What fun; I started this project a few years ago, mothballed it and am now trying to get it finished. At this point, I'm just trying to get the damned thing to run half-decently (OK, I can hear you guys in the back snickering already).
Oh, it's the 3-truck version in HO. So I've got it running, sorta. At this point, I'm only running the basic mechanism without the "shay" shaft; I'm sure a whole 'nother bunch of headaches awaits me there. There are two serious problems (well, not counting the glaring fact that it's so damn NOISY). The first is pulsation; the second is a more grinding, hammering sound.
I've been over pretty much everything so far: motor runs fine (Sagami can). I've run in all the enclosed gearboxes with toothpaste. Don't want to revive this point of contention, but I can say that it definitely made a positive improvement that was worthwhile. I ran all three trucks and the bull-gear box full of toothpaste separately. The three trucks are well-greased (I used general purpose white lithium grease), while the bull gear is oiled. I'm thinking of opening the bull gear box and trying grease there.
The pulsation seems to be the same frequency as wheel rotation.
So apart from the pulsation (and the NOISE), the 2-truck lock runs pretty well. But as soon as I add the "tender", I get this really horrible new noise that sounds as if one or more wheels is off the rails and dragging on the ties. Doesn't get better going faster or slower. Observing things up close, I suspect it is coming from the rear loco truck, or from the rear universal connection, as I can see the shaft bouncing up and down. I had to weight the "tender" to keep the loco from spinning it every time it starts up; this seems like yet another major design flaw on MDC's part (but easily solved with a lead weight).
So, anyone been down this track who can help out? Reading through the archives here, I found one suggestion that might work: just not powering the 3rd truck at all (leave out the worm gear and cut the trailing loco truck shaft short). While this would work, I'm afraid it might not allow me to run electrical pickup to the tender wheels (too much drag).
About electrical pickup: it's well known that this is a major, major flaw with this loco. But aha! I have solved this part of the equation. Here's what I did: when I first tried putting it together, I used the pickup wipers supplied with the kit, which were fairly thick copper. Way too thick, as it turns out; if they were set up for decent contact, they acted as brake shoes on the wheel rims. So when I wrote MDC about some other spare parts I needed, I asked for some replacement wipers. They very graciously sent me a whole bunch--of their new style ones, which are *much* thinner than the original ones. In fact, they're perfect.
Of course, the first thing I did was ditch their stupid "polish the underframe and let the wiper rub on it" method of connection, which is just about guaranteed not to work. I soldered wires to all 4 wipers on the loco, and if they're carefully bent to contact the backs of the wheels, I get excellent electrical performance. (I even added connectors so I can disassemble the model without having dangling wires breaking off.)
So I'd really like to try to get that 3rd truck working, if anyone has any ideas.
By the way: it appears since I started this project that the company (MDC) has been sold; anyone know how to get in touch with them? I tried one address I found from hunting around (mdcroundhouse.com) which is apparently off the air or never existed. Does one now go through Athearn? Horizon?