid treadplate:

 

 

 

 

Next I made the hoods slightly taller, by gluing 1/8" x 1/4" strips all along the base of the hood pieces. I also reduced the length of the short hood, in order to accommodate a larger cab:

 

 

 

 

I also removed the "bug-eye" classification lamps. Soon I will remove the existing grab irons, fill the holes, and replace them with new grab irons that will be larger and spaced more appropriately for the increased scale.

 

 

To make this look like a narrow gauge loco in 1/24th scale, it needs a new, bigger cab. I began scratch-building one out of .080" thick styrene. I cut the front and rear walls to shape, taped them together and carved out the windows. While doing the windows I also trimmed the curved edge a little more:

 

 

 

Here's how it will look on the loco:

 

 

 

That's all for now. I'll post more updates as I go.

 

[PJM20]

I'm glad to see you have started your project. I can't wait to see the end result! - Peter

[IRB Souther Engineer]

Are you going to modify the trucks or wheels?

[Ray Dunakin]

IRB Souther Engineer

Are you going to modify the trucks or wheels?

 

I won't be changing the wheels, but I do plan to improve the appearance of the trucks. I'd like to replace some of the cast-on details, for instance.

 

[Ray Dunakin]

I haven't been able to get much done this weekend. Too many interruptions, plus I wasted a lot of time trying out a technique that didn't work before settling on one that did. Anyway here's the latest update... 

 

I've been building up the frames around the windows on the front wall of the cab. There are two parts to these. The first is cut from a sheet of .010" thick styrene, then glued to the window. They overlap the inside edge of the window a little bit:

 

 

 

 

Next I glue down a thin styrene rod to form a sort of "bead" around the inner edge. This is really slow and tedious but adds a lot to the appearance:

 

 

 

 

Two windows done, six more to go! Then I do the side windows.

 

[Ray Dunakin]

I've made a little more progress...

 

Finished framing the windows on the front and rear walls of the cab, and glued the cab together. To create the arched roof, I glued in strips of styrene, then sanded down the angled edges:

 

 

 

It still wasn't rounded enough so I filled it in a bit with spot putty:

 

 

 

Then I topped it with .015" thick styrene sheet. Unfortunately that wrinkled a little in places, so I had to smooth it out with a little more spot putty. I also rounded all the corners, and started detailing the side of the cab:

 

 

 

In this photo you can see some of the detail on the side of the cab:

 

 

 

That's all for now, more to come!

 

[Ray Dunakin]

Today I've doing some detailing on the short hood. I replaced the original grab irons with new, slightly larger ones, spaced farther apart, as appropriate to the new larger scale. Most of the grabs are from Phil's Narrow Gauge, I just bent them a little to fit the corner positioning on the hood. I had to make the longer grabs myself. I used Phil's brass, nut/bolt pins to secure them:

 

 

 

I also carved off the molded door handles and replaced them with new handles made from brass rod:

 

 

 

I put some small details to the top of the hood. I also made the sand box fill hatch larger and added hinge and latch detail:

 

 

[dwbeckett]

Lookig Good, are you following a prototype or is this a freelance home RR shop built engine

Dave

[Ray Dunakin]

Well, it's sort of semi-freelanced. I haven't found a narrow gauge prototype that fits. I think they did make some RS-3's in narrow gauge for foreign use but they basically just moved the wheels closer together. Since I'm working backwards and trying to scale up a smaller scaled, standard gauge loco, I have to take some liberties. But I'm trying to retain the look of the RS-3, and I'm using photos of real RS-3's to figure out all the details.

 

 

[Ray Dunakin]

I finished putting the grab irons and door handles on the long hood. I also filled in the overly-wide panel lines and scribed new, thinner ones; and replaced a couple of molded-on pipes:

 

 

 

 

I scribed some lines into the smoke stack, and replaced the molded details:

 

 

 

One of the reference photos I found included a close up view of the horn, which inspired me to go nuts and add all the little details to the horns on my loco:

 

 

 

The sideframes of the trucks have a lot of molded on detail, including the brake cylinder. I'm cutting those off and making my own, completely 3-dimensional brake cylinders. I haven't finished that yet, but here's a pic showing how I'm altering the shape of the steel arch-thingy (pardon the technical terminology!) to more closely approximate the prototype. I used epoxy putty to fill out the shape. Since this piece must be able to move up and down, I just put a piece of wax paper between the two parts before adding the putty:

 

 

 

That's all for now, more later...

 

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[Ray Dunakin]

I finished making a master for the brake cylinders. It just needs a little touch up, and then I'll use it to make a silicone mold. I need eight cylinders, and I really don't want to make them all by hand, so casting is the most efficient way...

 

 

 

The grill over the radiator fan isn't totally accurate but it looks pretty good, so I want to keep it. Unfortunately the holes are much narrower on the back then on the outside, in fact they're barely open. So I'm carving them out, one by one, with the tip of an X-acto knife. Very tedious, so I can only stand to do a little of it at a time. I'm halfway finished so far:

 

 

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[PJM20]

You project is turning out nicely, I'm also glad you have the patience to even get half way with those holes, I would probably just throw against the wall... - Peter

[Ray Dunakin]

Today I made a mold of the brake cylinder master. Because of the complexity of the shape, a two-part mold was needed. I built a form out of styrene, and filled half of it with sulfur-free modeling clay. Then I pushed the master into the clay, and worked the clay in around it to make as clean an edge as possible. I pressed a few dimples into the clay to make "keys" that will keep the two halves aligned:

 

 

Next I poured in some silicone rubber mold compound. I use Smooth-On brand "Oomoo 30" because it's easy to use and doesn't require a precision scale. It mixes by volume, not weight, and is pretty/ forgiving. When this set, I pulled off the bottom of the form and removed the clay. Leaving the master in place, I then coated the face of the first layer of silicone with a very thin coat of vaseline as a release agent. I also used a spray on release from Michael's:

 

 

I poured in some more silicone, let it set, then removed the form and pulled the two halves apart. Then I started casting. The initial casting came out rough, which is typical. The rest came out better. I had also made a simple one-piece mold of another part that will be used on the side frames, and cast that too. Here's how they look after cleaning up the flash:

 

 

And here's one of the brake cylinder castings after being painted with a coat of primer. It's a little bit rough but not bad:

  

 

[Ray Dunakin]

A little more progress...

I finished casting all the brake cylinders and install four of them on the rear truck.   

The brake shoes on the original model are removable plastic pieces, and include a curved shape that is supposed to represent the sand line. As-is, these brakes look pretty anemic. So I reworked them, adding on new styrene bits to make the brake shoes a little larger and thicker, and also made the hardware stouter and more accurately shaped. (In silhouette, anyway. As on the original model, a lot of liberties have to be taken in this area.)  

I cut off the original sand lines and built new ones that are much more realistic looking. Here's a shot of two remodeled brake shoe assemblies next to one of the unmodified parts:

 

Here's a couple shots of the modified parts temporarily installed on the truck. You can also see how the brake cylinder castings fit into place: 

 

I still have to make four more brake shoes pieces, for the loco's front truck.

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[Greg Elmassian]

Quite a bit better looking Ray!

Excellent work as usual!

Greg

[Ray Dunakin]

Doh! 

 

Rather than making the four remaining brake shoe assemblies individually, I wanted to try molding and casting them.

 

I spent a considerable amount of time figuring out a way to make a two-piece mold of the brake shoe assemblies. This was not an easy task, because they are a fairly complex shape. Got the first half of the mold cast. Added some stuff to form the fill channels, then poured the second half of the mold. All of this was done piecemeal, between numerous interruptions, which also meant a lot of it was done in a rush. (You can probably guess where this is heading...)

 

Pulled the mold out of the form this evening and discovered the Big Mistake. I had forgotten to apply any kind of mold release between the two halves of the mold. So now I have one big block of (expensive) silicone rubber with two master brake assemblies buried somewhere in the middle.  

 

< sigh >

[dwbeckett]

Ray, maybe you should add that OOPS to my new post in General Dis, dumb things NOT to do Part 2

Dave ( sometimes you feel like a nut (Case) ).

 

[Ray Dunakin]

I got the parts out of the rubber but could not salvage the mold. The shapes were just too irregular. I'm currently in the midst of a second attempt at molding the parts.

 

[Ray Dunakin]

 

Finally have another update on this project...

 

First, here's how I made the mold for the brake shoe assemblies:

 

I was concerned about the sand lines, which seem to be in a position where they are likely to get banged up a bit in use. So I inserted brass rods into the mold prior to casting:

 

I made the brake rods from brass:

 

I used short sections of rectangular brass tube to make the clevis on the brake rods. First I grind off one side of the tube, then cut off the short sections using a Dremel and cutoff wheel:

 

I also made castings for the brake lever and the sideframe extension that goes above it. Here's how the sideframes look with the brake cylinder, brake rod, lever and extension in place:

 

 

 

That's all for now, more later.

 

.

 

[Ray Dunakin]

 

 Hmm, one pic got messed up in the last post, and I don't see any way to edit the post so here's the pic...

I was concerned about the sand lines, which seem to be in a position where they are likely to get banged up a bit in use. So I inserted brass rods into the mold prior to casting:

 

 

 

[Ray Dunakin]

I've finished the trucks on the RS-3. First,  here's a "before" photo showing one of the stock trucks for comparison:

 

 

And now here is the finished truck:

 

 

 

And a couple detail close ups:

 

 

 

 

 

 

This truck has the cast brake shoe assemblies:

 

 

 

Prior to painting, I masked off the openings to the motor and gears. Then I used a q-tip to smear vaseline onto the tread and flange of the wheels. I applied a coat of gray primer, then a coat of Rustoleum gloss black.

 

To weather it, I began by mixing some Model Master "Gun Metal" and "Steel" paint together, and dry-brushed it onto the areas that seemed likely to become scraped or scratched. All the rest of the weathering was done using Apple Barrel flat craft acrylics. Next I added some rusty colors. Some of this rusty color was applied directly over the "metallic" colors, then rubbed partly off. When this had dried, I went over the whole thing with a wash of dusty gray-tan mix. When that dried, I added a mix of "apricot" yellow and black to a few areas, to represent grease. The final coat was a very thin wash of blue-black over the whole thing. 

 

Once the final wash was dry, rubbed my fingers over various parts of the trucks, removing some of the thin layers of acrylic and letting some of the black undercoat show through. Then I sprayed a light dusting of Krylon UV matte finish over the whole thing. 

 

The weathering is a bit understated, meant to look well-used but not overly grimy. It looks a little better in person than in the photos. I'm not sure if it's enough though, but I can always add more weathering to it later if necessary. .

 

 

.

[Ray Dunakin]

This is one of those projects where one thing leads to another...

 

Having made the deck wider, I decided that the fuel tank needed to be wider as well, so I built a completely new fuel tank. This actually works out well though because I now have room to fit the speaker in the tank, eliminating the risk of moisture damage posed by the factory speaker location. And of course I also got to detail it out nicely too.

 

Here's the original fuel tank:

 

 

And here's the new one:

 

 

 

 

The areas that have been patched with putty look pretty ugly now but it'll look much nicer when it's painted:

 

 

 

In this photo you can see where I'll be mounting the speaker. I still need to drill a bunch of little holes to form a speaker grill:

 

 

 

 

The original air tanks weren't worth reusing, so I'm replacing them too. The new tanks will be wider and more detailed. Here a shot of the new tank next to the old one:

 

 

 

A closer view of the new tank (I still need to build the second air tank for the other side):

 

 

 

Here's how the fuel and air tank will fit together. I still have to add the plumbing, too:

 

 

 

 

I already had some domes, but I didn't have any styrene tubes in the correct size for the air tanks. So rather than order them online and have to wait to have them delivered, I found a pair of plastic knitting needles at Michael's that were exactly the right size!

 

 

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[IRB Souther Engineer]

Those look a lot better then the stock parts!

[Ray Dunakin]

Time for another update...

 

I ran into a little snag with those new air tanks.  Although they're the same length as the originals, they're wider and are designed to mount more realistically. The originals are flat on one side and mount up under the edge of the frame:

 

 

 

 

 

Mine are intended to mount on the frame, like the real ones do. Trouble is, they foul the sand lines on the front truck:

 

 

 

 

So I had to order new, elliptical domes to replace the hemispheric domes. This reduces the total length of each tank by at least a quarter inch, more than enough to clear the sand lines. It also makes the tanks more accurate, as most of the RS-3's I've seen have tanks with elliptical ends:

 

 

 

 

While I was waiting for those new domes to arrive, I started work on the front pilot. I had hoped to be able to use most of the stock parts, but decided that too many changes were needed, so it was simpler to scratch-build. I did retain the rear portion of the pilot, since this has the tabs and such needed to mount it to the frame.

 

I began by cutting off the poling pockets. Then I glued on styrene extensions to widen the pilot. I also used a Dremel with a small carving bit to lengthen the slots that support the steps:

 

  

 

 

Then I decided to mount the steps differently, so I filled in the slots. This would have been easier to do if I had not already added some bolt details. I also sanded the poling pockets smaller and glued them back on, in their new positions:

 

  

 

 

I couldn't find anything better suited to represent the steel grill used on the steps, so I reused the original steps from the model. However, I sanded them to about half their original thickness:

 

  

 

 

I built up a completely new front section of the pilot. This was glued to the rear section, rather than being attached with screws as the original parts were. I changed the position of the steps, to fit the now-wider pilot:

 

  

 

Here's how it looks on the frame:

 

 

 

  

 

I had to take some liberties with it, particularly at the coupler pocket, but I think I captured the essence of the prototype pretty well. I still have to add some more details, such as the air hose, MU cables, grab irons, lift bar, etc.

 

 

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[Ray Dunakin]

Progress has been a little slow this week, but it's getting there. Here's the latest update...

 

I decided to mount the air tanks to the fuel/water tank assembly, rather than mounting them directly to the chassis. I used some small screws from an old camera:

 

 

 

 

 

Both the front and rear pilots are basically finished. The brake hoses are from Phil's Narrow Gauge -- I modified them slightly for this application. I still need to make some MU cables. The handrails and associated stuff will be added later:

 

 

 

I put the whole thing together temporarily just to see how it looks:

 

 

 

 

 

That's it for now. Currently I'm working on the cab interior... more updates to come.

 

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[Ray Dunakin]

I've finished the cab interior details. I didn't bother trying to include every single detail of the prototype. I just wanted to include enough of the major features, enough to give the impression that it's all there. As it is, much of what I did include will be difficult to see anyway. Here's a shot of the control stand under construction:

 

 

 

 

And here's the complete interior assembly. This assembly slides up into the cab from below. The floor was made to look like old wood with worn paint, as seen in some RS-3 pics I found:

 

 

 

 

 

On the fireman's side, I added a toolbox and grease bucket. These were cast from molds I made of originals I found on ebay. Everything else in the cab is scratch-built. The toolbox and bucket help support the end panels:

 

 

 

Oops! I made the seats a little bit too tall. Fortunately that's easy to fix. The seats are not glued down, they are secured with screws. I'll just remove them, cut the seats off the posts, shorten the posts, and glue the seats back together.

 

 

BTW, the seated figure is from SLM, and will be serving as the engineer until I get around to sculpting some custom figures for this loco.

 

 

.

 

 

[IRB Souther Engineer]

Very nice! I like the paint job.

[dwbeckett]

I have 4 ready to ship just give me quoat. the delta northern need's some matching road switcher's

very good work, wish i had my computer when i was in the hospital, eventhough i missed my birthday run, it would have been nice to follow your progess.

dave home finally

[Ray Dunakin]

Finally, another update! 

 

One of my biggest concerns when I started this project, was how to do the handrail supports. They need to be tough and rigid, slightly flexible but not brittle, and they need to be removable. I also wanted them to be as close to the prototype as possible. I considered using brass rod, but it's round, and the real thing is made of flat slabs. Brass bar stock might work but is not easy to find in such a small size. Brass would also be tough to work with, especially drilling the holes for the handrails to run through. And brass doesn't spring back if it gets bent over. 

 

Then I hit on a solution: Rectangular carbon fiber rod! These are sold by Midwest Products and can be found in many hobby shops, in a variety of sizes. It's a high strength composite material used in aircraft. It's very rigid yet somewhat flexible, and extremely hard to break. 

 

I used some carbon fiber rod that measures .019" thick by  .118" wide. As tough as it is, it can be split lengthwise, so I laminated some strips of .010" thick styrene to it. I was then able to drill holes through the supports without splitting the carbon fiber. I also added brackets and simulated bolts/nuts made of styrene. Here are some pics:

 

 

 

 

 

The handrail supports are designed to fit into slots in the deck and frame of the engine. This presented another problem: How to create deep, narrow slots? I have no tools capable of doing that. So my solution is to drill round holes, fill them with epoxy putty, then use a homemade tool to press the slots into the putty. Here's a photo of the tool I made, and a chunk of scrap styrene used as a test subject:

 

 

 

 

This worked just fine. The top surface of the putty came out a little rough on this test piece but I think I can do better. Most of it will be hidden by the bracket anyway. Here are a couple shots showing how the support fits into the slot on the test piece:

 

 

 

 

 

 

Now I just have to drill holes in the deck, add the putty, and form the slots for the model itself.

 

Meanwhile I also did a few other small things... I decided that the smokestack needed to be taller, to look right with the new larger cab, so I built up a new stack around the old one. I also created a bracket and air ringer for the bell, and made the metal "cabinets" on the deck behind the cab. I don't have pics of these changes yet.

 

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[Ray Dunakin]

Haven't had as much time as usual for modeling lately but I am making a little progress...

 

I finished the handrails along the sides of the engine. Here are a few shots with the handrails temporarily installed. (The fuel tank, air tanks and a few other items have been removed.):

 

 

 

 

 

In this photo you can see the "cabinets" that form the raised part of the deck, behind the cab:

 

 

 

 

I still have to make the handrails and other details for the ends of the pilots:

 

 

 

 

I used brass tubing to make "sockets" for the handrails to plug into where they connect to the pilot:

 

 

 

 

Here's a close up photo of the new, larger smokestack, and the bell with air ringer. The bell has already been painted but is not yet glued in place:

 

[img]http://www.raydunakin.com/Site/IRR_RS3_Conversion_files/Media/IMG_1893/IMG_1893.jpgv 

 

 

Well, that's all for now. It's getting close to the finish line!