Barduck Posted March 28, 2021 Posted March 28, 2021 (edited) Only one 2-8-8-8-4T was ever built, a Mallet-type for the Virginian Railway in 1916. This is the one in the above photo, it is also the one that you are about to build using these instructions. Built by Baldwin Locomotive Works, it became the only example of their class Xa, so named due to the experimental nature of the locomotive. Like the same railroad’s large articulated electrics and the Erie Railroad 2-8-8-8-2s, it was nicknamed “Triplex”. The purpose of the Xa was to push heavy trains over steep inclines, requiring high tractive effort, but low speed, over short distances. The Xa worked on a difficult 14-mile section from Elmore to Clark’s Gap. The Xa’s center set of cylinders received high-pressure steam, and the exhaust from these was fed to the two other sets of cylinders, which were valved for low pressure.The right cylinder exhausted into the front set of low pressure cylinders, and the left into the rear set; this is also why the high pressure cylinders have the same diameter as the low pressure ones, whereas most mallet locomotives have much smaller high pressure cylinders. The front set exhausted through the smokebox and the rear set exhausted first through a feedwater heater in the tender and then to the open air through a large pipe, which can be seen in the photo. Since only half of the exhaust steam exited through the smokebox, firebox draft (and thus boiler heating) was poor. Although the boiler was large (in line with contemporary two-cylinder and four-cylinder practice), six large cylinders demanded more steam than even such a boiler could supply. With all six cylinders operating at their full pressure (which could not be sustained for very long), the Xa produced huge amounts of tractive effort that may have been the highest of any steam locomotive before or since (160,000 pounds-force in compound mode, which was the largest tractive effort for any locomotive up to the time,1914-1916).The Xa is also considered the largest tank engine ever built since the tender had driving wheels as well and thus contributed to traction. The problem of variable adhesion on the Xa’s tender unit was not a serious one, since pusher locomotives had frequent opportunities to take on additional fuel and water. The Xa was unable to sustain a speed greater than five miles an hour, since the six cylinders could easily consume more steam than the boiler could produce. The tender had a four-wheel truck at the rear to help guide the locomotive into curves when drifting back downhill after pushing a train over the hill. This MOC has around 2800 parts in her (and about 80 3D printed parts). She runs on PU, 1 battery, 2 Large motors. Decals made by OKBrickWorks.com Even as large as she is, she still manages to take R40 turns https://flic.kr/p/2kJu33v and switches: https://flic.kr/p/2kJq1K4 She can even take light graded slopes (1 plate/straight increase) https://flic.kr/p/2kMA1um Instructions available on Rebrickable Edited March 28, 2021 by Barduck typo Quote
Pdaitabird Posted March 28, 2021 Posted March 28, 2021 Wow, this is seriously impressive...even more that it can take standard curves! Quote
Feuer Zug Posted March 29, 2021 Posted March 29, 2021 That locomotive borders on insanity. Building it is a considerable accomplishment. Well done. Quote
ColletArrow Posted March 29, 2021 Posted March 29, 2021 Is that a locomotive in the video, or a very large caterpillar? This model is stupendous in just about every way - size, accuracy, detail and ability to negotiate standard TLG track. The chrome parts and custom decals top it all of nicely. I think the only possible improvement could be working lighting - fantastic work. How long did she take to design and build? Quote
Barduck Posted March 29, 2021 Author Posted March 29, 2021 (edited) 3 hours ago, ColletArrow said: How long did she take to design and build? Well, it is already V4. V1 got scrapped, V2 got burned to a crisp. V3, of which I have only done renders took about 2-2,5 months to redesign starting from V2. I pushed her a bit to enter the Brick Train Awards. But instead of building her, I finetuned her, extra hatches on the cabin roof, shortened her and the tender a bit, lowered the cabin roof, etc etc. And thus V4 was born. I recon, if I'd had to start from scratch she would have taken the better part of 6 months to design. Once the parts were ordered and printed (the valvegear is homemade, from design to printing) she took about 3 days to build at around 4 hours a day. That might seem long but I didn't want to push her and make building mistakes. And test while building (and even change the design a bit at some places to add more rigidity or change how something was connected. At the end testfase, where I was testing to see if she'd take R40 I made another change to enable her to do just that. All it took was changing the set up of the wheels on the second truck from F-B-F-B to B-F-B-F. To enable her to take R40 switches all I had to do was change the beam connecting the second (last loco truck) and the third (tender) truck from 9 long to 11 long with pins at hole 1 and 10. Even though she can take R40 (and actually I designed her with that in mind), she'll look a hell of a lot better on R104 curves and switches Edited March 29, 2021 by Barduck typo Quote
Toastie Posted March 29, 2021 Posted March 29, 2021 3 hours ago, Barduck said: Well, it is already V4 This is a wonderful design story! A strong demonstration of dedication. Of ingenuity. Of superb building skills. Of patience. Of so many more things that come to mind. As others have said: Beyond belief. Beyond anything, I can imagine. And yet: Reality. Wow. I am speechless. Congratulations, @Barduck This is fantastic. Thank you very much for sharing!!! Best wishes and have endless hours of fun! Thorsten Quote
Murtin Posted March 29, 2021 Posted March 29, 2021 Hats off to you, Barduck, Seeing this, I think I need a moment just to lift my jaw off the floor! Love all the incredible details, especially all that piping, plumbing and undercarriage. This is a work of art, thank you! Quote
brick-builds Posted March 30, 2021 Posted March 30, 2021 Wow, very good work. Do you have a video of the train? Quote
High_Admiral Posted March 30, 2021 Posted March 30, 2021 You've outdone yourself once again, great work on the Triplex! Quote
Barduck Posted March 30, 2021 Author Posted March 30, 2021 8 hours ago, brick-builds said: Wow, very good work. Do you have a video of the train? there's 3 linked in the topic 16 minutes ago, High_Admiral said: You've outdone yourself once again, great work on the Triplex! thanks, she's a complicated but fun build Quote
LEGOTrainBuilderSG Posted March 31, 2021 Posted March 31, 2021 Behemoth locomotive packed with intricate details. Love the coupling rod details. I am just so fascinated with the fact that it takes curves and switches so easily. Quote
CMF-1138 Posted March 31, 2021 Posted March 31, 2021 As others have said, this is simply amazing. The rods and valve gear assemblies are fascinating to watch. So much detail. Really well done! Quote
zephyr1934 Posted March 31, 2021 Posted March 31, 2021 That monster is insane! Amazing work, and unbelievable that it can do R40, so equally amazing engineering. Now you just need 100 coal cars to shove up the grade (grin) Quote
Dr Snotson Posted March 31, 2021 Posted March 31, 2021 This is why we do what we do... that`s it - that`s all! Awesome and inspiring piece of art! Quote
Barduck Posted April 5, 2021 Author Posted April 5, 2021 (edited) On 3/31/2021 at 4:31 PM, zephyr1934 said: That monster is insane! Amazing work, and unbelievable that it can do R40, so equally amazing engineering. Now you just need 100 coal cars to shove up the grade (grin) I'm afraid 100 coal cars are a bit above budget. Could you spot the differences with V3 (and V2)? On 3/31/2021 at 9:35 PM, Dr Snotson said: This is why we do what we do... that`s it - that`s all! Awesome and inspiring piece of art! not inspiring enough for myself, don't think I'll be tangling another steamer this year, this one was already enough Everybody else that commented (can't be quoting them all): thank you for your kind words on how much you like her, now of you go to Rebrickable and buy those plans Edited April 5, 2021 by Barduck Quote
TracerWingsong Posted January 9 Posted January 9 (edited) Hey!!! I love the and this triplex, (your design is incredible!) would be awesome to add in with my emerald night. I went onto the website and couldn’t find the plans. They still available? Edited January 9 by TracerWingsong Quote
JopieK Posted January 15 Posted January 15 Thanks for being part of Eurobricks and Train tech @TracerWingsong Enjoy your stay but please remember to read the rules, adhere to them and ask if something is not clear. Maybe @Barduck will be friendly enough to share some insights though. Quote
Barduck Posted January 16 Author Posted January 16 (edited) 14 hours ago, JopieK said: Thanks for being part of Eurobricks and Train tech @TracerWingsong Enjoy your stay but please remember to read the rules, adhere to them and ask if something is not clear. Maybe @Barduck will be friendly enough to share some insights though. I did pm as I didn't want to unnecessary boost this post. When I put the Triplex on Rebrickable I set a goal of how many sales I wanted it to be at and retired her when that goal was reached as I really wanted her to be a bit more exclusive. I may put her back as there still seems demand for it, but the 3D printed parts are a pain to make available as shipping is just way to costly with all the extra import taxes so I'll most probably be putting those as STL's up instead when I do return her Edited January 16 by Barduck typo Quote
JopieK Posted January 16 Posted January 16 @Barduck great! It a fantastic train, so no wonder others also fall for it! Quote
Gioppa Posted January 16 Posted January 16 11 hours ago, Barduck said: the 3D printed parts are a pain to make available as shipping is just way to costly with all the extra import taxes so I'll most probably be putting those as STL's up instead when I do return her If you made the STL is wonderful, i'm still think how to made that small plastic part...there is one piece is impossible to made with Lego Quote
Lyichir Posted January 16 Posted January 16 Really neat build! I'm from Virginia but despite my dad being a big train fan I'd never heard of this historical oddity—you've done a great job recreating it, especially given the challenge of working with Lego track and its sharp turns! Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.