This is a placeholder for ATSF Class 5000 "Madame Queen", this build is an experiment and goes against advice from other experienced modelers, mainly I want to see if I can make a good copy using parts that don't cost a lot. I do have another mechanism that is far better but I don't want to ruin that getting the dimensions etc right. So the base of this is two Bachmann J 4-8-4 class locomotives - these are the early ones that I got in NZ really cheaply. Madame Queen had 69 inch drivers, the Bachmann is 66 inches so it's close. The wheelbase of the prototype is 24 1/2 feet, this model comes out at 26 feet because I have a shim of styrene at the join so the CA glue bonds better. I will correct this a bit later. SO this whole thing is a Proof of Concept and a big experiment, hopefully it will be worthwhile. Please note no good running, intact J Class 4-8-4's were harmed only partly disassembled basket cases were harmed. Mechanism picture - note only two drivers fitted for wheelbase measurement.
Added all the drivers to see how it looked. All drivers rotate freely, it took me 2 hours work on the 3rd set of drivers to get them to turn freely!
Cut the new boiler from brass tube, very close to the prototypical 104 inches in diameter, I've cut the boiler slightly longer than the protoype to give me wriggle room with the cab. The cab will be a Bachmann 4-8-4 Northern type but it is not as long as the 4-8-4 so some cutting up will be in order. Yes it will have to sit lower down
Nice! Will you have to cut the flange off the middle driver, like the prototypes did, or is it not necessary on the model?
Hi Andy, I was hoping to leave it intact, I've seen a few HO Brass versions and they all have flanged drivers. This model is just the proof of concept - I have a better mechanism but didn't want to cut that up until I got a few things worked out.
So are you working yourself up to building a 2-8-8-8-2 triplex? Or maybe a Union Pacific 9000 class 4-12-2?
2-10-10-2; weren't those the ones the Santa Fe eventually cut apart and rebuilt as 2-10-2's? It's amazing how much time, money and effort went into building steam locomotives that were, for all intents and purposes, dismal failures, or at best never lived up to expectations.
Yes they did split them backup into 2-10-2's, they were on a mission to build ever more powerful steam locomotives, some worked out well some didn't
I have ordered a small motor from China as only a Bachmann motor will fit the space. This should run a lot better with the new motor. The contact strip isn't the best but I may be able to make a new one from phosphor bronze. The challenge is to get it running reliably and it'll need more weight. This one is a test bed for one based on a Spectrum J 4-8-4. I don't want to get that one wrong!!
They started as 2-10-2 types. They were rebuilt twice. The Santa Fe came up with an efficiency device called a reheater that they figured would allow a boiler half big enough to power a Mallet. They bet big on that technology. It wasn't a good bet.
There was a lot of "Dart Board Engineering" back in those days. Much like the development of high-power solid fuel rocket motors was back in the '50s and early '60s. There is a fine line between a motor and a bomb and back then they didn't know where that line was or even how to find it except by trial and error.
The small motor has arrived so I need to get moving on it. I'll probably need to get some thin phosphor bronze sheet, the Bachmann contact strip is a basket case on both J4-8-4's (no they aren't spectrums), I need to get a new worm gear so I can test the motor in situ.
I swapped out the new motor and used one from a Spectrum J4-8-4. Same motor but the Bachmann one smells a bit.
Beautiful work! Pardon my ignorance, but why do some wheels have much less (or no) counterweight than others? I can see having half as much counter-weight on the front and rear drivers due to having only one link of drive rod each (rather than two), but those don't even appear to have that much.
I've just cobbled the whole thing together. The wheels are off a J 4-8-4 but I have not put them in the correct order etc. I may have to correct some of the counterweights. I'm concentrating on getting a smooth running mechanism then I'll put everything where they should be, I'll also have to quarter them.