CNJ DRX-6-4-2000 project

Looking forward to seeing this develop.  Only saw one in real life once, resting and vfc rusting on  siding in jersey city.

Looking forward to the project also. Note, the Centipede Babyface is a different face profile. You may not care as you are willing to deal with the sidewall taper. Just wanted to let you know if it “doesn’t look right” against pics. I too wish someone would make these shells available, hopefully via 3D printing. First Person Scale Models is considering it for a summer project. If interested please contact him, the more interest the better chance it will happen.

A better modeler than I would have used something like a bandsaw or possibly a bladerunner to ensure straight cuts of the centipede shell. Not having access to a bandsaw, and Amazon jacking up the price of a bladerunner $30 made me decide to try and do the cuts with a Dremel using a right angle attachment. Using a square, I applied masking tape in hopefully straight, perpendicular lines to use as a guide for the Dremel cuts.

Went through 3 standard cut off wheels on the 1st cut. Switched to one of the larger, reinforced wheels after that, and it did the job on the remaining 2 cuts (there'll be another cut, but I need to figure out how long the center section needs to be before I make that one). Next up, some filing and/or grinding to ensure the cuts are straight and smooth, then they'll be joined together.

@Trainmstr posted:

Looking forward to the project also. Note, the Centipede Babyface is a different face profile. You may not care as you are willing to deal with the sidewall taper. Just wanted to let you know if it “doesn’t look right” against pics. I too wish someone would make these shells available, hopefully via 3D printing. First Person Scale Models is considering it for a summer project. If interested please contact him, the more interest the better chance it will happen.

Considering what I'm attempting, and the scanty documentation available on the prototypes, there will be no rivet counting. Other than folks online, I doubt anyone who'll ever see it will have ever seen the original (heck, other than photos I'VE never seen the original). The main difference that I can see is the DRX-6-4-2000 and DR-4-4-1500's noses don't start curving in until past the front of the cab side windows, where the centipede starts curving in right in front of the cab door. The rest of the nose profile might differ slightly, but considering there aren't any models in O scale of the others (and how many widely distributed models of things like RS-3s are incorrect), I'm not sweating it.

As it is, I'll be off a few scale inches on the space between the cab window and cab door, but I want to be sure to leave enough material so that the cab door still operates. If it were a plastic shell, I'd work it closer, but since a die-cast shell is more difficult to work with, I'm not sweating it. I'll be moving the running numbers back to the correct position, and filling in the holes where the centipede's number boards attached.

May take a crack at 3D printing the pilot, if that doesn't turn out well, I can always pick up a couple of the Lionel ones, even if I have to wait until November to get them half off. I've talked to Zach about purchasing his DR-4-4-1500 model, but it's currently in a very rudimentary state.

@necrails posted:

Looking forward to seeing this develop.  Only saw one in real life once, resting and vfc rusting on  siding in jersey city.

I suspect that's the same one that I'm modelling, 2004. Long after the other 5 were removed from service, it was still being used, though not fully operational. Think it stuck around until at least 1968.

This reminds me of my project from about 15 years ago...still sitting in a box. Combining the Weaver BF16s A-B shells to make a single BP20 passenger shark A-unit.  This was before Weaver produced the brass BP20. Of course, they were introduced right when I couldn't afford it (2nd kid). Anyway, I chickened out right at cutting the back off the A and the front of the B. So it waits...maybe I'll learn enough from watching your posts to get it out and restart.

Finished the cuts (at least on this shell), joined them together. Now  to remove unwanted details, and add in the correct details, an, of course, figure which direction to go with the other end.

Removing detail. While the sides are similar, the placement isn't, so much of the detail on both the sides and roof will be removed and then replaced. Thankfully a sanding wheel on the Dremel handles this fairly easily. Wish I had better pictures of the roof detail, but surprisingly almost no one seems to take pictures of the roofs of train engines!

Very interesting.  Nice work . Looking forward to seeing more of this engine.

Just a prototype for the roof louver detail, will actually be further back over the "center" section, but at the moment there's a big hole where it goes. Have to work on the rest of the roof detail. Basing it off of the Red Ball HO brass model, figure that'll be as correct as anything else out there. https://brasstrains.com/Classi...nted-1971-Run-Kumata

Also printed out a jig to see if I have the curve of the roof correct for roof panels I'll be printing. Looks great except for the corners, which will be adjusted.

Most of the roof detail has been modeled, will be tweaked as I see it on the locomotive. Shown are 3 of the 5 roof detail groups, group 4 and 5 are just 1 and 2 rotated 180 degrees. Each group will take around 4 hours to print, but I'll probably only do 1 per day.

And here it is printed. Broke while I was removing it from the supports, but it'll do for sizing. Also have to re-work the detail on the center box-like thing, as it isn't very apparent on the printed piece.

Okay, everything for the roof detail is done and scaled correctly. Just taped in place at the moment (2 panels will be repeated and reversed on the other end), the roof will need to be filled in and smoothed out for painting before it's applied. Glad it looks like Baldwin just riveted on 5 panels (of disparate size) on the roof! I have most of the detail removed from one side of the body (I'll re-add it correctly later). Donor shell for the other cab is on its way, will hopefully show up this weekend if the snow hasn't slowed delivery.

While researching, I discovered that the Red Ball brass has a fairly serious error. The small door in the side of the locomotive is located in the same spot (relatively, ie., on the "left" end no matter which side you view it from), and they have it towards the rear of the engine (the end without the air tanks) on both sides. Tricky, as I could only find one picture of the prototype's left side. This is why you can't blindly base your models on other people's models.

Once the entire shell is together and unwanted detail is removed, I'll move the running numbers back, drill for the marker lights, and re-shape the cab slightly.

Today's progress, it's now a double-ender! Even more incorrectly located detail to be removed (sigh!). I'm printing the headlight lenses, side grill numbers, and hopefully a cab side window that didn't come with one of the donor shells (if that works, I'll take a crack at the windshield). I've compiled a list of detail parts I need to design/print, including the undercarriage detail, there's still a ton of work to be done, but it's moving along!

Most body detail removed. Started designing undercarriage detail, first test print done (parts of the latch handles are missing, forgot they needed supports). Currently working on the "front" grouping with the air tanks. Probably dis-assemble the PA-1 "donor" this weekend, and figure where best to cut it to add the needed 3". Then once it's stretched, I'll finalize the undercarriage stuff and print that. Meanwhile, filling and smoothing the body progresses...

Tomorrow I see if I can reshape the nose to eliminate the centipede's taper (waiting for filler to cure). Meanwhile, back at the ranch, I've been playing around with builder's plates. This pic shows one about an inch wide, which is still way too big. Have ones less than half that size, but working on improving legibility (number and build date are incorrect on this first prototype, current ones are correct)...

Still working on shaping the cabs. Took a 1st shot at making a pilot, have the curvature down, have to tweak the size and placements of the arcs on the end and bottom. Hole for the coupler will be added after I get those right.

Pilot is ready to prototype (I've got another item in the printer currently, so it'll have to wait, rendered image provided until then). Apparently the thicker die-cast shell doesn't fit on a chassis made for a plastic shell, so that's going to need modified, hopefully I can thin down each side rather than have to cut things.

2" speaker from the "donor" engine won't fit in any of the undercarriage pieces, so I'll either need to find a smaller 8 ohm one, or relocate it.

Going to cut the chassis, and attempt to slim down the sides while I'm waiting for the printer...

I sent you an email with pics that I hope will help you. I’m assuming you’re going to replicate the second batch with the simplified (3) side vents. Don’t forget there’s a short door on each side, looks to be off centerline.

@Trainmstr posted:

I sent you an email with pics that I hope will help you. I’m assuming you’re going to replicate the second batch with the simplified (3) side vents. Don’t forget there’s a short door on each side, looks to be off centerline.

Yes, I'm making the later version one. Thanks for the pictures, they'll be a great help!

Okay, pilot printed, and it works perfectly. Except for not being able to fit the coupler through the hole where the coupler is supposed to go through. The back of the coupler will go through it, but in order to assemble it without completely removing the truck from the chassis (and I haven't yet figured out how to do that), either the knuckle of the coupler needs to be able to pass through the hole in the pilot, or there needs to be a hole in the pilot so the coupler can be attached, which might be seen as the pilot and truck swivel to negotiate curves.

So I'm faced with either opening the hole for the coupler up to unrealistic proportions to allow the standard Lionel non-scale coupler to fit, or to add a hole on top of the pilot so the coupler can be attached. Will experiment further tomorrow.

Have the chassis separated, and am currently working on fitting both ends into the shell. Have run into a clearance issue with the electronics, which should be able to be resolved by relocating them closer to the center of the engine.

Some good progress today! Got both sets of wheels fitting in the shell in the correct position, and a prototype pilot attached. Electrocoupler fits, manual one doesn't. Even though this has TMCC, I don't think it supports electrocouplers. Since I don't plan on using it for a switcher, I can live with it. Now I need to join the 2 ends of the chassis together, and press on with the bodywork...

Wow, this is coming together very nicely with a lot of skill craft work.   Three of us thought about and actually detail planned to build a model of the similar GM&O passenger Baldwins.   The GM&O's locos were standard single cab baby faces on the same chassis as the CNJ locos.   We even have the MTH Centipede shells to use for making the modifications.   Our GM&O locos would not be as difficult as the CNJ double enders but still a challenge.  We had decided that we would be able to look past the nose side tapers on our models.  We may still get back to this project, with your project as our encouragement.   Nice work.     Brian J. 

@Brian J posted:

Wow, this is coming together very nicely with a lot of skill craft work.   Three of us thought about and actually detail planned to build a model of the similar GM&O passenger Baldwins.   The GM&O's locos were standard single cab baby faces on the same chassis as the CNJ locos.   We even have the MTH Centipede shells to use for making the modifications.   Our GM&O locos would not be as difficult as the CNJ double enders but still a challenge.  We had decided that we would be able to look past the nose side tapers on our models.  We may still get back to this project, with your project as our encouragement.   Nice work.     Brian J.

If you do decide to do it, keep watch for a deal on a DL-109 in case one comes up, as that'll save on extending the length of the chassis. You'll still possibly need to modify the shape of the chassis nose to fit the centipede shell's taper, but it'll be a lot less work than using a PA-1's chassis.

Another snow day, so more time to work on the train! I was working on adding detail to the pilot. Have the 2 brake lines, attempted to print a chain around the ends, but small scale chain is next to impossible to 3D print. There are valve handles, but they won't print unless I change the orientation of the part, which triples the print time. As I'm still prototyping, I'm not worrying about them for now. Also made the hose on the lower line longer after this print.

Joining the two chassis pieces together. Wanted something that would maintain the structural strength. Thickest sheet metal I could get easily was 1/16th of an inch, and 1/4" steel bars stopped at 2" wide. Decided to cut a corner bracket in 2, and grind down the ends of each piece on the bench grinder so it would fit better in the hole, while still having a good bit of overlap to provide strength. There's a lot going on in this picture. The shell is being used as a straight edge to keep both ends properly aligned. The track is doing this too. The can of frosting and of chicken are counter-weighting the ends so they don't droop in the middle while they're being joined. I've removed all of the electronics except the motors and a switch (taking pictures as I went along to aid in re-assembly). Once the JB Weld is cured, I'll fill in gaps and holes as needed and clean things up. Then chassis fit will be checked, and mounting holes will be marked and drilled.

I've located a speaker that will fit in the undercarriage detail, and have added grill cutouts as well as mounts for it to the detail. Once the chassis cures, I'll check placement of the undercarriage detail to ensure that the trucks can rotate properly, and shorten it if needed before printing out final versions.

UPDATE!

And here she is, for the first time, sitting on her newly fabbed chassis! Undercarriage detail is still just placed beneath it prior to clearance testing and final fabrication.

Looks great so far.  Nice fun project during a pandemic.  Enjoy seeing the photos of the progress you've made. 

Been working on it all day, but not a lot of progress to show yet. Decided to print the undercarriage and pilot detail separately to get the best results, then assemble them. Airtanks, pipes and filters have the glue drying, as does the fuel tank and it's sides. Speaker will be mounted in the fuel tank (grill is molded in the bottom). Pilots are printed, just waiting on the hoses to print. Once all the adhesives have cured, I'll hit them with a coat of primer. Paint was supposed to be here yesterday, but the good ol' USPS is up to their unreliable selves (had 2 different packages they're late delivering). Going with Tru-Color's C&O and B&O blue (TCP-072) and CNJ Tangerine (TCP-295).

Below is the detail for the brake hoses on the pilot, chain was supposed to go around the hoses and be hooked through the lower pilot opening, but it seems it's impossible to get the chain to print correctly. I may just go with some actual chain. Never mind the colors, they're just to help differentiate parts during construction, it all prints the same.

Undercarriage detail primed, drilled for mounting, and with speaker mounted. Found one from Mouser that both fit the fuel tank and the specs of the original one. As the "donor" engine was equipped with signalsounds, it had an 8 ohm 0.2 watt speaker. Unfortunately, the original's 50mm diameter wasn't going to cut it unless it was mounted in the body. May have to upgrade if I ever upgrade to a railsounds system, but this should work for now. Speaker

Work on the chassis is almost done. Frame sides are now painted black, "stretched" portion has been filled and is just about ready to prime and paint. Still need to mark and drill holes for mounting the shell and the undercarriage detail. I could use a few more snow days, and the couplers and mounting parts that I ordered from Lionel to show up...

Parts came from Lionel, and fortunately I was able to find a spring that apparently they couldn't, so now the coupler and pilots can be attached at both ends. Not that I'm ready for that, won't happen until they're painted, and hopefully everything will be painted in 2 shots, tangerine first, then blue. Not a fan of cleaning the airbrush...

Roof is filled, sanded and awaiting detail to be attached, which unfortunately won't happen until after I get the sides finished. Most of the bodywork on the cabs is finished, still some final shaping and hand sanding to do, but they're close to what they should be (except for needing to re-add holes for marker lights, running numbers, and sand filler hatches).

Got the side doors cut today after work. Can't say it was fun, and I managed to break the tips off 2 files (because I'm an idiot who should know not to use them to pry things), but they're there.

Started prototyping the side doors. All models I've seen have flush doors with windows, however the actual ones were recessed, and I've yet to see a picture of an actual engine with a discernable window in the side doors, so no windows on mine. Cab doors will open, but I don't think it's worth the effort for the side ones. Once I get the spacing and alignment down, detail such as the attachments for the grab irons and door handles will be added.

This is turning out great! Can’t wait to see the cab painted. Do you think using a metal shell rather than a plastic one made the kitbash easier?

Really looking forward to seeing this as a completed model.  What is the overall length of the locomotive?  What do you anticipate will be the minimum radius for it?  I never saw anything on the CNJ growing up that was blue and tangerine but have seen pictures, they all looked a bit weathered.

@Trainmstr posted:

This is turning out great! Can’t wait to see the cab painted. Do you think using a metal shell rather than a plastic one made the kitbash easier?

Interesting question. I basically went with what was available. I know Lionel and MTH both make Centipedes, but only Lionel shells were available when I started this (and I'm not sure if MTH's are plastic or die-cast). So it wasn't like I had a choice. Given the choice, I'd probably have chosen plastic, as it's a heck of a lot easier to cut, drill, etc. The metal is probably more forgiving to work with, but it definitely takes more work. If it had been plastic, I'd probably have moved the cab door slightly closer to the cab window, but being metal I didn't want to cut it too close and possibly have a weak joint if there weren't enough metal on both sides. 

@necrails posted:

Really looking forward to seeing this as a completed model.  What is the overall length of the locomotive?  What do you anticipate will be the minimum radius for it?  I never saw anything on the CNJ growing up that was blue and tangerine but have seen pictures, they all looked a bit weathered.

It's 20", which is based on the 80' length of a Baldwin DR-6-4-2000 from pulling face to pulling face. Wasn't able find specs or plans of the CNJ's DRX-6-4-2000 variant, so I'm just going to assume they're the same length and run with it. As for minimum radius, The PA1 would do 31" curves before I extended it 3". I'm assuming this will require 42", but haven't tested it yet. As with many O 3-rail models, the pilots attach to the trucks, which while not prototypical, allows a tighter turning radius.

Great on the minimun radius although at 20 inches long it will have some overhang.  I have a vague memory of there being drawings of this locomotive in model railroader back in the late 60s early 70s.  The only reason I have any memory of it is because this was so unique.  If i turn up something I'll forward it to you.

Necrails, if you turn up any plans, please share. At least magazine, year, and issue. Thanks.

Have the doors finished and printed:

Hard to see in the photo, but the blocks near the top sides of the frame have 2 nuts on the top and a hole for the grab iron on the bottom. Now to finish smoothing out the sides and mount them...

Finished the detail for the pilots as well, including hoses and the stirrup steps. They're just about ready to be ready to be primed and painted.

Also finished the cab roof vent pipes. Probably drill and mount those tomorrow, as well as possibly the center roof detail with the exhaust stacks.

Last of the "ugly" photos (hopefully). Finished with the machine sanding, now for a bit of hand sanding, and a quick coat of primer so I can see if there are any problem areas which need more work. Cab vent pipes are in. Roof detail and side door just sitting in place, will be installed once sanding is done.

Holes drilled for classification lights and sand fill hatches. Still have to  add holes for the number boards. Final body touch-ups will be done, then side and roof detail added...

Attached the sand filler hatches, pic of that once they're cleaned up a bit.

Was trying to figure out a good way to attach the numberboards without having to cut huge holes in the shell like Lionel did for the original ones, since these are located further back and I can't re-use the original holes (which have been filled). Since I want them to light, I'm going to print them with transparent resin. What I decided to to is to attach a 3 mm post (which should act as a light pipe for the LED) to the back of them (which is the same size as the LEDs which I"m using for these and the classification lights). That way I can drill the same size hole I did for the classification lights, mount the number boards flush, and on the inside will be a printed sleeve with a 3 mm hole which will slip over the post on the back of the number boards AND provide a seat for the LED. Concept illustration below.  Once I run off a prototype, I'll adjust the length of the post and sleeve as needed before final prints.

Feels like I get a lot less work done when I have to go to work. If I stopped going to work, I'd probably be finished already!

Grills have been re-painted and masked off. Sand filler hatches are in. Side doors are in. Still some minor body work to be done before I start adding the side and roof detail. Next up, marking and drilling the holes for the number boards and the lower grab irons on the front(s) and pilots. They'll be attached later so I don't screw them up while I'm still working.

Decided to go a different way with the cab side windows. I don't have them all, and printing one with "clear" resin was producing less than satisfactory results. Changed the frame design, they'll now have clear acetate glued to the rear of them for window panes, the fit is great. I'll probably replace all 4 so that they match. Just wish I knew if they were silver or orange, don't have any good color prototype photos which show them. Same deal with the grills. The B&W photos clearly show they're NOT 2-tone, but are they black or blue?

Anyway, here's where we stand at the moment:

Not a lot of visible progress (been rebuilding a gazebo all weekend), but the majority of the body work is done. A few small areas need touched up, but pretty much everything is straight and smooth now. Printing the (hopefully) final pieces for the number boards.