Hello All,
      Not sure if this should be here or in the HO section since there are so many "general" questions. If this should be in the HO section, I appologize to the admin and respectfully ask that this be moved to the proper location.

     First let me start by explaining a little about me and my work.
     I know next to nothing about these electric trains. So, please keep this fact in mind as I attempt to explain our set-up and problems. Also please forgive me if I do not know the proper term for some specific piece, part, tool or term. That is one of the reason I have joined these forums. I want to learn.
     I am a computer/maintenance Technician at a place called WonderWorks in Pigeon Forge, TN. (http://www.wonderworkstn.com ) We have a train set-up that is a display in our “Far-Out Art Gallery”.
     Here is a brief description of the action of the track and links to some pics I took.
    The oblong track simply runs around the outside edge of the table then enters a tunnel where it makes a large loop inside/underneath the hollowed out “mountain” and table cavity. Then it exits the tunnel on the opposite side to do it all over again.
     The effect, or “illusion” if you will, is that it is very obvious that the train is much longer than the tunnel, and the way the table looks, it appears to be a solid piece of wood. The overall effect leads you to believe the train “disappears” for a few seconds after it enters the tunnel. And yes, you would be amazed at the number of people that this simple “illusion” absolutely dumbfounds. I have heard all kinds of explanations given by people. From, “there are mirrors under the table”, to “It is on a timer, and when it enters the tunnel the power shuts off for a few seconds then kicks back on”. That one has got to be the stupidest one I hear, because as I said, it is VERY obvious that the train is MUCH longer than the tunnel is. Anyways……

   Full front view: http://i206.photobucket.com/albums/bb91/cloudkat1970/DSC02887.jpg
   Right side:
http://i206.photobucket.com/albums/bb91/cloudkat1970/DSC02889.jpg
   Left side:
http://i206.photobucket.com/albums/bb91/cloudkat1970/DSC02890.jpg
   â€œMountain”
http://i206.photobucket.com/albums/bb91/cloudkat1970/DSC02891.jpg
   Inside Loop (under Mtn.)
http://i206.photobucket.com/albums/bb91/cloudkat1970/DSC02892.jpg

     While there are 4 techs that work here (5, including the Technical Director), there are only 3 of us ( the TD and myself) that actually try to do any real work on, or even attempt to understand the workings of our train set-up.
     Here are some of the specifics of our train set-up:
   The track is approximately 35 feet (10.6 meters) long.
   We are currently running 1 (one) EMD GP50 (Norfolk & Western) engine (item # 61242), followed by 11 cars. Of which, all but one, I believe, are Bachmann cars.
It should also be noted here that the “coal carrier” behind the engine is attached to the engine by a one inch piece of thin monofilament fishing line and is also about 2/3 full of BB’s to add weight.
     We started having problems out of the original track, so it has since been replaced. Well, the outside track was replaced. The inner loop has not been replaced yet. That is the next thing to get done. Anyways, the outside track is now that “flex-track” stuff in the curves and all sections have been soldered together. (Soldering the sections together seems to have helped some). There is also some of that neoprene-like track underlayment under the track to help reduce the bouncing and vibrating. 
   There are 2 (two) Terminal Connectors (one each side of the track, one in front, one at the entrance to the tunnel) for power. We also have one section in the front that is one of those rerailer sections.
   Power is supplied by an MRC Power Command (Model 9500). Speaking of this unit, let me tell you what it is doing and my settings.
The track voltage fluxuates between 12 and 14, depending upon where the train is on the track.
The track current is approximately 0.1 - 0.2 when the train is on the outer track and 0.3 - 0.4 when the train is on the inner loop (the original track).
The throttle control is set to about 78 with the momentum switch set to Off.

     We do clean the track. We try to clean the track once a day, or at the least every other day or so. We are using cotton swabs (big Q-Tips) and a liquid track cleaner by Life-Like.

     The table, scenery and original track was custom built for us by an outside source.

     I guess the single most important thing that you guys need to know is that this train runs CONSTANTLY for about 15 hours every day. We are open 7 days a week, 365 days a year. Yes, including Christmas day, New Years and Thanksgiving. So this train sees A LOT more use than 99.9% of all other HO train sets on this planet.

     Now on to our problems;
   We constantly have to put this thing back on the track. I mean as much as 15 â€" 20 times a day. It mostly derails in the curve right before the tunnel and at the bottom of the inner loop. I have checked many times over for any nails sticking up or debris on the track in these locations. Sometimes this thing will run for hours straight without a problem. Then, BANG, you walk by and the engine is lying on its side next to the track. Or you walk by, notice the train is not coming out of the tunnel and upon looking under the “mountain”, you find the engine half off the track and just about every car behind it is off the track as well.
   Another thing this train will do every so often is get stuck trying to come out of the tunnel even though the downward and upward ramps in the tunnel are at very slight angles. The angles are just enough that the train just barely has enough clearance to go under the exiting track of the tunnel. Who knows, maybe the angles are still too extreme and in need of modifying to extend the ramp out further making for a slightly less uphill angle.

     A couple of things to note here in case it may help you guys. I don’t know if this info is important or not, so just to be safe, I’ll give you all the info I can:
   1 â€" We go through roughly one engine a week. Either from them burning out, or the “drive shaft” coming off of the little pin that connects it to the worm gear that runs the wheels.
   2 â€" The train slows almost to a crawl as it is trying to come out of the tunnel. The amperage drops to almost 0 once it enters the tunnel (probably from the momentum and weight of the other cars pushing it “downhill”), but climbs to 0.3 - 0.4 as it is trying to come out of the tunnel.
   3 â€" In running some tests, I found the following:
With only 5 cars, neither the voltage nor amperage changed nor was there any noticeable speed up of the train coming out of the tunnel.
With only the engine and coal car full of BB’s there was no change in the voltage and only a 0.1 drop in the amperage as it is coming out of the tunnel. Although there was a noticeable difference in speed of it coming out of the tunnel.

     Now for the questions;
   Would it help, or even make a difference, to use two engines to pull all the cars instead of one?

   Is there any limit to the number of cars that can be pulled by a single engine with out burning out the engine out over time or putting too much stress on it?

   Is there a better engine to use than the one we are using? (maybe one that has a better pulling capability or will just stand up to the constant use longer)

   By having the extra weight of the added BB’s in the coal carrier, is that actually helping or hurting?

   Would it help to add some weight to the engine itself? (There is enough clearance inside that housing that I could rig up some extra weight in it if you guys think it would help)

   Would it help to add a slight berm to the outside curves, and if so, what is the best way to do such a thing?

   Would it help to add another contact terminal? (Maybe right at the exit of the tunnel where the train likes to slow down)

   I have already told you what we use and how we clean the track and wheels, is there anything better to use or a better way to clean the tracks? How often would you suggest that we clean the tracks?

     On a final note: If any of you live near us, or plan on being near here, and would like to stop in to take a look at our set-up so you could (hopefully) give us some advice, please contact me (or just post here) and I am sure I can get you in for free. Just a way of saying “Thanks for the help”.

     I would like to thank you guys in advance for any help or advice you can give us on getting this aggravating &*$#@% running the way it should.
    I also wish to apologize for the length of this post, I was just trying to give as much info as possible.