bogieman

This would have been a better picture to use for the prototype as it shows the grilles not yet blanked-off and no fuel tender. A fuel tender is on my list to build though.

Thanks Zephyr! I do have a bit of a mashup of the as-built and modified versions. Originally, they were built with the air intakes all on the sides and none on the roof as I have but UP modified them to add the grilles on the top behind the cab and closed off many of the side grilles. I bought of bunch of 2x2 yellow tiles to modify the side grilles but haven't put them on yet, not sure I will as I don't find them very attractive. Dave

Thanks! I didn't mention it, but the bogie bolsters have a pitch degree of freedom relative to the underframe so they can negotiate vertical curvature in the rail profile, which they need to make it up and down the grades on my layout where the transitions are not as gentle as they are on real railroads. I designed locomotive and freight car bogies for 40 years so I do have some experience in the field. Dave

Thanks much! No, credit for the stickers goes to Andy at OKBrickworks, who does really great work. When you buy the plans for Sava's F7A&B from Brick Train Depot, you can specify either the SP Black Widow version or a Union Pacific yellow version. The assembly instructions are downloaded and OKBrickworks mails out the decals. Dave

As a bogie designer, I have always been intrigued with the 8-axle first and second generation Gas Turbine Electric locomotives (GTEL) built by GE in the 1950's for the Union Pacific RR. These used a single gas turbine rated at 4,500 HP and rode on a pair of span bolster 4-axle bogies comprised of a pair of 2-axle equalizer bogies with the draft gear and coupler carried integrally on the span bolster casting. I'm sure the designers did this to limit the length of coupler required to negotiate a reasonable minimum curve radius - this arrangement is similar to most all Lego trains where the bogie carries the coupler. These were long locomotives, 83.5 feet over couplers (25.5m). Besides the gas turbine, they had a small diesel engine for hosteling and to start the turbine engine. Unfortunately, all of the first and second generation locos were scrapped, the bogies saved and later used under GE U50 locomotives. The third and last generation had a larger 8,500 HP turbine and was two six axle locos coupled together - two of those were saved and are in RR museums. Here's a photo of the first generation loco I modeled: I I modeled it in 1:48 scale (8 wide); Andy at OKBrickworks created the decals for it: I 3D-printed the windshield frame as I did for my F7A model and painted it a reasonably close match to Lego Yellow. The model is powered with 4 PUP train motors that I modified by replacing the PUP cable with a pair of very flexible wires that pass into the carbody to connect to the controller, a SoundTrax Tsunami 2 4400 DCC which has a 4 amp capacity. It's powered by 4 - 18650 batteries in series giving nominally 14.8V to an Airwire Convrtr 60X that receives commands from an Airwire wireless throttle which it translates to DCC commands to drive the Tsunami 2. Sound effects from the Tsunami 2, which include all the turbine sounds, a played thru a 40mm in the "battery box" between the bogies. It also controls the lighting effects. This system is step up from the MRC LocoGenie I've used in my previous Lego locos for motor control, sound and lighting. With the long, wide carbody, there is plenty of room for the batteries and electronics. The roof lifts off in two parts to access the batteries and power switch. The Airwire receiver is visible in the picture, the Tsunami board is below the red tiles beneath it. The Airwire and Tsunami can both take up to 24V input, so I went ahead with 4 battery cells instead of the 3 I usually use. I've done a lot of pulling with this loco up the 4% grade on my layout with heavy trains and the train motors seem fine so far. Here is very long video showing the model in action before the decals were applied: The final tasks I have yet to do is to rearrange the cab interior to fit a pair of minifigures and create a fuel tender. Dave

Agree with ColletArrow, very nicely done. Love all the LED's you've added.

Looks really great. Since you are adding lighting, you need to find a way to make the ceiling fans rotate! Kidding of course, but would be awesome. Dave

Thanks all for the comments, appreciated! Dave

Nice work! I'm also having trouble seeing the differences so all look good to me. I wonder if you could use a plate with clip: https://www.bricklink.com/v2/catalog/catalogitem.page?P=4085b&name=Plate, Modified 1 x 1 with U Clip Thin (Vertical Grip)&category=[Plate, Modified]#T=S&C=88&O={"color":"88","iconly":0} to support the horizontal side rail at the free end, it just looks like it needs some support. Dave

Love the bonus Amtrak livery! Nicely done. Dave

A wonderful video Thorsten! I appreciate the time you spent to make the explanatory captions. It works flawlessly. The programming is way beyond what I can do or desire to do, I'm one to just do manual operation, but I love it. Dave

Thanks Dennis, I might need to take you up on that, the Dr. says I have to lay off the Naproxen Sodium to save my kidney function! But seriously, I think that is in the plan when BTD is ready, you need to prod Cam on Discord. Thanks! As far as design process, I started with one of the many webpages with Lego brick dimensions, then got my caliper out to take some measurements. I own a seat of ProEngineer (now Creo) from my consulting days so used that for the 3D design while looking at F unit pictures to estimate the window size and shape, then did test prints and iterated the shape and print support and orientation until I was happy with the fit. The clutch of the studs surprised me actually how good it was. I have a small metal cutting bandsaw that made cutting out the windshield glass easy.

Thanks all! Ivan, I haven't done a design for a 6-wide windshield frame since all my models are 8W. Looking at the construction of the LEGO F7 10020 set, it would take a redesign of much of the front to do something similar. Dave

Thanks, Brick Train Depot will be selling the windshields and frame, hopefully in the near future.

Thanks Zephyr. I did make a version using the 1x2x3 window glass but I felt the window opening was too small and didn't look right; it would work in a 6 wide version I'm sure though. I printed it in black ABS filament but sanded and painted it to make it smooth and glossy to try to match the Lego black. I tried acetone smoothing the ABS but it warped it badly. I think I printed 12 or more samples to get the shape right and figure out the best print orientation. I have been working with Brick Train Depot to sell this design, but not sure how soon they'll be ready to offer it. I designed the layout so I didn't have to crawl underneath it to access all parts of it, hence the shape. I've had both knees replaced so crawling without putting on knee pads it a no-go. Dave

Thanks for the kind words Thorsten, I hope Beanie makes a quick recovery. The grandkids are here today playing around the layout, they don't have much interest in the trains, despite my best efforts, maybe in time. Dave

I bought plans on Brick Train Depot for the Tony Sava-designed F7A and B locos but when I got to assembling the windshield, I just wasn't satisfied how it looked and it's robustness. Since Lego doesn't offer parts to do what I considered satisfactory and since I own a 3D printer, I designed a windshield frame and windows that to me is a major improvement. By not requiring the internal supporting structure, it frees up space in the cab interior for engineer and fireman mini-figures. Here's the completed A-B set with the Southern Pacific Black Widow paint scheme: This shows the cab roof removed. The roof holds the windshield via the four studs attached, there is no attachment on the bottom. This is the windshield piece. I cut windshield glass from 1x4x6 Glass 57895 that snap into the frame with nubs on each end. I opened up the interior to fit a battery holder with 3 - 18650 batteries: There are two train motors in the A unit and one in the B unit which is connected by a 4-conductor 3mm plug/jack to connect the B unit motor and it's rear headlight. As I have on several of my other locos, I am using a MRC Loco Genie wireless DCC system to provide the motor control, lighting, and sound functions. The 40mm speaker is mounted on the floor at the rear of the A unit. I purchased PUP jacks from China to connect the motors without having to cut off the plugs. These are the control components; there is an audio amplifier to the left of the speaker. I used 1206 SMD LED's for lighting: Here's a shaky and poorly narrated video of the locomotive in operation: Dave

Terrific work! Looking forward to the video, particularly with the turntable in action.

Thanks for your encouragement Benn and Thorsten, will do. The half-plate offset on the side doors looks great, I'd love to see the detail on how you achieved that. I assume that's a red sticker on the top of the door to match the sidewall color, a nice touch. Dave

You're truck sideframes look really good. I'm a big proponent of adding custom 3D printed parts to Lego models where I feel there is not a good brick-built solution. I've recently made my own windshield frames for an 8-wide EMD F7 and a GE 4500HP 1st gen gas turbine loco. But I'm reluctant to post them on this forum as I expect they will be controversial. Dave

Benn, Will you have your own layout display at Brickworld or are you participating with a group? I plan to attend and look forward to seeing this great train! Dave

Beautiful, one of my favorite trains!

Thanks for your positive comments. I'm not sure what I want to do with this design element, I've thought of marketing it but I don't feel it works well enough yet; on occasion, it stops for a few seconds and restarts and I haven't troubleshot it to understand why. So I am reluctant to share my design at this time. Thanks!

Very nicely done Ricky! Any thought to use a prototypical wheel size? AEM7's had 51" diameter wheels which would be #8 size at 1:48 scale from the wheel chart posted the below thread, page 2 I had some minor involvement at EMD with the design of the locos so always have been a fan of them. Their big wheels always gave them a special look. Dave

Love it, supported.